dO.V/-QA' HUMAN PHYSIOLOGY. \ * HUMAN PHYSIOLOGY. BY ROBLEY DUNGLISON, M.D.,LL.D., • • • PROFESSOR OF THE INSTITDTES OF' MEDICINE IN JEFFERSON MEDICAL COLLEGE, PHILADELPHIA; VICE-PRESIDENT OF THE AMERICAN PHILOSOPHICAL SOCIETY, ETC. ETC. "Vastissimi studii priinas quasi lineas circumscripsi."—Ealler. FIVE HUNDRED AND THTRTY-TWO ILLUSTRATIONS. EIGHTH EDITION, REVISED, MODIFIED, AND ENLARGED. IN TWO YOLTJMES. VOL. II. K*4* PHILADELPHIA: BLANCHAUD AND LEA 1856. ST . :.'-■■ 9/ .< h IZ5G v, 3, Entered according to the Act of Congress, in the year 1841, by ROBLEY DUNGLISON, in the Clerk's Office of the District Court for the Eastern District of Pennsylvania. PHILADELPHIA: T. K. AXD P. G. COLLINS, PRINTERS. CONTENTS OE VOL. II. BOOK II. ANIMAL FUNCTIONS. Chap. I. Sensibility (continued) . D. Sense of Hearing or Audition 1. Anatomy of the Organ of Hearing 2. Sound .... 3. Physiology of Audition . E. Sense of Sight or Vision 1. Light .... 2. Anatomy of the Organ of Vision . 3. Accessory Organs . 4. Physiology of Vision 5. Phenomena of Vision F. Additional Senses . b. Internal Sensations G. Mental Faculties, &c. Physiology of the Intellectual and Moral Faculties Chap. II. Of Muscular Motion, especially Locomotility or Voluntary Motion 1. Anatomy of the Motory Apparatus . a. Muscles . b. Bones . 2. Physiology of Muscular Motion 3. Attitudes . 4. Movements . a. Locomotive Movements . a. Walking b. Leaping c. Running d. Swimming e. Flying . f. Other varieties of Muscular Action 5. Function of Expression or of Language a. Of the Voice 1. Anatomy of the Vocal Apparatus 2. Physiology of the Voice a. Intensity or Strength of Voice b. Tone of Voice VI CONTENTS. c. Timbre or Quality of Voice . d. Natural or Inarticulate Language e. Artificial or Articulate Language /. Singing b. Gestures . 6. Ciliary Motion PAGE 319 326 327 338 341 356 BOOK III. REPRODUCTIVE FUNCTIONS. Chap. I. Generation 1. Generative Apparatus a. Genital Organs of the Male 1. Sperm . b. Genital Organs of the Female 1. Menstruation c. Sexual Ambiguity 2. Physiology of Generation a. Copulation b. Fecundation c. Theories of Generation d. Conception e. Superfoetation f. Pregnancy g. Signs of Pregnancy h. Duration of Pregnancy i. Parturition j. Lactation . Chap. II. Fcetal Existence.—Embryology . 1. Anatomy and Histology of the Foetus a. Foetal Developement b. Foetal Dependencies c. Foetal Peculiarities 2. Physiology of the Foetus a. Functions of Nutrition b. Animal Functions c. Functions of Reproduction 360 370 370 3S0 387 4o2 416 422 423 427 454 474 485 487 498 505 509 515 527 527 527 547 563 572 573 598 600 BOOK IY Chap. I. Ages 1. Infancy a. First period of Infancy b. Second period of Infancy or first Dentition c. Third period of Infancy 2. Childhood . 3. Adolescence . 4. Virility or Manhood 5. Old Age 601 601 601 606 612 612 616 619 620 CONTENTS. Chap. II. Sleep ....... 1. Dreams ...... 2. Waking Dreams . 3. Revery ...... Chap. III. Correlation of Functions .... 1. Mechanical Correlations .... 2. Functional Correlations .... 3. Sympathy ...... a. Sympathy of Continuity .... b. Sympathy of Contiguity .... c. Remote Sympathies .... d. Imagination ..... e. Superstitions connected with Sympathy . f. Agents by which Sympathy is accomplished Chap. IV. Individual Differences amongst Mankind 1. Temperaments . a. Sanguine Temperament .... b. Bilious or Choleric Temperament c. Melancholic or Atrabilious Temperament d. Phlegmatic, Lymphatic or Pituitous Temperament e. Nervous Temperament .... 2. Idiosyncrasy ..... 3. Natural and Acquired Differences . a. Natural Differences .... 1. Peculiarities of the Female b. Acquired Differences .... 1. Habit ...... 2. Association ..... 3. Imitation ..... 4. Varieties of Mankind .... 1. Division of the Races .... a. Caucasian Race .... b. Ethiopian Race .... c. Mongolian Race .... d. American Race .... e. Malay Race ..... 2. Origin of the Different Races Chap. V. Life ....••• Chap. VI. Death ....••• 1. Death from Old Age .... 2. Accidental Death . . Index ....•••■ LIST OE ILLUSTRATIONS IN VOL. II. FIG. 246. General view of the external, middle, and internal ear, as seen in a pre pared section, from Scarpa, 247. Anterior view of the external ear, as well as of the meatus auditorius labyrinth, &c, . . 248. Membrana tympani from the outer (a) and from the inner (b) sides, 249. Ossicles of the left ear articulated, and seen from the outside and below, 250. Labyrinth separated from the solid bone in which it lies embedded, 251. Cochlea of a new-born infant, opened on the side towards the apex of the petrous bone, after Arnold, 252. Interior of the osseous labyrinth, after Sommering, 253. Membranous labyrinth of the left side with its nerves and otoliths, after Breschet, .... 254. Auditory nerve, 255. Auditory nerve taken out of the cochlea, 256. Papilla? of the auditory nerve, on a segment of the spiral lamina of the cochlea of a young mouse, 257. Reflection of sound, . 258. Vertical section of the head and neck, through the mesial line, to show the opening of the Eustachian tube and its relations to the pharynx, 259. Reflection and refraction of light, 260. Prism, 261. Double convex lens, 262. Double concave lens, 263. Prismatic spectrum, 264. Aberration of sphericity, 265. Aberration of refrangibility, . 266. Front view of the left eye—moderately opened, 267. Choroid coat of the eye, 268. Pigmentum nigrum, after Todd and Bowman, 269. a. An enlarged plan of the retina, in section, b. The outer surface of Jacob's membrane, from Hannover, 270. Part of the retina of a frog seen from the outer surface, 271. Vertical section of the human retina and hyaloid membrane, after Todd and Bowman, 272. Papillae of the retina of the frog, seen from the side turned towards the vitreous humour, ...... 273. Vertical section of retina of human eye, after H. Miiller, . 274. Plan of the structures in the fore part of the eye, seen in section, X LIST OF ILLUSTRATIONS. FIG. 275. Ophthalmoscope, ........ 276. Posterior segment of transverse section of the globe of the eye seen from within, ......... 277. Vertical section of the sclerotic and cornea, showing the continuity of their tissue between the dotted lines, after Todd and Bowman, . 278. Longitudinal section of the globe of the eye, .... 279. Lens, hardened in spirit and partially divided along the three interior planes, as well as into lamella?.—Magnified three and a quarter diame- ters, after Arnold, ...... 280. Front view of the crystalline humour or lens, in the adult, 281. Side view of the adult lens, ..... 282. Internal view of the iris, ..... 283. External view of the iris, ..... 284. Muscular structure of the iris of a white rabbit, after Kolliker, 285. Anterior segment of a transverse section of the globe of the eye seen from within, ........ 286. Choroid and iris, exposed by turning aside the sclerotica, after Zinn, 287. Diagram to show the position and action of the ciliary muscle, after Todd and Bowman, ...... 288. Optic nerves, with the origin of seven other pairs of nerves, 289. Course of fibres in the chiasma of the optic nerves, after Todd and Bowman 290. Muscles of the eyeball, 291. Meibomian glands seen from the inner or ocular surface of the eyelids with the lachrymal gland—the right side, 292. View of the third, fourth, and sixth pairs of nerves, 293. Posterior view of the eyelids and lachrymal gland, after Sommering, 294. Lachrymal canals, ..... 295. Scheme of the progress of luminous rays through the eye, 296. Camera obscura, 297. Experiment of Mariotte, 298. Muscae volitantes, after T. W. Jones, 299. Lines of visible direction, 300. Accidental colours, . 301, 302. Myopic vision, . 303, 304. Presbyopic vision, 305. Binocular vision.—Professor Wheatstone's experiments, 306, 307. Binocular vision, 308. Do. do. 309. Multiple vision with one eye, 310. Do. do. 311. Visual angle, 312. Foreshortening, 313. Perspective, . ... 314. Apparent magnitude, after Budge, . 315. Concave mirror, 316. Convex mirror, 317,318. Thaumatrope, . 319. Facial line and angle of man, after Sir C. Bell, 320. Vertical section of skull of Papuan Negrito, after Owen, 321. Facial line and angle of orang-outang, 322. Vertical section of skull of adult orang, after Owen, 323. Vertical section of skull of young orang, after Owen, page 63 64 65 65 LIST OF ILLUSTRATIONS. XI FIG. page 324. Old phrenological head, . . . . . . .186 325. Phrenological head by Dolci, A. D. 1562. . . . . . 1S6 326, 327, 328. Phrenological organs according to Gall, .... 190 329, 330, 331. Phrenological organs according to Spurzheim, . . .193 332, 333. Non-striated muscular fibre, after Bowman and Wilson, . . 210 334, 335. Striated muscular fibres, ..... 211-12 336. Fragments of an elementary fibre of the skate, held together by the un- torn but twisted sarcolemma, after Todd and Bowman, . . .212 337. Transverse section of fibres from the pectoral muscle of a teal, after Bow- man, ......... 213 338. Transverse section of ultimate fibres of biceps, after Bowman, . . 213 339. Fragment of muscular fibre from macerated heart of ox, showing formation of striae by aggregation of beaded fibrillae, after Bowman, . . 214 340. Portion of human muscular fibre, separating into disks, by cleavage in direction of transverse striae, after Bowman, .... 214 341. Fragments of striated elementary fibres, showing a cleavage in opposite directions.—Magnified 300 diameters, . . . . .214 342. Mass of ultimate fibres from the pectoralis major of the human foetus, at nine months, after Wilson, ...... 343. Muscular fibrils of the pig, after Sharpey, ..... 344. Attachment of tendon to muscular fibre, in skate, after Bowman, . 345. Capillary network of muscle, after Berres, ..... 346. Compound ventriform muscle, ...... 347. Penniform muscle, ........ 348. Double penniform muscle, ....... 349. Sections of a bone, ........ 350. Haversian canals, seen on a longitudinal section of the compact tissue of the shaft of one of the long bones, after Todd and Bowman, . . 227 351. Transverse section of compact tissue of humerus, magnified about 150 dia- meters, ......... 228 352. Direction of encephalic, impulses, . . . . . .239 353. Muscular fibre of dytiscus in contraction, after Bowman, . . . 244 354. Muscular fibre of skate, ....... 245 355. Centre of gravity, ........ 266 356. Do. do. ....... 266 357. Condition of equilibrium, ....... 267 358, 359. Composition of forces, ....... 267 360. Do. do. ...... . 268 361. Lever of the first kind, ....... 269 362. Lever of the second kind, ....... 269 363. Lever of the third kind, ....... 269 364-65. Action of the deltoid, ...... 271-72 366. Action of the biceps, ........ 272 367. Insertion of fibres into tendon, ...... 273 368. Tendon of the great toe, ....... 274 369, 370, 371, 372, and 373. Action of intercostal muscles, . . 275-76 374. Action of biceps, ........ 277 375. Combined muscular movements in,rising, ..... 277 376 Ligamentum nuchae, ........ 284 377. Lateral view of a dorsal vertebra, ...... 285 378. Lateral view of a lumbar vertebra, ...... 285 379. Upper portion of thigh-bone, ...... 286 XII LIST OF ILLUSTRATIONS. FIG. 3S0. Movement of the foot in walking, . 381. Lateral view of the larynx, ...... 382. View of the interior of the left half of the larynx, to show the ventricle and laryngeal pouch, after Hilton, ..... 383. Larynx from above, after Willis, ..... 384. Do. do. do. .... 385, 386. External and sectional views of the larynx, after Willis, 387. Scheme of the larynx, ....•■ 388. Origin and distribution of the eighth pair of nerves, 389. Scheme of a bird-call, ...... 390. Do. do. ...... 391. Muscles of the head and face, ..... 392. Distribution of the facial nerve, ..... 393. Plan of the branches of the fifth nerve, modified from a sketch by Sir C Bell, ........ 394. Paralysis of the facial nerve, after Marshall Hall, . 395. Broad laughter, after Sir Charles Bell, .... 396. Faun weeping, after Sir Charles Bell, . . . . 397. Physiognomy of melancholy, after Sir Charles Bell, 398. Cilia, ......... 399. Vibratile or ciliated epithelium, ..... 400. Male organs'; after Sir C. Bell, ..... 401. Human testis injected with mercury, after Lauth, . 402. Plan of the structure of the testis and epididymis, after Lauth, 403. Vertical section of the union of vas deferens and vesiculae seminales so as to show their cavities, ...... 404. Section of the penis, ....... 405. Glans penis injected, ...... 406. Portion of the erectile tissue of the corpus cavernosum magnified, to show the areolar structure and the distribtion of the arteries, after Miiller, 407. A single tuft or helicine artery projecting into a vein, highly magnified after Miiller, ....... 408. Spermatozoa from man, and their developement, after Wagner, 409. Developing vesicles of spermatozoids from the testicle of the dog, after Wag ner and Leuckardt, ...... 410. Spermatozoid of the dog in the interior of the vesicle of developement, after Wagner and Leuckardt, ...... 411. External organs of generation in the unmarried female—the vulva being partially opened, ....... 412. Side view of viscera of female pelvis, .... 413. Lateral view of the erectile structures of the external organs of generation in the female, the skin and mucous membrane being removed, after Kobelt, ......... 414. Front view of the erectile structures of the external organs of generation in the female, after Kobelt, . . • . 415. Anterior view of the uterus and appendages, after Quain and Sharpey, 416. Posterior view of the uterus and its appendages: the cavity of the uterus being shown by the removal of its posterior wall; and the vagina being laid open, after Quain and Sharpey, ..... 417. Vaginal mucus containing trichomonads, magnified 400 diameters, after Donne, ......... 418. Section of uterus, ........ 390 391 391 392 393 394 LIST OF ILLUSTRATIONS. Xlll FIG. 419. Section of the paries of the uterus, magnified three diameters, after Coste, 420. Nerves of the uterus, after R. Lee, . 421. Fallopian tube, ..... 422. Section of ovary ..... 423. New-laid egg with its molecule, &c, after Sir E. Home, 424. Constituent parts of mammalian ovum, after Coste, 425. Ovum of the sow, after Barry, 426. Diagram of a Graafian vesicle, containing an ovum, after Wagner, 427. Ovarium laid open, with Graafian vesicles in various stages of evolution after Coste, 428. Ovarium of the living hen, natural size. The ova at different stages of evolution, after Sir E. Home, .... 429. Ovary of a female dying during menstruation, 430. Hermaphrodism, after Blackman, .... 431. Tubal pregnancy, ...... 432. Corpora lutea of different periods, .... 433. Corpus luteum in the third month, after Montgomery, 434. Corpus luteum at the end of the ninth month, after Montgomery, 435. Successive stages of the formation of the corpus luteum in the Graafian follicle of the sow, after Pouchet, . 436, 437. Corpora lutea, after Sir E. Home, 438, 439. Corpora lutea, after Sir E. Home, 440. Decidua uteri, after Von Baer, 441. Section of the uterus about eight days after impregnation, after Wagner, 442. Section of the uterus when the ovum is entering its cavity, after Wagner, 443. Section of the uterus with the Ovum somewhat advanced, after Wagner, 444. Extra-uterine pregnancy, ....... 445. Two thin segments of human decidua, after recent impregnation, viewed on a dark ground; they show the openings on the surface of the mem- brane, after Sharpey, 446. Section of the lining membrane of a human uterus at the mencing pregnancy, after E. H. Weber, . 447. First stage of the formation of the decidua refiexa around Coste, ...... 448. More advanced stage of decidua refiexa, after Coste, 449. Natural labour, 450. Rotation of the head in its exit, 451. Breech presentation, 452. Arm presentation, 453. Twin case, 454. Milk ducts in human mamma, after Sir Astley Cooper, 455. The mammary gland after the removal of the skin, 456. Vertical section of the mammary gland, 457. Commencement of milk ducts as exhibited in a mercurial Sir Astley Cooper, .... 458. Ultimate follicles of mammary gland, after Lebert 459. Milk globules, after J. E. Bowman, . 460. Colostrum corpuscles, after J. E. Bowman . 461. Section of bird's egg, 462. Duplication of cells, .... 463. Cleaving of the yolk after fecundation, PAGE 395 396 397 397 398 399 400 400 400 401 408 420 430 446 446 447 448 448 449 487 488 488 489 492 493 i period of com 494 the ovum, aftei 495 495 510 511 513 513 515 516 517 517 . injection, aftei 517 517 525 525 529 530 530 XIV LIST OF ILLUSTRATIONS. FIG. 464. Progressive stages in the segmentation of the yolk of the mammalian ovum, after Coste, ........ 465. Later stage in the segmentation of the yolk of the mammalian ovum, after Coste, . . . • 466. Membrana granulosa of an ovum from the ovary, after Bischoff, . 467. Ova from the Fallopian tube and uterus, .... 468. Portion of the germinal membrane of a bitch's ovum, with the area pellu cida and rudiments of the embryo, magnified ten diameters, 469. Portion of the germinal membrane, with rudiments of the embryo from the ovum of a bitch, after Bischoff, ..... 470. Vascular area in the chick thirty-six hours after incubation, after Wagner 471. Egg thirty-six hours after incubation, after Sir E. Home, . 472. Egg opened three days after incubation, after Sir E. Home, 473. Embryo of the chick at the commencement of the third day, as seen from the abdominal aspect, after Wagner, . . 474. Embryo from a bitch at the 23d or 24th day, magnified ten diameters, after Bischoff, ........ 475. Plan of early uterine ovum, after Wagner, .... 476. The amnion in process of formation, by the arching over of the serous lamina, after Wagner, ...... 477. Diagram representing a human ovum in the second month, after Wagner 478. Egg five days after incubation, after Sir E. Home, . 47!). Egg ten days after incubation, after Sir E. Home, . 480. The umbilical vesicle, allantois, &c, .... 481. Ovum fourteen days old, ...... 4b 2. Ovum and embryo fifteen days old, after Maygrier, . . 483. Ovum and embryo twenty-one days old, after Maygrier, 484. Foetus at forty-five days, ...... 485. Foetus at two months, ...... 486. Corpora Wolffiana, with kidney and testes, from embryo of birds, . 487. Foetus at three months, in its membranes, .... 488. Full period of utero-gestation, ..... 489. Entire human ovum of eighth week, after Ecker, . 490. The extremity of a villus magnified 200 diameters, after Weber, . 491. Portion of the ultimate ramifications of the umbilical vessels, forming the foetal villi of the placenta, after J. Reid, .... 492. Diagram of the structure of the placenta, after J. Reid, 493. Portion of one of the foetal villi about to form part of the placenta, highly magnified, after Ecker, ...... 494. Connexion between the maternal and foetal vessels, after J. Reid, . 495. Section of a portion of a fully formed placenta, with the part of the uterus to which it is attached, after Ecker, .... 496. Extremity of a placental villus, after Goodsir, 497. Uterine surface of the placenta, . ... 498. Foetal surface pf the placenta, ..... 499. Knotted umbilical cord, ...... 500. Section of thymus gland at the eighth month, after Sir Astley Cooper, 501. Portion of thymus of calf, unfolded, after Kolliker, . 502. Section of human thymus, after Kolliker, .... 503. Transverse section through an injected lobule of the thymus, after Kolliker, 504. Circulatory organs #f the foetus, after Wilson, . . . . PAGE 531 LIST OF ILLUSTRATIONS. XV FIG. PAGE 505. Descent of the testicle, after Curling, . . . . .571 506, 507. Diagrams illustrating the descent of the testis, . . . 571 508, 509. Diagrams of the circulation in the human embryo and its appendages, after Coste, ........ 589 510. Schemes of sections of the lower jaw of the foetus at different periods, to show the stages of developement of the sac of a temporary incisor and of the succeeding permanent tooth from the mucous membrane of the jaw, after Goodsir, ........ 608 511. Front view of the temporary teeth, ...... 609 512. The separate temporary teeth of each jaw, ..... 609 513. Vertical section of an adult bicuspis, cut from without inwards; greatly magnified, after Retzius, ....... 610 514, 515. View of an incisor and of a molar tooth, given by a longitudinal sec- tion, showing that the enamel is striated and that the striae are all turned to the centre. The internal structure is also seen, . . . 611 516. A. Permanent rudiment given off from the temporary in an incisor, b. Permanent rudiment given off from the temporary in a molaris, . 612 517. Temporary tooth and permanent rudiment, after T. Bell, . . . 613 518. Temporary teeth and permanent rudiments, after T. Bell, . . . 613 519. Do. do. do. 614 520. Deciduous and permanent teeth, aet. 7, .... 614 521. Side view of upper and lower jaw, showing the teeth in their sockets. The outer plate of the alveolar processes has been taken off, . . 614 522. Upper and lower teeth, . . ' . . . . . 615 523. Skull of the aged, after Sir C. Bell, . . . . . .620 524. Physiognomy of the aged, after Sir C. Bell, ..... 621 525. Curves indicating the developement of the height and weight of male and female at different ages, after Quetelet, . . . . .623 526. Caucasian variety, after Blumenbach, ..... 678 527. Oval skull of a European, after Prichard, ..... 678 528. Negro skull, after Prichard, . . . . . . .680 529. Ethiopian variety, after Blumenbach, ..... 682 530. Mongolian variety, after Blumenbach, ..... 682 531. American variety, after Godman, ...... 683 532. Curves indicating the viability or existibility of male and female at different ages, after Quetelet, ....... 731 HUMAN PHYSIOLOGY. BOOK II. ANIMAL FUNCTIONS. CHAPTER I. SENSIBILITY. {CONTINUED.) D. SENSE OF HEARING OR AUDITION. Audition makes known to us the peculiar vibrations of sonorous bodies, that constitute sounds. It differs from the senses which have already been described, in the fact, that contact is not required between the organ of sense and the sonorous body; or between it and any ema- nation from that body. It is, however, a variety of touch, but produced by a medium acted upon by the vibratory body. 1. ANATOMY OF THE ORGAN OF HEARING. The auditory apparatus is a subject of intricate study to the young anatomist; and unfortunately when he has become acquainted with the numerous minute portions to which distinct and difficult appellations have been appropriated, he has, as in many other cases, attained a tedious detail of names, without having added to his stock of physio- logical information. Happily, it is not necessary for our purpose to go so minutely into the description of the organ of hearing. Accord- ing to the plan hitherto pursued, allusion will be made to those por- tions only that concern the physiological inquirer. In the ear, as well as in the eye, we have the distinction between the physical and nervous portions of the organ more clearly exhibited than in the skin, mouth, or nose. The nervous portion is situate deeply within the organ; and the parts between it and the exterior act physi- cally—on sonorous vibrations, in the case of the ear; and on light, in that of the eye. The organs of the senses hitherto considered are symmetrical. Those of audition are two in number, distinct but harmonious, and situate at the sides of the head, in a p^rt of the temporal bone, generally called, from its hardness, pars petrosa, and by the French and German anato- VOL. II.—2 18 SENSIBILITY. mists regarded as a distinct bone, under similar appellations—Le Rocher, and Felsenbein, (" rockbone.") This bone is seated at the base of the skull, so that the internal parts of the auditory organ are deeply and securely lodged. For facility of description, the ear may be divided into three por- tions : — 1. External ear or that exterior to the membrana tym- pani; 2. Middle ear— the space contained between the mem- brana tympani and internal ear; and 3. The internal ear in which the auditory nerve is distributed. 1. External ear. This portion of the auditory apparatus is commonly looked upon as an acoustic instrument, for col- lecting the sonorous rays or vibrations, and directing them, in a concentrated state, to the parts within. It is com- posed of the pavilion, and meatus auditorius externus. The pavilion varies in size and position in different individuals. It is the fibro-cartilaginous, thin, expanded portion, which is an append- age, as it were, to the head. It is irregular on its anterior surface; presenting several eminences and depressions. The eminences are five in number; and have been called, by anatomists, helix, anthelix, tragus, antitragus and lobe. The helix forms the rim of the pavilion: the tragus is the small nipple-like projection on the facial side of the meatus auditorius; the antitragus is the projection opposite to this__ forming the lower portion of the anthelix; and the lobule is the fatty, pendulous portion, to which ear-rings are attached. The depressions are three in number—the groove of the helix or cavitas innominata; the fossa navicularis or scapha ; and the concha. The name of the first sufficiently indicates its situation; the second is nearer the meatus auditorius; and the third is the expanded portion, which joins the commencement of the meatus, and is bounded by the anthelix, tragus and antitragus. The pavilion is supple and elastic; and, beneath°the skin are numerous sebaceous follicles, which are distinctly perceptible and give the skin its polish, and probably a portion of its suppleness! On the different eminences, some muscular fibres are perceptible, which" it is not necessary, for our purpose, to distinguish; for in man at least General View of the External, Middle, and Internal Ear, as seen in a Prepared Section. a. The auditory canal. 6. The tympanum or middle ear. c. Eusta- chian tube, leading to the pharynx, d. Cochlea ; and e. Semicircular canals and vestibule, seen on their exterior, as brought into view by dissecting away the surrounding petrous bone. The styloid process projects below ; and the inner surface of the carotid canal is seen above the Eustachian tube. ORGAN OF HEARING. 19 Anterior View of the External Ear, as well as of the Meatus Audito- rius, Labyrinth, or, again, it may tra- verse media of different \ \ -i, natures and densities, and be made to deviate from its original course, or be refracted. When a ray of light falls upon an opaque body, as upon a bright metallic or other mirror, it is reflected from the mirror, in such a man- ner, that the angle made by the incident ray with a perpendicular to the surface of the medium atthe point of incidence, is exactly equal to that made by the reflected ray with the same perpendicular. Suppose I J to represent a plate of polished metal, or glass, rendered opaque by a metal spread upon its posterior surface, as in the common looking-glass. The rays, proceeding from an observer at K, will be reflected back to ;, 1 Q \ M » N Reflection and Refraction of Light. 52 SENSIBILITY. him in the same line K C ; that is, in a line perpendicular to C, the point of incidence. The observer will, therefore, see his own image; but, for reasons to be mentioned hereafter under optical illusions, he will seem to be as far behind the mirror as he really is before it, or at E. Suppose, on the other hand, that the observer is at A, and that a luminous body is placed at B: in order that the rays, proceeding from it, shall impinge upon the eye at A, it is necessary that the latter be directed to that point of the mirror from which a line, drawn to the eye, and another to the object, will form equal angles with the perpendicu- lar; in other words, the angle B C K or angle of incidence must be equal to the angle of reflection, A C K. In this case, again, the object will not appear to be at B, but in the prolongation of the line A C, at H, as far from the point of incidence C as B is. Except in the case of illusions, the study of the reflection of light or catoptrics does not concern vision materially. It is on the princi- ples of dioptrics, that the chief modifications are effected on the pro- gress of the light through the physical part of the organ ; and, without a knowledge of these principles, the subject would be totally unintel- ligible. It is necessary, therefore, to dwell at some length on this topic. Whenever a ray of light passes through diaphanous or transparent bodies of different densities, it is bent or made to deviate from its course, and such deviation is called refraction; the ray is said to be refracted; and, owing to its being susceptible of such refraction, is held to be refrangible. The point, at which a ray enters the medium, is called the point of immersion; and that, by which it issues from such medium, the point of emergence. Instead of considering the medium IJ opaque, let it be regarded as transparent. C, in this case, will be the point of immersion for the incident rays that meet there ; and L and F will be the points of emergence for the rays K E and A C F G, respectively. If a ray of light, as K C, falls perpendicularly on the surface of any medium, it continues its course through it without ex- periencing any modification, and emerges in the same straight line. Hence a body at L will appear in its true direction and distance to an observer at K looking directly downwards on a pool of water, I J. If, on the other hand, a ray, as A C, after having passed through air, falls obliquely upon the surface of water B;—by entering a medium of different density, it is deflected from its course; and, instead of pro- ceeding in the direction C H, it is refracted, at the point of immersion, in the direction C F—that is, towards the perpendicular K E. If again, the ray emerges at F into a medium of the same density as that through which it passed in the course A C, it will proceed in a line parallel to A C, or in the direction F G, or will wander from the per- pendicular. The cause of this difference in the deflections produced by different media is not easy of explanation. The fact alone is known to us, that bodies refract light differently according to their densities and nature. If the light proceeds from a rarer to a denser medium it is attracted or refracted towards the perpendicular; if, on the contrary it passes from a denser to a rarer medium, it is refracted from the per- pendicular. The ray A C proceeded from a rarer medium—the air— into a denser, I J—water; it was refracted in the direction CF, towards the perpendicular K E. On emerging at F, circumstances were re- LIGHT. 53 versed; it wandered from the perpendicular MN, and in the direction F G, parallel to A C, because the media, above and below I J, were identical. We can now understand, why water, saline solutions, glass, rock-crystal, &c, have higher refractive powers than air. They are more dense. The nature or character of bodies greatly influences their refractive powers. Newton observed this in his experiments, and has furnished science with one of its proudest trophies, by his prognostic, in the then infant state of chemistry, that water and the diamond would be found to contain combustible ingredients. The diamond or brilliant is one of the most refractive of known substances, and this is one of the sources of its brilliancy. The opinion of Newton, it is hardly necessary to say, has been triumphantly confirmed. This refraction of rays, that fall obliquely upon a medium, gives rise to numerous optical illusions. The ray proceeding from F, in the bent course F C A, will impinge on an eye at A; and the object F will ap- pear to be at /. The pool will consequently seem shallower. In like manner, an object 0 in the air would not be perceptible to an eye in the water at F, in the direction 0 C F; whilst one at A would be dis- tinctly visible,—the ray from it proceeding in the direction A C F, but appearing to come straight to the eye in the direction 0 C F. All transparent bodies, at the same time that they refract light, re- flect a portion of it. This is the cause of the reflections we notice in the glass of windows, and of the image perceptible in the eye. The same substance has always the same refractive power, whatever may be its shape:—in all cases, the sine of the angle of refraction holding the same ratio to the sine of the angle of incidence, whatever may be the incidence. The angle of incidence is the angle formed by the incident ray with a perpendicular raised from the point of immersion; the angle of refraction that formed by the refracted portion of the ray with the same perpendicular. In Fig. 259, A C K is the angle of in- cidence of the ray A C; and L C F the angle of refraction. The sines of these angles respectively are the lines P Q and L F. But although media may refract the rays of light equally, the form of the refracting body materially modifies their arrangement. The perpen- diculars to the surface may approach or recede from each other ; and if this be the case the refracted rays will approach or recede from each other likewise. Where the body has plane and parallel surfaces, as the glass of our windows, the refraction, experienced by the ray on entering the glass, is corrected by that which occurs on its emergence; the light does not, therefore, proceed in one straight line, but in parallel lines separated by a space dependent upon the thickness of the refracting body, and the obliquity of the incident ray. If the medium be thin as in a pane of glass, the rays do not appear deflected from their original direction. In Fig. 259, the interval between the direct ray and the ray A C F after its emergence is that between G and H. If the surfaces of the dia- phanous body be plane, but inclined towards each other, as in the common prism, the refraction experienced by the ray, on emerging, instead of correcting that experienced during its passage through the body, is added to it; and the rays are deflected from their course to 54 SENSIBILITY. Prism. FiS- 26°- an extent equal to the sum of the two refrac- tions. The ray A B, Fig. 260, after imping- ing upon the side D L of the prism at B, instead of continuing its course in the direc- tion B J, is refracted towards the perpen- dicular C B F,—the medium being denser than air; and on emerg- ing into the rarer medium, Fig. 261. instead of continuing its course in the direction G I, it is refracted in the line G H, or from the perpen- dicular K J. Again, if the surfaces of the medium be convex, the rays are so situate, after refraction, as to converge behind the re- Douhie Conyex Lens. fracting body into a point called the focus, which is nearer to the medium the less the divergence of the rays, or in other words, the more distant the luminous object. Fig. 261 exhibits a pencil of rays, proceeding from a radiant point at A, and meeting at a focus at B; the dotted lines being the perpendiculars drawn to the surface at the points of immersion and emergence. Lastly; if the surfaces of the medium be concave, as in Fig. 262, the luminous rays, proceeding from a radiant point as at A, are rendered so divergent, that if we look for a focus here it must be anterior to the medium or at G. A knowledge of Fig. 262. D these facts has given occasion to the construction of numerous invalu- able optical instru- ments, adapted to modify the lumi- nous rays so as to change the situa- tion in which bodies are seen ; to aug- ment their dimen- sions; and to render them more lumi- nous and visible, when remote and . . , . . . . minute. It is to this branch of science that we are indebted for some of the most important information and advantages that we possess in the domains Double Concave Lens. LIGHT. k 55 of science and art. The simplest of these instruments are bodies shaped like a lentil, and hence called lenses. They are composed of two seg- ments of a sphere. The medium in Fig. 261 is a double convex; that in Fig. 262, a double concave lens. The manner in which they modify the course of the luminous rays passing through them has been suffi- ciently described. The study of the refraction of light leads to the knowledge of an extremely important fact; which, when it was first made known by Newton, excited universal astonishment;—that a ray of light is itself composed of several coloured rays differing from each other in their refrangibility. If a beam of the sun's light be admitted through the hole of a window-shutter, E F, Fig. 263, into a dark chamber, it will proceed in a direct line to P, and form a white spot upon the wall, or on a whitened screen placed there for the purpose. But if a glass prism, B A C, be placed, so that the light may fall upon its surface, C A, and emerge at the same angle from its second surface, B A, in the direction g G, the beam will expand; and if, after having emerged, it be received on the whitened screen, M N, it will be found to occupy a consider- able space; and, in- stead of the white spot, there will be an oblong image of the sun, K L, consisting of seven colours;— red, orange, yellow, green, blue, indigo, and violet. Each of these colours admits of no farther decom- position when again passed through the prism; and the whole lengthened image of the sun is called the prismatic or solar spectrum. In this dispersion of the coloured rays, it will be observed that the red ray is the least turned from its course; and is hence said to be the least refrangible; whilst the violet is most so. Such is the spectrum, as depicted by Newton: since his time, it has, by some, been reduced to three colours,—red, yellow, and blue; as cer- tain of the colours can be composed from others,—the green, for example, from the blue and yellow. Wollaston made it to consist of four; red, green, blue, and violet; Sir J. Herschel of four; red, yellow, blue, and violet: and, more recently. Sir David Brewster has restricted it to three; red, yellow, and blue. The causes which have led to these various divisions, it is not our province to explain. Each of the rays, of which the spectrum is composed, appears to have a different calorific and chemical action; but this also is a subject that nowise concerns the function under consideration. The decomposition of light into its constituent rays enables us to Fig. 263. PC- White Prismatic Spectrum. 56 SENSIBILITY. explain the cause of the colour of different substances. When white light impinges upon a body, the body either absorbs all the rays that compose it; reflects all; or absorbs some, and reflects others. If it reflects the whole of the light to the eye, it is of a white colour; if it absorbs all, or reflects none, it is black; if it reflects only the red ray, and absorbs all the rest, it is red; and so of the other colours. The cause, why one body reflects one ray, or set of rays, and absorbs others, is unknown. It is conceived to be owing to the nature and particular arrangement of its molecules; which is probable; but we are still as much in the dark as ever. It is accounting for the ignotum per igno- tius. Two other points require a brief notice, being intimately concerned in vision;—the aberration of sphericity, and aberration of refrangibility. It has been remarked, that rays of light—after passing through a con- vex lens, or medium whose surfaces are convex—converge, and are brought to a focus behind it. The whole of the rays do not, however, meet in this focus. Fig. 264. Those that are near- 1 est the axis, R" F -.'. of the lens, Fig. 264, |^ are refracted to a focus more remote from the lens, than those that fall on \lfir ...-•""' A the lens at a dis- yw...--"' tance from the .............\L/ axis. The rays R', Aberration of Sphericity. R » and R , are brought to a focus at F, whilst the rays R L, and W", L', converge at the point I, much nearer the lens. In like manner, rays which fall upon the lens inter- mediate between the rays R and B/, will have their foci intermediate between I and F. This diversity of focal distances is called spherical aberration or aberration of sphericity: the distance ZF is the longitudinal spherical aberration ; and B A the lateral spherical aberration, of the lens. This aberration is the source of confusion in common lenses; and as it is dependent upon the shape of the lens, it has been obviated by form- ing these instruments of such degrees of curvature, that the rays, falling upon the centre or margins of the lens, may be refracted to the same focus. This is effectually accomplished by lenses, whose sections are ellipses or hyperbolas. In a common glass, the inconvenience is ob- viated by employing a lens of a small number of degrees, or by inter- posing an opaque body—called, by the opticians, a diaphragm—ante- rior to the lens, so that the rays of light can only impinge upon the central part, and consequently be refracted to the same focus. This diaphragm is present in all telescopes, and occupies the situation of the curves D and D', so as only to admit the rays R', R", and R'", to fall upon the lens. Such an apparatus, we shall find, exists in the human eye. Lastly,—it has been already observed, that the different rays, consti- tuting the solar spectrum, are unequally refrangible,—the red being the R R- R"- R'"- BT.. 55�7975205 LIGHT. 57 ABC least, the violet the most so; hence the cause of their dispersion in the spectrum. It follows from this fact, that, whenever light experiences refraction, there must be more or less dispersion of its constituent rays; and the object, seen by the refracted ray, will appear coloured. This must, of course, occur more particularly near the margins of the lens, where the surfaces become less and less parallel until they meet. The inconvenience resulting from this dispersion is called the aberration of refrangibility or chromatic aberration, and it has been attempted to be obviated by glasses, which have been termed, in consequence, achro- matic. These are made by combining transparent bodies of different dispersive powers, in such sort, that they may compensate each other; and thus the object be seen in its proper colours, notwithstanding the refraction. Dr. Blair found, for example, that by enclosing chloride of antimony, B E, between two convex lenses of crown glass, A D and C F, the parallel rays R R and R were refracted to Fig. 265. a single focus at P with- out the slightest trace of secondary colour. New- ton was of opinion, that the light, in traversing a refracting medium, al- ways experiences a dis- persion of its rays, pro- portional toits refraction. He therefore believed, that it would be impos- sible to fabricate an achromatic glass. This is one of the rare cases in which that illustrious philosopher erred. Since his time—and chiefly by the labours of Mr. Dollond—instru- ments have been formed on the principles above mentioned, so as to greatly diminish the inconveniences sustained from the use of common lenses; although they may still not be perfectly achromatic. The in- convenience is farther obviated by the diaphragm in telescopes, already referred to. As the dispersion is most experienced near the margin of the lens, it shuts off the rays, which would otherwise fall upon that portion, and diminishes the extent of aberration. The human eye is achromatic. It is obviously essential that it should be so; and this result is owing to a combination of causes. It is formed of media of different dispersive powers. Its lens is constituted of layers of different densities, and it is provided with a diaphragm of singularly valuable construction.1 Such are the prominent points of the beautiful science of optics, that chiefly concern the physiologist as an introduction to vision. Others will have to be adverted to, as we consider the eye in action. 1 See Listing, art. Dioptrik des Auges, in Wagner's Handworterbuch der Physiologie iv. 451, Braunschweig, 1853; and Ludwig, Lehrbuch der Physiologie des Menscben, i. 192, Heidelb., 1853. s:;p DEF Aberration of Refrangibility. 58 SENSIBILITY. 2. ANATOMY OF THE ORGAN OF VISION. The human eye is almost spherical, except for the prominence at its anterior and transparent part—the cornea. It has been compared to a telescope, and with much propriety; as many of the parts of that in- strument have been added to execute Fig. 266. special offices, which are admirably performed by the eye—the most perfect of all optical instruments. Every telescope consists, in part, of a tube, which always comprises pieces, capable of readily entering into each other. Within this cylinder are glasses or lenses, placed in succes- sion from one extremity to the other. These are intended to refract the rays of light, and to bring them to deter- Front View of the Left Eye—moderately minate foci. Within the teleSCOpe is opene ' a kind of partition of paper or metal, 1. Supercilia. 2. Cilia of each eyelid. 3. In- . . x i i i • •: j feriorpalpebra. 4. Internal canthus. 5. External having a rOUnd hole in its Centre, and ^naris6' ?5Rffi}. ^^ '' "^ USUallJ PlaCed ™™ * COnVeX &**>> for the purpose of diminishing the surface of the lens accessible to the rays of light, and thus of obviating spherical aberration. The interior of the tube and of the diaphragm is coloured black, to absorb the oblique rays, which are not inservient to vision; and thus to prevent them from causing confusion. This arrangement is nearly a counterpart of that which exists in the eye. The tube of the instrument is represented by three membranes in superposition,—the sclerotic, choroid, and retina; the last receiving the impression of light. Within, are four refracting bodies, situate one behind the other; and intended to bring the rays of light to determinate foci,—the cornea, aqueous humour, crystalline lens, and vitreous humour. Lastly, in the interior of the eye, near the anterior surface of the crys- talline, is a diaphragm—the iris, having an aperture in its centre—the pupil. These different parts demand a more detailed notice. 1. Coats of the Eye.—Before describing the coats of the eye it may be remarked, that the eyeball is invested with a membranous tunic, which separates it from the other structures of the orbit; and forms a smooth, hollow surface by which its motions are facilitated. This in- vestment has been variously called, cellular capsule of the eye, ocular capsule, tunica vaginalis oculi, and submuscular fascia. The sclerotic is the outermost proper coat. It is that which gives shape to the organ, and which constitutes the white of the eye. It is of a dense, resisting, fibrous nature, belonging to what M. Chaussier calls albugineous tissue. Behind, it is penetrated by the optic nerve • and before, the cornea is dovetailed into it. It has, by some anatomists, been considered a prolongation of the dura mater, accompanying the optic nerve; whilst the choroid has been regarded as an extension of the pia mater; and the retina of the pulp of the nerve. The sclerotic is the place of insertion for the various muscles that move the eyeball ORGAN OF VISION. 59 Fig. 267. Choroid Coat of the Eye. 1. Curved lines marking the arrangement of Tense vorticosse. 2, 2. Ciliary nerves. 3. A long ciliary artery and nerve. 4. Ciliary ligament. 5. Iris. 6. Pupil. and is manifestly intended for the protection of the internal parts of the organ. Immediately within the sclerotica, and feebly united with it by ves- sels, nerves, and areolar tissue,1 is the choroid coat;—a soft, thin, vas- cular, and nervous membrane. It completely lines the sclero- tic ; and has, consequently, the same shape and extent. Be- hind, it is perforated by the optic nerve; before, it has the iris united with it; and within, it is lined by the retina, which does not, however, adhere to it,—the black pigment sepa- rating them from each other. It is chiefly composed of the ciliary vessels and nerves, and consists of two distinct laminae, to the innermost of which Ruysch—the son—gave the name membrana Ruyschiana. In fishes these lamina? are very perceptible, being separated from each other by a substance, which M. Cuvier considers to be glandular. The choroid is impregnated and lined by a dark-coloured mucous pigment, stratum pigmenti, pigmentum nigrum. In some cases, as in the albino, this substance, which is exhaled from the choroid, is light-coloured, approximating to white. Leopold Gfmelin2 conceives that it approaches the nature of indigo; Dr. Young,3 regards it as a mucous substance, united to a quantity of carbonaceous matter, upon which its colour de- pends; and Berzelius,4 from his chemical investigations, considers it to consist chiefly of carbon and iron; but Professor Jacob thinks it obvi- ously an animal principle sui generis, its elements being oxygen, hydro- gen, carbon, and nitrogen. Dr. Apjohn found 100 parts, in a dry state, leave, when incinerated, 446 of a calx consisting of chloride of calcium, carbonate of lime, phosphate of lime, and peroxide of iron. Mr. Thomas Wharton Jones has examined the layer of black pigment 1 In the situation of this areolar tissue, Arnold describes a serous membrane, Spinn- webenhaut, Arachnoidea oculi, Lamina fusca scleroticce.—Arnold liber das Auge, Tab. iii., Fig. 2, and Weber's Hildebrandt's Handbucb der Anatomie, iv. 68, Braunschweig, 1832. 2 Dissert. Sistens Indagationem Chemicam Pigmenti Nigri Oculorum Taurorum, Gotting., 1812. 3 Medical Literature, p. 521, Lond., 1813. 4 Medico-Chirurg. Trans., iii. 225. Fig. 268. Pigmentum Nigrum. A. Choroid epithelium, with the cells filled with pigment, except at a, where the nuclei are visible. The irregularity of the pigment-cells is seen. b. Grains of pigment. B. Pigment-cells from the substance of the choroid. A detached nucleus is seen.—Magni- fied 320 diameters. 60 SENSIBILITY. on the inner surface of the choroid microscopically. He states that it possesses organization, and constitutes a real membrane—pigmental membrane—consisting of very minute flat bodies of an hexagonal form, joined together at their edges.1 It is generally considered to consist of pigment cells, which form a kind of pavement, and are somewhat of a polyhedral shape; lying in a very regular manner, with some inter- cellular substance between them. On the outer side of the bottom of the cavity of the eye, there is a small shining space, desti Fig. 269. 3—. sil h tute of pigment, through which the colours of the membrana Ruyschiana ap- pear. This is termed tape- turn. It is met with only in quadrupeds. The retina is the last coat, if we except a highly deli- cate serous membrane—dis- covered by Dr. Jacob,2 of Dublin, and called after him Tunica Jacobi,—which is in- terposed between the retina and the choroid coat.3 It appears to be composed of cylindrical, transparent, and highly refractive bodies, which are arranged perpen- dicularly to the surface of the retina,—their outer ex- tremities imbedded, to a greater or less depth, in a layer of the pigmentum ni- grum. They form the ba- cillar layer of the retina of other observers. The only plausible suggestion, which, according to Messrs. Kirkes and Paget,4 has been offered, concerning the use of these bodies, is that of Briicke, who thinks it not unlikely, that they may serve to conduct back to the sensitive portion of the retina those rays of light which have traversed that membrane, and have not been entirely ab- sorbed by the pigmentum nigrum. Mr. George H. Fielding, of Hull,5 has affirmed, that immediately behind the retina, and in connexion with it, there is a peculiar membrane, separable into distinct layers 1 Art. Eye, by Dr. Jacob, in Cyclop, of Anat. and Physiol., Part x. p. 181, for June, 1837. 2 Philosoph. Transact, for 1819; Medico-Chirurg. Transactions, xii. Lond 1823 and Art. Eye, in Cyclop, of Anat. and Phys., p. 186. ' "' ' 3 Philosophical Transactions for 1829, p. 300. 4 Manual of Physiology, 2d American edition, p. 415, Philadelpbia 1853. 5 Second Report of the British Association for the Advancement of Science: or Amer Journal of the Med. Sciences, Nov., 1833, p. 220. A. An Enlarged Plan of the Retina, in section. 1. The nervous structure, viz., the nerve-fibres (b) between nerve-cells (a, c). 2. Jacob's membrane. 3. Inner surface of choroid, d. One of the small pointed bodies of Jacob's membrane. B. The Outer Surface of Jacob/a Membrane. Opposite e, the twin cones are obscurely seen, not being in focus, while, at the lower part of the figure, near/, the same bodies are clearly discernible. Towards the right side of the figure, where the objects are disturbed, the twin cones project like papillae, at g, the small rods being in a great measure lost at this place. And these (small bodies) are seen to become horizontal towards the extre- mity of the object, h, where some are in disorder. ORGAN OF VISION. 61 Fig. 270. from the choroid, and supplied with bloodvessels, which he proposes to name membrana versicolor. He presumes, that it receives the vibra- tions of light, and communicates them to the retina: the eyes, used for experiment, were those of the ox and sheep. The retina lines the choroid, and is a soft, thin, pulpy, and grayish membrane, formed chiefly, if not wholly, by the final expansion of the optic nerve. M. Ribes,1 indeed, esteems it a distinct membrane, on which the optic nerve is distributed;—a structure more consistent with analogy. On its inner surface it is in contact with the membrane of the vitreous humour; but they are not adherent. Anteriorly, it ter- minates near the anterior extremity of the choroid, forming a kind of ring, from which an extremely delicate lamina is given off. This is reflected upon the ciliary processes; dips into the intervals separating them, and, according to some anatomists, passes forward as far as the crystalline. Modern observers—Messrs. B. C. R. Langenbeck, Treviranus, Gottsche, Volkmann, E. H. Weber, Mi- chaelis, and others, have examined minutely into the anatomy of the retina, and have shown that it consists of several layers:—Langenbeck Fig. 271. iffti pi if \^- l. Part of the Outer Surface of the Retina of the Frog, showing the imbricated arrangement of the bacillar layer or Jacob's mem- brane.—Magnified 300 times. s« ft f.....mmmi^^MisM^ Vertical Section of the Human Retina and Hyaloid Membrane. h Hvaloid membrane, h'. Nuclei on its inner surface, c. Layer of transparent cells, connecting the hyaloid and retina. C. Separate cell enlarged by imbibition of water, n. Gray nervous layer, with its capillaries 1. Its fibrous lamina. 2. Its vesicular lamina. 1'. Shred of fibrous lamina detached 2'. Vesicle and nucleus detached, g. Granular layer. 3. Light lamina frequently seen, gr Detached nu- cleated particle of the granular layer, m. Jacob's membrane, m'. Appearance of its particles, when detached, m". Its outer surface.—Magnified 320 diameters. says three; Michaelis, four. The inner or fibrous lamina or layer of the true retina is considered to be formed by the optic nerve, which, at its entrance into the eye, divides into numerous small fasciculi of 1 Memoir, de la Societe Medicale d'Emulation, yii. 86. 62 SENSIBILITY. ultimate fibrils, that spread themselves out, so as to form a net-like plexus. From this plexus, the fibres of which lie in the plane of the surface of the vitreous humour, a very large Fig. 272. number of fibrils arises in a direction perpendi- cular to the surface, so as to be all directed towards the centre of the eye. These pass through a delicate layer of areolar tissue, con- taining a minute plexus of bloodvessels, and from this every fibril receives a sheath, which envelopes its extremity, and thus forms a Papillae of the Retina of the minute papilla. The surface of the retina, in fuSrw^rth^vUrt6. contact with the vitreous humour, is wholly ous humour. composed of these papillae, which are closely The four higher rows are set together; and have been regarded as iden- seen^sideways.-Magnined 300 ^j with ^ globules Qf the retiQa Qf Weber.1 The diameter of these globules in man, accord- ing to Weber, is from the ^'ooth to sioo^h 01>an inch. The arrangement of the constituent laminae or layers of the retina, as given by Todd and Bowman,2 is represented in Fig. 271; whilst Fig. 273 depicts them as pointed out by H. Miiller and Kolliker.3 There is much yet to learn, however, in regard to the exact constitution of the retina, and the histology and functions of its special parts in the exercise of vision, on which opinions are at this time very unsettled.4 About a sixth of an inch on the outside of the optic nerve, and in the direction of the axis of the eye, or of a line drawn perpendicularly through the centre of the cornea, is a yellow spot, about a line in extent, having a depression in its centre. This spot and depression are the limbus luteus or macula lutea, and fovea centralis, fovea optica or foramen centrah of Sommering.5 The yellow spot does not exist in the foetus ;6 and the folds, described by Sommering as surrounding the yellow spot, would appear to be a post mortem appearance. In the examination of two convicts, three hours after execution, the foramen was not seen satisfactorily.7 The retina receives many blood-vessels, which proceed from the 1 Carpenter, Human Physiology, p. 262, Lond., 1842. 2 The Physiological Anatomy and Physiology of Man, Amer. edit., p. 414 Philad.. 1850. ' * ' 3 Mikroskopische Anatomie, 2ter Band, S. 648, Leipz., 1854; or Amer. edit, of Syden- ham Society's edition of Kolliker's Manual of Human Histoloev bv Dr Da Co^ta n 739, Philad., 1854. &Jl * ' " ' v' 4 See, on this subject, Todd and Bowman, and Kolliker, in op. cit.; Giinther Lehr- buch der Physiologie des Menschen, von Dr. Otto Funke, 2ter Bd., 2ter Abth., S. 479, Leipz., 1853; and for the opinions of Gegenbaur, Leydig and Virckow, see Dr'. Robert T. Lyons, Annals of Micrology, in Brit, and For. Med.-Chir. Rev., April 1855 p. 561- for those of Remak, Canstatt's Jahresbericht, im Jahre, 1854, ler Bd.' S 56 or Dr' John W. Ogle's Report on Micrology, in Brit, and For. Med.-Chir. Rev!' Oct 1855 p' 524 ; and for those of Prof. Goodsir, Edinb. Med. and Surg. Journ. 'Oct. 'l855 ' or Amer. Journ. of the Med. Sciences, Jan., 1856, p. 189. 5 Sommering, in Comment. Societ. (Jotting., torn. xiii. 1795-98; A. ab Ammon de Genesi et Usu Maculae Luteae, &c, Vinar., 1830. ' e Rudolphi, Grundriss der Physiologie, B. ii. Abtheil, 1, S. 176, Berlin 1823 7 W. E. Horner, Special and General Anatomy, 5th edit., p. 426, Philad 1839 J. Pancoast in Wistar's Anatomy, 8th edit., Philad., 1842, and Bergmann in Henle's und Pfeuffer's Zeitschrift, v. 245 ; cited by Lyons in op. cit. ORGAN OF VISION. 63 Fig. 273. Fig. 274. * 111 Vertical Section of Retina of the Human Eye. 1. Bacillar layer. 2. Outer layer granular. 3. Intermediate, fibrous layer. 4. Inner granular layer. 5. Finely granular gray layer. 6. Layer of nerve-cells. 7. Layer of fibres of optic nerve. 8. Limitary membrane. Plan of the Structures in the Fore Part of the Eye, seen in section. 1. Conjunctiva. 2. Sclerotica. 3. Cornea. 4. Choroid. 5. Annulus albidus ; before this is seen the canal of Fontana. 6. Ciliary processes. 7. Iris. 8. Retina. 9. Hyaloid membrane. 10. Canal of Petit (made too large). 11. Membrane of the aque- ous humour (too thick), a. Aqueous humour: an- terior chamber and (a) posterior chamber, b. Crys- talline lens. c. Vitreous humour. central artery of the retina or of Zinn. This vessel—it is important to observe—enters the eye through the centre of the optic nerve, the porus opticus, and, before passing directly through the vitreous humour, sends off lateral branches to the retina.1 By means of a recently invented instrument, the ophthalmoscope, Fig. 275, the interior of the eyeball may be well seen. The luminous rays from an object at A are made to fall on a perforated reflector B C, and come to a focus so as to illuminate the retina. Some of these rays are reflected back, so as to enable an eye at E to observe the illumination. The bottom of a healthy eye is, in this manner, observed to be of a yellowish- red colour,—the colour being brighter in the immediate vici- nity of the optic centre than in other parts of the retina. The tint will vary in different eyes ac- Ophthaimoscope. cording to the hue of the pig- mentum nigrum. Close to the inner side of the entrance of the optic nerve the colour is darker at one point; which has been ascribed by 1 See, on the vessels of the globe of the eye, Dr. C. Sappey, Mem. de la Societe de Biologie, Annee, 1854, p. 243, Paris, 1855. 64 SENSIBILITY. Fig. 276. Helmholtz to the shadow of the semilunar fold of the retina. When the patient looks directly at the eye of the observer, and thus brings the axis of the eyes in the same line, the yellow spot of Sommering is perceived. The retina is there of a grayish yellow colour entirely free from any admixture of red; and no blood-vessels are seen on its surface.1 2. Diaphanous parts of the Eye.—The parts that act as refracting bodies are either transparent membranes, or fluids contained in cap- sules, which give them a fixed shape. These parts are the cornea, aqueous humour, crystalline, and vitreous humour. The cornea is the convex transparent part of the eye, advancing in front of the rest of the organ, as a watch-glass does before the case; and appearing like the segment of a smaller sphere superadded to a larger. It was, for a long time, considered to be a prolongation of the sclerotic; but they are manifestly distinct membranes, being separable by maceration. The posterior surface is concave, and, between it and the iris, is the small space occupied by the aqueous humour, called anterior chamber of the eye. The cornea is generally considered to be composed of several thin laminae in superposition, which have been com- pared to horn; and hence the name of the membrane; but Mr. T. Wharton Jones2 denies this, and describes it as consisting merely of interweaving bun- dles of fibres. Like corneous tissue in general, it possesses neither blood-vessels nor nerves. In animals the density and convexity of the cornea vary with the media in which they live, and with the condition of the other refractive parts of the eye. In old age, the membrane is harder, tougher, and less transparent than in youth; and it frequently be- comes completely opaque in its circum- ference, presenting the appearance called arcus senilis,—in German, Greisenbo- gen. Nerves have been traced into the substance of the cornea. They are rami- fications of the ciliary.3 The aqueous humour is a slightly viscid fluid, which occupies the whole of the space between the posterior surface of the cornea and the anterior surface of the crystalline. This space is divided by the iris into two chambers—an anterior and a posterior—the latter being the small in- 1 T. Wharton Jones, Report on the Ophthalmoscope in Brit, and For Med Chir Rev., Oct., 1854, p. 549; Dr. Hays, in his edition of A Treatise on Diseases of the Eve" by W. Lawrence, F. R. S., Amer. edit., p. 567, Philad., 1854; and Dr. Addinell Hew- son, in A Practical Treatise on the Diseases of the Eye, by William Mackenzie M D Amer. edit., p. xl., Philad., 1855. ' ' "' 2 Introduction to W. Mackenzie's Practical Treatise on Diseases of the Eye Lond 1840. In the 4th English edition, Mr. Jones remarks, that it " can scarcely'be said to be formed of distinct membranes." Amer. edit., by Dr. Addinell Hewsrm ™ „„,, Philad., 1855. ' p' XXVl * Lond. Med. Gaz., Oct., 1845, cited from Miiller's Archiv. Posterior Segment of Transverse Sec- tion of the Globe of the Eye seen from within. 1. Divided edge of three tunics. The membrane covering the whole internal surface is the retina. 2. Entrance of optic nerve with arteria centralis retinae piercing its centre. 3, 3. Ramifications of arteria centralis. 4. Foramen of Sommering, in centre of axis of eye ; the shade from sides of the section obscures the limbus luteus which surrounds it. 5. A fold of the re- tina, which generally obscures the fora- men of SJmmering after the eye has been opened. ORGAN OF VISION. 65 terval between the hinder surface of the iris, and the anterior surface of the crystalline. Sir David Brewster1 erroneously asserts that the Fig. 277. Vertical Section of the Sclerotic and Cornea, showing the continuity of their tissue between the dotted lines.. a. Cornea, b. Sclerotic. In the cornea, the tubular spaces are seen cut through, and in the sclerotic, the irregular areola. Cell-nuclei, as at c, are seen scattered throughout, rendered more plain by acetic acid.—Magnified 320 diameters. posterior chamber contains the crystalline and vitreous humours; and Dr. Arnott,2 that the an- terior and posterior cham- Fig- 278. bers of the eye are the compartments before and behind the crystalline. Anatomists are not agreed, whether the aqueous hu- mour have a proper mem- brane, which secretes it; or whether it be not an exhalation from the ves- sels of the iris and ciliary processes. M. Ribes de- rives it from the vitreous humour. Howsoever se- creted, it is very rapidly regenerated when evacu- ated; as it must be in every operation for cata- ract by extraction. It is not lodged in cells; and hence readily flows out when the cornea is punc tured aqueous humour, in the adult, is about five or six grains. Its specific gravity is not rigorously determined, but it differs slightly from that of water, being a little greater. According to Berze- 1 A Treatise on Optics, edit, cit., p. 241. 2 Elements of Physics, &c, 2d Amer. edit., vol. ii. P. i. p. 162, Philad., 1836. VOL. II.—5 Longitudinal Section of the Globe of the Eye. 1. Sclerotic, thicker behind than in front. 2. Cornea, received within anterior margin of sclerotic, and connected with it by means of a bevelled edge. 3. Choroid, connected anteriorly with (4) ciliary ligament, and (5) ciliary processes. 6. Iris. 7. Pupil. 8. Third layer of eye, retina terminating anteriorly by abrupt border at commencement of ciliary processes. 9. Canal of Petit, erjcircles the lens (12) ; the thin layer in front of this canal is the zonula ciliaris, a prolongation of vascular layer of retina to the lens. 10. Anterior chamber of eye containing aqueous humour ; the lining membrane, by which the humour is secreted, is repre- sented in diagram. 11. Posterior chamber. 12. Lens, more con- vex behind than before, enclosed in its proper capsule. 13. Vi- treous humour enclosed in hyaloid membrane, and in cells formed .«■ . in its interior by that membrane. 14. Tubular sheath of hyaloid The q Uantity Of membrane, which serves for the passage of the artery of capsule of the lens. 15. Neurilemma of optic nerve. 16. Arteria centralis retinaj, embedded in the centre. 6Q SENSIBILITY. Fig. 279. lius, it is composed of water, 98-10; a little albumen ; chlorides and lactates, 1*15; soda, with a substance soluble in water, 0'75. The crystalline lens is a small body, of a crystalline appearance, and lenticular shape,—whence its name. Its diameter, in the adult, is from four lines to four lines and a half; its axis or thickness about two lines or two and a half lines. It is situate between the aqueous and vitreous humours; and at about one-third of the antero-posterior diameter of the organ. A depression at the anterior surface of the vitreous humour receives it; and a reflection of the proper membrane of the humour passes over it. The crystalline is surrounded by its capsule, the interior of which is bathed by a slightly viscid and trans- parent secretion, called liquor Morgagnii. Kol- liker and others deny the presence of a true liquor Morgagnii during life; but its existence is defended by Lohmeyer.1 The lens is more convex behind than before; the radius of its anterior surface being, accord- ing to Sir David Brewster,2 0-30; and that of its posterior surface 0#22 of an inch. It con- sists of a number of concentric ellipsoid lamina?, increasing in density from the circumference to the centre. Some fibres detach themselves Lens, hardened in spirit and from the different lamina?; pass to those imme- thVeTiiiteriorpUneB^afweH diately beneath, and constitute the sole bond of Magnified union that exists between them. Of old it was believed that the crystalline was of a muscular structure, and capable of modifying its own convexity, so as to adapt the eye to different distances. This was the opinion of Des Cartes; and it has more recently been received, with modifications, by Dr. Young.3 Its muscularity ont View of the Crystalline is, however, by no means established, although Ad" °r LeDS' " the its fibrous character is unquestionable. The specific gravity of the human crystalline is said by Chenevix4 to be 1-0790. He consi- dered it to be composed chiefly of albumen. According to an analysis, however, of Berze- lius,5 it would appear to contain 35*9 parts in the hundred of a matter analogous to the co- louring matter of the blood. The vitreous humour, so called in consequence of its resemblance to glass, occupies the whole of the cavity of the eye behind the crystalline. It is convex behind; concave before; and is invested by a delicate, thin, transparent membrane, called tunica hna- loidea, which furnishes prolongations internally, that divide it into 1 Zeitschrift fur ration. Med. Bd. v. Heft i. p. 56; cited by Dr. Dav in Brit and For. Med.-Chir. Rev., Oct., 1855, p. 520. ' 7' n Unt' and 2 Op. citat., p. 242. See, also, Philos. Transact, for 1835, p. 366 s Philos. Transact, for 1793, p. 169 ; and Med. Literature, p. 521 Lond 1813 < Philos. Transact, for lb(.»3 p 195. 6 Medico-Chirurgical Transact iii 253 : intolamellae.- 3i diameters.. Fig. 280. Front Fig. 281. Side View of the Adult Lens. 1. Its anterior face. 2. Its pos- terior face. 3, 3. Its circumfe- rence. ORGAN OF VISION. 67 Fig. 282. cells. It is owing to this arrangement of the membrane, and not to the density of the humour, that it has the tenacity of the white of egg. Its density does not differ materially from that of the aqueous hu- mour;—their specific gravities being stated at T0009, and 1*0003 respectively. The cells, formed by the hyaloid membrane, are not all of the same shape and size. They communicate freely with each other, and are well represented in Fig. 278. At the anterior part, where the hyaloid membrane reaches the margin of the crystalline, it is separable into two lamina?; one of which is reflected over the ante- rior ; the other over the posterior surface of the lens. Between these lamina?, and at their junction round the crystalline, a canal exists, into which air may be introduced; when it exhibits a plaited arrangement, and has been called bullular canal of Petit;1 and, by the French wri- ters, canal godronne, or simply canal of Petit. This canal is generally conceived to be de- void of aperture; but Jacobson affirms, that it has, in its sides, a number of minute fora- mina, which admit the entrance and exit of the aqueous humour. The composition of the vitreous humour, according to Berzelius,8 is as follows:— Water, 9840; albumen, 0-16; chlorides and lactates, 1-42; soda, with an animal matter, soluble only in water, 0*02. Its absolute weight is fifteen or twenty times greater than that of the aqueous humour. 3. It was remarked, in the comparison drawn between the eye and a telescope, that a diaphragm exists in the former, called iris, and sometimes uvea. Generally, however, the latter term is appropriated to the posterior lamina of the iris. By some anatomists, the iris is conceived to be a prolongation of the choroid; by others, to consist of a proper membrane, of a muscular character; and, by others, again, to be essentially vas- cular and nervous; the vessels and nerves being distributed on an erectile tissue.3 There is, in the views of anatomists and physiologists, much discrepancy regarding the structure and functions of this portion of the eye. M. Edwards,4 of Paris, affirms, that it consists of four lamina?, two of which are extensions of laminae composing the choroid ; a third belongs to the membrane of the aqueous humour, and is reflected over its anterior surface; the fourth is the proper tissue of the iris. M. Magendie5 asserts, that the Internal View of the Iris. Fig. 283. External View of the Iris. 1 Mumoires de l'Academie des Sciences, Paris, 1723 and 1728 ; and Haller, Element. Physiol., xvi. 2, IS. •* Mcdico-Chirurgical Transactions, iii. 253. 3 Lepelletier, riiysiolo.de Medicale et Philosophique, torn. iii. p. 158, Paris, 1832. « Bullet, de la Societe Philom., etc., 1814, p. SI. 5 Op. citat., i. 61. 68 SENSIBILITY. Muscular Structure of the Iris of a White Rabhit. a Sphincter of the pupil. 6, 6. Radiating fasciculi of dilator muscle, c, c. Connective tissue with its cor- puscles. most recent anatomical investigations prove the iris to be muscular, and composed of two sets ot Fig. 284. fibres;—the outermost radiat- ing, whose office is to dilate the pupil—dilatator iridis seu pupil- Ice; the innermost circular and concentric—sphincter iridis seu pupillce—-for the purpose of contracting it. The arrangement of these fibres is represented in Fig. 282, which is an internal view of the human iris magnified three dia- meters ; and Fig. 283, an external view, exhibiting the surface to consist essentially of a plexus of bloodvessels. Both are taken from the microscopic investiga- tions of Mr. Bauer and Sir Eve- rard Home.1 Its structure is now generally admitted to be muscular, and of the non-striated 1 Kolliker2 has recently proved experimentally the existence of a dilator muscle of the pupil. He removed the cornea and the sphincter of the iris of an albino rabbit; and applied feeble galvanic streams to the remaining portion of the iris. Dila- tation of the pupil with convexity of the anterior surface of the iris was the result of repeated experiments. The vessels and nerves of the iris are ramifications of the ciliary,—the nerves arising from the ophthalmic ganglion and nasal branch of the fifth pair. Ber- zelius3 affirms, that the iris has all the chemical characters of muscle. The iris is the coloured part of the eye seen through the transparent cornea; and, according to the particular colours reflected from it, the eye is said to be blue, gray, hazel, &c. In its centre is an opening, called pupil, through which alone the rays of light can reach the lens. This opening can be enlarged or contracted by the contraction or dilatation of the iris; and in this or unstriped variety. Fig. 285. Anterior Segment of a Transverse Sec- tion of the Globe of the Eye seen from within. 1. Divided edge of the three tunics; scle- rotic, choroid (the dark layer), and retina. 2. Pupil. 3. Iris, the surface presented to view in this section being the uvea. 4. Ci- liary processes. 5. Scalloped anterior bor- der of the retina. 1 Lectures on Comparative Anatomy, Lond., 1814:—1828; and Mr. Bauer, Philo- sophical Transactions for 1822, p. 78. 2 Zeitschrift fur Zoologie, vi. 143; and Brit, and For. Med.-Chir. Rev., Jan., 1856, p. 23«. 3 View of the Progress of Animal Chemistry, p. 86, Lond., 1843. ORGAN OF VISION. 69 respect it is perpetually varying, according to circumstances. In man, the pupil is circular; but it differs greatly in its dimensions and shape in different animals. On the posterior surface of the iris—the uvea— pigmentum nigrum exists, as on the choroid. This layer has likewise some effect in giving colour to the eye: in blue eyes, for instance, the tissue of the iris is nearly white,—the pigmentum which appears through it being the chief cause of the coloration. At the point of junction between the iris and choroid coat, they are united to the sclerotica by a band of areolar substance, called ciliary ligament: and from the anterior margin of the choroid, where it unites with the base of the iris, numerous vasculo-membranous appendages arise, which appear to be prolongations of the ante- rior margin of the choroid, turning inwards towards the margin of the crystal- line lens, and terminating abruptly, without being at- tached to that body. They are the ciliary processes. These beautiful appendages are from sixty to eighty in number; and resemble the disk of a radiated flower— corpus ciliare. On their pos- terior surface, they are co- vered by the same kind of pigment as that on the cho- roid and uve*a; and they impart a stain to the mem- branes of the crystalline and vitreous humours. The greatest diversity of opin- ion, here again, exists re- garding both structure and function. By some, the pro- cesses have been esteemed nervous; by others, muscular ;l glandular; and vascular. Sir Everard Home asserts, on the authority of micro- scopic observations by Mr. Bauer,2 that between the processes are bundles of muscular fibres of considerable length, which originate all around from the capsule of the vitreous humour; pass forward over the edge of the lens; are attached firmly to its capsule, and there ter- minate. They are unconnected with the ciliary processes, or iris, and he conceives that their contraction will pull the lens towards the retina. The existence of unstriped muscular fibres in them is confirmed by the observations of Wagner, Todd and Bowman, and others.3 1 Hyrtl, Lehrbuch der Anatomie des Menschen, &c, S. 408, Prag., 1846. 2 Op. citat., and Philosoph. Transact, for 1832, p. 78. s Baly and Kirkes, Recent Advances in the Physiology of Motion, the Senses, Genera- tion, and Developement, p. 25, Lond., 1848. Fig. 286. Choroid and Iris, exposed by turning aside the Sclerotica. c, c. Ciliary nerves branching in the iris. d. Smaller ciliary nerve, e, e. Vasa vorticosa. h. Ciliary ligament and muscle. k. Converging fibres of the greater circle of the iris. I. Looped and knotted form of these near the pupil, with the converging fibres of the lesser circle of the iris within them. o. The optic nerve. 70 SENSIBILITY. Fig. 287. Of late years, the ciliary muscle has been described as a grayish semitransparent ring of non-striated muscular fibres, which covers the outside of the corpus ciliare; and, by its contraction, can draw the ciliary processes forwards, and advance the lens. Dr. Clay Wallace,1 of New York, who was one of the early describers of this muscle, and did the author the favour to demonstrate it to him, is of opinion, that its fibres, when they contract, compress the ciliary veins, and thus produce turgescence of the ciliary processes which occa- sions the movement of the lens. It appears to be the same muscle as the tensor muscle of the Diagram to show the Position choroid—tensor choroideoe—of some anatomists.3 and Action of the Ciliary Such is an anatomical view of the phvsical a. Sclerotic. 6. Cornea, c. Cho- n ,-, n • „____"__c__ roid, separated a little from the part of the eye proper, so far as is necessary lor aaV7?gamUUanad0P^ntthfroCm the physiological inquirer. We have yet to con- which the ciliary muscle ra- s[^er the most important part of the organ ;— diates. e. Ins. n. Lens, con- •Jlv*v" . r r q i g nected with the ciliary processes that which is essentially nervous and vital in bv the anterior wall of the canal . . i i • i 1 „„__„^„„ +„ of Petit, the situation of which its action; and which, as we have seen, goes to 3SdXeteedrsby the *-Mas,lified constitute one of the membranes of the eye- ball—the retina. The optic nerves—second pair of Willis—arise from the anterior part of the optic lobes—corpora quadrigemina3—and not, as was at one time universally believed, from the thalami nervorum opticorum. Setting out from this point, they proceed forwards towards the thalami, to which they adhere; receiving filaments from the corpus geniculatum externum, an eminence a little anterior to, and on the outside of, the corpora; and from a layer of cineritious substance, situate between the point of junc- tion of the nerve of each side and the eminentiae mammillares—called tuber cinereum.4 Proceeding forward towards the eye, the nerves ap- proach, and form a junction at the sella turcica, or on the upper surface of the sphenoid bone. Anterior to this point they diverge,—each passing through the optic foramen to the corresponding eye; piercing the sclerotic and choroid at a point about one-tenth of an inch from the axis of the eye on the side next the nose, where it has a button-like appearance; and expanding to form the whole, or a part of the retina (see page 60). When the optic nerve is regarded from the inside, after removing the retina and choroid, it appears in the form of a circular spot, perforated with small holes, from which medullary matter may be expressed. This is the lamina cribrosa of Albinus. M. Lassaigne has examined the chemical composition of the optic nerve and retina; and concludes, from his experiments, that the retina is formed of the 1 A Treatise on the Eye, p. 53, 3d edit., New York, 1841; and The Accommodation of the Eye to Distances, p. 14, New York, 1850. 2 Ruete, in Wagner's Handwbrterbuch der Physiologie, 16te Lieferung, S. 297, Braun- schweig, 1847; and Todd and Bowman, The Physiological Anatomy and Physiology of Man, Amer. edit., p. 412, Philad., 1850. 3 A pathological case illustrating this origin, by G. Kennion, M. D., is in Lond. Med. Gaz.. Sept., 1838. * riolly, Lond. Med. Gazette, Sept. 24, 1838. ORGAN OF VISION. 71 same elements as the cerebral and Fi£. 288- nervous substance; differing only in the proportion of constituents. It is a question that has often been agitated, whether the optic nerves, at their junction on the sella turcica, sim- ply lie alongside each other, or decus- sate, so that the root of the nerve of the left eye is on the right side, and that of the right on the left. Ana- tomical investigations have, hitherto, left the question unsettled; and patho- logy appears to have furnished proofs on both sides. Thus, where the right eye had been lost for a considerable time, the optic nerve of the same side has been found in a state of atrophy through its whole extent. In other cases of the kind, the posterior portion of the left nerve has been found in this condition.1 Fishes* have the nerve arising from one side of the brain, and passing to the eye of the other side; hence crossing, but not uniting. On the other hand, Vesalius2 gives a plate of a case in which he found the optic nerves passing to the eye of the same side from which they originate, without touching at all; and yet without disturbance of vision. It is not necessary however, to adduce the numerous cases that have been published in favour of the one view or the other. It is impossible to sift those that are entitled to implicit confidence from those that are not. Fig- 289- It may merely be remarked that certain observations of Valsalva, Cheselden,3 and Petit4 appear to show, that where the brain is in- jured, it is the eye of the opposite side that is affected; and, in cases of hemiplegia or paralysis of one side of the body, we certainly have many instances for testing the ac- curacy of this opinion. Somme- ring5—whose correctness as an ob- serving anatomist has never been disputed—affirms, that he had an opportunity of examining seven blind 1 Rudolphi, Grundriss der Physiologie, B. ii. Abth. 1, S. 203, Berlin, 1823. 1 De Corp. Human. Fabric, lib. iv. c. 4. 3 Anatomy of-the Human Body, 13th edit., Lond., 1792. 4 Memoir, de l'Acad., 1723 and 1728. s Blumenbach, Med. Bibl., ii. 2, S. 3b'8; and De Decussatione Nervorum Opticorum, Mogunt., 1786. Optic Nerves, with the origin of seven other Pairs of Nerves. 1, 1. Globe of the eye; the one on the left hand is perfect, but that on the right has the sclerotic and choroid coats removed in order to show the retina. 2. Chiasm of the optic nerves. 3. Corpora albicantia. 4. Infundibu- lum. 5. Pons Varolii. 6. Medulla oblongata. 7. Third pair. 8. Fourth pair. 9. Fifth pair. 10. Sixth pair. 11. Seventh pair. 12. Eighth pair. 13. Ninth pair. Course of Fibres in the Cbiasma, as exhibited by tearing off the superficial bundles from a specimen hardened in spirit. a. Anterior fibres, commissural between the two retina;, p. Posterior fibres, commissural between the thalami. a', p'. Diagram of the preceding. 72 SENSIBILITY. persons, in all of whom the atrophy of the nerve was on the side or root opposite to the eye affected.1 Some, again, have advanced an opinion, that the decussation is par- tial, and concerns only the internal filaments; that the other filaments pass directly on to half the corresponding eye; so that one-half of each eye is supplied by straight fibres proceeding directly from the root of the same side; the other half by those resulting from the decussation of the internal fibres. Messrs. Wollaston,2 Berard, Pravaz,3 Gall and Spurzheim, Cuvier, Serres, Vicq-d'Azyr, Caldani, Ackermann, the brothers Wenzel, G. E. Treviranus, J. Miiller, Kuete,4 and others,5 embrace this opinion for the purpose of explaining the anomaly of vision called hemiopia, in which only one-half the object is seen. MM. Cuvier, Serres, and Caldani assert, that they have noticed the above arrangement in the -nerves of the horse, when subjected to appropriate maceration. Mr. H. Mayo6 states that the optic nerve consists in man of three tracts; the innermost of which is wholly commissural, connecting the two retinae anteriorly, and the optic gan- glia posteriorly. The middle tract decussates, and is considered by him to supply the part of the retina that lies on the inner side of each eyeball, between its anterior border and the entrance of the optic nerve. The external tract, he affirms, does not decussate, but passes on to supply the outer portion of the retina of the same side. Hence, the right optic nerve, in Mr. Mayo's view, supplies the right side of each eyeball; and the left the left. Dr. Wollaston himself was affected with hemiopia; and, in his case, the loss of vision was sometimes on one side, and sometimes on the other; and he thought, that the pheno- mena might be explained by partial decussation of the optic nerves; but Messrs. Solly7 and Mayo have known instances of a like affection involving alternately the centre and circumference of the retina, and therefore not attributable to any such structural arrangement. These views are opposed, also, by the direct experiments of M. Ma- gendie.8 He divided, in a rabbit, the right optic nerve, behind the point of decussation, or what has been called the chiasm of the nerves:— the sight of the left eye was destroyed. On cutting the left root, the sight of the right eye was equally destroyed; and on dividing the bond of union, in another rabbit, by a longitudinal incision, made between the nerves, vision was entirely abolished in both eyes;—a result, which, as he properly remarks, proves not only the existence of decussation, but also that it is total, and not partial as Wollaston had supposed. Another experiment, which he instituted, led to a similar result. Fif- teen days before examining a pigeon he destroyed one eye. The nerve 1 A case elucidative of this point in Lallemand, Sur les Pertes Seminales • and in Dr. Wood's translation in Dunglison's American Med. Library for 1839 v 30 ' ' Philosophical Transact., 1824, p. 222. ' ' 3 Archives Generates de Medecine, Mai, 1825, p. 59. 4 Wagner's Handworterbuch der Physiologie, 16te Lief., S. 297, Braunschweig 1847 6 Hildebrandt's Handbuch der Anatomie, von E. H. Weber, Band. iii. S 438 Braun- schweig, 1832; Blumenbach, op. citat>; Sir D. Brewster's Natural Magic Ame'r edit p. 36, New York, 1833; and Pouillet, Elemens de Physique, iii. 338, Paris 1«W *' 6 London Medical Gazette, Nov. 5, 1841. 7 The Human Brain, its Configuration, &c, p. 263, London, 1836; and Carr>enW« Human Physiology, Amer. edit., p. 24*3, Philada., 1843. «"pemer s 8 Precis, &c, edit, cit., i. 64. ORGAN OF VISION. 73 TO°}120° of the same side, as far as the chiasm, was wasted; and, behind the chiasm, the root of the opposite side. MM. Eolando and Flourens,1 too, found in their experiments, that when one cerebral hemisphere was removed, the sight of the opposite eye was lost. We may con- clude, then, in the present state of our knowledge, that there is not simply a junction, or what the French call adossement, of the optic nerves; but that they decussate at the sella turcica.2 The eye proper receives numerous vessels,—ciliary arteries and veins —and several nervous ramifications,—ciliary nerves—the greater part of which proceed from the ophthalmic or lenticular ganglion. The following are the dimensions, &c, of the organ, on the authority of Petit, Young, Gordon, and Brewster. Eng. inch. Length of the antero-posterior diameter of the eye, . . . . 0*91 Vertical chord of the cornea . . . . . . . .0-45 Versed sine of the cornea ......... (HI Horizontal chord of the cornea ........ 0*47 Size of pupil seen through the cornea .... 0*27 to 0*13 Size of pupil diminished by magnifying power of cornea . 0*25 to 0*12 Radius of the anterior surface of the crystalline ..... 0*30 Radius of posterior surface ......... 0*22 Principal focal distance of lens ........ 1*73 Distance of the centre of the optic nerve from the foramen centrale of Sommering .......... 0*11 Distance of the iris from the cornea ....... (HO Distance of the iris from the anterior surface of the crystalline . . 0*02 Field of vision above a horizontal line .... Field of vision below a horizontal line .... Field of vision in a horizontal plane ..... 150°3 Diameter of the crystalline in a woman above fifty years of age . . 0*378 Diameter of the cornea ......... 0*400 Thickness of the crystalline ........ 0*172 Thickness of the cornea.........0-0421 It is proper to remark, that all these measurements were necessarily taken on the dead organ, in which the parts are by no means in the same relative situation as when alive; and this is a cause why many of the phenomena of vision can never be determined with mathemati- cal accuracy. 3. ACCESSORY ORGANS. The visual organs being of an extremely delicate texture, it was of obvious importance, that they should be guarded against deranging influences. They are accordingly provided with n-umerous parts that afford them protection, and enable them to execute the functions for which they are destined. They are, in the first place, securely lodged in the bony cavities called orbits, which are of a conical figure, with the apices directed inwards. In the truncated apex the foramen op- ticum is situate, by which the optic nerve enters the orbit. Here are, also, superior orbilar and spheno-maxillary fissures, through which many 1 Recherches Experimentales sur le Systeme Nerveux, 2de edit., Paris, 1842. 2 See, on this subject, Adelon, Physioloi»ie de l'Homme, i. 402,2de edit., Paris, 1829, and Bostock's Physiology, edit, cit., p. 709. 3 According to Young, Philos. Transact., P. i. p. 46, Lond., 1801, the field of vision internally is 60°, externally 90°; according to Purkinje, (Rust's Magazin, B. xx. Berlin, 1825,) internally 60°, externally 100°. 4 For the dimensions of different parts of the eye see Krause, in Meckel's Archiv fiir Anatomie und Physiologie fiir 1832; and Longet, Traite de Physiologie, ii. 41, Paris, 1850. 74 SENSIBILITY. vessels and nerves proceed to the eye and its appendages. The base of the orbits is not directly opposite the apices, but tends outwards; so that the axes of these cavities, forming an angle of about 90° with each other, if prolonged, would meet at the sella turcica. The eye, however, is not placed in the direction of the axis of the orbit, but straight forward; and as it is nearly spherical, it is obvious that it cannot completely fill the conical cavity. In Fig. 290, muscles 9 and 13 indicate the shape of the upper and lower surfaces of the cavities;— the whole of the space between the posterior part of the orbit and the muscles, which is not occupied by the optic nerve, being occupied by an adipous areolar tissue, on which the eye is placed as it were on a cushion. Under special morbid circumstances, this deposit becomes greatly augmented, so as to cause the eye to start from its socket,— constituting the disease called exophthalmos. The parts, however, that are more immediately reckoned amongst the protectors of the organ—tutamina oculi—are the eyebrows, eyelids, and lachrymal apparatus. The eyebrows or supercilia are situate imme- diately on the superciliary ridge of the frontal bone. They consist of hair, varying in colour according to the individual, and turned to- wards the outer angle of the eye; of common integument; sebaceous follicles, situate at the root of each hair; and muscles to move them,— namely, the frontal portion of the occipito-frontalis, the upper edge of the orbicularis palpebrarum, and the corrugator supercilii. The pal- pebral or eyelids are, in man, two in number, an upper and a lower, or a greater and a less,—palpebra major seu superior, and palpebra mihor seu inferior,—the former covering three-fourths of the eye; hence the transverse diameter of the organ is not represented by their union,— the latter being much below it, and therefore improperly termed, by Haller, cequator oculi. By the separation of the eyelids, we judge, but inaccurately, of the size of the eye,—one, who is capable of separating them largely from each other, appearing to have a large eye;—and conversely. The edge of the eyelids is thick, rounded, and furnished with hairs, which resemble generally, in colour, those of the head. These are the eyelashes or cilia. On the upper eyelid they are curved upwards; on the lower downwards. The eyelids are formed of four membranous layers in superposition; and of a fibro-cartilage, which extends along the whole edge, and keeps them tense. The outermost of these layers is the common integument, the skin of which is delicate and semitrans- parent, yielding readily to the motions of the eyelids, and having nu- merous transverse folds. The areolar tissue beneath the skin is very loose; and, under particular circumstances, is infiltrated by a serous fluid, which gives the eyelids, especially the lower, a dark appearance; but they never contain fat. Beneath the common integument is the muscular stratum, formed, in the lower eyelid, by the orbicularis pal- pebrarum; in the upper, by the same muscle, and the levator palpebral superiors, (Fig. 290,) which arises from above the foramen opticum and is inserted into the superior edge of the fibro-cartilage of the tarsus. Beneath the orbicularis palpebrarum, again, is a fibrous layer which occupies the whole of the eyelids, passing from the edo-e of the orbit to the tarsal margin, and seeming intended to limit the motion of the eyelids, when they approximate each other. The last layer ACCESSORY ORGANS OF VISION. 75 and that which forms the posterior surface of the eyelids, is a fine, delicate, transparent, mucous membrane, called tunica conjunctiva or tunica adnata; so named because it joins the eyelids to the globe of the eye. It lines, in fact, the eyelids, and is reflected over the ball; but it has been a matter of contention whether it passes over the trans- parent cornea. The generality of anatomists sa}7 it does; M. Ribes,1 however, maintains the opinion, that it extends only as far as the cir- cumference of the cornea, and that the cornea itself is covered by a proper membrane. Physiologically, this dispute is of no "moment. At its outer surface, a humour is constantly exhaled, which keeps it moist, and facilitates the motions of the eyelids over the eyeball. Its loose state also favours these motions. Both eyelids are kept tense by the aid of a fibro-cartilage, situate along the edge of each, and called tarsus. That of the upper is much more extensive than that of the lower; and both seem as if cut obliquely at the expense of their inner surface; so that, in the opinion of most anatomists, when the eyelids are brought together, a triangular canal is formed between them and the ball of the eye, which has been conceived useful in conducting the tears towards the lachrymal puncta. M. Magendie2 denies that any such canal exists: and there seems little evidence of it, when we examine how the tarsal cartilages come in con- tact. Such a canal, destined for the purposes mentioned, would seem superfluous. Be- ' sides the eyelashes, certain compound glands or follicles, called Meibomian, are situate in the sub- stance of the tarsal cartilages. They are thirty or forty in number in the upper eyelid; and twenty-five or thirty in the lower, are in par- ticular furrows between the tarsal fibro-cartilages and the conjunctiva, and secrete a sebaceous fluid, called by the French chassie, when in the dry state; by the Germans, Augenbutter, ("eyebutter,") and by us, gum of the eye. It serves the purposes of follicular secretions in general. The arrangement of the eyelids differs in different animals. In several, both move; but, in others, only one; either the lower rising to join the upper, or the upper descending to meet the lower. In the sunfish—tetraodon mola—the eyelid is single and circular, with a per- foration in the centre, which can be contracted or enlarged, according to circumstances. In many animals there is a third eyelid, called 1 Memoires de la Societe Medioale d'Emulation, vol. vii., Paris, 1817. 2 Precis Elementaire, i. 52. Fig. 290. Muscles of the Eyeball. 1. A small fragment of the sphenoid bone around en- trance of optic nerve into orbit. 2. Optic nerve. 3. Globe of eye. 4. Levator palpebra muscle. 5. Supe- rior oblique muscle. 6. Its cartilaginous pulley. 7. Its reflected tendon. 8. Inferior oblique muscle ; the small square knob at its commencement is a piece of its bony origin broken off. 9. Superior rectus. 10. Internal rec- tus almost concealed by optic nerve. 11. Part of ex- ternal rectus, showing its two heads of origin. 12. Ex- tremity of external rectus at its insertion ; the interme- diate portion of muscle having been removed. 13. Inferior rectus. 14. Tunica albuginea formed by ex- pansion of tendons of four recti. 76 SENSIBILITY. Meibomian Glands seen from the Inner or Ocular Surface of the Eyelids, with the Lachrymal Gland—of the Right Side. a. Palpebral conjunctiva. 1 Openings of lachrymal ducts. 6. Meibomian glands. inferior or depressor. ternus or abductor. Lachrymal gland. 2. 3. Lachrymal puncta. nictitating membrane, which is of a more delicate texture and more largely supplied with bloodvessels; and in some animals is transpa- rent. In birds it exists, and is 291* well seen in the owl. It is at the inner angle of the eye; and is capable of being drawn over the ball like a curtain by two special muscles, and of thus freeing the surface of the eye from extraneous substances. In man, it is only a vestige, des- tined to no apparent use. It is called valvula or plica semilu- naris. The eye has its proper mus- cles, capable of moving it in various directions. Their ar- rangement is readily under- stood. They are six in num- ber :—four recti or straight mus- cles; and two oblique. 1. Rectus superior or levator. 2. Rectus 3. Rectus internus or adductor; and 4. Rectus ex- All arise from the base of the orbit, around the optic foramen; pass forward to vanish on the sclerotica; and, according to some anatomists, extend over, and form a layer to, the cornea. The oblique muscles are—1. Greater oblique, obliquus superior, patheticus or trochlearis, which arises from the inner side of the foramen opticum; passes for- wards to the internal orbitar process of the frontal bone, where its tendon is reflected over a pulley or trochlea, and crosses the orbit to be inserted into the upper, posterior, and outer part of the globe of the eye. 2. Lesser oblique or obli- quus inferior, whose fibres arise from the anterior and inner part of the floor of the orbit, near the lachrymal groove* pass under the eyeball, and are inserted between the entrance of the optic nerve and insertion of the abductor oculi, and opposite the insertion of the obliquus supe- The thirdpair~mo- View of the Third, Fourth, and Sixth Pairs of Nerves. 1. Ball of the eye and rectus externus muscle. 2. Superior maxilla. 3. Third pair, distributed to all the muscles of the eye except the superior oblique and ex- ternal rectus. 4. Fourth pair, going to the superior oblique muscle. 5. One of the branches of the seventh pair. 6. Sixth pair, distributed to the external rectus muscle. 7. Spheno-palatine ganglion and branches. 8. Ciliary nerves from the lenticular ganglion, the short root of which is seen to connect it with the third pair. rior. These muscles have their proper nerves. ACCESSORY ORGANS OF VISION. 77 tores oculorum or common oculo-muscular—are distributed to all the muscles except the trochlearis and abductor; the fourth pair or pathetic or internal oculo-muscular, to the trochlearis singly; and the sixth pair or external oculo-muscular, to the abductor. Posterior View of the Eyelids and Lachrymal Gland. 1, 1. Orbicularis palpebrarum muscle. 2. Borders of the lids. 3. Lachrymal gland. 4. Its ducts opening in the upper lid. 5. Conjunctiva covering the lids. 6. Puncta lacrymalia. 7. Lachrymal caruncle as seen from behind. Lachrymal Canals. 1. Puncta lacrymalia. 2. Cul-de-sac at the orbital end of the canal. 3. Course of each canal to the saccus lacrymalis. 4, 5. Saccus lacrymalis. 6. Lower part of the ductus ad nasum. The office of tutamina oculi is not wholly engrossed by the parts that have been mentioned. The apparatus for the secretion of the tears participates in it, by furnishing a fluid, which lubricates the surface of the eye, and keeps it in the necessary degree of humidity for the proper performance of its functions. It is a beautiful, and ingenious little apparatus; the structure of which can easily be made intelligible. It consists of the lachrymal gland; the excretory ducts of the gland; the caruncula lacrymalis; the lachrymal ducts; and the nasal duct; in other words, of two sets of parts,—one, forming the fluid and pouring it on the anterior surface of the eye; the other comprising the organs for its excretion. The lachrymal gland is situate in a small fossa or depression at the upper, anterior, and outer part of the orbit. It is an oval body of the size of a small almond ; of a grayish colour; and com- posed of small, whitish, granular bodies collected into lobes. From these, six or seven excretory ducts arise, which run nearly parallel to each other, and open on the inner side of the upper eyelid, near the outer angle of the eye and the tarsal cartilage. Through these ducts, the tears, secreted by the lachrymal gland, are spread over the tunica conjunctiva. They are not secreted by animals that live in water. At the inner angle of the eye is the caruncula lacrymalis. It is a collection of small mucous follicles, which secrete a thick, whitish humour, to fulfil a similar office with the secretion of the Meibomian follicles. It completes the circle formed by those follicles around the eyelids. The rosy or pale colour of the body is supposed to indicate strength or debility. This it does, like other vascular parts of the system, and in a similar manner. The puncta lacrymalia are two 78 SENSIBILITY. small orifices, situate near the inner angle of the eye; the one in the upper; the other in the lower eyelid, at the part where the eyelids quit the globe to pass round the caruncula lacrymalis. They are con- tinually open, and directed towards the eye. Each punctum is the commencement of a lachrymal duct, which passes towards the nose in the substance of the eyelids, between the orbicularis palpebrarum and tunica conjunctiva. These open, as represented in Fig. 294, into the lachrymal sac, which is nothing more than the commencement of the nasal duct or ductus ad nasum. The bony canal is formed by the ante- rior half of the os unguis, and by the superior maxillary bone, and opens into the nose behind the os spongiosum inferius. Through these excretory ducts, all of which are lined by a prolongation of mucous membrane, the tears pass into the nasal fossae. Dr. Horner1 has best described a small muscle, which is evidently a part of the lachrymal apparatus, and to which he gives the name tensor tarsi. It is on the orbital face of the lachrymal sac; arises from the superior posterior part of the os unguis; and, after having advanced a quarter of an inch, bifurcates; one fork being inserted along each lachrymal duct, and terminating at or near the punctum. It is pro- bable, that the function of this muscle is to keep the punctum properly directed towards the eyeball; or, as Dr. Physick suggested, to keep the lids in contact with the globe. The office, assigned to it by Dr. Horner, of enlarging, by its contraction, the cavity of the lachrymal sac, and thus producing a tendency to a vacuum—which vacuum can be more readily filled through the puncta than through the nose, owing to the valves or folds of the internal membrane of the sac—is inge- nious, but apocryphal. The tensor tarsi muscle is now commonly associated with the name of Horner2—" muscle of Horner."3 4. PHYSIOLOGY OF VISION. The preceding anatomical sketch will enable the reader to compre- hend this important organ in action. In describing the office executed Fig. 295. Scheme of the Progress of Luminous Rays through the Eye 1 Lessons in Practical Anatomy, 3d edit., p. 116, Philad., 1836 ; and General Ana tomy and Histology, 8th edit., ii. 394, Philad., 1851. Also, Rosenmiiller's Hanrlhn^ der Anatomie, dritte Auflage, Leipz., 1819. T. W. Jones, art. Lachrymal Organs, Cyclop, of Anat. and Physiol., Julv 1840 See M. Sappey, Researches on the shape, size and weight of the globe of the'* in Memoires de la Soeiete de Biologie, annee 1854, p. 231, Paris 1855. eye, PHYSIOLOGY OF VISION. 79 by its various components, we shall follow the order there observed, premising some general considerations on the mechanism of vision; and afterwards depict the protecting and modifying influences exerted by the various accessory parts:—the different phenomena of vision will next be explained; and, lastly, the information conveyed to the mind by this sense. In tracing the progress of luminous rays through the purely physical part of the organ, we shall, in the first instance, suppose a single cone to proceed from a radiant point in the direction of the axis of the eye; or, in other words, of the antero-posterior diameter of the organ, B b. It is obvious, that the rays which fall upon the transparent cornea can alone be inservient to vision. Those that impinge upon the scle- rotica are reflected; as well as a part of those that fall upon the cornea, giving occasion, in the latter case, to the image observed in the eye, and to the brilliancy of the organ. Nor does the whole of the cornea admit rays, for it is commonly more or less covered, above and below, by the free edge of the eyelids. Again: the whole of the light, that enters the cornea, does not impinge upon the retina. A portion falls upon the iris, and is reflected back to the eye, in such manner as to give us the notion of the colour of the organ. It is, consequently, the light, which passes through the pupil, that can alone attain the retina. Some interesting points of diagnosis are connected with the reflection which takes place from the humours of the eye. If a lighted candle be held before an eye the pupil of which has been dilated by belladonna, and in which there is no obscurity in the humours or their capsules, three distinct images of the flame are perceptible—situated one behind the other. Of these images the anterior and the posterior are erect; the middle inverted. The anterior is the brightest and most distinct; the posterior the least so. The middle one is the smallest, but it is bright. The anterior erect image is produced by the cornea; the pos- terior by the anterior surface of the lens; and the middle or inverted image by the concave surface of the capsule of the crystalline. M. Sanson proposed this catoptric method of examining the eye as a means of diagnosis between cataract and amaurosis,—in the latter all the images being seen; and experience has shown it to be a valuable mode of investigating various conditions of the eye, which might not be readily understood without its agency.1 If we suppose a luminous cone to proceed from a radiant point B, Fig. 295, directly in the prolongation of the antero-posterior diameter of the eye, the axis of this cone will also be the axis of the organ; so that a ray of light, impinging upon the humours in the direction of the axis, as in the case of the lenses previously referred to, will pass through the humours without undergoing deflection, and will fall upon the re- tina at b. This, however, is not the case with the other rays composing the cone. They do not fall perpendicularly upon the cornea; and are, 1 Gazette Medicale de Paris, 27 Janvier, 1844. See, also, T. Wharton Jones, The Principles and Practice of Ophthalmic Medicine and Surgery, Amer. edit., p. 39, Philad., 1847 ; Lawrence, Treatise on Diseases of the Eye, Amer. edit., by Dr. Hays, p. 93, Philad., 1854; and Mackenzie, Practical Treatise on Diseases of the Eye, Amer. edit., by Dr. A. Hewson, p. 705, Philad., 1855. 80 SENSIBILITY. consequently, variously refracted in their passage through the cornea, aqueous humour, crystalline, and vitreous humour; but in such a man- ner that they join their axis in a focus at a point where it strikes the retina. The transparent parts of the eye, as has been seen, are of different densities, and consequently possessed of different refractive powers. These powers it has been attempted to estimate; and the following is the result of the slightly discordant evaluations of different experi- menters;—the power of air being 1*000295. Cornea. Aqueous Humour. CRYSTALLINE LENS. Vitreous Humour. Capsule. Outer Layers. Centre. Mean. Hawksbee . . Jurin .... Rochon . . . Young . . . Chossat . . . Brewster . . 1*339 1*33595 1*3333 1*329 1*3333 1*338 1*3366 1*339 1*3767 1*338 1*393 1*3990 1*384 1*3839 1*33595 1*332 1*339 1*3394' A ray of light impinging obliquely on the surface of the transparent cornea passes from a rarer to a denser medium. It will, consequently, be refracted towards a perpendicular raised from the point of impact. From this cause, as well as from the convexity of the cornea, it will be rendered more convergent; or, in other words, approach the axis of the cone. In proceeding through the aqueous humour, little variation will be produced, as the densities of it and the cornea differ but little; the latter is slightly more refractive, according to the table; and there- fore the tendency will be to render the ray less convergent. This convergence gives occasion to the passage of a greater number of rays through the pupil; and necessarily adds to the intensity of the light that impinges on the crystalline. Pursuing the ray through the two chambers of the eye, we find it next impinging on the surface of the crystalline, which possesses a much higher refractive power than the cornea or aqueous humour; in the ratio of 1*384 to 1'336. From this cause, and from the convexity of the anterior surface of the lens, the ray is rendered still more convergent or approaches still more the'axis of the cone. It is probable, however, that even here some of the lio-ht is reflected back; and goes towards the formation of the imao-e in the eye, and the brilliancy of the organ; other reflected rays°perhaps impinge upon the pigmentum nigrum lining the posterior surface of the iris, and are absorbed by it. From the crystalline the ray emerges into a medium possessing less refractive power; and therefore it° is deflected from the perpendicular.' The shape, however,'of the posterior surface of the lens so modifies the perpendiculars, as to occasion such a degree of convergence, that the oblique ray meets the axis at a focus on the retina. (See Figs. 261 and 295.) In this manner two cones are formed; one having its apex at the radiant point, and its base on the 1 For the measurements of M. Vallee, see his Theorie de l'CEil, p. 20 Pari* l S4Q . ™ Longet, Traite de Physiologie, ii. 42, Paris, 1650. ' ' b4d ' or VISION—INVERTED IMAGE. 81 cornea—the objective cone;—the other having its apex on the retina, and termed the ocular cone. These remarks apply chiefly to the cone proceeding in the direction of the axis of the different humours, from a single radiant point. It is easy to understand, that every portion of the object ABC, Fig. 295, must be a radiant point, and project so many cones in an analogous manner, which, by impinging upon the retina, form a picture of the object upon that expansion, at g b h. It is important, however, to observe, that the rays proceeding from the upper part of the object fall, after refraction, upon the lower part of the retina; and those from the lower part of the object upon the upper; so that the picture or representation of the object on the retina must be inverted. How the idea of an erect object is excited in the mind will be the subject of after inquiry. When rays, as A g and C h, fall obliquely on a lens, and pass through its centre, they suffer refraction at each of its surfaces; but as the two refractions are equal, and in opposite directions, they may be esteemed to pursue their course in a straight line. The point a, at which these various rays cross, is called the optic centre of the crystal- line. Each of the straight rays proceeding from a radiant point may be assumed as the axis of all the rays proceeding obliquely from the same point; and the common focus must fall on some part of this axis. In 'this way the object is represented in miniature, and inverted, on the retina. As, however, the oblique ray has to pass through the cornea and aqueous humour, before it impinges on the crystalline, it undergoes considerable deflection; and consequently it is not accurate to represent it as pursuing a straight course through the different humours on its way to the retina. The main deflection—as in the case of the rays D t s, and B t r, Fig. 295—occurs at the entrance of the rays into the cornea. That an inverted representation of external objects is formed within the eye is in accordance with sound theory; and is supported not only by indirect, but by direct experiment. If a double convex lens be fitted into an opening made in the window-shutter of a darkened chamber, luminous cones will proceed from the different objects on the outside of the house, and converge within; so that if they be received on a sheet of paper, a beautiful and distinct image of the object will be Fig. 296. Camera Ohscura. apparent. This is the well-known instrument, the camera obscura, of which the organ of sight may be regarded as a modification. Making abstraction, indeed, of the cornea, and of the aqueous and vitreous VOL. II.—6 82 SENSIBILITY. humours, the representation of the eye in Fig. 295, with the object, ABC and its image on the retina, is the common camera obscura. The eye is, therefore, more complicated and more perfect than this simple instrument: the cornea, with the aqueous and vitreous humours, is added for the purpose of concentrating the light on the retina; the latter, in addition, affording a large space for the expansion of the retina, and preventing the organ from collapsing. In the operation for cataract by extraction, which consists in removing the lens through an opening made in the lower part of the cornea, the aqueous humour escapes, but is subsequently regenerated. If, however, too much pres- sure be exerted on the ball, to force the crystalline through the pupil and the opening in the cornea, the vitreous humour is sometimes pressed out, when the eye collapses, and is irretrievably lost. Experiments have been instituted on this subject, the results of which are even more satisfactory than the facts just mentioned. These have been of different kinds. Some experimenters have formed arti- ficial eyes of glass, to represent the cornea and crystalline, with water in place of the aqueous and vitreous humours. Another mode has been to place the eye of an ox or a sheep in a hole in the shutter of a dark chamber, having previously removed the posterior part of the sclerotica so as to permit the images of objects on the retina to be dis- tinctly seen. Malpighi and Haller employed a more easy method. They selected the eyes of the rabbit, pigeon, puppy, &c, the choroid of which is nearly transparent; and, directing the cornea towards luminous objects, they saw them distinctly depicted on the retina. M. Magendie1 repeated these experiments by employing the eyes of albino animals, as those of the white rabbit, white pigeon, white mouse, &c, which afford great facilities,—the sclerotica being thin, and almost transparent; the choroid, also, thin, and when the blood, which gives it colour, has disappeared after the death of the animal, offering no sensible obstacle to the passage of light. In every one of these ex- periments, external objects were found to be represented on the natural or artificial retina in an inverted position ; the image being clearly defined, and with all the colours of the original. Yet how minute must these representations be in the living eye; and how accurate the mental appreciation,—seeing, that each impression from myriads of luminous points is transmitted by the retina to the encephalon, and perceived with unerring certainty I In the prosecution of his experiments—in some of which he was assisted by M. Biot—M. Magendie found, as might have been expected, that any alteration in the relative proportion or situation of the dif- ferent humours had a manifest effect upon vision. When a minute opening was made in the transparent cornea, and a small quantity of the aqueous humour permitted to escape, the image had no longer the same distinctness. The same thing occurred when a little °of the vitreous humour was discharged by a small incision made through the sclerotica. He farther found, that the size of the image on the retina was proportionate to the distance of the object from the eye. When the whole of the aqueous humour was evacuated, the image seemed to 1 Precis Elementaire, i. 70. VISION—EYE ACHROMATIC. 83 occupy a greater space on the retina, and to be less distinct and lumi- nous ; and the removal of the cornea was attended with similar results. When the crystalline was either depressed or extracted, as in the ope- ration for cataract, the image was still formed at the bottom of the eye; but it was badly defined; slightly illuminated, and at least four times the usual size. Lastly,—when the cornea, aqueous humour, and crys- talline were removed, leaving only the capsule of the crystalline and the vitreous humour, an image was no longer formed upon the retina: the light from the luminous body reached it, but it assumed no shape •similar to that of the body from which it emanated. Most of the results—as M. Magendie1 remarks—accord well with the theory of vision. Not so, the distinctness of the image under these deranging circumstances. According to the commonly received notions on this subject, it is necessary, in order to have the object depicted with distinctness on the retina, that the eye should accommodate itself to the distance at which the object is placed. This is a subject, how- ever, that will be discussed presently. Such are the general considerations relating to the progress of lumi- nous rays from an object through the dioptrical part of the organ of sight to the nervous portion—the retina. We shall now inquire into the offices executed by such of the separate parts that enter into its composition as have not already engaged attention. We have shown, that the cornea, aqueous humour, crystalline, and vitreous humour, are a series of refractive bodies, to concentrate the luminous rays on the retina; to keep the parietes of the eye distended; and to afford surface for the expansion of the retina;—thus enlarging the field of vision. It is probably owing to their different refractive powers, that the eye is achromatic; or, in other words, that the rays, impinging upon the retina, are not decomposed into their constituent colours,—an inconvenience which appertains to the common lens (page 57). The eye is strictly achromatic; and it has been an object of earnest inquiry amongst philosophers to determine how the aberration of refrangibility is corrected in it. Euler,2 first perhaps, asserted, that it is owing to the different refractive powers of the humours; and he conceived, that, by imitating this structure in the fabrication of lenses, they might be rendered achromatic. Experience has shown the accu- racy of this opinion (Fig. 265). Others have believed, that the effect is produced by certain of the humours—as the aqueous and vitreous— which they have considered capable of correcting the dispersion pro- duced by the cornea and crystalline. Others have placed it in the crystalline, the layers of which being of different dispersive powers may correct each other; whilst others, again, have ascribed it to the iris acting as a diaphragm, and thus preventing the rays of light from falling near the margin of the lens.3 Lastly;—some have denied alto- gether the necessity for the eye's being achromatic; asserting, that the depth of the organ is so inconsiderable, that the dispersion of the rays, 1 Precis Elementaire, i. 73. 2 Mem. Berlin, p. 279, pour 1747 ; and Letters of Euler, by Sir D. Brewster, Amer. edit., i. 163, New York, 1833. 3 M. De Haldat, Optique Oculaire, suivi d'un Essai sur rAchromatismo de l'OEil, p. 79, Paris et Nancy, 1849. 84 SENSIBILITY. by the time they reach the retina, ought to be inappreciable. This was the opinion of M. D'Alembert. Dr. Maskelyne1 calculated the amount of the aberration, that must necessarily take place in the eye, and con- cluded that it would be fourteen or fifteen times less than in a common refracting telescope; and therefore imperceptible. Uncertainty still rests on this subject; and it cannot be removed until the dispersive and refractive powers of the transparent parts of the organ as well as their exact curvatures shall have been mathematically determined. It has been already shown, that the data we possess on this subject from different observers are sufficiently imprecise. Our knowledge, then, is restricted to the fact, that the eye is per- fectly achromatic; and that, in this respect, it exceeds any instrument of human construction. The views of Euler are the most probable; and the effect is doubtless much aided by the iris or diaphragm, which prevents the rays from falling upon the margins of the lens, where, by the surfaces meeting at an angle, the aberration must necessarily be greatest. Of the coats of the eye,—the sclerotic gives form to, and protects the organ. The choroid is chiefly useful by the black pigment, which lines and penetrates it. It will be seen that some individuals, on insufficient grounds, have esteemed it the seat of vision. Leaving this question for the moment, and granting, as we shall endeavour to establish, that the impression is received upon the expansion of the optic nerve—the retina,—the use of the choroid would seem to be, in ordinary circum- stances, to afford surface for the pigmentum nigrum, whose function it is to absorb the rays after they have passed through the retina; and thus to obviate the confusion, that would arise from varied reflections, were the choroid devoid of such dark covering. In albinos or white animals, in which the pigment is wanting, this inconvenience is really experienced; so that they become nyctalopes, or, at least, see but im- perfectly during the day. In the night, or when the light is feeble, their vision is unimpaired; hence the albinos of our species have been called by the Germans and Dutch, Kakerlaken or cockroaches. Sir Everard Home2 is of opinion, that the pigmentum nigrum is provided as a defence against strong light; and that, hence, it is lightest in those countries least exposed to the scorching effects of the sun. In con- firmation of this, he remarks, that it is dark in the monkey, and in all animals that look upwards, and in all birds exposed to the sun's rays; whilst the owl, that never sees the sun, has no black pigment. It doubtless possesses the function assigned to it by Sir Everard. The use of the shining spot on the outside of the optic nerves of quadrupeds, called tapetum, has been an interesting theme of specula- tion; and has given rise to much ingenious, and to not a little ridicu- lous, hypothesis amongst naturalists. The absence of the black pig- ment necessarily occasions the reflection of a portion of the rays from the membrana Ruyschiana; and it has been presumed, that these 1 Philosophical Transactions for 1789, lxix. 256. 2 Lectures on Comparative Anatomy, iii. 220, Lond., 1823. VISION—PHYSIOLOGY OF THE COATS OF THE EYE. 85 reflected rays, in their passage back through the retina, may cause a double impression, and thus add to the intensity of vision. Another view has been, that the reflected rays may pass outwards through the retina without exciting any action, to be thrown on the object in order to increase the distinctness of the image on the retina, by an in- crease of its light. Dr. Fleming,1 who usually exhibits much philo- sophical acumen, and physiological accuracy, thinks it not probable, that both surfaces of the retina are equally adapted for receiving im- pressions of external objects, and is of opinion, that the rays, in their passage inwards, alone produce the image. M. Desmoulins2 has, how- ever, adduced many facts and arguments to show, that the tapetum really does act the part of a mirror; and, by returning the rays through the retina, subjects it to a double contact. He affirms, that in nocturnal animals, and in many fishes and birds, which require certain advantages to compensate for the conditions of the media in which they are situate, the tapetum is of great extent, and always cor- responds to the polar segment of the eyeball or to the visual axis;— that in many animals, as in the cat, the pigment is wholly wanting; and that it is only necessary for the vision of diurnal animals. He farther remarks, that, in man, it diminishes according to age, and in advanced life becomes white; and he ingeniously presumes, that this is a means employed by nature to compensate, in some measure, for the gradual diminution of the sensibility of the retina,—the choroid beneath reflecting more and more of the rays in proportion as the pig- ment is removed from its surface. The views of M. Desmoulins are the most satisfactory of any that have been propounded, and they are corroborated by the experiments of Gruithuisen, Esser, and Tiedemann,3 which show, that the luminous phenomena never occur in the eyes of nocturnal animals when light is totally excluded. Gruithuisen observed it in the dead as well as the living animal. Tiedemann perceived it in a cat, which had been de- capitated for twenty hours; and it did not cease until the humours had become turbid. The views of these observers impress us the more forcibly, when we compare them with certain fanciful speculations,— as that of M. Richerand,4 who supposes, that the use of the tapetum is to cause animals to have an exaggerated opinion of man! As if the same exaggerated opinion would not be produced whatever were the object that impressed the organ. The iris has been compared, more than once, to the diaphragm of a lens or telescope. Its function consequently must be,—to correct the aberration of sphericity, which would otherwise take place. This it does by diminishing the surface of the lens on which the rays impinge, so that they meet at the same focus on the retina. M. Biot has re- marked, that this diaphragm is situate in the eye precisely at the place where it can best fulfil the office, and yet admit the greatest possible quantity of light. 1 Philosophy of Zoology, i. 192, Edinb., 1822. 2 Magendie's Journal de Physiologie, iv. 89. s Traite Complet de Physiologie de l'Homme, &c, traduit par A. J. L. Jourdan, p. 550. 4 Adelon, Physiologie de l'Homme, 2de edit., i. 443. See, also, Sir E. Home's Lec- tures on Comp. Anat., iii. 243. 86 SENSIBILITY. The iris is capable of contracting or dilating, so as to contract or dilate the pupil. It has been already observed, that the views of ana- tomists regarding the muscular structure of the iris have been discre- pant; and that some esteem it to be essentially vascular and nervous, the vessels and nerves being distributed on an erectile tissue. The partisans of each opinion explain the motions of the iris differently. They who admit it to consist of muscular fibres affirm, that the pupil is contracted by the action of the circular fibres, and dilated by that of the radiated. Those, again, that deny the muscularity of the organ say, that contraction of the pupil is caused by the afflux of blood into the vessels, or by a sort of turgescence similar to what occurs in erec- tile parts in general; and dilatation, by the withdrawal of the surplus fluid. Admitting—and this must now be conceded—that the iris is really muscular, we meet with the singular anomaly in its physiology—that no ordinary stimulus, applied directly to it, has any effect in exciting it to contraction. It may be pricked with the point of a cataract needle without the slightest motion being excited; and, from the experiments of Fontana1 and Caldani,2 it seems equally insensible when luminous rays are made to impinge upon it; yet MM. Fowler, Rinhold, and Nysten3 have proved, that it contracts like other mus- cular parts on the application of the galvanic stimulus. Like them, too, it is under the nervous influence,—its movements being generally involuntary; but, there is some reason to believe, occasionally volun- tary. Dr. Roget asserts, that this is the case with his own eye.4 In the parrot, and certain nocturnal birds, its motions are manifestly in- fluenced by volition;5 and when the cat is roused to attention, the pupil dilates, so as to allow a greater quantity of light to reach the retina. M. Magendie6 affirms, that the attention and effort required to see minute objects distinctly occasion contraction of the human pupil. He selected an individual whose pupil was very movable; and placing a sheet of paper in a fixed direction as regarded the eye and light, he marked the state of the pupil. He then directed the person to endeavour, without moving the head or eyes, to read very minute characters traced on the paper. The pupil immediately contracted, and continued so, as long as the effort was maintained. Many experiments have been made to discover the nerve, which presides over the movements of the iris. These experiments have demonstrated, that if, instead of directing a pencil of rays upon the iris, we throw it on the retina, or through the retina on the choroid, contraction of the pupil is immediately induced. The movements of the iris must, then, be to a certain extent under the influence of the optic as an afferent nerve. It is found, indeed, that if the optic nerve be divided on a living animal, the pupil becomes immovable and ex- panded. Yet, that the motions of the iris are not solely influenced by this nerve is evinced by the fact, that in many cases of complete 1 Dei Moti dell' Iride, cap. i. p. 7, Lucca. 1765. 2 Institutiones Physiological, &c, Lips., 1785. » Magendie Ibid i 75 4 Outlines of Physiology, Amer. edit., by the Author, p. 286, Philad.' 1839*' 5 Mayo, Outlines of Physiology, 4th edit., p. 286, Lond., 1837. 6 Precis Elementaire, 2de 6dit., i. 74. VISION—ACTION OF THE IRIS. 87 amaurosis of both eyes, there has been the freest dilatation and con- traction of the pupil; and also, that section of the nerve of the fifth pair, which chiefly supplies the iris, equally induces immobility of the pupil. The same effect is produced, according to Mr. Mayo,1 by di- viding the third pair. If the trunk of that nerve be irritated, con- traction of the pupil is seen to follow; and, according to Desmoulins,3 in the eagle, whose iris is extremely movable, the third is the only nerve distributed to the organ. The general remark, made by M. Broussais3 on the organs that combine voluntary and involuntary func- tions, has been considered applicable here;—that they will be found to possess both cerebral and ganglionic nerves. Accordingly, M. Magen- die4 conjectures, that those of the ciliary nerves, which proceed from the ophthalmic ganglion, preside over the dilatation of the pupil, or are the nerves of involuntary action; and that those which arise from the nasal branch of the fifth pair preside over its contraction. We might thus understand why, in apoplexy, epilepsy, &c, the pupil should be immovably dilated. All volition and every cerebral pheno- menon are abolished by the attack: the nerve of the fifth pair, there- fore, loses its influence; and the iris is given up to the agency of the ganglionic nerves or nerves of involuntary action proceeding from the ophthalmic ganglion. On the whole, our notions regarding the motions of the iris, and the nerves that preside over them, must be esteemed vague and unsa- tisfactory ; and the obscurity is not diminished by a remark of Bellin- geri.s The iris, he observes, derives its nerves from the ophthalmic ganglion, which is formed by the fifth in conjunction with the third pair; and its involuntary motions, he thinks, are regulated by the fifth pair* In those instances, in which the motions of the iris have been found dependent on the will, Bellingeri argues, that the ciliary nerves received no branches from the fifth—a fact, which has been proved by dissection, as well as by the circumstance, that in the parrot, owl, and the ray genus among fishes, in which the iris is under the will of the animal—there is no ophthalmic ganglion. The most recent, and most probable view is, that the annular fibres contract, so as to diminish the size of the pupil under the influence of the third pair; whilst the contraction of the radiating fibres and consequent dilatation of the pupil is under the cervical portion of the great sympathetic. Messrs. Budge and W^aller6 found, that such contraction was induced by irri- tating the nerve in the neck by the magneto-electric apparatus; whilst a permanent contraction of the pupil was induced by a division of the nerve,—the action of the third pair being no longer antagonized. The iris contracts or dilates according to the intensity of the light that strikes the eye. If the light from an object be feeble, the pupiL 1 Commentaries, P. ii. p. 5, and Outlines of Human Physiology, &c, 4th edit., p. 287, Lond., 1837. 2 Anatom. des System. Nerveux, Paris, 1825. 3 Traite de Physiologie appliquee a, la Pathologie, translated by Drs. Bell and La Roche, 3d edit., p. 77, Philad. 1833. « Precis, &c, ed. cit., i. 77. 5 Dissert. Inaugural. Turin, 1823 ; cited in Edinb. Med. and Surg. Journal for July, 1834. 6 Memoranda der Speciellen Physiologie des Menschen, S. 265, Weimar, 1853. 88 SENSIBILITY. is dilated to admit more of the luminous rays: on the contrary, if the light be powerful, it contracts. We see this very manifestly on open- ing the eyes, after they have been for some time closed, and bringing a candle suddenly near them. It is one of the means frequently em- ployed in cerebral disease to judge of the degree of insensibility. We shall presently inquire into the effect of contraction or dilata- tion of #the pupil on distinct vision; and show, that they are actions for accommodating the eye to vision at different distances. We may conclude, then, that the iris is one of the most important parts of the visual apparatus; that its functions are multiple:—that it is partly the cause of the achromatism of the organ, by preventing the rays of greatest divergence from falling near the marginal parts of the crystalline;—that it corrects the aberration of sphericity; regu- lates the quantity of light admitted through the pupil, and accommo- dates the eye, to a certain extent, to vision at different distances. An enumeration of the multiform sentiments regarding the func- tions of the ciliary processes will show how little we know, that is pre- cise, on this matter also. They have often been considered contractile; some believing them connected with the motions of the iris, others to vary the distance of the crystalline from the retina. Jacobson1 makes them dilate the apertures, which he conceives to exist in the canal godronne, so as to cause the admission of a portion of the aqueous humour into the canal; and thus to change the situation of the crys- talline. Others believe, that they secrete the pigmentum nigrum; and others—the aqueous humour. But the processes are wanting in ani- mals, in which the humours, notwithstanding, exist; and in our igno- rance of their precise function, it has been considered that there is no opinion, perhaps, more probable than that of Haller;2 that thef are destined to assist mechanically in the constitution of the eye; and have no farther use. The function of the retina remains to be considered. It is the part that receives the impression from the luminous rays, which impression is conveyed by the optic nerve to the brain. It was, at one time, universally believed to be the most delicately sensible membrane of the frame. It has been shown by the experiments of M. Magendie,3 that the sensibility of both it and the optic nerve is almost entirely special, and limited to the appreciation of light;—that the general sen- sibility is exclusively possessed by the fifth encephalic pair; and that the nerve of special sensibility is incapable of executing its functions, unless that of general sensibility is in a state of integritv. That dis- tinguished physiologist found, when a couching needle was passed into the eye at its posterior part, that the retina might be punctured and lacerated without the animal exhibiting evidences of pain. The same result attended his experiments on the optic nerves. These nerves, both anterior and posterior to their decussation, as well as the thalami nervorum opticorum, the superficial layer of the tubercula quadrigemina, and the three pairs of motor nerves of the eye gave no signs of general sensibility. On the other hand, the general sensi- 1 Magendie, Precis, edit, cit., i. 78. t Element. Physiol, xvi 4 90 3 Op. cit., i. 83. ' *» AK>- VISION—ACTION OF THE RETINA. 89 bility of the conjunctiva is well known. It is such, that the smallest particle of even the softest substance excites intense irritation. This general sensibility M. Magendie1 found to be totally annihilated by the division of the fifth pair of nerves within the cranium; after which, hard-pointed bodies and even liquid ammonia made no painful impres- sion on the conjunctiva. Nictation was arrested; and the eye remained dry and fixed like an artificial eye behind the paralysed eyelids. The sight, in this case also, was almost wholly lost; but by making the eye pass rapidly from obscurity into the vivid light of the sun, the eyelids approximated; and, consequently, slight sensibility to light remained; but it was slight. In,this sense, then, as in the senses of hearing and smell, we have the distinction between a special nerve of sense, and one of general sensibility: without the latter, the former is incapable of executing its elevated functions. The expansion of the retina occupies at least two-thirds of the cir- cumference of the eyeball. It is of obvious importance, that it should have as much space as possible; and, in certain animals, in which the sense is very acute, the membrane is plaited so as to have a much larger surface than the interior of the eyeball; and thus to allow the same luminous ray to impinge upon more than one point of the mem- brane. This is seen in the eyes of the eagle and vulture, and in noc- turnal animals. The inconceivable acuteness of the sense of sight in birds of prey has been already referred to under the sense of smell. It was then stated, that the strange facts regarding the condor, vulture, turkey-buzzard, &c, which meet in numbers in the forest, when an animal is killed, ought rather, perhaps, to be referred to acuteness of the sense of sight than of smell. Sir Everard Home2 affords an addi- tional illustration of this subject. In the year 1778, Mr. Baber, and several other gentlemen were on a hunting party in the island of Cas- simbusar, in Bengal, about fifteen miles north of the city of Marshe- dabad: they killed a wild hog of uncommon size, and left it on the ground near the tent. An hour after, walking near the spot where it lay, the sky being perfectly clear, a dark spot in the air, at a great distance, attracted their attention; it appeared to increase in size, and move directly towards them; as it advanced it proved to be a vulture flying in a direct line to the dead hog. In an hour, seventy others came in all directions, which induced Mr. Baber to remark,—" this cannot be smell!" How inconceivably sensible to its special irritant must this mem- brane be in the human eye, when we consider that every part of an extensive landscape is depicted upon its minute surface; not only in its proper situation, but with all its varied tints; and how impractica- ble for us to comprehend, how the infinitely wider range of country can be so vividly depicted on the diminutive eye of the vulture, as to enable it to see its prey from such remote distances. If pressure be made on the eyeball, behind the cornea, so as to affect the retina, concentric luminous circles are seen, opposite to the part on 1 Op. cit., i. 494. 2 Lectures on Comparative Anatomy, Lond., 1814-1828. 90 SENSIBILITY. which the pressure is applied; and, if the pressure be continued for twenty or thirty seconds, a broad undefined light, which increases in intensity every moment, rises immediately before the eye. If the eye- lids be open, and light be present—on the repetition of the last expe- riment, a dense cloud arises, instead of the broad undefined light; and the eye becomes, in a few seconds, perfectly blind; but in the course of three or four seconds after the finger is removed, the cloud appears to roll away from before the eye. From this, it seems, that sensations of light may be produced by mechanical pressure made on the retina; in other words, the retina becomes phosphorescent by pressure. ,r The same thing is observed if a sudden blow be given on the eye, or if we place a piece of zinc under the upper lip, and a piece of copper above the eye. A flash of light is seen; produced, doubtless, by the galvanic fluid impressing directly, or indirectly, the optic nerve. The same thing occurs in the act of sneezing, and in forcing air violently through the nostrils. On repeating the experiment of pressing the eyeball, Sir David Brewster1 observed, that when a gentle pressure is first ap- plied, so as to compress slightly the fine pulpy substance of the retina, a circular spot of colourless light is produced, though the eye be in total darkness, and has not been exposed to light for many hours; but if light be now admitted to the eye, the compressed part of the retina is found to be more sensible to the light than any other part; and, consequently, it appears more luminous. If the pressure be increased beyond the point mentioned above, the circular spot of light gradually becomes darker, and, at length, black, and is surrounded with a bright ring of light. By augmenting the pressure still more, a luminous spot appears in the middle of the central dark one, and another luminous spot diametrically opposite, and beneath the point of pressure. " Con- sidering the eye," says Sir David, "as an elastic sphere, filled with in- compressible fluids, it is obvious, that a ring of fluids will rise round the point depressed by the finger; and that the eyeball will protrude all round the point of pressure; and consequently the retina, at the protruded part, will be compressed by the outward pressure of the con- tained fluid, while the retina on each side,—that is, under the point of pressure, and beyond the protruded part,—will be drawn towards the protruded part or be dilated. Hence the part under the finger, which was originally compressed, is now dilated, the adjacent parts are com- pressed, and the more remote parts, immediately without this, dilated also." " Now," continues Sir David, " we have observed, that when the eye is, under these circumstances, exposed to light, there is a bright luminous circle shading off externally and internally into total dark- ness. We are led therefore to the important conclusions, that when the retina is compressed in total darkness it gives out light; that when it is compressed, when exposed to light, its sensibility to light is in- creased ; and that when it is dilated under exposure to light, it becomes absolutely blind or insensible to all luminous impressions." Having traced the mode in which the general physiology of vision is effected, and the part performed by each of the constituents of the eye proper, we shall briefly consider the functions of the rest of the 1 Letters on Natural Magic, Amer. edit., p. 27, New York, 1832. VISION—ACTION OF THE ACCESSORY ORGANS. 91 visual apparatus, the anatomical sketch of which has been given under the head of accessory organs; and afterwards inquire into the various interesting and important phenomena exhibited by this sense. These organs perform but a secondary part in vision. The orbit shelters the eye, and protects it from external violence. The eyebrows have a similar effect; and, in addition to this, the hair, with which they are furnished, by virtue of its oblique direction towards the temple, and by the seba- ceous secretion that.covers it, prevents the perspiration from flowing into the eye, and directs it towards the temple or root of the nose. By contracting the eyebrows, they can be thrown forwards and downwards in wrinkles; and can thus protect the eye from too strong a light, especially when coming from above. The eyelids cover the eye during sleep, and preserve it from the con- tact of extraneous bodies. During the waking state, this protection is afforded by the instantaneous occlusion of the eyelids, on the anticipa- tion of danger to the ball. The incessant nictation likewise spreads the lachrymal secretion over the surface of the conjunctiva, and cleanses it; whilst the movement, at the same time, probably excites the gland to augmented secretion. The chief part of the movement of nictation is performed by the upper eyelid; the difference in the action of the eyelids being estimated, by some physiologists, as four to one. Under ordinary circumstances, according to M. Adelon,1 it is the levator pal- pebrse superioris, which, by its contraction or relaxation, opens or closes the eye; the orbicularis palpebrarum not acting. If the levator be contracted, the eyelid is raised and folded between the eye and orbit, and the eye is open; if, on the other hand, the levator be relaxed, or spread passively over the surface of the organ, the eye is closed. In this view, the orbicularis muscle is not contracted, except in extraordi- nary cases, and under the influence of volition; whilst the closure of the eye during sleep is dependent upon simple relaxation of the leva- tor. The views of M. Broussais2 on this subject are more satisfactory. He considers, that the open state of the eye, in the waking condition, requires no effort; because the two muscles of the eyelids are so ar- ranged, that the action of the levator is much more powerful than that of the orbicularis; and he adduces, in proof of this, that the eyelids, at the time of death, are half open. On the other hand, the closure of the eye in sleep he conceives to be owing to the contraction of the orbicularis muscle, which acts whilst the others rest. If the opening of the eye were wholly dependent upon the action of the levator pal- pebras superioris, its relaxation during insensibility and death ought to be sufficient to close the eye completely; and the orbicularis palpe- brarum would be comparatively devoid of function; being only neces- sary for the closure of the organ under the influence of volition. It has been found by experiments instituted by Sir Charles Bell,3 and by M. Magendie,4 that nictation is effected under the influence chiefly of the portio dura of the seventh pair or facial nerve,—one of the respiratory nerves of Sir Charles Bell's system—the respiratory of the face. When this nerve is cut, nictation is completely arrested; and 1 Physiologie de l'Homme, 2de edit., i. 419, Paris, 1829. 2 Op. citat., p. 188. 3 The Nervous System of the Human Body, Amer. edit., p. 48, Washington, 1833. 4 Precis Elenientaire, i. 309. 92 SENSIBILITY. when the nerve of the fifth pair, also distributed to these parts, is divided, it ceases likewise, but less thoroughly; a very vivid light exciting it, but only at considerable intervals, and imperfectly. We see here something very analogous to the partition of the nerves of the senses into those possessing general, and special sensibility. Like the latter functionaries, the nerve of the seventh pair appears to be specially concerned in nictation, and not to be capable of executing its office, unless the fifth pair—the nerve of general sensibility—be in a state of integrity. The explanation of Dr. Marshall Hall is different. It has been before remarked, that if the functions of the brain be suspended or destroyed, the true spinal system being uninjured, the orbicularis palpebrarum still contracts so as to close the eyelids, when the tarsus is touched with any solid body. In this case, neither sensation nor volition can be concerned. It is a reflex action; the excitor nerves being probably branches of the fifth, and the motor, branches of the seventh pair. Hence, when the will ceases to act, as in sleep, or in apoplexy, the lids close over the eye to protect it. In the waking state, the levator palpebrae, under the influence of the will, acts as an antagonist to the orbicularis and keeps the eye open ; but there is an almost irresistible tendency to close the eye; and, as in the case of respiration, the muscular contraction can only be restrained to a cer- tain degree: it takes place, whenever the condition of the conjunctiva is such as to occasion an irrfpression to be conveyed along the excitor nerve which demands a reflex movement to modify it; for example, when particles of dust collect upon it; or the surface becomes dry.1 The eyelids, by their approximation, can regulate the quantity of light that enters the pupil, when it is injuriously powerful; when feeble, they are widely separated, to allow as much light as possible to penetrate the organ. By their agency, again, the most diverging rays from an object can be prevented from falling upon the cornea; and the vision of the myopic or short-sighted can be assisted. It is a means of which they often avail themselves. The cilia or eyelashes, it is pro- bable, are of similar advantage as regards the admission of light into the eye, and, probably, have some part in preventing extraneous bodies, borne about in the air, from reaching the sensible conjunctiva. The muscles of the eyeball have acquired the chief portion of their interest in recent times, and largely through the investigations of the eminent physiologist—of whose labours we have so frequently had occasion to speak—Sir Charles Bell.2 The arrangement of the four straight muscles, and especially their names, sufficiently indicate the direction in which they are capable of moving the organ, when acting singly. If any two of them contract together, the eyeball will, o°f course, be moved in the direction of the diagonal between the two forces; and if each muscle contracts rapidly after the other, the organ will execute a movement of circumduction. The oblique muscles are in some respects antagonists to each other, and roll the eye in opposite directions; the superior oblique directing the pupil downwards and inwards; the inferior upwards and inwards. But as the different 1 Carpenter, Human Physiology, p. 154, London, 1842. 2 Op. citat., p. 102, and Anatomy and Physiology, 5th Amer. edit., ii. 213, New York VISION—ACTION OF THE MUSCLES OF THE EYEBALL. 93 straight muscles are capable of carrying the eye in these directions, were we to regard the two sets of muscles as possessing analogous functions, the oblique would appear to be superfluous. This, along with other reasons, attracted the attention of Sir Charles Bell to the subject; and the result of his experiments and reflections was;—that the straight muscles are concerned in the motions of the eye excited by volition ; and that the oblique muscles are the organs of its invol- untary motions. In this manner, he accounts for several phenomena, connected with the play of the organs in health and disease. Whilst the power of volition can be exerted over the recti muscles, the eye is moved about, in the waking state, by their agency; but, as soon as volition fails from any cause, the straight muscles cease to act, and the eye is turned up under the upper eyelid. Hence this happens at the approach of, and during sleep; and whenever insensibility occurs from any cause, as in faintness, or on the approach of dissolution ; and the turning up of the eyeball, which we have been accustomed to regard as the expression of agony, is but the indication of a state of incipient or total insensibility. Whenever, too, the eyelids are closed, the eye- ball is moved, so that the cornea is raised under the upper eyelid. If one eye be fixed upon an object, and the other be closed with the finger so placed as to feel the convexity of the cornea through the upper eyelid, and the open eye be shut, the cornea of the other eye will be found to be elevated. This change takes place during the most rapid winking motions of the eyelids; and is obviously inservient to the protection of the eye; to the clearing of the eyeball of everything that could obscure vision, and perhaps, as Sir Charles Bell presumes, to procure the discharge from the ducts of the lachrymal gland. During sleep, when the closure of the eye is prolonged, the transparent cornea is, by this action, turned up under the upper eyelid, where it is securely lodged and kept moist by the secretions of the lachrymal gland, fol- licles, and conjunctiva. The different distributions of the motor nerves of the eye have been described in the anatomical sketch. It was there stated, that the supe- rior oblique muscle receives one whole pair of nerves,—the fourth. This nerve, then, it seemed to Sir Charles Bell, must be concerned in the functions we have described; and, as the various involuntary motions of the eyeball are intimately concerned in expression, as in bodily pain, and in mental agony,—in which the action of the direct muscles seems, for a time, to be suspended,—he was led to consider the fourth as a nerve of expression,—a respiratory nerve; and, hence, intimately connected with the facial of the seventh pair, which, as has been already remarked, is the great nervous agent in the twinkling of the eyelids. Anatomical examination confirmed this view,—the roots of the nerve being found to arise from the same co- lumn as other respiratory nerves. The coincidence of this twinkling, and of the motion of the eyeball upwards, was, therefore, easily under- stood. There is a difficulty, however, here, which has doubtless already sug- gested itself to the reader. The fourth pair is distributed to the supe- rior oblique only; the lesser oblique receives none of its ramifications. They cannot, therefore, be identically situate in this respect. Yet 94 SENSIBILITY. they are both considered by Sir Charles Bell as involuntary muscles. The action, indeed, of the lesser oblique would appear to be even more important than that of the greater oblique, as the function of the former, when acting singly, is to carry the eye upwards and inwards; and, when the action of its antagonist is abolished, this is more clearly manifested. Sir Charles found, that the effect of dividing the supe- rior oblique was to cause the eye to roll more forcibly upwards;—in other words, it was given up, uncontrolled, to the action of the anta- gonist muscle. This difficulty, although it is not openly stated by Sir Charles, must have impressed him; for, after having referred to the effect of the division of the superior oblique, he is constrained to suggest an influence to the fourth pair, which would, we think, be anomalous;—that it may, on certain occasions, cause a relaxation of the muscle to which it goes, and, in such case, the eyeball must be rolled upwards. In addition to this, too, as Mr. Mayo1 has observed, the distribution of the muscular nerves of the eye is not such as to allow of our opposing the straight muscles to the oblique; and one cogent reason is, that the third pair supplies part of each class. We have still, therefore, much to learn regarding this subject, into which so much interest, and, at the same time, so much uncertainty has been infused. In some experiments on the fresh subject, made by the author with Professor Pancoast, who carefully separated the differ- ent muscles, with the view of discovering their precise action, it was clearly apparent, that the oblique muscles act in the manner above mentioned; the superior oblique directing the eye slightly inwards and downwards; and the inferior rolling it upwards and inwards, when they acted singly; when the two were brought into action, simultane- ously, they appeared to antagonize each other as rotators, but pro- jected the eye forward. It would seem, indeed, that an important use of these muscles is to keep the eye prominent during the action of the straight muscles. These results harmonize greatly with the deductions from experi- ments on living animals by Mr. Bransby Cooper.2 He divided the superior and inferior oblique muscles of the eyes of several living rabbits: and inferred, that the oblique muscles, when acting together, suspend the eyeball in a central position in the orbitar cavity; moderate the retracting influence of the four straight muscles; and, when acting in succession, without being restricted by the influence of the straight muscles, they roll the eye on its own axis, drawing the globe forward and at the same time tending, in a great degree, to extend the sphere of vision.3 The great use of the tears would seem to be to moisten the conjunc- tiva, and to remove extraneous bodies from its surface,__thus assisting the motions of the eyelids and eyeball. The tears are secreted by the lachrymal gland; and, by means of its excretory ducts, are poured upon the surface of the tunica conjunctiva, at the upper and outer part of the eyeball. Their farther course towards the puncta lacrymalia has 1 Outlines of Human Physiology, 4th edit., p. 299, London, 1837. 2 Guy's Hospital Reports, vol. iii., April and October, 1838.' edit See, on all this subject, Carpenter's Principles of Human Physiology 5th Amer ., p. 913, Philad., 1853. ' VISION—ACTION OF THE MUSCLES OF THE EYEBALL. 95 been the subject of difference of sentiment. Many physiologists have considered that, owing to the form of the tarsal cartilages, a canal exists, when the eyelids are closed, of a triangular shape, formed an- teriorly by the junction of the cartilages, and behind by the ball of the eye. M. Magendie,1 on the other hand, denies the existence of this canal; and asserts that the tarsal cartilages do not touch by a rounded edge, but by an inner plane surface. If we were to grant the existence of this canal, it could only aid us in our explanation of the course of the tears during sleep. In the waking state, they are not ordinarily secreted in such quantity as to require that much should pass to the puncta;—the movements of nictation spreading them over the surface of the eye, whence they are partly absorbed, and the rest, perhaps, evaporated. Under extraordinary circumstances, however, the gland increases its secretion so much, that the tears not only pass freely through the lachrymal ducts into the nose, but flow over the lower eyelid. The epiphora or watery eye, caused by obstruction of these ducts, also proves that a certain quantity of the secretion must always be passing into the puncta. The physical arrangement of the eyelids and tunica conjunctiva is doubtless the cause of their course in this direction. It has been gratuitously supposed by some, that the humour of Meibomius prevents the tears from reaching the outer surface of the lower eyelid, by acting like a layer of oil on the margin of a vessel filled with water. A similar function has been assigned to the secre- tion of the caruncula lacrymalis. Both these fluids, however, are probably inservient to other ends. They are readily miscible with water; become consequently dissolved in the tears, and, with the assist- ance of the fluid secreted by the tunica conjunctiva, aid the movements of the eyelids over the ball of the eye, and keep the tarsal margins and their appendages in the condition requisite for the due perform- ance of their functions. The action of the puncta themselves in admitting the tears has re- ceived different explanations. M. Adelon2 regards it as organic and vital. We ought, however, in all cases, to have recourse to this mode of-accounting for phenomena as the ultima ratio ; and the present ap- pears to be a case in which it is singularly unnecessary. In many of the results of absorption we are compelled to suppose, that a vital operation must have been concerned in the process. Where, for example, as in the case of the lymphatic vessels, we find the same fluid circulating, whatever may have been the nature of the substances whence it was obtained, the evidence, that a vital action of selection and elaboration has been going on, is irresistible; but there is no such action in the case in question. The tears in the lachrymal ducts and ductus ad nasum are identical with those spread upon the surface of the eye. This is one of the few cases in the human body, which admit of satisfactory explanation on the physical principles of capillary attraction. In vegetables, the whole of the circulation of their juices has been thus accounted for. If we twist together several threads of 1 Precis, &c, edit, cit., i. 52. 2 Physiologie, 2de edit., p. 421, Paris, 1829. 96 SENSIBILITY. yarn; moisten them; and put one extremity of the roll into a vessel of water, allowing the other to hang down on the outside and to dip into an empty vessel placed below it,—we find, that the whole of the fluid in the first vessel is in a short time transferred to the second. If, again, we take a small capillary tube, less than the twentieth part of an inch in diameter, and place it so as to touch the surface of water, we find, that the water rises in it to a height, which is greater, the smaller the bore of the tube. If the diameter of the tube be the fiftieth part of an inch, the water will rise to the height of two inches and a half; if the one hundredth part of an inch, to five inches ; if the two hundredth part of an inch, to ten inches; and so on. Now, the punc- tum lacrymale is, in our view of the subject, the open extremity of a capillary tube, which receives the fluid of the lachrymal gland and con- veys it to the nose,—the punctum being properly directed towards the eyeball by the tensor tarsi muscle of Horner, and the inspiratory movements drawing it down the ductus ad nasum. Lastly:—the tunica conjunctiva is another part of the guardian appa- ratus of the eye. It secretes a fluid, which readily mixes with the tears, and appears to have similar uses. Like mucous membranes in general, it absorbs; and, in this way, a part of the lachrymal secretion is re- moved from its surface. An animal, for the same reason, can be readily poisoned by applying hydrocyanic acid to it. As the conjunctiva lines the eyelids, and is reflected over the globe, it supports the friction, when the eyeball or eyelids are moved; but, being highly polished and always moist, this is insignificant. The extreme sensibility of the outer part of the eye appertains to the tunica conjunctiva, and is dependent on the ophthalmic branch of the fifth pair. When this nerve was divided in a living animal, M. Magendie1 found, that the membrane became entirely insensible to every kind of contact, even of substances that destroyed it chemically. In his experiments on this subject, he arrived at singular results, re- garding the influence of the fifth nerve on the nutrition of the eye. When the trunk of the nerve was divided within the cranium a little after its passage over the petrous portion of the temporal bone, the cornea was found, about twenty-four hours afterwards, to become troubled; and a large spot to form upon it. In the course of from forty-eight to sixty hours, the part was completely opaque; and the conjunctiva, as well as the iris, in a state of inflammation; a turbid fluid was thrown out into the inner chamber, and false membranes pro- ceeded from the interior surface of the iris. The crystalline and vitreous humours now began to lose their transparency; and, in the course of a few days, were entirely opaque. Eight days after the divi- sion of the nerve, the cornea separated from the sclerotica; and the portions of the humours that remained fluid escaped at the opening The organ diminished in size, and ultimately became a kind of tubercle' filled with a substance of a caseous appearance. M. Magendie properly concludes from these experiments, that the nutrition of the eye is under the influence of the fifth pair; and he conceives, that the opacity of the cornea was directly owing to the section of this nerve, and not to 1 Precis Elementaire, ii. 494. VISION — EXPERIMENT OF MARIOTTE. 97 a cessation of the lachrymal secretion, or to the prolonged contact of air, caused by the paralysis of the eyelids; inasmuch as when only the branches of the nerve proceeding to the eyelids were divided, or when the lachrymal gland was taken away, the opacity did not supervene. 5. PHENOMENA OF VISION. It has been more than once remarked, that the retina—the expan- sion of the optic nerve—is the part of the eye which receives the impressions of luminous rays, whence they are conveyed by that nerve to the brain. Yet this has been contested. The Abbe Mariotte1 discovered the singular fact, that when a ray of light falls, as he conceived, upon the centre of the optic nerve it excites no sensation. " Having often observed," he remarks, " on dis- sections of men as well as of brutes, that the optic nerve does never answer just to the middle of the bottom of the eye; that is, to the place where the picture of the object we look directly upon is made; and that in man it is somewhat higher, and on the side towards the nose; to make therefore the rays of an object to fall upon the optic nerve of my eye, and to find the consequence thereof, I made this ex- periment. I fastened on an obscure wall, about the height of my eye, a small round paper, to serve me for a fixed point of vision. I fas- tened such another on the side thereof towards my right hand, at the distance of about two feet, but somewhat lower than the first, to the end that I might strike the optic nerve of my right eye, while I kept my left shut. Then I placed myself over against the first paper, and drew back by little and little, keeping my right eye fixed and very steady on the same, and being about ten feet distant, the second paper totally disappeared." The experiment of Mariotte can be readily repeated on the marginal representations of the fleur-de- lis and arrow. If we close the Fig* 297. left eye, and direct the axis of f ^ the right eye Steadily towards Experiment of Mariotte. the arrow, when the page is held at the distance of about ten inches from the eye, the fleur-de-lis vanishes. The distance of the object which disappears from the eye must be about five times as great as its distance from the other object. In this case the fleur-de-lis and arrow are two inches asunder. It is obvious, from what has been said, regarding the axis of the orbits, and the part of the eyeball at which the optic nerve enters—that rays of light from an object can never fall, at the same time, upon the in- sensible point of each eye. The defect in vision is, consequently, never experienced except in such experiments as those performed by Mariotte. In one of these he succeeded in directing the rays to the insensible point of both eyes at once, lie put two round papers at the height of the eye, and at the distance of three feet from each other. By then placing himself opposite them, at the distance of twelve or thirteen feet, and holding his thumb before his eyes, at the distance of 1 Philos. Transact., iii. G68, and Memoir, de l'Academie Royale des Sciences, torn. i. pp. t>8 and 102. VOL. II.—7 98 SENSIBILITY. about eight inches, so that it concealed from the right eye the paper on the left hand, and from the left eye the paper on the right, he looked at his thumb steadily with both eyes, and both the papers were lost sight of. These experiments show, that there is a part of the re- tina or optic nerve, which is, in each eye, insensible to light; and that this point—punctum ccecum—is on the nasal side of the axis. No sooner, however, had Mariotte published an account of his experi- ments, than it was decided that this spot was the basis of the optic nerve; a conclusion was accordingly drawn, that the nerve is inca- pable of distinct vision, and this conclusion has been embraced, with- out examination, in many of the books on optics to the present time. Although probable, however, it is by no means certain that the light, in these cases, falls upon the base of the nerve. The direction in which the ray proceeds is such that it is reasonable to suppose it does impinge there: the suggestion of M. Tillaye,1 that it falls upon the yellow spot of Sommering, can only be explained by presuming him to have been in utter ignorance of the situation of the yellow spot, which, we have seen, is on the outer side of the nerve. But, granting that the light falls at the base of the optic nerve, it by no means demonstrates, that the nerve is incapable of receiving the impression. It has been already shown, that the central artery of the retina penetrates the eye through the very middle of the nerve; and that through the same opening, the central vein leaves the organ. It is probable, therefore, that, in these experiments, the ray falls upon the bloodvessels, and not upon the medullary matter of the nerve; and if so, we could not expect that there should be sensation. That the insensible spot is of small magnitude is proved by the fact, that if a candle be substituted for the round paper or wafer, the candle does not disappear, but becomes a cloudy mass of light. Daniel Bernouilli2 —it is true—considered the part of the nerve insensible to distinct impressions to occupy about the seventh part of the diameter of the eye, or about the eighth of an inch; but there must have been some error in his calculations, for the optic nerve itself can rarely equal this proportion. The estimate of Le Cat,3 who was himself a believer in the views of Mariotte, that its size is about one-third, or one-fourth of a line, is probably still wider from the truth in the opposite direction. Simple experiment, with two wafers placed upon a door at the height of the eye, shows clearly, that both the horizontal and vertical dia- meters of the spot must be larger than this.4 The fact, observed by Mariotte, was not suffered to remain in re- pose. A new hypothesis of vision was framed upon it; and, as he considered it demonstrated, that the optic nerve was insensible to light, he drew the inference, that the retina is so likewise; and as vision was effected in every part of the interior of the eye, except at the base of the optic nerve, where the choroid is alone absent, he inferred that the choroid must be the true seat of vision. The controversy, at one time 1 Adelon, Physiologie, 2de edit., i. 448, Paris, 1829. 2 Haller, Element. Physiolog., xvi. 4, 4. » Traite des Sens, p. 166, Paris, 1767; or English translation, Lond., 1750 < Medical and Physiological Problems, by William Griffin, M. D., and Daniel Griffin M. D., p. 113, Lond., 1845. ei urimn, SEAT OF VISION. 99 maintained on this subject, has died away, and it is not our intention to disturb its ashes, farther than to remark, that De La Hire,1 who engaged in it, entertained the opinion, that the retina receives the im- pression of the light in a secondary way, and through the choroid coat as an intermediate organ; and that by the light striking the choroid, the membrane is agitated, and the agitation communicated from it to the retina. The views of De La Hire are embraced by Sir David Brewster,2 as well as by numerous other philosophers. The opinions of Mariotte have now few supporters. The remarks already made regarding the optic nerve; the effect of disease of the retina, of the nerve itself, and of its roots, compel us to regard its expansion as the seat of vision; and if we were even to admit, with Mariotte, that the insensible portion is really a part of the medullary matter of the nerve, and not a bloodvessel existing there, we could still satisfactorily account for the phenomenon by the anomalous cir- cumstances in which the nervous part of the organ is there placed. The choroid coat, of great importance in the function, as well as the pigmentum nigrum, is absent; and hence we ought not to be surprised, that the function is imperfectly executed:—we say imperfectly, for the experiment with the candles exhibits, that the part is not really insen- sible to light, or is so in a very small portion of its surface only. It may seem at first sight, that the fact of this defect existing only in the centre of the optic nerve, or at the porus opticus as it has been termed, where the central artery of the retina enters, and the corresponding vein leaves the organ, militates against the idea of its being caused by the rays impinging upon these vessels; as, if so, we ought to have similar defects in every part of the retina, where the ramifications of these vessels exist. Circumstances are not here, however, identical. When the ray falls upon the porus opticus, it strikes the vessels in the direction of their length; but, in the other cases, it falls transversely upon them, pierces them, and impresses the retina beneath; so that, under ordinary circumstances, little or no difference is perceived be- tween the parts of the retina over which the vessels creep, and others. We can, however, by an experiment of Purkinje, described by J. G. Steinbuch,3 exhibit, that under particular circumstances such difference really does exist, and renders the bloodvessels of the organ perceptible to its own vision. If, without closing the eyelids, the left eye be covered with the hand, or some other body, and a candle or lamp be held in the right hand, within two or three inches of the right eye, but rather below it, (keeping the eye directed straight forward,) on moving the candle slowly from right to left, (or if the candle be held on the right side of the eye, it may be moved up and down,) a spectrum appears, after a short time, in which the bloodvessels of the retina, with their various ramifications, are distinctly seen projected, as it were, on a plane without the eye, and greatly magnified. They seem to proceed from the optic nerve, and to consist of two upper and two lower branches, which ramify towards the field of vision, where a dark 1 Mem. de l'Academie, torn. ix. 2 Treatise on Optics, Amer. edit., by A. D. Bache, p. 243, Philad., 1833. 3 Beitrag zur Physiologie der Sinne, Niirnberg, 1811; and J. Miiller, Elements of Physiology, by Baly, ii. 1163, Lond., 1839. 100 SENSIBILITY. Fig. 298. spot is seen, corresponding to the foramen centrale. The origin of the vessels is a dark oval spot, with an areola. This phenomenon must be accounted for by the parts of the retina, covered by the bloodvessels, not being equally fatigued with those that are exposed. It is by no means uncommon for appearances of cobwebs, small tubes with lateral pores, &c, to present themselves before the eyes, without changing their position when the eyes are fixed upon an object. These appearances are not owing to any modification in the humours, but are apparently dependent upon the physical condition of the retina. Some years ago, a tube of the kind mentioned, but apparently termi- nating in an open mouth, was the occasion of some uneasiness to the author. This is now no longer seen, but numerous opacities, some- what resembling plexuses of vessels or nerves, are still apparent. All these appearances are usually called collectively u muscae volitantes." They have been described by Mr. T. W. Jones1 under three forms:— first, as a convoluted string of beads, or a convoluted transparent tube, containing in its interior a row of beads smaller than its diameter, except here and there where one larger than the rest is seen occupying its whole diameter,—the end of the string or tube sometimes presenting a dark knobbed extremity, as if formed by an aggregation of the beads composing the string, or contained within the tube (Fig. 298, a); secondly, insulated beads, some of which— and these are more frequent, have a well- defined outline b;—others, and these are rarer, have a distinct outline c; and thirdly, a parcel of flexuous round watery-looking or spun-glass-like filaments with dark con- tours, often divided inferiorly into trun- cated branches, d. The muscae, which change their position, would appear to be seated in the humours of the eye; and it has been supposed in the vitreous more especially: whence the term ento-hyaloid muscae given to them. It has been remarked, that the rays, proceeding from the upper part of an object, impinge upon the lower portion of the retina; and those from the lower part on the upper; hence the image of the object is reversed, as in Fig. 295. It has, accordingly, been asked;—how it is, that we see the object in its proper position, as its image is inverted on the retina? Buffon,2 Le Cat,3 and others believed, that, originally we do see them so inverted; but that the sense of touch apprises us of the error, and enables us to correct it at so earlv a period, and so effect- ually, that we are afterwards not aware of the process. This cannot apply, however, to the lower animals; and, accordingly, the knot has 1 The Principles and Practice of Ophthalmic Medicine and Surgery Amer ArHt t, 323, Philad., 1847. S *' eaitl' P- 2 Memoires de l'Academie, 1743, p. 231. 3 r*„ -A , ' x Up. citat. Muscae Volitantes. CAUSE OF ERECT VISION. 101 been cut by the supposition—and there is much to favour it—that in them it is innate or intuitive.1 Berkeley,2 again, asserted, that the posi- tion of objects is always judged of, by comparing them with our own; and that, as we see ourselves inverted,—and this view is embraced by Miiller, Volkmann,3 and numerous others,—external bodies are in the same relation to us as if they were erect. It is not necessary to reply at length to these views. Cases enough have occurred of the blind from birth having been restored to sight to show, that no such inver- sion, as that described by Buffbn, takes place; and the boy, who stoops down, and looks at objects between his legs, although he may be, at first, a little confused, from the usual position of the images on the retina being reversed, soon sees as well in that way as in any other. The great error with all these speculatists has been, that they have imagined a true picture to be formed on the retina, which is regarded by the mind, and therefore seen inverted. It need hardly be said, that there is no interior eye to take cognizance of this image; but that the mind accurately refers the impression, made upon the retina, to the object producing it; and if the lower part of the retina be impressed by a ray from the upper part of an object, this impression is conveyed by the retina to the brain as it receives it, and no error can be in- dulged. Professor Alison4 offers an explanation, first suggested to him by Mr. Dick, veterinary surgeon, which turns on the alleged fact, that the course of the optic nerves and tractus optici is such, that im- pressions on the upper part of the retina are, in fact, impressions on the lower part of the optic lobes,—that impressions on the outer part of the former are on the inner part of the latter,—and conversely. Mr. Bain5 is of opinion, that to make the seeing of objects erect bjr means of an inverted image on the retina a phenomenon demanding explanation is to misapprehend entirely the process of visual percep- tion. "An object seems to us to be up or down according as we raise or lower the pupil of the eye in order to see it. The very notion of up and down is derived from our feelings of movement, and not at all from the optical image formed on the back of the eye. Wherever this image was formed, and however it lay, we should consider that to be the top of the object, which we had to raise our eyes or our body to reach." When a cone of light proceeds from a radiant point, as from B, Fig. 295, the whole of the rays,—whatever may be their relative obliquity,— are, as has been seen, converged to a focus upon the retina at b, yet the point B is seen only in one direction, in that of the central ray or axis of the cone B b. If we look over the top of a card at the point B, till the edge of the card is just about to hide it; or if, in other words, we obstruct all the rays that pass through the pupil, excepting the upper- most, the point is still seen in the same direction as when it was viewed 1 Carpenter, Human Physiology, p. 266, Lond., 1842. 2 Essay on Vision, 2d edit., p. 60, Dublin, 1709. 3 Wagner's Handworterbuch der Physiologie, 14te Lieferung, S. 342, Braunschweig, 1846. 4 On Single and Correct Vision, by means of Double and Inverted Images on the Retinae, in Transact, of the Royal Society of Edinburgh, vol. xiii., Edinb., 1836. * The Senses and the Intellect, by Alexander Bain, A. M., p. 233, Lond., 1855. 102 SENSIBILITY. n by the whole cone proceeding from B. If we look, again, beneath the card, in a similar manner, so as to see the object by the lowest ray of the cone, the radiant point will be equally seen in the same direction. Hence, says Sir David Brewster,1 it is manifest, that the line of visible direction does not depend on the direction of the ray, but is always per- pendicular to the retina; and as the surface of the retina is a portion of a sphere, those perpendiculars must all pass through one point, "which may be called the centre of visible direction; because every point of a visible object will be seen in the direction of a line drawn from this centre to the visible point." The point o, Fig. 295, is, in Sir David's view, the centre of visible direction. Where a luminous cone proceeds in the direction of the axis of the eye, the centre of visible direction will fall in that line, and a perpendicular, drawn from the point b, where the rays of the cone meet at a focus on the retina, will pass through this centre of visible direction o, and the same thing, he conceives, will apply to every other pencil of rays. Thus, the rays from D and E, which fall upon the cornea at t, will be refracted so as to impinge upon the retina at s and r respectively; and D and E will be seen in the direction of lines drawn from these points to the centre of visible direction, o. This "law of visible direction" removes at once, Sir David Brewster thinks, every difficulty that besets the subject of the cause of erect vision from an inverted image on the retina. The lines of visible direction necessarily cross each other at the centre of visible direction, so that those from the lower part of the image go to the upper part of the object; and those from the upper part of the image to the lower part of the object. The views of Sir David are embraced by Mr. Mayo,2 who considers them confirmed by the fact—to which reference has already been made —that any pressure made upon the retina through the eyeball causes a spectrum to be seen in a direction opposite to the point compressed; as well as by the following experiments of Scheiner, by whom this law of visual direction was first shown. If the head of a pin, strongly illuminated, be viewed with one eye at a distance of four inches, that is, within the common limit of distinct vision, the object is seen large and imperfectly defined,—the outermost cones of rays, which enter the pupil from each point, being too divergent to be collected to a focus on the retina. If a card pierced with a pinhole be now interposed be- tween the eye and the object, the latter may be seen distinctly defined through the pinhole by means of rays that have entered the pupil nearly parallel, with a slightly divergent tendency. But the object may be seen by rays passing either through the upper or lower part, the right or left side, or the centre of the pupil. On shifting the card for this purpose, the object appears to move in an opposite direction.— Or, if three pinholes be made, one in the centre, and one at either side, the object appears tripled; and if one of the side holes be closed, the opposite of the three objects disappears: if, for example, the left-hand pinhole be closed, the right object disappears.—Again, if the head of a pin, strongly illuminated, be viewed at the distance of eighteen inches 1 Op. citat.,p. 248. 2 Outlines of Human Physiology, 3d edit., p. 277. CAUSE OF ERECT VISION. 103 Fig. 299. its outline is distinct and clear; the rays passing from each point of the object are brought to a point on the retina, but they reach the retina at different angles; and, by interposing a card perforated with a single pinhole, the object may be seen by rays, which enter the upper part, or the lower part, or the centre of the pupil. No change, however, in the visual place of the object occurs in this instance, as the card is being shifted; nor is the image multiplied when seen through several pinholes in the card. The last experiment, says Mr. Mayo, proves, that the angle at which rays of light fall upon the retina does not affect our notion of the place of objects; and, taken with the preceding, establishes as an inductive law, that the retina is so constituted, that, however exerted, each point of it sees in one direction only, that direction being a line vertical to it; or that in every instance of vision, each point of an object is seen in the direction of a line vertical to the point of the retina upon which the rays proceeding from it are collected. It would seem, however, to be a forcible objection to this view of the subject; that all the objects, a, a' and a" on the line ca", Fig. 299, must fall upon exactly the same point of the cornea: and, therefore, upon the same point of the retina; yet, as only one of these lines b a is perpendicu- lar to the point of the retina on which the raj^s are collected, such a perpendicular would obvi- ously refer the position of the object a alone cor- rectly. Moreover, accurate examination would appear to show, that this law of visible direction cannot be optically correct, as the lines of direc- tion cross each other at a point much anterior to the centre of the eyeball. This may be proved by making a diagram of the eye on a large scale, and laying down the course of the rays entering the organ, according to the curvatures, and re- fractive powers of its different parts. In this manner, Volkmann1 found, that the lines of direction cross each other at a point a little behind the crystalline, and that they will thus fall at such different angles on different points of the retina, that no general law can be deduced respecting them. A certain intensity of light is necessary, in order that the retina may be duly impressed, and this varies in different animals; some of which, as we have seen, are capable of exercising the function of vision in the night, and have hence been termed nocturnal. In man, the degree of light necessary for distinct vision varies according to the previous state of the organ. A person, passing from a brilliantly illuminated room into the dark, is, for a time, incapable of seeing any thing; but this effect differs in individuals; some being much more able to see distinctly in obscurity than others. This is owing to the Lines of Visible Direction. 1 Neue Beitrage zur Physiologie des Gesichtsinnes, Leipzig, 1836, and Miiller's Ele- ments of Physiology by Baly, p. 1170, Lond., 1839. See, on this subject, Medical and Physiological Problems, &c, by N. Griffin, M. D., and Daniel Griffin, M. D., p. 97, Lond., 1845. 10-1 SENSIBILITY. retina being more sensible; and, consequently, requiring a less degree of light to impress it. On the other hand, a very powerful light in- jures the retina, and deprives it, for a time, of its function; hence the unpleasant impression produced by the introduction of lights into a room, where the company have been previously sitting in comparative obscurity; or, by looking at the sun. The effect upon the retina, thus induced, is called dazzling. If the light that falls upon the eye is ex- tremely feeble, and we look long and intensely upon any minute object, the retina is fatigued; the sensibility of its central portion be- comes exhausted, or it is painfully agitated; and the objects appear and disappear, according as it has recovered or lost its sensibility; a kind of remission seeming to take place in the reception of the impressions. These affections are considered by Sir David Brewster1 as the source of many optical deceptions, which have been ascribed to a supernatural origin. "In a dark night, where objects are feebly illuminated, their disappearance and reappearance must seem very extraordinary to a person whose fear or curiosity calls forth all his powers of observation. This defect of the eye must have been often noticed by the sportsman, in attempting to mark, upon the monotonous heaths, the particular spots where moor-game had alighted. Availing himself of the slightest difference of tint in the adjacent heaths, he endeavours to keep his eye steadily upon it as he advances; but, whenever the contrast of illumi- nation is feeble, he almost always loses sight of his mark, or if the retina does take it up a second time, it is only to lose it again." In all the cases, in which the eye has been so long directed to a minute object that the retina has become fatigued, on turning the axis slightly away from the object, the light from it will fall upon a neigh- bouring part of the retina, and the object be again perceived, and in the mean time the part, previously in action, will have recovered from its fatigue. By the fact of the retina becoming fatigued by regarding an object for a long time we explain many interesting phenomena of vision. If the eye be directed, for a time, to a white wafer laid upon a black ground; and afterwards to a sheet of white paper, it will seem to have a black spot upon it, of the same size as the wafer;—the retina having become fatigued by looking at the white wafer. On the other hand, if the eye be turned to a black wafer, placed upon a sheet of white paper; and afterwards to another part of the sheet, a portion of the paper, of the size of the wafer, will seem strongly illuminated;— the ordinary degree of light appearing intense, when compared with the previous deficiency. It is on this, that the whole theory of acci- dental colours, as they are called, rests. When the eye has been for some time regarding a particular colour, the retina becomes insensible to this colour; and if, afterwards, it be turned to a sheet of white paper, the paper will not seem to be white, but will be of the colour that arises from the union of all the rays of the solar spectrum, except the one to which the retina has become insensible. Thus if it be directed for some time to a red wafer, the sheet of paper will seem to be of a bluish-green, in a circular spot of the same dimensions as the wafer. This bluish-green image is called an ocular spectrum, because 1 Op. citat., p. 250, VISION—ACCIDENTAL COLOURS. 105 it is impressed upon the eye, and may be retained for a short time; and the colour bluish-green is said to be the accidental colour of the red. If this experiment be made with wafers of different colours, other accidental colours will be observed, varying with the colour of the wafer employed, as in the following table:— Colour of the Accidental Colour, or Colour of the Wafer. Ocular Spectrum. Red, ....... Bluish-green. Orange, . Blue. Yellow, . Indigo. Green, . Violet, with a little red. Blue, . Orange-red. Indigo, . Orange-yellow. Violet, . Yellow-green. Black, . White. White, . Black. Accidental Colours. If all the colours of the spectrum be ranged in a circle, in the pro- portions they hold in the spectrum itself, as in Fig. 300,—the acci- dental colour of any particular colour will be found directly oppo- Fis* 30°* site. Hence the two have been termed opposite colours. It will follow, from what has been said, that if the primary « colour, or that to which the eye has been first directed, be added Biaci to the accidental colour, the result must be the same impression as that produced by the union of all the rays of the spectrum—of white light. The accidental colour, in other words, is what the primitive colour requires to make it colour- less light. The primitive and accidental colours are, therefore, comple- ments of each other; and hence accidental colours have been called complementary colours. They have likewise been termed harmonic, because the primitive and its accidental colour harmonize with each other in painting. It has been supposed, that the formation of these ocular spectra has frequently given rise to a belief in supernatural appearances,—the retina, in certain diseased states of the nervous sys- tem, being more than usually disposed to retain the impressions, so that the spectrum remains visible for a long time after the cause has been removed. Such appears to be the view of Drs. Ferriar,1 Hib- bert,2 and Alderson,3—the chief writers in modern times, on appari- tions. This subject may be the theme of future discussion. It will be sufficient, at present, to remark, that the great seat and origin of spectral illusions is the brain, and that the retina is no farther con- cerned than it is in dreaming or in the hallucinations of insanity. ' An Essay towards a Theory of Apparitions, Lond., 1813. z Sketches of the Philosophy of Apparitions, Edinb., 1825, 3 An Essay on Apparitions, &c, Lond., 1823. 106 SENSIBILITY. The retina is able to receive visual impressions over its whole sur- face, but not with equal distinctness or accuracy. When we regard an extensive prospect, that part of it alone is seen sharply, which falls upon the central part, or in the direction of the axis of the eye: we always, therefore, in our examination of minute objects, endeavour to cause the rays from them to impress this part of the retina;—the dis- tinctness of the impression diminishing directly as the distance from the central foramen increases. This central point, called the point of distinct vision, is readily discriminated on looking at a printed page. It will be found, that although the whole page is represented on the retina, the letter to which the axis of the eye is directed is alone sharply and distinctly seen; and, accordingly, the axis of the eye is directed in succession to each letter as we read. In making some experiments on indistinctness of vision at a distance from the axis of the eye, Sir David Brewster1 observed a singular peculiarity of oblique vision, namely,— that when we shut one eye and direct the other to any fixed point, such as the head of a pin, and hence see all other objects within the sphere of vision indistinctly, if one of these objects be a strip of white paper, or a pin lying upon a green cloth, after a short time, the strip of paper or the pin will altogether disappear, as if it were entirely removed, the impression of the green cloth upon the surrounding parts of the eye extending itself over the part of the retina, which the image of the pin occupied. In a short time, the vanished image will re-ap- pear, and again vanish. When the object seen obliquely is luminous, as a candle, it never vanishes entirely, unless its light is much weak- ened by being placed at a great distance ; but it swells and contracts, and is encircled with a nebulous halo,—the luminous impressions ex- tending themselves to adjacent parts of the retina not directly influ- enced by the light itself. From these, and other experiments of a similar character, Sir David infers, that oblique or indirect vision is inferior to direct vision, not only in distinctness, but from its inability to preserve a sustained vision of objects. Yet it is a singular fact, that indirect has a superiority over direct vision in the case of minute objects, such as small stars, which cannot, indeed, be seen by the latter. A mode frequently adopted by astronomers for obtaining a view of a star of the last degree of faintness is to direct the eye to another part of the field, and in this way, a faint star, in the neighbourhood of a large one, often becomes very conspicuous, so as to bear a certain illumination, and yet it en- tirely disappears, as if suddenly blotted out, when the eye is turned full upon it; and, in this way, it can be made to appear and disappear as often as the observer pleases. Sir J. F. W. Herschel, and Sir; James South, who describe this method of observation, attempt to account for the phenomenon by supposing, that the lateral portions of the retina, being less fatigued by strong light, and less exhausted by perpetual attention, are probably more sensible to faint impressions than the central ones ; and the suggestion carries with it an ai r of veri- similitude. Sir David Brewster, however,—from the result developed by his experiments, that, "in the case of indirect vision, a luminous 1 Op. citat., p. 248. DISTINCT VISION. 107 object does not vanish, but is seen indistinctly, and produces an en- larged image on the retina, besides that which is produced by the defect of convergency in the pencils,"—concludes somewhat mystically, " that a star, seen indirectly, will affect a large portion of the retina from these two causes, and, losing its sharpness, will be more distinct."' In order that the image of any object may impress the retina, and be perceived by the mind; it must, first of all, occupy a space on the retina sufficiently large for its various parts to be appreciated: in the next place, the image must be distinct or sharp,—in other words, the luminous rays that form it must converge accurately to a focus on the retina; and lastly, the image must be sufficiently illuminated. Each of these conditions varies with the size of the body, and the distance at which it is from the eye; and there are cases, where they are all wanting, and the object is consequently invisible. An object may be so small, that the eye cannot distinguish it, because the image, formed on the retina, is too minute. To remedy this inconvenience, the ob- ject must be brought near to the eye, which increases the divergence of the rays and the size of the image; but if we approach it too close to the eye, the rays are not all brought to a focus on the retina, and the image is indistinct. If, therefore, an object be so small, that, at the visual point, to be presently mentioned, the rays proceeding from it do not form an image of sufficient size on the retina, the object is not seen. To obviate this imperfection of the sense, minute bodies may be viewed through a small hjole in a piece of paper or card, or with the instrument called a microscope. By looking through the small aperture in the paper or card, the object may be brought much nearer to the eye; the rays of greatest divergence are prevented by the small- ness of the, hole from impinging upon the retina; and the rest are con- verged to a focus upon that membrane, so that a sharp and distinct impression is received. The iris is, in this way, useful in effecting distinct vision,—the most divergent rays being, by the contraction of the pupil, prevented from falling upon the crystalline. Any object that does not subtend an angle of the sixtieth of a degree is invisible; but the visual power differs greatly in individuals. Some eyes are much more capable of minute inspection than others; and greater facility is acquired by practice. Professor Ehrenberg, how- ever, found, that in regard to the extreme limits of vision, there is lit- tle difference among persons of ordinarily good sight, whatever may be the focal distance of their eyes. The smallest square magnitude usually visible to the naked eye, either of white particles on a black ground, or of black upon a white ground, is about the ^gth of an inch; but particles that reflect light powerfully, as gold dust, may be discovered with the naked eye in common daylight, when not exceed- ing the yy'ojth of an inch; and, when the substance viewed is in lines instead of particles, it may be seen, if held towards the light, when only ^^th of an inch in diameter. Again, there is a point of approximation to the eye beyond which objects cease to be distinctly seen, in consequence of the rays of light striking so divergently upon the eye, that the focus falls behind the 1 Op. oitat., p. 249. 108 SENSIBILITY. retina. This point, too, varies according to the refractive power of the eye; and is, therefore, different in different individuals. In the myopic or short-sighted, it is much nearer the eye than common; in the presbyopic or long-sighted, more distant. The iris here, again, plays an important part, by its action in shutting off' the most diverg- ing rays. There is also a limit beyond which objects are no longer visible. This is owing to the light from them becoming absorbed before it reaches the retina, or so feeble as not to make the necessary impression. The distance, consequently, at which an object may be seen, will depend upon the sensibility of the retina, and partly on the colour of the ob- ject ; a light colour being visible to a greater distance than a darker. A distant object may also be imperceptible owing to the image, traced on the retina, being too minute to be appreciated; for the size of the image diminishes as the distance of the object increases. The range of distinct vision varies, likewise, with the individual,—and especially with the myopic and presbyopic; and in such case the pupil dilates to admit as much light as possible into the interior of the eye, and to compensate in some measure for the defect. Between the ranges of distant and near vision, a thousand different examples occur. In all cases, however, the ocular cone must be brought to a focus on the retina, otherwise there cannot be perfect vision. It has been already observed, in the proem on light, that the distance, at which the ocular cone arrives at a focus behind the lens, is in propor- tion to the length of the objective cone; or, in other words, that the' focus of a lens varies with the distance at which a radiant point is situate before it: where the point is near the lens the focus will he more remote behind it; and the contrary. If this occurs in £he human eye it must necessarily follow;—either that it is not necessary for an object to be impressed upon the retina;—or that the eye is capable of accommodating itself to distances;—or if it does not occur, it must be admitted, that, owing to the particular constitution of the eye, the impressions are so made on the retina as not to need such adaptation. The whole bent of the foregoing observations on vision would pre- clude the admission of the first of these postulates. The second has been of almost universal reception, and given rise to many ingenious speculations; and the third has been seriously urged of late years only. It would occupy too much space to dwell at length upon the various ingenious discussions, and the many interesting and curious experi- ments, that have resulted from a belief in the power possessed by the eye of accommodating itself to distances. It is a subject, however, which occupies so large a field in the history of physiological opinions, that it cannot be passed over. The chief views, that have been enter- tained, are:—First. The cornea or lens must recede from, or approach the retina, according to the focal distance, precisely as we adapt our telescopes by lengthening or shortening the tube. Secondly. If we suppose the retina to be stationary, the lens must experience a change in its refractive powers, by an alteration of its shape or density; or, Thirdly. In viewing near objects, those rays only must be admitted, which are nearest the axis of the eye, and are consequently least di- verging. ADAPTATION OF THE EYE TO DISTANCES. 109 1. The hypothesis, that the adjustment of the eye is dependent upon an alteration of the antero-posterior diameter of the organ, or on the relative position of the humours and retina, has been strongly supported by many able physiologists. Blumenbach1 was of opinion, and his views seem to have been embraced by Dr. Hosack,2 that the four straight muscles of the eye, by compressing the eyeball, cause a protrusion of the cornea, and thus increase the length of the axis. Dr. Monro secundus3 believed, that the iris, recti muscles, the two oblique, and the orbicularis palpebrarum participate in the accommodation; and Hamberger, Briggs,4 and others, that the oblique muscles, being thrown in opposite directions around it, may have the effect of elon- gating the axis of the eye. Kepler5 thought, that the ciliary processes draw the crystalline forward, and increase its distance from the retina. Des Cartes6 imagined the same contraction and elongation to be effected by muscularity of the crystalline, of which he supposed the ciliary processes to be the tendons;—Porterfield,7 that the corpus cili- are is contractile, and capable of producing the same effect;—Jacob- son,8 that the aqueous humour, by entering the canal of Petit through the apertures in it, distends the canal, and pushes the crystalline for- ward;—Sir Everard Home,9 that the muscular fibres, which he has described as existing between the ciliary processes, move the lens nearer to the retina, and that the lens is brought forward by other means, (which he leaves to conjecture,) when the distance of the object is such as to require it;—Dr. Knox,10 that the annulus albus, or the part which unites the choroid and sclerotic coats, is muscular, and the chief agent in this adjustment;—Professor Mile,11 of Warsaw, that the contraction of the iris changes the curvature of the cornea; whilst Sir David Brewster12 thinks it " almost certain, that the lens is removed from the retina by the contraction of the pupil." Without examining these and other views in detail, it may be re- marked, that the nicest and most ingenious examination by the late Dr. Young13 could not detect any change in the length of the axis of the eyeball. To determine this, he fixed his eye, and at the same time forced in upon the ball the ring of a key, so as to cause a very accu- rately defined phantom within the field of perfect vision; then looking to bodies at different distances, he expected, if the figure of the eye were modified, that the spot, caused by the pressure, would be altered in shape and dimensions; but no such effect occurred; the power of accommodation was as extensive as ever, and there was no perceptible 1 Instit. Physiolog., § 276, or Elliotson's translation. 8 Philosoph. Transact, for 1794, p. 146. 3 Three Treatises on the Brain, the Eye, the Ear, p. 137, Edinb., 1797. 4 Nova Visionis Theoria, Lond., 1685. 5 Haller, Element. Physiol., xvi. 4, 2. 6 De Homine, p. 45, Lugd. Bat., 1664. 7 A Treatise on the Eye, the Manner and Phenomena of Vision, Edinb., 1759. 8 Magendie, Precis, &c, i. 78. 9 Philosoph. Transact, for 1794, 1795, 1796, and 1797; and Lectures on Comparative Anatomy, iii. 213, Lond., 1823. ,0 Edinb. Philos. Transact., x. 56. " Magendie, Journal de Physiologie, vi. 166; and Elliotson's Human Physiology, p. 571, Lond., 1840. 12 Edinburgh Journal of Science, i. 77 ; and Treatise on Optics, edit, citat., p. 253. 13 Philos. Transact, for 1795. 110 SENSIBILITY. change either in the size or figure of the oval spot. Again, Sir Ever- ard Home asserts, that all the ingenuity of the distinguished mecha- nician, Ramsden, was unable to decide, whether, in the adjustment of the eye, there be any alteration produced in the curvature of the cornea. These facts would alone induce a doubt of the existence of this kind of adjustment, even if we had not the additional evidence, that many animals are incapable of altering the shape of the eyeball, by the muscles at least. The cetacea, the ray amongst fishes, and the lizard amongst reptiles, have the sclerotica so inflexible as to render any variation in it impossible. With regard to many of the particular views that have been men- tioned, they are mere "cobwebs of the brain," and unworthy of serious argument. In the action of the orbicularis palpebrarum, as suggested by Dr. Monro, there is, however, something so plausible, that many persons have been misled by it. He made a set of experiments to show, that this muscle, by compressing the eyeball, causes the cornea to protrude, and thus enables the eye to see near objects more dis- tinctly. When he opened his eyelids wide, and endeavoured to read letters, which were so near the eye as to be indistinct, he failed; but when he kept the head in the same relation to the book, brought the edges of the eyelids within a quarter of an inch of each other, and made an exertion to read, he found he could see the letters distinctly. But Sir Charles Bell1 properly remarks on this experiment, that if the eyelids have any effect upon the eyeball by their approximation, it must be to flatten the cornea; and that the improvement in near vision produced by such approximation is owing to the most diver- gent rays being shut off,—as in the experiment of the pinhole through paper. Dr. Carpenter2 thinks that, so far as we can at present judge, a change in the place of the lens is the sole means of adapting the eye for distant objects; and he is disposed to believe, with Dr. Clay Wallace, Messrs. Todd and Bowman, and others, that this is effected by the action of the ciliary muscle (Fig. 287), and also, he thinks, by the erectile tissue of the ciliary processes ; for although—he remarks —no such change can be demonstrated by observation, yet it can be shown, that the contraction of the ciliary muscle would tend to draw the lens forward; and the fact, that this muscle is peculiarly powerful in the predaceous birds, which are distinguished for their great range of vision, and which have, in their circle of osseous sclerotic plates, an unusually firm point of attachment for it, he considers a strong argu- ment in favour of this view. 2. The second hypothesis, which attributes the adaptation to a change of figure in the crystalline itself, has been embraced by all who regard that body to be muscular, and therefore by Leeuwenhoek,3 Des Cartes,4 and Dr. Young.5 These muscular fibres, however, could never be excited by Dr. Young to contraction so as to change the ' Anat. and Physiology, Amer. edit, by Dr. Godman, ii. 227, New York 1897 2 Principles of Human Physiology, Amer. edit., p. 669, Philad., 1855 ' 3 Boerhaav. Prselect., § 527, torn. iv. p. 92; and Haller, Element. Physiol lib xvi. sect. 2. '' 4 °P- cit- « Op. cit. ADAPTATION OF THE EYE TO DISTANCES. Ill focal power; and their very existence is more than doubtful. The increasing density of the lens towards its centre indicates rather a cellular structure, the cells being filled with transparent matter of various degrees of concentration; and an examination into its intimate physical constitution affords no evidence of muscularity. Professor Forbes,1 of Edinburgh, embraced the view, that the adap- tation is owing to a change of figure in the crystalline; but his expla- nation of its mode of production varies from that given by preceding writers. The lens, he says, is composed of coats more firm and tena- cious, as well as more refractive towards the centre, and less so at the sides. These coats are also nearly spherical in the centre, forming a nucleus of considerable resistance. Hence he supposes, that if the lens be compressed in any manner by a uniform hydrostatic pressure, it will yield more readily in a plane at right angles to the axis of vision; and the lens will become more spheroidal, and consequently more refractive,—that is, adapted for the vision of objects at small distances. This hydrostatic pressure is believed to be conveyed from the humours of the eye, between which the lens is delicately sus- pended, and to originate in the action of the muscles that move the eyeball compressing simultaneously the tough sclerotic coat. It is somewhat singular, that on a subject where so many opportu- nities have occurred for establishing the fact definitively, such differ- ence of opinion should exist regarding the question, whether an eye from which the crystalline has been removed, as in the operation for cataract, be capable of adjusting itself to near objects. Haller2 and Knox, amongst others, decide the question affirmatively; Porterfield, Young, and Travers,3 negatively. M. Magendie, as we have seen, con- siders the great use of the crystalline to be,—to increase the bright- ness and sharpness of the image by diminishing its size. Mr. Travers again, regards the adjustment as a change of figure in the lens; not, however, from a contractile power in the part itself, but in consequence of the lamellae, of which it is composed, sliding over each other, when acted upon by external pressure; whilst upon the removal of this pressure, its elastic nature restores it to its former spherieity. The iris is conceived to be the agent in this process,—the pupillary part of the organ being, in the opinion of Mr. Travers, a proper sphincter muscle, which, when it contracts and relaxes, tends, by the intervention of the ciliary processes, to effect a change in the figure of the lens, which produces a corresponding change in its refractive powers. 3. One of the causes to which the faculty of seeing at different dis- tances has been ascribed is the contraction and dilatation of the pupil. It has been already observed, that when we look at near objects, the pupil contracts, so that the most divergent rays do not penetrate the pupil; and vision is distinct. Hence, it has been conceived probable, by De La Hire,4 Haller,5 and others, that the adjustment of the eye to 1 Proceedings of the Royal Society of Edinb., No. 25, cited in the Amer. Journ. of the Med. Sciences, Oct., 1845, p. 504. 2 Element. Physiol., lib. xvi. sect. 4. 3 A Synopsis of the Diseases of the Eye, Lond., 1824. 4 Memoir, de l'Acad. des Sciences de Paris, torn. ix. p. 620. 6 Element. Physiol., torn. v. lib. xvi., 4. 112 SENSIBILITY. various distances within the limits of distinct vision may be effected by this mechanism, in the same manner as it regulates the quantity of light admitted into the organ. Certain it is, that if we look at a row of minute objects, extending from the visual point outwards, the pupil is seen to dilate gradually as the axis of the eye recedes from the nearest object. An experiment made by the author,, on his own eye,1 when a student of medicine, has been quoted by Dr. Fleming2 as confirmatory of this view. The extract of belladonna has the power, when applied to the eyelids, of dilating the pupil. A newly prepared article was thus applied, and in the space of about twenty minutes the pupil was so much dilated, that the iris was almost invisible. From the time that preternatural dilatation occurred, objects, presented to this eye with the other closed, were seen as through a cloud. The focus was found to be at twice the distance of that of the sound organ; but, in propor- tion as the effects of the belladonna passed off* and the pupil ap- proached its natural size, vision became more and more distinct, and the focus nearer and nearer the natural. In the open air, all objects * except those near were distinctly seen; but, on entering a room, all was enveloped in mist. The catoptric experiments of Cramer are more satisfactory, perhaps, in demonstrating a change in the curvature of the lens than any that have been recorded. In viewing distant objects, the eye appeared to him to be at rest; but on viewing near objects, a special action was apparent, which, he considered, consisted in the lens being carried more forwards. That such was the fact was, indeed, shown by the following experiment. It has been already remarked,3 that when a candle is held before the eye, three distinct images are seen; the nearest and the most distant being upright, and formed respectively by reflection from the cornea and the anterior surface of the crystalline; and the one in the middle inverted, and formed by reflection from the posterior concave surface of the crystalline. When the eye is accommodated for distant vision, or is at rest, the hindmost and middle images are very near each other; but when the curvature of the lens changes, the position of the images changes; when the eye was directed to near objects, Cramer noticed that the hindmost and middle images became larger than when distant objects were regarded. This phenomenon he referred to a con- siderable increase in the curvature of the lens, and he accounts for it by the pressure exerted on the lens by the contraction of the iris. The power of accommodation he found to be lost by destruction of the iris." There is, indeed, more evidence in favour of the utility of contrac- tion and dilatation of the pupil in distinct vision, within certain limits at least, than of any of the other supposed methods of adjustment- and accordingly, the majority of opticians of the present day embrace this view of the subject; but without being able to explain satisfactorily the change in the interior of the eye effected by its movements "It seems difficult," says Sir David Brewster5—one of the latest writers— 1 Annals of Philosophy, x. 432. 2 Philosophy of Zoology, i. 187, Edinb., 1822. 3 page 79 j Budge, Memoranda der Speciellen Physiologie des Menschen, S. 346, Weimar, 1853. ADAPTATION OF THE EYE TO DISTANCES. 113 " to avoid the conclusion, that the power of adjustment depends on the mechanism, which contracts and dilates the pupil; and as this adjust- ment is independent of the variation of its aperture, it must be effected by the parts in immediate contact with the base of the iris. By con- sidering the various ways, in which the mechanism at the base of the iris may produce the adjustment, it appears to be almost certain, that the lens is removed from the retina by the contraction of the pupil." The conclusion, drawn by Sir David, does not, however, impress us with the same degree of certainty. Miiller1 thinks it most probable, that the faculty of the eye, which enables it to adjust itself to different distances, depends on an organ, which has a tendency to act by consent with the iris, but yet is in a certain degree independent of it. Reasoning per exclusionem, he thinks it most probable, that the ciliary body has this motor power, and this influence on the position of the lens; but admits, that we have no positive proof of its possessing contractility. More recently, however, as has been shown,2 the existence of a ciliary muscle has been demon- strated, which, by its contraction, may directly or indirectly advance the lens. M. Pouillet, in his lectures before the Faculte des Sciences of Paris,3 explains the matter with no little confidence by the double effect of the crystalline being composed of different layers, and the mobility of the pupil;—a view, which had been previously maintained in its essential characters by Treviranus.4 As these layers are thinner towards the axis of the crystalline than near its edges, by detaching them successively the curvature of the remainder becomes greater and greater, until the most central portion has the shape of a sphere. Hence, such an apparatus will not have one focus only, but several,— as many, in fact, as there are superposed layers ;—the foci being nearer and nearer as we approach the central spherical portion. This arrange- ment, he says, enables us to see at all distances, inasmuch as, " having an,infinite number of foci at our disposal, we can use the focus that suits the object we are desirous of viewing." If, for example, it be a near object, the pupil contracts, so as to allow the rays to fall only on the central parts; if more distant, the pupil is dilated to permit the rays to pass through a part that has a more distant focus. It is obvious, however, that in such a case, the ordinary inconve- nience of the aberration of sphericity must result; for when the pupil is dilated, the rays must pass through the more marginal, as well as the central part of the lens. M. Pouillet was aware of this difficulty, but he has not disposed of it philosophically. " It may be said that in opening the pupil widely, the light is not precluded from passing by the centre, and that a kind of curtain would be required to cover the part of the lens, which is unemployed. To this I reply, that there is no necessitv to prevent the rays from passing by the axis of the crys- talline; for what is the light, which passes through this small space, 1 Elements of Physiology, by Baly. P. v. p. 1150, June, 1839. 2 Baly and Kirkes, Recent Advances in the Physiology of Motion, the Senses, &c.,p. 24, Lond., 1848. 3 Elemens de Physique Experimentale, t. iii. p. 331, Paris, 1832. * Beitriige zur Anatom. und Physiol, der Sinnenwerkzeuge u. s. w., 1828. VOL. II.—» 114 SENSIBILITY. compared with that which passes through the great zone of the crystal- line? It may be looked upon as null." It must be admitted, with Mr. Longet,1 that if the fact of the adapta- tion of the eye to vision at different distances be received as incon- testable, the mechanism of the phenomenon must be regarded as entirely unknown; not one of the explanations offered being able to carry conviction. The whole affair is, indeed, enveloped in perplexity, and it is rendered not less so by the fact mentioned by M. Magendie, that if we take the eye of an albino animal, and direct it towards a luminous object, we find a perfect image depicted on the retina, whatever may be the distance of the object;—the image, of course, being smaller and less luminous when remote, but always distinct. Yet, in this experi- ment, the eye being dead, there can be neither contraction nor dila- tation of the pupil. This result has induced Magendie,2—and not too hastily, perhaps,—to draw the conclusion, that although theory may suggest, that there ought to be such adaptation as has been presumed and attempted to be accounted for, observation proves, that such may not be the case; and, consequently, all the speculations on the subject, however ingenious they may be, must fall to the ground. Dr. Fletcher, too, after alluding to the various hypotheses on the subject, adds:— " It appears absurd to attempt to explain a fact which has no real existence, since it has never been proved that the eyeball has any ca- pability of adapting itself to different distances, or that any such adap- tation is required."3 We are, indeed, not justified, perhaps, in admit- ting more than a slight accommodation from the contraction of the pupil in viewing near objects, effected in the mode already explained. If the accommodation existed to any material extent, it is difficult to understand, why minor degrees of short or long-sightedness should not be rectified. Sir Charles Bell4 conceives, " that the mechanism of the eye has not so great a power of adapting the eye to various distances as is generally imagined, and that much of the effect, attributed to mechanical powers, is the consequence of the motion of the pupil and the effect of light and of attention. An object looked upon, if not attended to, conveys no sensation to the mind. If one eye is weaker than the other, the object of the stronger eye alone is attended to, and the other is entirely neglected; if we look through a glass with one eye, the vision with the other is not attended to." " The mind," he adds, "not the eye, harmonizes with the state of sensation, brightening the objects to which we attend. In looking on a picture or panorama, we look to the figures, and neglect the background; or we look to the general landscape, and do not perceive the near objects. It cannot be an adaptation of the eye, but an accommodation, and association of the mind with the state of the impression." The view, which we have expressed upon the subject, is confirmed by the calculations of different investigators. From the refractive powers of the different media of the eye it was calculated by Olbers, that the difference between the focal distances of the images of an 1 Traite de Physiologie, ii. 70, Paris, 1850. 2 Precis Elementaire, i. 72. 3 Rudiments of Physiology, Part iii. p. 48, Edinburgh, 1837. * Anat. and Physiology, edit, cit., ii. 230. MYOPIC AND PRESBYOPIC EYE. 115 object at such distance that the rays are parallel, and of one at the distance of four inches, is only about 0.143 of an inch; so that the change in the distance of the retina from the lens required for vision at all distances, supposing the cornea and lens to maintain the same form, would not be more than about a line. Again:—M. de Simonoff,1 a learned Russian astronomer, asserts, that from a distance of four inches to infinity the changes in the angle of refraction are so small that the apices of luminous cones, in a properly formed eye, must always fall within the substance of the retina; and hence no variation in the shape of the eye, according to the distance of the object, can be necessary. Such facts amply justify the interrogatory of M. Biot;2— whether the aberration of the focus for different distances may not be compensated in the eye by the intimate composition of the refractive bodies, as the aberration of sphericity probably is? Yet, if this be the case, how admirable must be the construction of such an instrument! How far surpassing any effort of human ingenuity! An instrument capable of not only correcting its own aberrations of sphericity, and refrangibility, but of seeing at all distances.3 It has been before observed, that the visual point varies in different individuals. As an average, it may be assumed at eight inches from the eye. There are many, however, who, either from original confor- mation of the organ, or from the progress of age, wander largely from this average; the two extremes constituting myopy or short-sightedness, and presbyopy or long-sightedness. In the myopic or short-sighted the visual point is so close, that objects cannot be seen unless brought near the eye. This defect is owing to too great a refractive power in the transparent parts of the organ; or to too great a depth of the humours; or it may be caused by unusual convexity of the cornea or crystalline; or from the retina being too Fig. 301. Fig. 302. Myopic Vision. distant from the latter. From any one or more of these causes, the rays of light proceeding from distant objects are brought to a focus before they reach the retina, and the objects consequently are not dis- tinctly visible. (Fig. 301.) To see them distinctly, they must be placed close to the eye, in order that the rays may fall more divergently; and the focus be thrown farther back so as to impinge upon the retina. The 1 Magendie's Journal de Physiologie, torn. iv. and Precis de Physiol., i. 73. 2 Traite de Physiologie Experimental, Paris, 1816. 3 Letters of Euler, by Sir D. Brewster, Amer. edit., i. 163, New York, 1833. See, on this subject, Volkmann, Art. Sehen, in Wagner's Handworterbuch der Physiologie, 14te Lieferung, S. 295, Braunschweig, 1846; and Baly and Kirkes, Recent Advances in the Physiology of Motion, the Senses, Generation and Development, p. 20, Lond., 1848. 116 SENSIBILITY. defect may be palliated by the use of concave glasses, which render the rays, proceeding from the object, more divergent. It is by no means unfrequent in youth; and the myope has been consoled with the com- mon belief, that, in the progress of life, and in the alterations which take place in the eye from age, he is likely to see well without spec- tacles, when others of the same age may find them essential. It is probable, however, that this is, in many cases at least, a vulgar error; as we have known different myopic sexagenarians, who have not ex- perienced the slightest improvement. The presbyope, presbytic, or long-sighted, labours under an opposite defect. The visual point is much more distant than the average; and Fig. 303. Fig. 304. Presbyopic Vision. he is unable to see an object unless it is at some distance. This con- dition is owing to too feeble a refractive power in the transparent parts of the eye; to insufficient depth of the eyeball; to too close an approxi- mation between the retina and crystalline; or to too little convexity of the cornea or crystalline; so that the rays of light proceeding from a near object are not rendered sufficiently convergent to impinge upon the retina; but fall behind it. This defect, which is experienced more or less by most people after middle age, is palliated by the use of con- vex glasses, which render the rays proceeding from an object more convergent, and enable the eye to refract them to a focus farther for- ward, or on the retina. Although the presbyopic eye is unusual in youth, it is sometimes met with. A young friend, at ten or twelve years of age, was com- pelled to employ spectacles adapted to advanced life; and this was the case with several of the members of a family, to whom the arts have been largely indebted in this country. One of them, at twenty, was compelled to wear spectacles which were almost microscopes. Both the myopic and the presbyopic conditions exist in a thousand degrees; and hence it is impossible to say, d priori, what is the precise lens, that will suit any particular individual. This must be decided by trial. The opticians have their spectacles arbitrarily numbered to suit different periods of life; but each person should select for himself such as will enable him to read without effort at the usual distance. A degree of myopy may be brought on by long-protracted attention to minute and near objects, as we observe occasionally in the watchmaker and engraver; and, again, a person who has been long in the habit of looking out for distant objects, as the sailor, or the watchman at signal stations, is rendered less fitted for minute and near inspection. During the domination of Napoleon, when the conscript laws were so oppres- sive, the young men frequently induced a myopic state, by the constant SINGLE VISION. 117 use of glasses of considerable concavity;—the defect being esteemed a sufficient ground of exemption from military service. The power of bi-convex glasses is indicated by their numbers, and these numbers indicate the inches of the focal length. The numbering of the French glasses, whether presbyopic or myopic, has a much more extensive range than the British, as is shown by the following lists. Presbyopic (French) 80, 72, 60, 48, 36, 30, 24, 20, 18, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4|, 4, 3*. 3, 2|, 2, If, 1J, 1. Myopic (French) 60, 30, 20, 18, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, h AI J. S3. 31 R 93 91 O 11 11 11 1 Presbyopic (British) 48, 36, 30, 24, 20, 18, 14, 12,10, 9, 8, 7, 6, 5-|, 5, Al A 9 5 03 9 5 Ol O 2 O 13 11 *2> % °S> Z4~» zS ^1.1 ^T0"i Z: Xfi i2* JV/>/c (British) 00, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20.1 The numbers of the double convex glasses below 5, in both scales, are confined to patients who have undergone the operation for cataract. In England, the lowest power in use for presbyopia is a glass of 48 inch focus. In France, as the table shows, one of much lower power is used. It would not appear, however, that any sensible difference can be perceived between these powers in most cases, so far as assist- ance to the sight is concerned.2 In this country, a power lower than 48 inches is rarely used; but occasionally one of 60 or 80 inches is employed. Another subject, which has given rise to much disputation and ex- periment, is, why, as we have two eyes, and the image of an object is impressed upon each of them, we do not see such object double ? Smith3 and Buffon4 consider, that in infancy we do see it so; and that it is not until we have learned by experience,—by the sense of touch, for example,—that one object only exists, that we acquire the power of single vision. After the mind has thus become instructed of its error, a habit of rectification is attained, until it is ultimately effected uncon- sciously. The objections to this hypothesis are many and cogent. We are not aware of any instance on record, in which double vision has been observed in those, who, having laboured under cataract from birth, have received their sight by an operation; and we are obviously precluded from knowing the state of vision in the infant, although the simultaneous and parallel motions of the eyes, which are manifestly instinctive, and not dependent upon habit, would induce us to presume, that the images of objects—as soon as the parts have attained the ne- cessary degree of developement—are made to fall upon corresponding points of the retina. It may, also, be remarked, in favour of the in- stinctive nature of this parallel motion of the eyes, that in the blind,— although we may find much irregularity in the motions of the eyeball, owing to no necessity existing for the eyes being directed to any par- ticular point,—the eyeballs move together, unless some deranging influence is exerted. The truth is, as we have already observed, the encephalon is compelled to receive the impression as it is conveyed to 1 W. White Cooper, art. Vision, in Cyclop, of Anatomy and Physiology, iv. 1467, London, 1852. •i ibid. 3 Optics, Cambridge, 1738. 4 Memoir, de l'Academ. des Sciences, 1743. 118 SENSIBILITY. it; and even in cases, in which we are aware of an illusion, the per- ception of the illusion still exists in spite of all experience. If the finger be pressed on one side of the eyeball, an object, seen in front, will appear double, and the perception of two objects will be made by the brain, although we know from experience that one only exists. This occurs in all the various optical illusions to be presently mentioned. The effect of intoxication has been adduced in favour of this hypothe- sis. It is said that in these cases the usual train of mental association is broken in upon, and hence double vision results. The proper ex- planation, however, of this diplopia of the drunkard rests upon other grounds. The effects of inebriating substances on the brain are to interfere with all its functions; and most sensibly with the voluntary motions, which become irregularly executed. The voluntary muscles of the eye partake of this vacillation, and do not move in harmony, so that the impressions are not made on corresponding points of the retina, and double vision necessarily results. Another hypothesis has been, that although a separate impression is made upon each retina,—in consequence of the union of the optic nerves the impressions are amalgamated, and arrive at the encephalon, so as to cause but one perception. This was the opinion of Briggs,1 and Ackermann; and at one time it was generally received. Dr. Wollaston2 supposed the consentaneous motion of the eyes to be con- nected with the partial union of the optic nerves. The anatomical and physiological facts relating to the union and decussation of these nerves have already engaged us. By a reference to that subject it will be found, that a true decussation takes place between them, yet that each eye probably has its distinct nerve from origin to termination; and that no such semi-decussation, as that contended for by Dr. Wollaston, exists. These facts are unfavourable to the hypothesis of amalgamation of impressions: besides, if we press slightly on the eye, we have a double impression, although the relation of the optic nerves to each other is the same; and, moreover, the same explanation ought to apply to audi- tion, in which we have two distinct impressions, but only a single per- ception ;—yet no one conceives that the auditory nerves decussate. The fusion of the two images into one seems to be a mental operation. Another opinion has been maintained;—that we do not actually receive the perception of two impressions at the same time; and that vision consists in a rapid alternation in the use of the eyes, according as the attention is directed to one or other of them by accidental cir- cumstances. Such was the opinion of M. Dutours.3 A modification of this view was entertained by Le Cat,4 who asserts, that, although the right eye is not always the most powerful, it is most frequently employed; and Gall denies, that we use both eyes at the same time, except in the passive exercise of the function. In active vision, he asserts, we always employ one eye only,—sometimes one and some- times the other; and thus, as we receive but one impression, we neces- sarily see but one object. In support of this view, he remarks that in many animals the eyes are situate at the sides of the head, so as not to be capable of being directed together to the same object. In them, 1 Nova Visionis Theoria, Lond., 1685. * Philos. Transact, for 1824 p. 222. 5 Memoir, presentees a l'Academie des Sciences, &c., t. iii. & iv. * Op. citat' SINGLE VISION. 119 consequently, one eye alone can be used; and he considers this a pre- sumption, that such is the case in man. He remarks farther, that in many cases we use one eye by preference, in order that we may see better—as in shooting or in taking the direction of objects in a straight line; and that although, in other cases, both eyes may be open, we still use but one. In proof of this, he says, if we place a small object be- tween the eyes and a lighted body, and look at the latter, the shade does not fall between the eyes, on the root of the nose, as it ought to do if the body were looked at with both eyes; but on each eye alter- nately, according as the one or the other is directed to it; and, he adds, if, when we squint voluntarily, we see two objects, it is because one eye sees passively, whilst the other is in activity.1 Amongst numerous objections to this view of the subject, a few may be instanced. Every one must have observed how much more vividly an object is seen with both eyes than with one only. The difference according to Jurin2 is a constant quantity; and, in sound eyes of the ordinary degree of power, amounts to one-thirteenth of the whole effect. But we have experiment to show, that a distinct impression is made upon each eye. If a solar beam be admitted into a dark chamber, and be made to pass through two glasses of tolerable thickness, but of dif- ferent colours, placed close alongside each other, provided the sight be good and the eyes of equal power, the light perceived will not be of the colour of either of the glasses, but of an intermediate shade; and if this should not happen, it will be found, that the eyes are of unequal power. When such is the case, the light will be of the colour of the glass placed before the stronger eye. These results were obtained in the Cabinet de Physique of the Faculte de Medecine of Paris, by M. Magendie,3 in the presence of M. Tillaye the younger. The existence of this double impression is proved in another way. If we place any tall, slender object a few feet before us, and examine its relative situation compared with a spot on a wall in the distance, we find, that if the spot be hidden by the stick, when both eyes are open, it will become visible to each eye, when used singly; and be seen on the side of the stick corresponding to the eye employed. But Pro- fessor Wheatstone4 has instituted experiments, which place this matter entirely at rest. He has shown, that in viewing an object having length, breadth, and thickness, the perspective projections upon the two retinae differ according to the distance at which the object is placed before the eyes. If so distant, that to view it the optic axes must be parallel, the two projections are precisely similar; but if so near, that to view it the optic axes must converge, a different perspective pro- jection is presented to each eye, and these perspectives become more dissimilar as the convergence of the optic axes becomes greater. Not- withstanding this dissimilarity between the two pictures, which is in some cases very great, the object is still seen single, although not exactly resembling either of the two pictures on the retina3. 1 Adelon, Physiologie, 2de ('dit., i. 457, Paris, 1829. 2 Essay appended to Smith's Optics, Cambridge, 1738 ; and Haller, Element. Physiol., lib. xvi. 4. 3 Pr- cis, &c, i. 86. Dutours, in Mm. prt'sent'es a l'Acadtm., iii. 514, & iv. 499. 4 Philosophical Transactions, P. ii., Lond., 183b. 120 SENSIBILITY. Having thus established, that the mind perceives an object of three dimensions by means of the two dissimilar pictures projected by it on the two retinas, Mr. Wheatstone inquired what would be the visual effect of presenting simultaneously to each eye instead of the object itself its projection on a plane Fig. 305. surface as it appears to that eye ? For this purpose he imagined an instrument which he calls stereoscope. It consists of two plane mirrors, with their backs inclined to each other at an angle of 90°, near the faces of which two mono- cular pictures are so disposed, that their reflected images are seen by the two eyes, each looking into one of the mir- rors on the same plane. The experiment may, however, be Binocular vision. made sufficiently well by the subjoined figures. Fix the right eye on the right-hand figure, and the left eye on the left-hand figure; hold between the eyes, in front of the nose, the board of a duodecimo book. The figures A and B and C and D will be seen to approximate, and to run into each other; A and B represent- ing the skeleton of a truncated four-sided figure in bold relief, whilst C and D represent a depressed or receding pyramid—a fact, which shows, that the visual appreciation of solidity, of projection, or depres- sion arises from the combination in the mind of two different images. All that is necessary, in such cases, is, that the perspective drawings of the object should be an exact representation of the images as they would be impressed upon each eye by the object itself. All these facts demonstrate, that two impressions are really made in all cases,—one on each eye;—and yet the brain has perception of but one. If the law of visible direction, which Sir David Brewster has pointed out (see page 102), be adopted, the cause of single vision with two eyes must be admitted as a necessary consequence. If we are placed at one end of a room, and direct the axes of both eyes to a circular aperture in a window-shutter at the other end, although an image of this aperture may be formed in each eye, because the lines of visible direction from similar points of the one image meet the lines of visible direction from similar points of the other each pair of simi- lar points will appear as one point, and the aperture seen by one eye will exactly coincide with the aperture seen by the other. But if, when an object is seen single with both eyes, we press one eye aside, the image formed by that eye will separate from the other image, and the object will appear double; or, if the axes of both eyes be directed to a point either nearer or more remote than the aperture in the window shutter, then, in both these cases, the aperture will appear double, because the similar lines of visible direction no longer meet at SINGLE VISION. 121 the aperture.1 In Fig. 306, if we look at the object A, the more dis- tant object, B, will be seen double; and in Fig. 307, if we look at the Fig. 306. Fig. 307. Fig. 308. Binocular Vision. object B, the nearer object A will be seen double. It is not necessary, however, that the axes of the eyes should be directed accurately on an object, in order that it shall be seen single with both eyes. A whole range of objects may be seen sin- gle if their images are thrown on corre- sponding parts of the retina in both eyes, as in Fig. 308. After all, perhaps the true condition of single vision is, that the two images of an object should be formed on portions of the two retinas that are accustomed to act in concert. In cases of convergent stra- bismus, the patient does not see double; but immediately after a successful opera- tion, if the vision of the two eyes be good, he does so; and this continues until the parts of the two retinas have become ha- bituated to act in concert. In the course of the preceding remarks, it was stated, that the eyes are not always of the same power. The difference is sometimes sur- prising. M. Adelon2 mentions the case of a person, one of whose eyes required a convex glass, with a focus of five inches; the other a concave glass, with a focus of four inches. In these cases, it is important to use one unassisted eye only; as confusion must necessarily arise from 1 Optics, p. 44, in Library of Useful Knowledge, Natural Philosophy, vol. i., Lond., 1829, and Treatise on Optics, edit. cit. * Physiologie, edit, cit., i. 459. Binocular Vision. 122 SENSIBILITY. directing both to an object. This is the cause why we close one eye in looking through a telescope. The instrument has the effect of ren- dering the focal distance of the two eyes unequal, and of placing them in the same situation as if they were, originally, of different powers. From what has been said it will be understood, that if from any cause, as from a tumour pressing upon one eyeball, from morbid de- bility of the muscles, or from want of correspondence in the sensibility of the two retinas, the eyes be not properly directed to an object, dou- ble vision will be the consequence. In almost all cases, however, of distortion of the eyeballs, the image falls upon a part of one retina, which is more sensible than the portion of the other on which it falls; the consequence will be, that the mind will acquire the habit of attend- ing to the impression on one eye only; and the other may be so ne- glected, that it will assume a position to interfere as little as possible with the vision of its fellow:—so that, although at first, in squinting, there may be a double impression, vision is ultimately single. Buffon,1 who was of this opinion, affirms, that he examined the eyes of many squinters, and found that they were of unequal power; the weaker, in all cases, having turned away from its direction, and generally towards the nose, in order that fewer rays might reach it, and consequently vision be less interfered with. Yet it is always found, if the sound eye be closed, that the other resumes its proper direction; a fact which disproves the idea of De La Hire2 and others that the cause of strabis- mus or squinting is a difference of sensibility in the corresponding points of the retinas, and that the discordance in the movements of the organs occurs in order that the images may still fall upon points of the retinas that are equally sensible. According to this view, both eyes must of course act. The fact of the diverted eye resuming its proper direction when the sound one is closed is of practical application. Many of the cases of squinting that occur in infancy have been caused by irregular action in the muscles of the eyeball; so that certain of them, from accident or imitation, having been used more frequently than others, the due equilibrium has not been maintained; double vision has resulted; and the affected eye has gradually attained its full obliquity. In these cases, we can, at times, remedy the defect, by placing a bright or con- spicuous object in such a position as to exercise the enfeebled muscles; or, we can compel the whole labour of vision to be effected by one eye, a-nd thai the affected one, which, under the stimulus, will be correctly executed, and, by perseverance, the inequality may be obviated. These, indeed, are the only cases in which we can expect to afford relief; for if the defect be in the interior of the eye, in a radical want of correspondence between the retinas, or in inequality of the foci, it is irremediable. It would appear, then, that in confirmed squinting, one eye is mainly, if not solely used, and vision is single,—and that the inclina- tion of one eye inwards may be so great as to deprive it of function, or so slight as to allow the organ to receive rays from the same object 1 Mem. de l'Academie, 1743, p. 231. 2 Ibid., torn. ix. 530; Jurin. in Essay appended to Smith's Optics, § 178-194. MULTIPLE VISION WITH ONE EYE. 123 as its fellow, and although on different parts of the retina, yet they may become associated; but, in either case, it would seem, that they, who squint habitually, neglect the impressions on the distorted eye, and see with but one. It has been remarked, that the eyeball of the imperfect eye is drawn towards the nose, in order that as few rays as possible may penetrate the organ, and the vision of the sound eye be less liable to confusion. Sir Everard Home1 conceives, that it takes this direction in conse- quence of the adductor muscle being stronger, shorter, and its course more in a straight line than that of any of the other muscles;' and Sir Charles Bell2 ingeniously applies his classification of the muscles of the eye to an explanation of the fact. He asserts, that the recti mus- cles are in activity whilst attention is paid to the impression on the retina,—but that, when the attention is withdrawn, the recti are re- lieved, and the eyeball is given up to the influence of the oblique muscles, whose state of equilibrium exists when the eyeball is turned, and the pupil presented upwards and inwards. Lastly, in persons who are in the habit of making repeated celestial observations, or in those who make much use of the microscope, the attention is so entirely directed to one eye, that the other is neglected, and, in time, wanders about, so as to produce squinting at the pleasure of the individual. In these cases, the eyes become of unequal power; so that one only can be employed where distinct vision is required. Thus far our remarks have been directed to double vision, where both eyes are employed. We have now to mention a singular fact connected with double and multiple vision with one eye only. The author has distinct double vision with each eye—uniocular diplopia;— a lighted lamp, for example, presenting to one, with the other closed, two defined images, the one in advance of the other. If a hair, a needle, or an}'- small object he held before one eye—the other being closed—and within the point of distinct vision, so that the bright light of a lamp or from a window shall fall upon the object in its pas- sage to the eye, or be reflected from it—we appear to see not one object but many. This fact, when it was first observed by the author, appeared to him to have escaped the observation of opticians and phy- siologists, inasmuch as it had not been noticed in any of the works recently published on optics or physiology. On reference, however, to the excellent " System," of Smith,3 on the former subject, he found in the " Essay upon Distinct and Indistinct Vision" by Dr. Jurin, ap- pended to it, the whole phenomenon explained, and elucidated at con- siderable length. The elaborate character of the explanation is pro- bably the cause, why the fact has not been noticed by subsequent writers. The best way of trying the experiment is that suggested by Dr. Jurin. Take a parallel ruler, and opening it slightly, hold it directly before the eye, so as to look at a window or lamp through the aperture. If the ruler be held at the visual point, the aperture will appear to form one luminous line; but if it be brought nearer to 1 Philos. Transact., 1797, and Lectures on Comparative Anatomy, iii. 238, Lond., 1823. 2 Anat. and Physiol., edit, cit., ii. 235. 3 Optics, edit. cit. 124 SENSIBILITY. the eye, it will appear double; or as two luminous lines, with a dark line between them; and according as the aperture is varied—or the distance from the eye—two, three, four, five or more luminous and dark parallel lines will be perceptible. At first sight, it might seem, that this phenomenon should be referred to the diffraction or inflection, which light experiences in passing by the edges of a small body,—as the hair or needle. New- ton had long ago shown, that, when a beam of light shines upon a hair, the hair will cast several distinct shadows upon a screen, and, of course, present several images to the eye. Dr. Kittenhouse1 ex- plains, on the same principle, a curious optical appearance, noticed by Mr. Hopkinson, in which, by the inflection of light, caused by the threads of a silk handkerchief, a multiple image of a distant lamp was presented. The objections, however, to the explanation by inflection are,—that the image always appears single, if the object be not within the distance of distinct vision;—and that the same multiple image is presented, when the object is seen by reflection, as when we look at a fine line drawn upon paper; or at a fine needle held in a bright light. In this case, a considerable number of parallel images of the needle may be seen, all equally or nearly equally distinct; and not coloured. Dr. Jurin considers the phenomena to be caused by fits of easy re- fraction and reflection of light. Newton demonstrated, that the rays of light are not, in all parts of their progress, in the same disposition to be transmitted from one transparent medium into another; and that sometimes a ray, which is transmitted through the surface of the second medium, would be reflected back from that surface, if the ray had a little farther to go before it impinged upon it. This change*of disposition in the rays,—to be either transmitted by refraction, or to be reflected by the surface of a transparent medium,—he called their fits of easy refraction, and fits of easy reflection; and he showed, that these fits succeed each other alternately at very small intervals in the progress of the rays. Newton does not attempt to explain the origin of these, fits, or the cause that produces them; but it has been sug- gested, that a tolerable idea of them may be formed by supposing, that each particle of light, after its emanation from a body, revolves round an axis perpendicular to the direction of its motion, and pre- sents alternately to the line of its motion an attractive and a repulsive pole, in virtue of which it will be refracted, if the attractive pole be nearest any refracting surface on which it falls; and reflected, if the repulsive pole be nearest the surface. A less scientific notion of the hypothesis has been suggested,—by supposing a body with a sharp and a blunt end passing through space, and successively presenting its sharp and blunt ends to the line of its motion. When the sharp end encounters any soft body it penetrates it; but when the blunt end encounters the same body, it is reflected or driven back. In applying this explanation to the phenomenon in question, Dr. Jurin presumes, that the light, in passing through the humours of the eye, experiences these fits of easy refraction and easy 1 Amer. Philos. Transact., vol. ii. MULTIPLE VISION WITH ONE EYE. 125 elucidated by the marginal figure, Fig. 309. Fig. 309. Multiple Vision with One Eye. reflection. This will be Suppose a number of rays of light to proceed from the point A, and to impinge, with differ- ent degrees of obliquity, on the denser medium, B C; all the rays that are in fits of easy refrac- tion will pass through the medium to the point D; whilst those that are in fits of easy reflection, will be thrown back into the medium A B C; so that we may pre- sume, that all the rays, which fall upon the parts of the medium B C, corresponding to the bases of the dark cones, will be reflected back, whilst those that cor- respond to the bases of the light cones will pass to a focus at D. Now, if all the bundles of rays, transmitted through the surface B C, be ac- curately collected into a focus, no other consequence will arise from the other bundles of rays having been reflect- ed back, than that the focus will be less lumi- nous than it would have been had all the rays been transmitted through it. This explains why, at the distance of distinct vision, we have only a single impression made on the 6ye'. But if we approach the object A, so that the focus is not thrown,—say upon the screen R T, which may be presumed to repre- sent the retina—but behind it; the dark and light spaces will be represented upon the screen, and, of course, in concentric circles. This happens to the eye, when the hair or needle or other object is brought nearer to it than the visual point. We can thus under- stand, why concentric circles, of the nature mentioned, should be formed upon the retina; but how is it, that the objects seen preserve their linear form? Suppose a b, Fig. 310, to be a luminous cone, which in a fit of easy re- fraction has impinged upon the retina; and A B, b a, the concentric circles, corresponding to the rays that have been reflected. It is obvious, that every point of the object will be the centre of so many concentric circles on the retina; and if we ima- gine the fits of easy reflection and refraction to be the same around those points, we shall have the dark and lucid lines represented by the tangents to these circles; and hence we can comprehend why, in- stead of having one lucid line e f, we have three, separated by dark Multiple Vision with One Eye. 126 SENSIBILITY. lines parallel to themt and if the light from the luminous poir|fc be strong enough to form more lucid rings than are represented in Fig. 310, and the breadth of those rings be not too minute to be perceived, we may have the appearance of five, seven, or more lucid lines, sepa- rated by parallel dark lines. The undulatory theory of light offers another explanation of the phenomenon of fits. The waves in the luminous ether along a ray of light may meet the surface of a transparent body in different condi- tions of condensation or rarefaction, and their transmission or reflec- tion may be determined by these conditions. We proceed now to consider the advantages, which the mind derives from the possession of this sense, so pre-eminently entitled to the epi- thet intellectual. Its immediate function is to give us the sensation of light and colour. In this it cannot be supplied by any of the other senses. The action is, therefore, the result of organization; or is a "law of the constitution;" requires no education; but is exercised as soon as the organ has acquired the proper developement. Yet, occa- sionally, we meet with cases, in which the eye appears to be totally insensible to certain colours, although capable of performing the most delicate functions of vision. Sir David Brewster1 has collected several of these cases from various sources. A shoemaker of the name of Harris, at Allonby, in Cumber- land, could only distinguish black and white; and whilst a child, could not discriminate the cherries on a tree from the leaves, except by their shape and size. Two of his brothers were almost equally defective. One of them constantly mistook orange for grass green, and light green for yellow. A Mr. Scott, who describes his own case,2 mistook pink for pale blue, and full red for full green. His father, his maternal uncle, one of his sisters, and her two sons, had the same defect. A Mr. R. Tucker, son of Dr. Tucker, of Ashburton, mistakes orange for green, like one of the Harrises; and cannot distinguish blue from pink, but almost always knows yellow. He mistakes red for brown, orange for green, and indigo and violet for purple. A tailor at Plymouth, whose case is described by Mr. Harvey,3 of Plymouth, regarded the solar spectrum as consisting only of yellow and light blue; and he could dis- tinguish, with certainty, only yellow, white and gray. He regarded indigo and Prussian blue as black; and purple as a modification of blue. Green puzzled him exceedingly; the darker kinds appearing to him brown, and the lighter kinds a pale orange. On one occasion, he re- paired an article of dress with crimson instead of black silk; and on another occasion patched the elbow of a blue coat with a piece of crim- son cloth. A still more striking case is given by Dr. Nicholls4 of a person in the British navy, who purchased a blue uniform coat and waistcoat, with red breeches to match. Sir David Brewster refers to a case that fell under his own observation, where the gentleman saw only the yelhw and blue colours of the spectrum. This defect was ex- 1 Optics, edit. cit.; Letters on Natural Magic; and art. Optics, in Library of Useful Knowledge. J 2 Philos. Trans, for 1778. s Edinb phn T 4 Medico-Chirurgical Trans., vii. 477, ix. 359. transact., x. Zb5. INSENSIBILITY OF THE EYE TO COLOURS. 127 perignced by Mr. Dugald Stewart,1 who was unable to perceive any difference between the colour of the scarlet fruit of the Siberian crab and that of its leaves. Dr. Dalton,2 the chemist and philosopher,— after whom the defect has been most unjustifiably termed daltonism,— could not distinguish blue from pink by daylight; and in the solar spec- trum, the red was scarcely visible; the rest of it appearing to consist of two colours, yellow and blue. Mr. Troughton, the optician, was fully capable of appreciating only blue and yellow; and when he named colours, the terms blue and yellow corresponded to the more or less re- frangible rays:—all those that belong to the former, exciting the sensa- tion of blueness; and those that belong to the latter that of yellowness. Dr. Hays,3 who has collected the history of numerous cases of achroma- topsia,— as this defect has been termed,—and has added the history of one which fell under his own care, was led to infer, from all his re- searches : 1, that entire inability of distinguishing colours may co-exist with perfect ability to perceive the forms of objects; 2, that the defect may extend to all but one colour, and in such case the colour recog- nised is always yellow; and, 3, that the defect may extend to all but two colours, and in such case the colours recognised are always yellow and blue;—yet that this is not the fact is sufficiently shown by the ex- amples already given. Dr. Pliny Earle4 has referred to a number of cases, which came within his knowledge, and most of them under his own observation, in which the inability would seem to have been hereditary. Dr. Earle's maternal grandfather and two of his brothers were characterized by it; and among the descendants of the first men- tioned, it is met with .in seventeen.. When thus entailed, it would ap- pear to overleap, at times, one generation or more. It would appear, too, that males are more frequently affected than females. M. Cunier,5 however, has recorded a remarkable instance in which the defect oc- curred in five generations of one family, there being thirteen cases, and all females. This appears to be a remarkable exception to the rule.8 Dr. Earle observed, that the power of accurately distinguishing colours varies at different times in the same person ; and that it is not unfite- quently connected with, or accompanied by, a defect in the power of discriminating musical tones.7 The opinions of philosophers have varied regarding the cause of this singular defect in eyes otherwise sound, and capable of performing every other function of vision in the most delicate and accurate man- ner. By some, it has been presumed to arise from a deficiency in the visual organ; and by such as consider the ear to be defective in func- tion in those that are incapable of appreciating musical tones, this de- ficiency in the eye is conceived to be of an analogous nature; and the / 1 Elements of the Philosophy of the Human Mind, ch. iii. * Manchester Memoirs, v. 28. 3 Proceedings of the American Philosophical Society for August 21, 1840 ; and in Lawrence, Treatise on Diseases of the Eye, Amer. edit., p. 637, Philad., 1855. 4 American Journal of the Medical Sciences, April, 1845, p. 346. 6 Annales d'Oculistique, i. 417. 6 W. White Cooper, art. Vision, in Cyclop, of Anat. and Phys.,iv. 1454, Lond., 1852. ' For many such cases see W. White Cooper, op. cit. ; Hays, in Lawrence, op. cit. ; and Mackenzie, Practical Treatise on the Diseases of the Eye, Amer. edit, by Dr. A. Hewson, p. 881, Philad., 1855. 128 SENSIBILITY. analogy is farther exhibited by the facts, just mentioned, observed by Dr. Earle. "In the sense of vision," says Dr. Brown,1 "there is a species of defect very analogous to the want of musical ear,—a defect which consists in the difficulty, or rather the incapacity, of distinguish- ing some colours from each other—and colours which, to general observers, seem of a very opposite kind. As the want of musical ear implies no general defect of mere quickness of hearing, this visual defect, in like manner, is to be found in persons who are yet capable of distinguishing, with perfect accuracy, the form, and the greater or less brilliancy of the coloured object; and I may remark, too, in con- firmation of the opinion, that the want of musical tone depends on causes not mental but organic, that in this analogous case some at- tempts, not absolutely unsuccessful, have been made to explain the apparent confusion of colours by certain peculiarities of the external organ of sight." Dr. Dalton, who believed the affection to be seated in the physical part of the organ, has endeavoured to explain his own case, by sup- posing, that the vitreous humour is blue, and therefore absorbs a great portion of the red and other least refrangible rays; and Sir David Brewster, in the "Library of Useful Knowledge,"2 appears to think that it may depend upon a want of sensibility in the retinae, similar to that observed in the ears of those who are incapable of hearing notes above a certain pitch; but as this view is not contained in his more recent "Treatise on Optics," it is probably no longer considered by him to be satisfactory. The defect in question—difficult as it is to comprehend—has always appeared to the author to be entirely cerebral, and to strikingly re- semble, as Dr. Brown has suggested, the "want of musical ear." As we have already endeavoured to establish, that the latter is dependent upon a defective mental appreciation, the parity of the two cases will, of course, compel us to refer the visual defect, or the want of the "faculty of colouring," to the same cause. It has been remarked, that the eye in these cases exercises its function perfectly as regards the form and position of objects, and the degree of illumination of their different portions. The only defect is in the conception of colour. The nerve of sight is probably accurately impressed, and the deficiency is in the part of the brain whither the impression is conveyed, and where perception is effected, which is incapable of accurately appre- ciating those differences between rays, on which their colour rests; and this is the view taken of it by one of the most eminent philosophers of the present day, Sir J. F. W. Herschel.3 The mediate or auxiliary functions of vision are numerous • hence the elevated rank that has been assigned to it. By it, we are capable of judging, to a certain extent, of the direction, position, magnitude, distance, surface, and motion of bodies. Metaphysicians have differed greatly in their views on this subject; the majority believing, that, • 1 Lectures on the Philosophy of the Human Mind, vol. i., Boston 1826 2 Natural Philosophy, vol. i., Optics, p. 50, Lond., 1829. » Encyclopaedia Metropolitana, art. Light. See, on all this subject W White Cooper VISION—APPRECIATION OF DISTANCES. 129 without the sense of touch, the eye is incapable of forming any accu- rate judgment on these points; others, that the sense of touch is no farther necessar}' than as an auxiliary; and that a correct appreciation could be formed by sight alone. The few remarks that may be neces- sary on this subject will be deferred until the physical and other circum- stances which enable us to judge of distance, &c, have been canvassed. The direction or position of objects has already been considered, so far as regards the inverted image formed by them on the retina. The errors that arise on this point are by no means numerous, and seldom give rise to much inconvenience; yet, whenever the luminous cone meets with reflection or refraction before reaching the eye, the retina conveys erroneous information to the sensorium, and we experience an optical illusion. To ascertain the magnitude, distance, and surface of bodies, we are obliged to take into consideration several circumstances connected with the appearance of the object,—such as its apparent size; the intensity of light, shade, and colour; the convergence of the axes of the eyes; the size or position of intervening objects, &c. Porterfield1 enumerates six methods, which are employed in appreciating distance—1. The apparent magnitude of objects; 2. The vivacity of their colours; 3. The distinction of their smaller parts; 4. The necessary conformation of the eyes for seeing distinctly at different distances; 5. The direction of their axes; and 6. The interposition of objects. Dr. Brown2 reduces them to three—1. The difference of the affections of the optic nerve; 2. The different affections of the muscles employed in varying the re- fracting power of each eye, according to the distance of objects, and in producing that particular inclination of the axes of the two eyes which directs them both equally on a particular object; and 3. The previous knowledge of the distance of other objects, "which form, with that we are considering, a part of one compound perception." Lastly, Dr. Ar- nott1 enumerates four modes by which this is effected—1. The space and place occupied by objects in the field of view, measured by what is termed the visual angle. 2. The intensity of light, shade, and colour. B. The divergence of the rays of light—and 4. The convergence of the axes of the eyes. This enumeration may be adopted with some slight modification. The circumstances,in our opinion, to be considered, are:— 1. The visual angle, or that formed by two lines, which shave the ex- Fig- 311. tremities of an object and cross at the centre of the crystalline; so that the visual angle, subtended by the object, as A B, Fig. 311, is exactly equal to that subtended by its image a b on the retina. It is obvious, from this figure, that if all objects were equidistant from the eye, and of the Visual Angle. same magnitude, they would subtend the same angle; and if not of the same magnitude, the difference would 1 A Treatise on the Eye, ii. 409, London, 1759. 2 Lectures on the Philosophy of the Human Mind, vol. i., Boston, 1826. » Elements of Physics, new Amer. edit., p. 383, Philad., 1841. vol. ii.—y 130 SENSIBILITY. be accurately indicated by the difference of the visual angles subtended by them. The two arrows, however, which are of different sizes, sub- tend the same visual angle, and are alike represented on the retina by the image a b. It is clear, then, that the visual angle does not give us a correct idea of the relative magnitudes of bodies, unless we are ac- quainted with their respective distances from the eye; and, conversely, we cannot judge accurately of their distances, without being aware of their magnitudes. A man on horseback, when near us, subtends a certain visual angle; but, as he recedes from us, the angle becomes less and less; yet we always judge accurately of his size, because aware of it by experience; but if objects are at a great distance, so as not to admit of their being compared with nearer by simple vision, we are in a constant state of illusion,—irresistibly believing, that they are much smaller than they really are. This is the case with the heavenly bodies. The head of a pin held close to the eye subtends as large a visual angle as the planet Jupiter, which is one thousand two hundred and eighty- one times bigger than this earth, and is eighty-six thousand miles in diameter. In like manner, a five-cent piece, held at some distance from the eye, shuts off the sun, although its diameter is eight hundred and eighty-eight thousand miles. The sun and moon, again, by subtending nearly the same visual angle, appear to us of nearly the same size; and the illusion persists in spite of our being aware of the mathematical accuracy, with which it has been determined, that the former is ninety- six millions of miles from us, and the latter only two hundred and forty thousand. The visual angle, again subtended by an object, differs greatly according to the position of the object. A sphere has the same appearance or bulk, when held at a certain distance from the eye, what- ever may be the position in which it is viewed; and, accordingly, the visual angle, subtended by it, is always identical. Not so, however, with an oval. If held, so that the rays from one of its ends shall im- press the eye, it will occasion a circular image, and subtend a much smaller angle than if viewed sideways, when the image will be elliptical or oval. The same thing must occur with every object, whose longi- tudinal and transverse diameters differ. It is obvious, that if any such object be held in a sloping position towards the eye, it will appear more or less shortened; in the same manner as the slope of a mountain or inclined plane would appear much greater, if placed perpendicularly before the eye. This appearance is what is called foreshortening; and it may be elucidated by the following figure. Suppose a man to be standing on a level plain, with his eye at c (Fig. 312), looking down on the plain. The portion of the surface a d, which is next to him, will be seen without any fore- shortening; but if we sup- pose him to regard succes- sively the portions dffg, , , , , . . and 9 o of the plain, the angle, subtended by each portion, will diminish; so that if the ande acd be 45°, dcf will be 18°,fcg 8°, and so on;'until, at length the Fig. 312. Foreshorteninj VISION—APPRECIATION OF DISTANCES. 131 obliquit}7 will be so great, that the angle becomes inappreciable. This is the cause why, if we look obliquely upon a long avenue of trees, we are unable to see the inter- vals between the farthest in Fig- 313. the series; although that be- tween the nearest to us may be readily distinguished. In all paintings, of animals espe- cially, the principle of fore- shortening has to be rigidly attended to; and it is owing to a neglect of this that we see such numerous distorted re- presentations—of the human figure especially. It has been already stated, that objects ap- pear smaller according to their ' Perspective. distance; hence, the houses of a street, or the trees of an avenue, that are nearest to us, or in the fore- ground, form the largest images on the retina, and there is a gradual diminution, so that, if we could imagine lines to be drawn along the tops and bottoms of the objects, and to be sufficiently prolonged, they would appear to meet in a point, as 'in Fig. 313. The art which traces objects, with their various degrees of apparent diminution on account of distance, and of foreshortening on account of obliquity of position, is called perspective. 2. The intensity of light, shade, and colour.—It has been shown, that the intensity of light diminishes rapidly, according to the distance of the body from which it emanates; so that it is only one-fourth as powerful when doubly distant, one-sixteenth when quadruply distant, and so on. This fact is early recognised; and the mind avails itself of it to judge, with much accuracy, of relative distances. It is, however, a pregnant source of optical illusions. In a bright sunshine, mountains appear much nearer to us than when seen through the haze of our Indian summer} In a row of lamps along a street, if one be more luminous than the rest, it seems to be the nearest; and, in the night, we incur the strangest errors in judging of the distance of a luminous body. The sky appears nearer to the earth directly above, than it does towards the horizon; because the light from above having to pass only through the atmosphere is but slightly obstructed, whilst a portion only of that, which has to pass through the dense heteroge- neous air, near the surface of the earth, arrives at the eye. The upper part of the sky being, therefore, more luminous seems nearer; and, in the same manner, we explain, in part, why the sun and moon appear 1 A delightful season, in the southern and western parts of North America more espe- cially, generally occurring in October or November; and having nothing similar to it, so far as we are aware, in any other part of the globe. It is dependent upon some meteorological condition of the atmosphere, and occurs only when the wind is southerly, or from the warmer regions; disappearing immediately as soon as it veers to the north. By some, this phenomenon has been supposed to be caused by the large fires in the western prairies ; but the warmth that attends the haze cannot be explained on this hypothesis, independently of other sufficient objections to it. 132 SENSIBILITY. laro-er at rising and setting. In the marginal illustration we have a strfkino- illustration of the difference in apparent magnitude of two ° circles of the same Fig. 314. size; one of which re- n fleets all the rays; and .rfggHBfew the other absorbs all. ^m ^k The different degree JB A of activity of the re- gi B tina in the two cases H m causes the white circle ¥$ V to be considered—as ^j ^r estimated by Profes- ^BHH^ sor Budge1—one-fifth Apparent magnitude. ^The shade of bodies keeps pace with their intensity of light; and accordingly, the shadows of objects near us, are strongly defined;—whilst in the distance they become confused, and the light altogether so faint, that the eye at last sees an extent of distant blue mountain or plain,—"appearing bluish," says Dr. Arnott,2 "because the transparent air, through which the light must pass, has a blue tinge, and because the quantity of light arriving through the great extent of air is insufficient to exhibit the detail." "The ridge called Blue Mountains," he adds, "in Australia, and another of the same name in America, and many others elsewhere, are not really blue, for they possess all the diversity of scenery, which the finest climates can give; but to the discoverer's eye, bent on them from a distance, they all at first appeared blue, and they have ever since retained the name." As regards the Blue Ridge of America, Dr. Arnott labours under misapprehension. Within a very few miles from the whole of this extensive chain, as well as from a distance, the blue tinge is perceptible, especially when the air is dense and clear, soon after the sun has descended behind it; so that the name is as appropriate in the vicinity as it was when "the discoverer's eye was bent on it from a distance." It is obvious, that without the alternation of light and shade we should be unable to judge, by the eye, of the shape of bodies,—to distinguish a flat circle from a globe ; or any of the prominences and depressions, that are every where observable. The universe would seem to be a flat surface, the outlines of which would not even be perceptible; and the only means of discriminating objects would be by their differ- ence of colour. It is partly by attending to the varying intensity of light and shade, that the painter succeeds in representing the near as well as the distant objects in an extensive landscape: those in the fore- ground are made bold and distinct; whilst the remote prospect is made to become gradually less and less distinct, until it fades away in the distance. This part of his art is called aerial perspective. 3. Convergence of the axes.—When an object is situate at a moderate distance from us, we so direct the eyes, that if the axes were prolonged 1 Memoranda der speciellen Physiologie des Menschen, 5te Auflage, S. 321, "Weimar, 1853. " Op. cit., p. 401. VISION—APPRECIATION OF DISTANCES. 138 they would meet at it. This angle, of course, varies inversely as the distauce; so that if the axis be turned to a nearer object, the angle will be greater; if to one more distant, less. By this change in the direction of the axes the mind is capable of judging, to a certain extent, of near distances. A definite muscular effort is required for each par- ticular case; and the difference in the volition necessary to effect it enables the brain to discriminate, precisely in the same manner as it judges of the height of a body, by the muscular action required to carry the axis from one extremity of the object to the other.1 AVe have the most satisfactory evidence, that such convergence of the axes is indis- pensable for judging accurately of distance in near vision. If we fix a ring to a thread suspended from a beam, or attach it to a stand, and endeavour, with one eye closed, to pass a hook, fixed to the extremity of a rod four or five feet long, into the ring, we shall find it impracti- cable unless by accident or by touching the ring with the rod. The hook will generally be passed on the far or near side of the ring; but if we use both eyes, we can readily succeed. They, however, whose eyes are of unequal power, cannot succeed with both eyes. This is shown by the difficulty experienced by those who have lost an eye. M. Magendie2 says it sometimes takes a year, before they can form an accurate judgment of the distance of objects placed near the eye. The author has known one or two interesting examples, in which the power was never regained; notwithstanding every endeavour to train the remaining organ. It need scarcely be said, that the convergence of the axes is no guide to us in estimating objects, which are at such a distance, that the axes are nearly parallel,—as the sun and moon, or any of the celestial lumi- naries. 4. Interposition of known objects.—Another mode of estimating the magnitude or distance of objects is by a previous knowledge of the magnitude or distance of interposed or neighbouring objects; and if no such objects intervene, the judgment we form is apt to be inaccurate. This is the reason why we are so deceived as to the extent of an un- varied plain or the distance at which a ship on the ocean may be from us: it is also another cause why the sky appears to us to be nearer at the zenith than it is at the horizon. The artist avails himself of this means of judging of magnitude in his representations of colossal species of the animal or vegetable kingdom, or of the works of human labour and ingenuity,—by placing a well-known object alongside of them as a standard of comparison. Thus, the representation of an elephant or a giraffe might convey but imperfect notions of its size to the mind, with- out that of its keeper being added as a corrective. It is in consequence of the interposition of numerous objects, that we are able to judge more accurately of the size and distance of those that are on the same level with us, than when they, are either much above or much below us. The size and distance of a man on horseback are easily recognised by the methods already mentioned, when he is riding before us on a dreary plain ; the man and horse appearing more dimi- nutive, but, being seen in their usual position, they serve as mutual 1 Sir C. Bell, in Philos. Transact, for 1833. 2 Precis, &c, i. 88. 134 SENSIBILITY. sources of comparison. When, however, the same individual is viewed from an elevated height, his apparent magnitude, like that of the objects around him, is strikingly less than the reality. Beautifully and accu- rately is this effect depicted by the great dramatist:— " How fearful And dizzy 'tis to cast one's eye so low! The crows and choughs, that wing the midway air, Show scarce so gross as beetles. Half way down Hangs one that gathers samphire ; dreadful trade ! Methinks he seems no bigger than his head. The fishermen that walk upon the beach, Appear like mice ; and yon tall anchoring bark, Diminish'd to her cock; her cock a buoy Almost too small for sight." Kixg Lear. The apparent diminution in the size of objects seen from a height is not to be wholly explained by the foreshortening, which deprives us of our usual modes of judging. It is partly owing to the absence of inter- vening bodies; and still more perhaps to our not being accustomed to view objects so circumstanced. Similar remarks apply to our estimates of the size and distance of objects placed considerably above us. A cross, at the summit of a lofty steeple, does not appear more than one- fourth of its real size, making allowance for the probable distance; yet a singular anomaly occurs here :—the steeple itself seems taller than it really is; and every one supposes that it would extend much farther along the ground, if prostrated, than it would in reality. The truth, however, is, that if the steeple were laid along the ground, unsurrounded by objects to enable us to form an accurate judgment, it would appear to be much shorter than when erect, on the principles of foreshortening already explained. The cause of this small apparent magnitude of the cross and upper part of the steeple is, that they are viewed without any surrounding objects to compare with them : they, therefoie, seem to be smaller than they are; and, seeming smaller, the mind irresistibly refers them to a greater distance. For these reasons, then, it becomes neces- sary, that figures, placed on lofty columns, should be of colossal mag- nitude. It is owing partly to the intervention of bodies, that the sun and moon appear to us of greater dimensions, when rising or setting, although the visual angle, subtended by them, may be the same. " The sun and moon," says Dr. Arnott,1 " in appearance from this earth are nearly of the same size, viz.:—each occupying in the field of view about the half of a degree, or as much as is occupied by a circle of a foot in diameter, when held one hundred and twenty-five feet from the eye— which circle, therefore, at that distance, and at any time, would just hide either of them. Now, when a man sees the rising moon apparently filling up the end of a street, which he knows to be one hundred feet wide, he very naturally believes, that the moon then subtends a greater angle than usual, until the reflection occurs to him, that he is using, as a measure, a street known, indeed, to be one hundred feet wide, but of which the part concerned, owing to its distance, occupies in hi's eye a very small space. The width of the street near him may occupy sixty degrees in his field of view, and he might see from between the houses 1 Op. citat. VISION—APPRECIATION OF MOTION. 135 many broad constellations instead of the moon only; but the width of the street afar off' may not occupy, in the same field of view, the twen- tieth part of a degree, and the moon, which always occupies half a degree, will there appear comparatively large. The kind of illusion, now spoken of, is yet more remarkable, when the moon is seen rising- near still larger known objects—for instance, beyond a town or a hill which then appears within a luminous circle." Such are the chief methods by which we form our judgment of the distance and magnitude of bodies;—1st, by the visual angle—2dly, by the intensity of light, shade, and colour—3dly, by the convergence of the axes of the eyes—and 4thly, by the interposition of known objects. The eye also enables us to appreciate the motion of bodies. This it does by the movement of their images upon the retina; by the variation in the size of the image; and by the altered direction of the light in reaching the eye. If a body be projected with great force and rapidity, we are incapable of perceiving it;—as in the case of a shot fired from a gun, especially when near us. But if it be projected from a distance, as the field of view is very extensive, it is more easy to perceive it. The bombs, sent from an enemy's encampment, in the darkness of night, can be seen far in the air for some time before they fall; and afford objects for interesting speculation regarding their probable destination. To form an accurate estimation of the motion of a body, we must be ourselves still. When sailing on a river, the objects, that are stationary on the banks, appear to be moving; whilst the boat, which is in motion, seems to be at rest. Bodies, that are moving in a straight line to or from us, scarcely appear to be in motion. In such cases, the only mode we have of detecting their motion is by the gradual increase in their size and illumination when they approach us ; and the converse, when they are receding from us. If at a distance, and the visual angle be- tween the extreme points of observation be very small, the motion of an object will likewise appear extremely slow; hence the difference between a carriage dashing past us in the street, and the same object viewed from a lofty column. A balloon may be moving along at the rate of nearly one hundred miles per hour ; yet, except for its gradual diminu- tion in size and intensity of light, it may appear to be at rest; and, when bodies are extremely remote from us, however astonishing may be their velocity, it can scarcely be detected. Thus, the moon revolves round the earth at the rate of between thirty and forty miles a minute— above forty times swifter than the fleetest horse; yet her motion, during any one moment, completely escapes detection; and the remark applies still more forcibly to those luminaries, which are at a yet greater dis- tance from the earth. These are cases in which the body moves with excessive velocity, yet the image on the eye is almost stationary; but there are others in which the real motion is extremely slow and cannot be at all observed; as that of the hour-hand of a clock or watch. It will be obvious, from all the remarks that have been made regard- ing the information derived by the mind from the sense of sight, that a strictly intellectual process has to be executed, without which no judg- ment can be formed ; and that nothing can be more erroneous than the notion, at one time prevalent, that the method by which we judge of distance, figure, &c, is instinctive or dependent upon an original " law 136 SENSIBILITY. of the constitution," and totally independent of any knowledge gained through the medium of the external senses. It has already been re- marked, that metaphysicians may be considered as divided into those, who believe that, without the sense of touch, the eye would be incapable of forming any accurate judgment on these points;—and those who think, that the sense of touch is no farther necessary than as an aux- iliary, and that a correct appreciation may be formed by sight alone. Messrs. Molyneux,1 Berkeley,2 Condillac,3 &c, support the former view; MM. Gall,4 Adelon,5 &c, the latter. Of the precise condition of the visual perception during early infancy, we are of course entirely ignorant. So far as our own recollections would carry us back, we have always been able to form a correct judg- ment of magnitude, distance, and figure. Observation, however, of the habitudes of infants would seem to show, that their appreciation of these points—especially of distance—is singularly unprecise; but whether this be owing to the sense not yet having received a sufficient degree of assistance from touch, or from want of the necessary developement in the structure or functions of the eyeball or its accessory parts, we are pre- cluded from judging. The only succedaneum is the information to be obtained from those who have been blind from birth, and have been restored to sight by a surgical operation, regarding their visual sensa- tions. Although in the numerous operations of this kind, which have been performed, it might seem, that cases must have frequently occurred for examining into this question, such is not the fact; and metaphysi- cians and physiologists have generally founded their observations on the well known case described by Mr. Cheselden.6 The subject of this was a young gentleman, who was born blind, or lost his sight so early, that he had no remembrance of ever having seen; and was "couched,"—so says Cheselden,—" between thirteen and fourteen years of age." M. Magen- die7 affirms, that there is every reason to believe that the operation was not for cataract, but consisted in the incision of the pupillary membrane. It need hardly be remarked, that Cheselden must be the best possible authority on this subject. " When he first saw," says Cheselden, " he was so far from making any judgment about distances, that he thought all objects whatever touched his eyes (as he expressed it), as what he felt did his skin, and thought no objects so agreeable as those which were smooth and regular, though he could form no judgment of their shape, or guess what it was in any object that was pleasing to him. He knew not the shape of anything, nor anyone thing from another, how- ever different in shape or magnitude; but upon being told what things were, whose form he before knew from feeling, he would carefully ob- serve, that he might know them again ; but having too many objects to learn at once, he forgot many of them; and (as he said), at first he learned to know, and again forgot a thousand things in a day. At first he could bear but very little light, and the things he saw he thought 1 Locke's Essay on the Human Understanding, book ii. chap. 9. 2 Essay on Vision, 2d edit., Dublin, 1709. " Traite des Sensations Part i. 4 Sur les Fonctions du Cerveau, i. 80, Paris, 1825. 5 Physiologie de l'Homme, edit, cit., i. 466. 6 Philosophical Transactions, No. 402, p. 477, for 1728; and Anatomy of the Human Body, 13th edit., Lond., 1792. 7 Precis, &c, i. 95. VISION—APPRECIATION OF MAGNITUDE, ETC. 137 extremely large; but, upon seeing things larger, those first seen he con- ceived less, never being able to imagine any lines beyond the bounds he saw: the room he was in, he said, he knew to be but part of the house, yet he could not conceive that the whole house could look bigger." A much more interesting case, in many respects, than this, which has always appeared to us too poetical, was laid before the Koyal So- ciety of London, in 1826, by Dr. Wardrop.1 It was that of a lady born blind, who received sight at the age of forty-six, by the forma- tion of an artificial pupil. During the first months of her infancy, this lady was observed to have something peculiar in the appearance of her eyes; and, when about six months old, a Parisian oculist operated on both eyes, with the effect of complete destruction of the one, and not the slightest improvement of the other. From this time, she con- tinued totally blind, being merely able to distinguish a very light from a very dark room, but without the power of perceiving even the situa- tion of the window through which the light entered; although in sun- shine, or bright moonlight, she knew its direction: she was, therefore, in greater darkness than the boy in Cheselden's case, who knew black, white, and scarlet, apart from each other; and, when in a good light, had that degree of sight, which usually exists in an eye affected with cataract; whilst in this lady the pupil was completely shut up, so that no light could reach the retina, except such rays as could pass through the substance of the iris. After a third operation had been performed for the formation of an artificial pupil, she returned from Dr. Ward- rop's house in a carriage, with her eyes covered by only a loose piece of silk. The first thing she noticed was a hackney-coach passing by, when she exclaimed, " What is that large thing that has passed by us?" In the course of the evening she requested her brother to show her his watch, when she looked at it a considerable time, holding it close to her eye. " She was asked what she saw, and she said there was a dark and a bright side; she pointed to the hour of twelve and smiled. Her brother asked her if she saw anything more; she replied yes, and pointed to the hour of six, and to the hands of the watch. She then looked at the chain and seals, and observed that one of the seals was bright, which was the case, being a solid piece of rock crystal." On the third day, she observed the doors on the opposite side of the street, and asked if they were red. They were of an oak colour. In the evening she looked at her brother's face, and said she saw his nose; he asked her to touch it, which she did: he then slipped a handkerchief over his face, and asked her to look again, when she playfully pulled it off, and asked, "What is that?" On the thirteenth day, she walked out with her brother in the streets of London, dis- tinctly distinguishing the street from the foot pavement, and stepping from one to the other, like a person accustomed to the use of her eyes. "Eighteen days after the last operation," says Dr. Wardrop, "I at- tempted to ascertain, by a few experiments, her precise notions of the colour, size, and forms, positions, motions, and distances of external objects. As she could only see with one eye, nothing could be ascer- tained respecting the question of double vision. She evidently saw 1 Philosoph. Transact., 1S26, p. 529. 138 SENSIBILITY. the difference of colours; that is, she received and was sensible of different impressions from different colours. When pieces of paper, one and a half inch square, differently coloured, were presented to her, she not only distinguished them at once from one another, but gave a decided preference to some colours, liking yellow most, and then pale pink. It may be here mentioned, that, when desirous of examining an object, she had considerable difficulty in directing her eye to it, and finding out its position, moving her hand as well as her eye in various directions, as a person, when blindfolded or in the dark, gropes with his hand for what he wishes to touch. She also distin- guished a large from a small object, when they were both held up before her for comparison. She said she saw different forms in va- rious objects, which were shown to her. On asking what she meant by different forms, such as long, round, and square, and desiring her to draw with her finger those forms on her other hand, and then pre- senting to her eye the respective forms, she pointed to them exactly; she not only distinguished small from large objects, but knew what was meant by above and below; to prove which, a figure drawn with ink was placed before her eye, having one end broad and the other narrow, and she saw the positions as they really were, and not invert- ed [!!]. She could also perceive motions ; for when a glass of water was placed on the table before her, on approaching her hand near it, it was moved quickly to a greater distance, upon which she imme- diately said, 'You move it; you take it away.' She seemed to have the greatest difficulty in finding out the distance of any object; for, when an object was held close to her eye, she would search for it by stretching her hand far beyond its position, while on other occasions she groped close to her own face for a thing far remote from her." The particulars of this case have been given at some length, inas- much as they are regarded by Dr. Bostock1—and apparently by Dr. Wardrop himself—as strikingly confirmatory of those of Cheselden, than which we cannot imagine anything more dissimilar. It will have been noticed, that, from the very first after the reception of sight, she formed an imperfect judgment of objects, and even of distances, although she was devoid of the elements necessary for arriving at an accurate estimate of the latter,—the sight of both eyes. This was, doubtless, the chief cause of that groping for objects described by Dr. Wardrop. Of forms, too, she must have had at least an imperfect notion, for we find, that on the thirteenth day after the operation, she stepped from the elevated foot-pavement to the street, " like a person accustomed to the use of her eyes." The case is, we think, greatly in favour of the view, that the sight does not require much education to judge with tolerable accuracy of the position, magnitude, distance, surface, and motion of bodies; and that, by a combination of the methods already pointed out, or of some of them, this imperfect knowledge is obtained without the aid of any of the other senses; but is of course acquired more easily and accu- rately with their assistance, especially with that of touch. What other 1 Physiology, 3d edit., p. 703, Lond., 1836. See, also, the case of a gentleman born blind, and successfully operated on in the eighteenth year of Lis age by Dr. J. C. Franz, in Proceedings of the Royal Society, 1840-41, No. 46. VISION—APPRECIATION OF MAGNITUDE, ETC. 139 than visual impressions could have communicated to the mind of Miss Biffin—whose case was referred to under another head—the accurate and minute information she possessed regarding the bodies surround- ing her at all distances? Or how does the animal, immediately after birth, acquire its knowledge of distance ? We observe the young of certain animals, immediately after they are extruded from the uterus, turn round and embrace the maternal teat; whilst others, as the par- tridge, follow the mother in a short time after they have burst the shell. The experience required for obtaining an imperfect knowledge of dis- tance, shape, &c, must, therefore, be trifling; although an accurate acquaintance may demand numerous and careful comparisons. This first degree of knowledge is probably obtained, by comparing the visual angle with the intensity of light, shade, and colour,—the more accurate appreciation following the use of the other methods already described. That the convergence of the axes requires education is demonstrated by the case of the infant. It has been remarked, that the eyeballs harmonize instinctively in their parallel motions; but the convergence requires an effort of volition, and it is some time before it can be effected, which is probably the great cause of the mal-appre- ciation of near distances, that we notice in the infant; whilst it seems to exhibit its capability of judging more correctly of objects, that are somewhat more remote; and where less convergence, and consequently less muscular effort, is necessary. The numerous optical illusions, which we have been led to de- scribe in the progress of the preceding remarks, will render it neces- sary to refer to but few under this head. It has already been said, that we lay it down as a rule, that the progress of light to the eye is always in a straight line from the luminous object; and, accordingly, if the course of the rays be modified before they reach the organ, we fall into an optical illusion. Such modifications arise either from the reflection or refraction of the rays proceeding from the object that causes the sensation. By reflection of the rays, we experience the illusion caused by mirrors. A ray of light, K C, Fig. 259, falling upon a plane mirror, I J, is reflected back in the same line; but, as we have seen, the object does not appear to be at K, but at E. Again, a ray of light, proceeding obliquely from B, and impinging on a plane mirror at C, is reflected in the direction of C A; but to the eye at A, the object B appears to be at H, in the prolongation of the ray that reaches the eye. If the mirror be concave, the object appears magnified, provided the light from the upper part of the object, as A B, Fig. 315, be reflected to an eye at F, and that from the lower part of the object meet the other at this point. To an eye so placed, the object appears magnified and seems to be at C D, or in the prolongation of the rays which fall upon the cornea. If the mirror be convex (Fig. 316), for like reasons, the cross will seem to be smaller. C: DL-- Fig. 315. -.iE & ...-V •t-F iA B Concave Mirror. 140 SENSIBILITY. The cornea constitutes a mirror of this class, in which we have an accurate miuiature representation of objects. Rays that are refracted in passing through different media, give rise to visual illusions. We have seen, that the ray from an object at F, Fig. 259, in the pool of water, I J, does Fig. 316. not proceed into the air in the direction of F C 0, but in that of the line F C A; and if we suppose the eye to be placed at A, the object will not be seen at F, but will appear to be at/; the pool will, consequently, ap- pear shallower than it really is, by the space at which/is situate above the bottom. We Convex Mirror. can now understand why rivers appear less deep than they are, when viewed obliquely; and why the lower end of a pole, immersed in water, should, when seen obliquely, appear to be bent towards the surface. In shooting fish in the water, or in attempting to harpoon them, this source of error has to be corrected. Birds, too, that live upon the inhabitants of the water, have to learn, from experience, to obviate the optical illusion; or to descend perpendicularly upon their prey, in which di- rection, as we have seen, no refraction takes place. Similar remarks apply to fish that leap out of the streams to catch objects in the air. The Chcetodon rostratus, about six or eight inches long, frequents the sea-shores in the East Indies: when it observes a fly sitting on the plants that grow in shallow water it swims to the distance of five or six feet, and then, with surprising dexterity, ejects out of its tubular mouth a single drop of water, which never fails to strike the fly into the sea, where it soon becomes its prey.1 Hommel—a Dutch governor —put some of these fish into a tub of water, and pinned a fly on a stick within their reach. He daily saw the fish shoot at the fly, and with such dexterity, that they never failed to hit the mark.2 Pallas describes the Siozna jaculatrix as securing flies by a similar contriv- ance.3 If the light, before reaching the eye, passes through bodies of a len- ticular shape, it undergoes modifications, which have given occasion to the formation of useful instruments devised for modifying the sphere of vision. If the lens be double convex, the body, seen through it, appears larger than it is, from the illusion, so often referred to, that we always refer the object in the direction of the line that impinges upon the retina. The object, consequently, appears to be greatly augmented. (See Fig. 265.) For the same reasons an object seems smaller to the eye at A, Fig. 262, when viewed through a double concave lens. Again, if the light, before reaching the cornea, be made to pass through a diaphanous body, which is itself coloured, and consequently allows only the rays of its own colour to traverse it, the object is not seen of its proper colour, but of that of the transparent body. An impression of light continues to affect the retina for some time 1 Fleming's Philos. of Zoology, i. 195. 2 Philos. Trans., liv. 89. 3 Philos. Trans., lvi. 186; also, Mr. Sharon Turner's Sacred History of the World, Amer. edit., i. 205, New York, 1832. VISION—DURATION OF IMPRESSION OF LIGHT. 141 after the impression has ceased, certainly for the sixth part of a second.1 If, therefore, a live coal be whirled round, six or seven times in a second, it will seem to be a continuous circle of fire. It is owing to this circumstance, that meteors seem to for.m a line of light—as in the case of the falling star ; and that the same impression is conveyed by a sky-rocket in its course through the air. We have an elucidation of the same fact in the instrument or toy—called, by Dr. Paris, thauma- trope—which consists of a circle, cut out of a card, and having two silken strings attached to opposite points of its diameter: by twisting these with the finger and thumb the card may be twirled round with considerable velocity. If we make on one side a black stripe as in the marginal figure 317, and on the other side one at right angles to it, Fig. 318, and cause the card to revolve rapidly, we shall see a cross. Fig. 317. Fig. 318. Thaumatrope. And if on one side of the card a chariot is drawn—and on the other a charioteer, and the card be twirled round six or seven times in a second, the charioteer will be seen in the chariot,—the duration of the impressions on the retina being such as to cause the figures, drawn on both sides of the card, to be seen at nearly the same time. The phantas- mascope, phenakistiscope and anorthoscope, act upon similar principles.2 Ensmann3 found, that the duration of the impression of colours is different; that of the yellow continuing longest, and next the white ; that of the red being less, and of the blue least. It is by accurate attention to various optical illusions, and to the laws of the animal economy on which they are founded, that many of them can be produced in the arts at pleasure. Painting is, in truth, little more than depicting on canvass the various optical errors, which we are habitually incurring. To conclude:—the sense of sight differs materially in the scale of animals: in few is the organization more perfect or the function better executed than in man. Situate at the upper and anterior part of the body, the organ of vision is capable of directing its regards over a large extent of surface; the axes of the two organs can be converged upon objects in various situations, which cannot be done by many ani- mals; and they are very movable under the domination of a muscular apparatus of admirable arrangement. Still, the eye is not as delicately 1 D'Arcy, Memoires de l'Acad^mie des Sciences, p. 439, Paris, 1765 ; and Plateau, Annales de Chimie, &c, vol. Iviii. p. 401. 2 Miiller, Principles of Physics and Meteorology, p. 310, Philad., 1848. a Poagensdorlfs Annalen, xci. 611, and Brit, and For. Med.-Chir. Rev., January, 1856, pV236. 142 SENSIBILITY. organized as in some animals, which are capable of seeing objects at a distance that would be totally beyond the reach of the visual powers of man. Like the other senses, sight can be exerted actively and passively; hence the difference between simply seeing, and looking. In the latter, the eye is directed to the object by the proper muscles; and it is not improbable, that the nerve may be aroused to a more accurate and delicate reception of impressions, as we have reason for believing is the case in the other senses. Like them, it admits of great improvement by education. The painter, and the worker in colours are capable of nice discrimination, and detect the minutest shades of difference with great facility. In savage life, where the tracks or marks through the almost interminable forests, or over the pathless wilds, are the only guides, the greatest acuteness of vision is necessary; and, accordingly, we find the North American Indian, in this respect, eminently distin- guished. The mariner, too, accustomed to look out for land, or for a hostile sail, detects it in the distant horizon long before it can be per- ceived by the landsman, and appreciates its distance and course with signal accuracy,—education, in this case, not only communicating to his eye facility in being impressed, but improving the intellectual pro- cess, by which the estimation of distances is arrived at. F. ADDITIONAL SENSES. The five senses constitute so many special nervous systems, each concerned in its appropriate function; and, although conveying ideas of the external world to the brain, and connected with that organ, they are to a certain extent independent of it. The generality of physiolo- gists admit these five only; but some have suggested others, differing, in general, from the five, in having no organ at the surface of the body exclusively concerned in the function. Buffon regarded as a sixth sense the intense sensation experienced during the venereal act; but this can only be esteemed a peculiar variety of tact in the mucous membrane of the genital organs,—differing from ordinary tact in those parts, in requiring in both sexes a special condition of the membrane; and, in the male, one such, that the sperm, when excreted, shall make the necessary impression upon it; and, consequently, appertaining to both the external and internal sensations;—the state of the membrane being referable to the latter, and the effect of the contact of the sperm to the former. Some have spoken of a sense of heat and cold:—this has been referred to under the head of tact;—others of a muscular sense, by which we acquire a knowledge of the motions that muscular contractions give rise to, and learn to apportion the effort to the degree of effect to be produced. Animal magnetizers have suggested a sixth sense, to which man owes the capability of being acted upon by them: but this is supposititious, and the facts admit of a more ready and satisfactory explanation. A sense of hunger has been, described as situate at the upper orifice of the stomach:—a sense of thirst in the oesophagus, and a pneumatic sense in the lungs; but these are rather internal sensations. The German physiologists have suggested another sense, which they term ccencesthesis, Gemeingefuhl, Gemeinsinn, Korpergefuhl Lebenssinn, Individualitatssinn, and Selbstgefuhl ("common ADDITIONAL SENSES. 143 feeling, common sensation, bodily feeling, feeling of life, sense of life, sense of individuality, and self-feeling"). This is not seated in any particular part of the body, but over the whole system; hence termed "common." It is indicated by the lightness and buoyancy, which we occasionally experience, apparently without any adequate cause; as well as by a sense of lassitude and fatigue unconnected with muscular action or disease. To it, likewise, belong the involuntary shuddering, glow, and chilliness, experienced under like circumstances. It is mani- festly one of the numerous internal sensations, felt by the frame, and every portion of it, according as they are in a perfect state of health, or labouring under irritation or oppression; but can scarcely be re- garded as an additional or sixth sense.1 It has been supposed, that certain animals may possess other senses than the five. Of this we can have no positive evidence. We are devoid of the means of judging of their sensations; and if we meet with an additional organ, which seems adapted for such a purpose, we have nothing but conjecture to guide us. Under the sense of touch it was said, that the bat is found to be capable of avoiding obstacles placed in its way intentionally, when the eyes, nostrils, &c, have been closed up; and that it readily returns to the holes in caverns to which it is habituated. Spallanzani supposed that this was owing to its being possessed of a sixth sense. We have seen, that the circumstance is explicable by unusual delicacy of one of the external senses. Again; the accuracy with which migratory animals return to their accustomed haunts has given rise to the notion of a sense of locality. Quadrupeds, the ape not excepted, have two bones in the face, in addition to those found in man. These contain the roots of the dentes incisores, when such are present; but they also exist in animals that are destitute of teeth. They are termed ossa intermaxillaria, ossa inci- soria, and ossa labialia; and are situate, as their names import, at the anterior part of the jaw, and between the ossa maxillaria or jaw bones. Jacobson2 considers them to be an organ of sense, as they communicate with the exterior, and are largely supplied with vessels and nerves. Accordingly, this has been esteemed a sensitive apparatus, connected with the season of love in animals; and, by other naturalists, as a sense intermediate between those of taste and smell, and intended to guide the animal in the proper selection of food. It need hardly be said, that this is all imaginary. ■ M. Adelon,3 it was remarked, makes two divisions of the external sensations:—those that convey information to the mind; and those that do not. The former have engaged attention; the latter will not occupy us long. They comprise but two—itching and tickling. Both of these occur in the skin and mucous membranes, and near the com- munication of the latter with the skin; or, in other words, near the termination of the outlets which they line. Itching, however, is not 1 Purkinje, art. Ccenssthesis, in Encycl. Worterb. der Medicinisch. Wissenschaft., viii. 116, Berlin, 1832; and Miiller's Elements of Physiology, by Baly, pt. v. p. 1087, London, 1839. See, also, E. H. Weber, art. Tastsinn und das Gemeingefiihl, in Wag- ner's Handworterbuch der Physiologie, 22ste Lieferung, S. 562, Braunschweig, 1849. 2 Annales du Musee, xviii. 412. 3 Physiologie de l'Homme, 2de edit., i. 481, Paris, 1829. 144 SENSIBILITY. always an external sensation,—that is, not always caused by the contact of an external body. It frequently arises from an altered condition of the organic actions of the part in which it is experienced, as in cutaneous affections; in itching at the nose produced by irritation in the intestinal canal; itching of the glans penis in cases of calculi of the urinary bladder, &c; but commonly the sensation is caused by an extraneous body, and we are irresistibly led to scratch, no matter how it may be caused. When it arises extraneously, it can generally be readily allayed; but, when dependent upon a morbid condition of the texture of the part, it becomes a true disease, and the source of much suffering. If the itching be accompanied with a feeling of motion, or of purring in the part, it is called tingling. This kind of purring often occurs without itching. Tickling or titillation is always caused by the contact of some extra- neous substance; and is therefore a true external sensation. Although occurring in the skin, and in the commencement or termination of the mucous membranes, all parts are not equally susceptible of it; and some,—as the lining membrane of the genital organs,—are only, or chiefly, so under special circumstances. The sides, palms of the hands, and soles of the feet, are the most sensitive in this respect; not, per- haps, because the nerves are more numerous in those parts, but because, owing to thinness or suppleness of skin, or to other inappreciable cir- cumstances, they are more susceptible of this kind of excitation. AVe find, too, that individuals differ as much as the parts of the body do in this respect;—some being not ticklish, or incapable of being thrown into the spasm, which the act,—nay, even the threatening of the act,—pro- duces in others. Cases are on record, in which prolonged titillation has caused general convulsions, and even death. Le Cat1 terms it an hermaphroditic sensation, inasmuch as, whilst it excites laughter, it is insupportable; and, consequently, seems to be intermediate between pleasure and pain. b. Internal Sensations. The external sensations make us acquainted with the universe sur- rounding us; and convey to the mind a knowledge of every thing that can be, in any manner, inservient to our necessities. Such necessities have, however, to be suggested to the mind, before it reacts through the aid of the organs of prehension or otherwise on external bodies, and this is accomplished by the internal or organic sensations. Without the intervention of an external cause, every organ of the body is capable of transmitting to the encephalon a number of different impressions, many of which impel the organs to acts that are necessary not only for the preservation of the individual and of the species, but also for the perfect developement of the faculties. Such are the sensa- tions of hunger and thirst; the impulse that leads to the union of the sexes; and the feeling we have of the necessity for intermission in the exercise of the muscles, and the intellect. They have been divided into three species by some physiologists;—the first arousing, or giving impulse to, the action of organs, and warning the brain of the different 1 Traite des Sens, Paris, 1767. INTERNAL SENSATIONS. 145 necessities of the system. They have been called wants or instinctive desires} Such are hunger, thirst, the desire to evacuate the urine and faeces; that of respiration, the venereal appetite {le genesique, sens genital), accouehement, &c. They belong to those that arise, when it is necessary the organs should act.—The second occur during the action of organs. They are often obscure, but sometimes acute. Amongst these are the impressions accompanying the different excre- tions,—as of the sperm, urine, &c. (although, as we have seen, these partly belong to the external sensations); the impressions that warn us of our partial or general movements, of the progress of digestion, and of intellectual labours. The last succeed to the action of organs, especially when such action has been too long continued; hence the inward feeling of fatigue after too long exertion of the functions of the senses, of the intellectual and moral faculties, and of the organs of muscular motion; the necessity of repose after prolonged muscular exer- tion ; and of sleep, to recruit the nervous system, and to fit it for the exertions it has to make during the waking condition. The mode in which these sensations are effected is analogous to that of the external sensations. There is an impression on the part to which the sensation is referred; an action of perception accomplished by the encephalon; and one of transmission, executed by a nerve pass- ing between the two. The last two actions are probably executed in the same manner as in the external sensations. The first, or the mode in which the impression is effected, and the character of the impression itself, are more obscure. In the external sensations, we can refer the impression to a known irritant,—special in some of the senses; more general in others. We know, that light impresses the retina;—aerial undulations the acoustic nerve, &c; but, in the internal sensations or sentiments, as some of the French writers term them, the source of the irritation is in some modified action of the part itself, in the very tissue of the organ, and hence the result is said to be organic. In the internal sensation of hunger, for example, the impression is engendered in the organ,—how, we know not,—is thence conveyed to the brain, and the sensation is not effected until the latter has acted. The same may be said of all the internal sensations. They differ, in other re- spects, also, from the external. Whilst the latter may be entirely passive, or rendered active by volition, without either action being the cause of particular pleasure or inconvenience, the former are little influenced by volition. Constituting the wants—the instinctive de- sires—which impel to acts, that are necessary for the preservation and full developement of the individual and of the species, such in- dependence is of course essential. On many of them, however, habit or accustomed volition has a certain degree of influence; and they can unquestionably be augmented or moderated by licentious indulgence or restraint. The influence of habit is exemplified by the regularity with which the appetite returns at stated intervals ; and by the differ- ence between that of the gourmand and of the temperate individual. It is most strikingly evidenced, however, in its influence over the 1 Adelon, art. Besoins, in Diet, de Medecine, i. 367, Paris, 1821; and Physiologie de l'Homme, i. 482. VOL. II.—10 146 SENSIBILITY. moral wants; which may even spring up from social indulgence, and hence are not instinctive or organic. We are every day compelled to witness the striking difference between the individual who prac- tises restraint upon his wrants, and the libertine, who, like the animals surrounding him, gives unbridled sway to his natural and acquired appetites. All the internal sensations, when satisfied or responded to in mode- ration, communicate a feeling of pleasure; but if resisted, pain results. If hunger be,prolonged, there is a general feeling of uneasiness, which rapidly abates after food is received into the stomach; but if satiety he produced, uneasiness follows; and this applies to all the appetites or wants. The special internal sensations will engage us, when the func- tions to which they belong fall under consideration. Like the external sensations, they must, of course, administer to the intellect, to an extent which will be seen hereafter. Their influence and nature were en- tirely neglected until of comparatively late years, when attention was directed to them chiefly through the labours of MM. Cabanis1 and of Destutt-Tracy ;3 and they now form subjects for interesting speculation, with the metaphysician more especially. The morbid sensations belong more particularly to pathology; a brief notice of them will consequently be all that is necessary here. They are comprised under the term pain. In its enlarged significa- tion, this word, as is well known, means every uneasy or disagreeable sensation or moral affection;—thus including sadness, anger, terror, as well as the painful impressions felt in the extremities or trunks of the nerves. It is the latter only or physical pain that concerns us at present. Like every other sensation, although it may be referred exclusively to the part impressed, pain requires the intervention of the encephalon; for if the nerves, proceeding from a part to that organ, be cut, tied, compressed, or stupefied by narcotics; or if the action of the brain itself be blunted from any cause, as by the use of opium, ether, or chloroform, or by any compression, accidental or other, the sensation is no longer experienced. We can thus under- stand why pain is felt less during sleep; and the astonishing cases of resistance to pain, witnessed in the lunatic, and in religious or other enthusiasts who have been subjected to bodily torture. An opposite condition of the nervous system is the cause of the great sensibility to impressions in the nervous and hysterical. It is obvious, that pain may be either an external or internal sensa- tion, according as the cause of irritation is extraneous, or seated in the tissue of organs; and that it must vary considerably, both as re- gards the precise irritant, and trie part affected; hence the difference between the pain caused by a burn, and that by a cutting instrument; and the immense variety of pains to which the human frame is sub- ject, and the attentive study of which is so indispensable to the patho- logist. So much for the sensations. These, we have seen, are innumerable, for each sense is capable of myriads of different impressions. We now 1 Rapport du Physique et du Morale de l'Homme, torn. ii. Paris 1802 2 Elemens d'Ideologie, 2de edit., Paris, 1804. MENTAL FACULTIES. 147 pass to the consideration of those functions that enable man—although worse provided with means of defence and offence than the beasts sur- rounding him, and possessing no covering to protect him from the summer's heat or the winter's cold—to provide himself means of de- fence ; to render the animals around him subservient to his use; to cover his nakedness, and protect himself against atmospheric changes; to devise mechanical arts; to fathom the laws, that govern the bodies by which he is surrounded, and tb establish himself undisputed mas- ter of the earth. G. MENTAL FACULTIES. The external senses convey to the brain the different impressions made upon them by surrounding bodies; but, of themselves, they would be unable to instruct the mind regarding the universe. It is necessary, that the brain should act before any perception of them can exist. The mental faculties, in other words, convert the impressions into ideas. The internal sensations, on the other hand, consist, as we have seen, of the numerous wants and appetites necessary for the pre- servation of the individual, and the species. In addition to these, man possesses another series of faculties, which influence his character and disposition, and direct his social existence: these are the affective or emotive faculties or faculties of the heart. The study of these different mental and moral phenomena constitutes what has been called psycho- logy,—so termed from an idea, that they are exclusively dependent upon the mind. The notion was, at one time, universal, and hence the appellation metaphysician, applied to such as were considered to proceed in their investigations beyond what was physical, material, or corporeal. There is no subject, which has given occasion to so much excite- ment and controversy, as that of the connexion of the mental faculties with the encephalon. " It has unfortunately happened," says Dr. Bos- tock,1 "that this subject, which is one of great interest and curiosity, has seldom been viewed with that philosophical spirit which should always direct our investigations, and by which alone we can expect to arrive at truth. It is admitted, that certain errors may be so inter- woven with our accustomed associations on topics connected with morals and religion, as to render it doubtful, on some occasions, how far we ought to attempt their removal; but if this concession be made on the one hand, it is incumbent upon us, on the other, not to inflame the prejudices, which may exist on these topics, but to use our endeavours to correct all undue excitement, and thus to bring the mind into that tranquil state, which may enable it to receive truth without fear of injury." In such a spirit ought every discussion on the subject to be conducted; and in such a spirit will the few remarks that follow be offered. The chief opinions, which have been indulged on the subject are,— 1st. That all the mental phenomena are immaterial, and the exclusive product of the mind. 2dly. That the sentient principle within us re- quires the intervention of an organ, through which it acts; in other 1 Physiology, 3d edit., p. 744, Lond., 1836. 148 ^ SENSIBILITY. words, that mind is a principle superadded to organization; and 3dly. That where there is no organization there is no perception;—that wherever an organized structure, like the brain, exists, perception exists; that where the organization is imperfect, perception is imper- fect ; where the organization is sound and vigorous, perception is clear and vigorous; where it is impaired, perception is impaired; and that when organization ceases perception ceases also. This last view is materialism. It supposes, that a certain condition of matter is capable of thinking, reasoning, and understanding. The doctrine,—that our intellectual and moral acts are superadded on organization, and that there is an organ concerned in their mani- festation, is the one embraced by the generality of physiologists, and is most consistent with reason and analogy: it is but justice, however, to admit, that the views of those, who consider that a certain organi- zation produces thought, are not deserving of the anathemas that have been directed against them on the score of irreligion. The charge would rather apply to those who doubt the power of Omnipotence to endow matter with such attributes. Were the mental and moral phe- nomena the exclusive products of the immaterial principle within us, they would hardly form subjects for physiological inquiry. That they are allied to organization is inferred for the following reasons. As they constitute so many functions, were they not provided with an organ or organs, they would form so many exceptions;—each of the sensations requiring an organ for its accomplishment. Again, our in- ward feeling induces us to refer them to a particular part of the frame; whilst thought appears to be effected within the head, the chief ex- pressions of the passions are felt in the region of the heart or stomach. The faculties, moreover, are not the same in every individual. One man is a poet; another a mathematician; or one is benevolent, another cruel. If these faculties were the exclusive product of the mind, and not to be ascribed to diversity of organization, we should have to admit, that each individual has a different immaterial princi- ple, and of course, that there must be as many kinds as there are in- dividuals. Lastly. The faculties vary in the same individual accord- ing to circumstances. They are not the same in the child as in the adult; in the adult as in one advanced in life; in health as in disease; in waking as in sleep. During an attack of fever they become tem- porarily deranged ; and are permanently so in all the varieties of in- sanity.1 These facts are inexplicable under the doctrine, that they are the exclusive product of the mind or immaterial principle. An immaterial or spiritual principle ought to be immutable; yet we should have to suppose it capable of alteration; of growing with the growth of the body, and of becoming old with it; of being°awake or asleep; sound or diseased. All these modifications must be caused by vary- ing organization—of the brain in particular. We may conclude, then, that the intellectual and moral faculties are not the exclusive product of the mind; that they require the interven- tion of an organ; and that this organ is the encephalon, or a part of 1 Adelon, art. Encephale, Diet, de Medecine, vol. vii.; and Physiologie de l'Homme, torn. i. edit. cit. ORGAN OF THE MENTAL FACULTIES^ 149 it—the cerebrum or brain—is announced by many circumstances. In the first place, they are phenomena of sensibility, and hence we should be disposed to refer them to a nervous organ; and, being the most ele- vated phenomena of the kind, to the highest of the nervous organs. In the second place, inward feeling impels us to refer them thither. We not only feel the process there, during meditation; but the sense of fatigue, which succeeds to hard study, is felt there likewise. The brain, again, must be in a state of integrity, otherwise the faculties are deranged; or, for the time, abolished. In fever, it becomes affected directly or indirectly, and the consequence is perversion of the intel- lect, in the form of delirium. If the organ be more permanently dis- ordered, as by the pressure of an exostosis or tumour, or by some alteration in its structure or functions—less appreciable in its nature— insanity, in some form, may be the result. In serious accidents to the encephalon, we observe the importance of the cerebrum to the proper exercise of the mental faculties clearly evinced. A man falls from a height, and fractures his skull. The consequence is depression of a portion of bone, which exerts a degree of compression upon the brain; or extravasation of blood from some of the encephalic vessels attended with similar results. From the mo- ment of the infliction of the injury, the whole of the mental and moral manifestations are suspended, and do not return until the compressing cause is removed by the operation of the trephine. M. Richerand cites the case of a female, who had a portion of the brain accidentally exposed, and in whom it was found, that pressing on the organ com- pletely suspended consciousness, which was not restored until the pressure was removed. A similar case occurred to Professor Wistar; and another is related by M. Lepelletier.1 A patient of a M. Pier- quien had an extensive caries of the os frontis, with perforation of the bone, which exposed the brain covered by its membranes. When she slept soundly, the organ sank down; when she dreamed, or spoke with feeling, turgescence and marked oscillations were perceptible; when the brain was pressed upon, she stopped in the middle of a sen- tence or a word; and when the pressure was removed, she resumed the conversation, without any recollection of the experiment to which she had been subjected. An important difference in the effect is, how- ever, noticed in such cases according to the suddenness or tardiness with which the pressure is made. Whilst a sudden compression suspends the intellectual and moral manifestations, slow pressure, produced by the gradual formation of a tumour, may exist without exhibiting, in any manner, the evidences of its presence. Accord- ingly, the anatomist is at times surprised to discover such morbid formations in the brains of persons who have never laboured under any mental aberration. A negative argument in favour of this function of the brain has been deduced from the fact, that disease of other portions of the body, even of the principal organs, may exist and pass on to a fatal termi- nation, leaving those faculties almost unimpaired. Such is proverbi- ally the case with phthisis pulmonalis; the subject of which may be 1 Physiologie Medicale, &c, iii. 242, Paris, 1832. 150 SENSIBILITY. flattering himself with hopes never to be realized, and devising schemes of future aggrandizement and pleasure until within a few hours of his dissolution. The intellectual faculties differ in each individual, and vary mate- rially with the sex. The brain is, in all these cases, equally different. Much may depend upon education ; but it may, we think, be laid down as an incontrovertible position, that there is an original difference in the cerebral organization of the man of genius and of him who is less gifted; and that, as a general rule, in the former the brain is much more developed than in the latter. Whilst the brain of the man of intellect may measure from nineteen to twenty-two inches in circum- ference, that of the idiot frequently does not exceed thirteen, or is not greater than in the child one year old. It was an ancient observation, that a large developement of the anterior and superior parts of the head is a characteristic of genius; and, accordingly, we find, that all the statues of the sages and heroes of antiquity are represented with high and prominent foreheads. In the older poets, we meet with many evidences, that the height of the forehead was regarded as an index of the intellectual or moral character of the individual. Thus Shakspeare:— " We shall lose our time, And all be turn'd to barnacles, or to apes, With foreheads villanous low." Caliban, in " Tempest."—Act iv. And again:— "Ay, but her forehead's low, and mine's as high." Julia, in the " Two Gentlemen of Verona."—Act iv. The relation between the size of the head and the mental manifesta- tions has, indeed, interwoven itself into our ordinary modes of speech. "Let it not be believed," says a distinguished writer,1 "an affair of accident, that a head of considerable dimensions is found, from time to time, to coincide with a distinguished genius. Although the amour propre may object, the law is general. I have neither met in antiquity, nor in modern times a man of vast genius, whose head ought not to be ranged in the latter class, which I have just established, especially if attention be paid to the great developement of the forehead. Look at the busts and engravings of Homer, Socrates, Plato, Demosthenes, Pliny, Bacon, Sully, Galileo, Montaigne, Corneille, Racine, Bossuet, Newton, Leibnitz, Locke, Pascal, Boerhaave, Haller, Montesquieu, Voltaire, J. J. Rousseau, Franklin, Diderot, Stoll, Kant, Schiller, &c." Yet we are not always accurate in estimating the size of the brain from the developement of the head. Dr. Sewall2 has clearly shown, that skulls of the same dimensions, as measured by the craniometer, differ largely as to the quantity of cerebral substance, which they are' capable of containing. With the assistance of Dr. Thomas P. Jones, of Washington, and of Professor Ruggles, of the Columbian College/he instituted various experiments. In the first series, he ascertained the volume of each skull, brain included: in the second series, the volume of the brain alone or the capacity of the cerebral cavity; and in order 1 Gall, Sur les Fonctions du Cerveau, ii. 342, Paris, 1825. 2 An Examination of Phrenology, in Two Lectures, 2d edit., p. 66, Boston, 1839. THE BRAIN THE ORGAN OF THE MENTAL FACULTIES. 151 to render the difference in capacity more obvious, the volume of each skull, brain included, was reduced to the dimensions of 70 fluidounces. The results of the experiments on five skulls, delineated in the plates of Dr. Sewall's work, were as follows:— Volume of Skull, Brain included. Volume of Brain. Plate II......70 oz. . . . 56-22 oz. HI......do. 51-72 IV......do. 46-21 V......do. 34-79 VII......do. 25-33 In two of these skulls, consequently, of the same external dimen- sions, there was a difference in the volume of brain of 31*89 oz. Dr. Sewall inferred from his observations, that no phrenologist, however experienced, can, by any inspection of the living head, ascertain whether a person has a skull of one inch or one-eighth of an inch in thickness; or whether he has 56*22 ounces of brain, or only 25*33 ounces. To the view, that the mental capacity is in a ratio with the size of the brain, there must be numerous exceptions; for, independently of bulk, there may obviously be an organization productive of results, in which the largely developed organ may be greatly deficient. Size is only one of the elements of activity of an organ. "Whilst there is an evident connexion," says a recent writer,1 "between a large quantity of cerebral matter, and a highly developed intellect, the quality of the mind and that of the brain-substance may also be supposed to have a close relation to each other. In great power of action a large muscle is needed, but for vigorous and well-adjusted muscular movement a certain quality of fibre is also necessary to give full scope to the nervous power. It is impossible to determine what the peculiarity in quality is; but some idea of the great influence which it may possess in the exercise of the two great vital forces, the muscular and nervous, may be gained from comparing the energy and action of a well-bred horse, with one of those which, in the language of the turf, shows little or no breeding. The actual amount of muscular or nervous fibre may be the same in both, or it may be less in the horse of good breeding than in the other, yet the former does his work, and endures fatigue better." The difference between the moral of the male a*nd the female is signal; and there is no less in the shape of the encephalon in the two sexes. Ob- servation, not only by anatomists but by sculptors and painters, shows, that the superior and anterior parts of the brain are less developed in the female, whose forehead is, therefore, as a general rule, smaller; whilst the posterior are larger. In the system of Gall, the anterior and superior parts are considered to be connected with the intellectual manifestations, which are more active in man; whilst the posterior are concerned in the softer feelings, which predominate in the character of the female. The mental and moral faculties vary, also, in the same individual, according to age, health, and disease; and in the waking and sleeping state. In all these conditions, we have reason to believe the state of the encephalon is as various. The anatomist notices a manifest 1 Todd and Bowman, The Physiological Anatomy and Physiology of Man, p. 262, Lond., 1845. 152 SENSIBILITY. difference between its organization in the infant and in the adult or aged. Like the other organs of the body, it is gradually developed until the middle period of life; after which it decays with the rest of the frame. Our acquaintance with the minute organization of the body does not enable us to say on what changes these differences are dependent. AYe see them only in their results. By the minutest exa- mination of the special nerves of sense we are incapable of saying, why one should appreciate the contact of sapid bodies, another that of light, &c. During sleep, again, in which the functions of the brain are more or less suspended, the condition of the organ is modified; and mania or delirium probably never occurs without the physical condition of the brain having undergone some change, directly or indirectly. It is true, that, on careful examination of the brains of the insane, it has often happened, that no morbid appearance has presented itself; but the same thing has occurred on inspecting those who have died of apoplexy or paralysis, in which not a doubt is entertained that the cause is seated in the encephalon, and that it consists in a physical alteration of its tissue. These are a few of the cases which make us sensible of the limited nature of our powers of observation. They by no means encourage, in the most sceptical, the belief, that the tissue of the organ is not implicated. The investigations of the morbid anato- mist, consequently, afford us few data on which to form our opinions on this subject. The effect of intoxicating substances is mainly exerted on the brain. When taken in moderation, all the faculties are excited; but if pushed too far, the intellectual and moral manifestations become perverted. This can only be through their action on the cerebral organ. We can thus understand how regimen may cause important modifications in the brain. Climate has probably a similar influence; hence the difference between the characters of different nations and races. The skull of the Mongol is different from that of the Kelto-Goth or of the Ethiopian; and the brain, as well as its functions, exhibits equal diversity. Again,_ it has been argued, that the facts noticed in the animal king- dom are in favour of the brain being the organ concerned in the men- tal manifestations; that if each animal species has its own psychology, in each the encephalon has a special organization ; and that in those which exhibit superior powers, the brain is found larger, and more com- plicated. To a great extent this is true. Nothing, indeed, seems more erroneous than the notion, that even sensibility to pain is equal in every variety of the animal creation. As we descend in the scale, the nervous system is found becoming less and less complicated; until ultimately it assumes the simplest original character, which laid the foundation for one of the divisions of Sir Charles Bell's system; and although it is impossible to change places with the animal, we have the strongest reasons for believing, that the sensibility diminishes as we descend; and that the feeling, expressed by the poet, that the beetle, which we tread upon— " In corporal sufferance finds a pang as great As when a giant dies"— however humane it may be, is physiologically untrue. The phenomena in favour of this view which present themselves to the naturalist are THE BRAIN THE ORGAN OF THE MENTAL FACULTIES. 153 numerous and interesting; and afford signal evidence of creative wis- dom in endowing the frames of those beings of the animal kingdom, that are most exposed to injury and torture, with a less sensible organi- zation. The frog continues sitting, apparently unconcerned, for hours after it has been eviscerated; the tortoise walks about after having lost its head ; and the divisions of the polypus, made by the knife, form so many distinct animals. Redi removed the whole of the brain of a common land tortoise : the eyes closed to open no more; but the ani- mal walked as before,—groping, as it were, its way for want of vision. It lived nearly six months. All have noticed the independence of the parts of a wasp, after the head has been severed from the body. It will try to bite, and, for a considerable time, the abdomen will attempt to sting. An illustrative instance of the kind occurred to Dr. Harlan.1 He cut off the head of a rattlesnake; and, grasping the part of the neck attached to the head with his finger and thumb, the head twisted itself violently, endeavouring to strike him with its fangs. A live rabbit was presented to the head, which immediately plunged its fangs deep into the animal; and when the tail of the snake was laid hold of, the headless neck was bent quickly round as if to strike the experi- menter. The experiments of Dr. Le Conte,2 of Savannah, Georgia, and of Dr. Bennet Dowler,3 of New Orleans, on the Alligator—crocodilus lucius—exhibit like results, and would lead to the inference, that in that animal, phenomena essentially resembling those, which in the upper classes of animals are referable to the encephalon, may be more diffused in their origin. In one experiment by the latter gentleman, and Dr. Young, aided by Mr. Barbot, the head of the animal, for more than an hour after decollation, exhibited that it possessed sensation, perception, vision, passion, and voluntary motion. "It saw its ene- mies; opened its mouth to bite at the proper time ; and nictated when a foreign body approached the eye;" and for three or four hours the headless trunk, during extensive mutilations by two operators, " mani- fested, in a still higher degree, sensation, intelligence, definite, well- directed muscular actions. There was, as usual, a complete loss of progressive or forward motion. The test used to elicit sensation and voluntary movements were pinching, puncturing and burning. Its sensibility and motions appeared to be nearly as acute, quick and varied as in the unmutilated animal. The direction of the limbs was not such as could be deemed habitual, as in walking and swimming. Some of these motions are of difficult execution in the entire animal from its anatomical conformation, such as reaching up between the shoulders or hips to remove an irritant." In another experiment performed in the presence of Drs. Cartwright, Smith, Nutt, Powell, Hire, Mr. Barbot, and Professor Forshey—in which decollation was practised with a dull hatchet, and, in consequence, the hemorrhage was not great, although considerable—Dr. Dowler carried the handle of a knife towards the eye, to ascertain whether it would wink; " whereupon the ferocious, separated head" sprang up from the 1 Medical and Physical Researches, p. 503, Philad., 1835. 2 New York Journal of Medicine, Nov., 1845, p. 335. 3 Contributions to Physiology, New Orleans, 1849. 154 SENSIBILITY. table with great force at him, passing very near his breast, which re- ceived several drops of blood ; and then alighted upon the floor from six to eight feet distant from its original position. It missed him be- cause he was standing at the side, and not in front of the head. " For about two hours,"—says Dr. Dowler—" the headless trunk exhibited such phenomena as are usually attributed to the brain,—namely, sen- sation, volition, and intelligential motion, as tested by the application of bits of ignited paper, wounds, and the like, whereupon the usual indi- cants of pain were elicited with great promptness and precision: it trembled, receded, rolled over, curved, placed its limbs accurately to the exact spot, and removed the offending cause. In certain places, this was exceedingly difficult, as on the spine between or near the shoulders or hips. It always used the limb the best adapted for the purpose. If the fire was too remote, as when applied to the tail, the whole body was thrown into the most favourable position for the pur- pose of reaching and removing the same. If the fire was placed on the table, in a position to annoy, yet without touching, the animal—as if endowed with sight—reached, and always acpurately, to the exact spot, and either extinguished the fire or removed it. As upon former occasions, if the animal found that the fire was continued at the same spot, and that it could not remove it, which was sometimes the case, owing to continuous or repeated applications, and carefully manoeu- vring, it curved the body,—scratched violently, manoeuvred skilfully, and then, as a last resort, rolled quite over, laterally, always from, never towards the fire and operator." Still, the position, that in man and the upper classes of animals, the brain is the organ through which the mind acts in the production of the different mental and moral manifestations, can scarcely be contested.1 Yet, amongst those who admit the accuracy of this con- clusion, a difference of sentiment exists,—some conceiving that other organs participate in the function. To each of the known tempera- ments as many intellectual and moral dispositions have been ascribed. It has been affirmed, that if the brain be manifestly the organ of intel- lect the passions must be referred to the organs of internal or organic life; whilst others have regarded the brain as a great central apparatus for the reception and elaboration of the different impressions made upon the external senses;—thus conceiving the latter to be direct agents in the execution of the function, as well as the brain. The influence of the temperaments upon the mental and bodily powers is much less invoked at the present day than it was of old. The ancients esteemed organized bodies to be an assemblage of ele- ments, endowed with different qualities, but associated and combined so as to moderate and temper each other. Modern physiologists mean by temperament the reaction of the different organs of the body upon each other consistently with health; so that if one set or apparatus of organs predominates, the effect of such predominance may, it is con- ceived, be exerted on the whole economy. In the description of the temperaments in different authors we find a particular character of 1 Gall, Sur les Fonctions du Cerveau, ii. 69, Paris, 1825; Adelon, art. Encephale, Diet, de Medec, vii. 517; and Physiologie de l'Homme, ed. cit., i. 496. ENCEPHALIC SEAT OF THE PASSIONS. 155 intellectual and moral faculties assigned to each. The man of sanguine temperament is described as of ready conception, retentive memory, and lively imagination; inclined to pleasure, and generally of a good disposition; but inconstant and restless. He of the bilious, on the other hand, is said to be hasty, violent, ambitious, and self-willed; whilst the lymphatic temperament bestows feeble passions; cold imagination; tendency to idleness ; and the melancholic disposes to dulness of con- ception, and to sadness and moroseness of disposition. M. Gall1 has animadverted on this assignment of any intellectual or moral faculty to temperament. If we look abroad, he affirms, we find the exceptions more numerous than the rule itself; so numerous, indeed, as to pre- clude us from establishing any law on the subject. Moreover, the idiot, who possesses a temperament like other persons, has no intel- lectual faculties. The temperament, doubtless, influences the brain within certain limits, as it does other functions: this, he suggests, it probably does by impressing them with a character of energy or of languor, but without, in any respect, regulating the intellectual sphere of the individual. Bichat,2 again, maintained, that whilst the encephalon is evidently the seat of the intellectual functions, the organic nervous system, and, consequently, the different organs of nutrition, which are supplied by it, are the seat of emotions or passions. That distinguished physiolo- gist, than whom, as M. Corvisart wrote to the First Consul, on an- nouncing his death, upersonne en sipeu de temps n'a fait tant de choses et aussi Men,"3 rests his views upon the following considerations:—1st. That while inward feeling induces us to refer intellectual acts to the brain, the passions are referred to the viscera of the thorax or abdo- men. 2dly. That the effects of intellectual labour are referred to the encephalon, as indicated by redness and heat of face, and beating of the temporal arteries in violent mental contentions, &c.; and whilst the passions affect the organic functions, the heart is oppressed, and its pulsations are retarded or suspended; the respiration becomes hurried and interrupted; the digestion impeded or deranged, &c.; and 3dly. That whilst our gestures and language refer intellect to the encepha- lon, they refer emotions to the nutritive organs. If we wish to express any action of the mind, or are desirous of recalling something that has escaped the memory, the hand is carried to the head ; and we are in the habit of designating a strong or weak intellect as a " strong or weak head;" or we say, that the possessor has "much or little brain." On the other hand, if desirous of depicting the passions, the hand is carried to the region of the stomach or heart; and the possessor of benevolent or uncharitable sentiments is said to have a good or a bad heart. Bichat properly adds, that this idea is not novel, inasmuch as the ancients conceived the seat of the passions to be in the epigastric centre;—that is, in the nervous plexuses situate in that region. He remarks that amidst the varieties presented by the passions, according to age, sex, temperament, idiosyncrasy, regimen, climate, and disease, there is always a ratio between them and the degree of predominance 1 Op. citat., ii. 140. 2 Sur la Vie et la Mort, Part, i., Paris, 1806. 8 Lloge de Xavier Bichat, par Miquel, p. 58, Paris, 1823. 156 SENSIBILITY. of the different nutritive apparatuses; and he concludes with a deduc- tion, which ought not to have been hazarded without full reflection,— that as the functions of the nutritive organs, in which he ranges the passions, are involuntary, and consequently uninfluenced by educa- tion, education can have no influence over the passions, and the dispo- sition is consequently incapable of modification. The answer of MM. Gall1 and Adelon2 to the views of Bichat appears to us to be irrefragable. How can we conceive, that viscera, whose functions are known, and which differ so much from each other, are agents of moral acts ? The passions are sensorial phenomena, and like all phenomena of the kind, must be presumed to be seated in essen- tially nervous organs. Again;—when an injury befalls the brain, and the intellectual faculties are perverted or suspended by it, the same thing happens to the affective faculties; and if the viscera fulfil the high office assigned to them, why are not the passions manifested from early infancy, a period when the viscera are in existence and active ? The argument of Bichat, that the phenomena which attend and follow the passions, are referable to the nutritive organs, is not absolute. The functions of animal life are frequently disturbed by the passions, as well as those of organic life. It is not uncommon for them to induce convulsions, mania, epilepsy, and other affections of the ence- phalon. The effect here, as M. Adelon remarks, is mistaken for the cause. The heart certainly beats more forcibly in anger, but the legs fail us in fear; and if we refer anger to the heart, we must, by parity of reasoning, refer fear to the legs. By reasoning of this kind, the pas- sions might be referred to the whole system, as there is no part which does not suffer more or less during their violence. The error arises from our being impressed with the most prominent effect of the pas- sion—the feeling accompanying it—and this is the cause of the gesture and the descriptive language, to which Bichat has given unnecessary weight in his argument. If, then, the views of Bichat regarding the seat of the passions be unfounded, the mischievous doctrine deduced from them—that they are irresistible, and cannot be modified by edu- cation—falls to the ground. His notion was, that the nutritive organs are the source of irritative irradiations, which compel the brain to form the determinations that constitute the passion, and to command the movements by which it is appeased or satisfied. A similar view is embraced by M. Broussais,3 who, however, conceives, that the pas- sions can be fomented and increased by attention, until they become predominant. Daily experience, indeed, exhibits the powerful effect produced on the passions by well-directed moral restraint. How many gratifying instances have we of persons, whose habitual indulgence of the lowest passions and propensities had rendered them outcasts from society, having become restored to their proper place by exerting due control over their vicious inclinations and habits! We can not°only curb the expression of the passions, as we are constantly compelled to 1 Op. citat., i. 94. 2 Art. Enceph. (Physiol.) in Diet, de Me"d., vii. 521, and Physiologie de l'Homme, edit, cit., i. 510. 3 Examen des Doctrines M6dicales, ii. 388, and Physiology applied to Pathology Drs. Bell and La Roche's translation, p. 136, Philadelphia, 1832. ' SOURCES OF THE INTELLECTUAL SPHERE. 157 do in social intercourse; but even modify the internal susceptibility by well-directed habits of repression. Lastly. Many physiologists have considered the brain as a great nervous centre for the reception and elaboration of different impressions conveyed thither by the external senses; and absolutely requiring such impressions for the mental manifestations. They consequently rank, amongst the conditions necessary for such manifestations, not only the brain which elaborates them, but the parts that convey to it the impres- sions or materials on which it has to act; and conceive, that a necessary connexion exists between these two orders of parts. The supporters of these opinions ascribe the differences observed in the intellectual and moral faculties of different persons as much to diversity in the number and character of the impressions as to differences in the encephalon itself. They do not all, however, agree as to the source of the impres- sions, which they conceive to be the raw material for the intellectual and moral acts. M. Condillac1 and his school admit only one kind; —those proceeding from the external senses, which they term external impressions. M. Cabanis,2 in addition to these, admits others proceed- ing from every organ in the body, which he terms internal impressions. The school of Condillac set out with the maxim ascribed to Aristotle, "nihil est in intellectu quod non prius fuerit in sensu ;" and they adopt, as an elucidation of their doctrine, the ingenious idea of Condillac—of a statue, devoid of all sensation, which is made to receive each of the five senses in succession; and which, he attempts to show, from the impressions received, may be able to develope gradually the different intellectual and moral faculties. All these, he affirms, are derived from impressions made on the external senses; and he considers the whole of human consciousness to be sensation variously transformed. The views of Condillac have been largely embraced, with more or less modification; and, at the present day, many metaphysicians believe, that impressions on the senses are the necessary and exclusive materials for all intellectual acts. His case of the statue seems, how- ever, to be by no means conclusive. It must, of course, be possessed of a centre for the reception of impressions made upon different senses, otherwise no perception could occur; and if we can suppose it possible for such a monstrous formation as a being totally devoid of external senses to exist; such a being must not only be defective in the nerves which, in the perfect animal, are destined to convey impressions to the brain, but probably in the cerebral or percipient part likewise. From defective cerebral conformation, therefore, the different mental pheno- mena might not be elicited.3 If, however, we admit in such a case the possible existence of cerebral structure,—particularly of those portions that are especially concerned in the function of thought,—being pro- perly organized, it appears to us, that certain mental or moral manifesta- tions ought to exist. Of course, all knowledge of the universe would be precluded, because deprived of the instruments for obtaining such know- ledge ; but the brain would act as regarded the internal sensations. In order that such a being may live, he must be supplied with the neces- 1 Traite des Sensations, i. 119. 2 Rapport du Physique et du Moral de l'Homme, 4eme edit., par G. Pariset, Paris, 1824. s Adelon, op. citat., i. 519. 158 SENSIBILITY. sary nourishment; possess all those internal sensations or wants that are inseparably allied to organization; and must, consequently, feel the desires of hunger and thirst; but we have seen, that these sensa- tions require the intervention of the brain as much as the external sensations. Supposing him, again, to survive the period of puberty, he must experience the instinctive changes, which occur at this period, and which must furnish impressions to the encephalon. In this assumed case, then, a certain degree of mental action might exist; and, under the supposition of a properly organized brain, ideas—limited, it is true, in consequence of the privation of the ordinary inlets of knowledge— might be formed; and memory, imagination, and judgment be com- patible within certain limits. The objections to the view, that the intellectual and moral sphere of man and animals is proportionate to the number and perfection of the external senses are overwhelming. Animals have the same number of senses as man, and, frequently, have them more perfect; yet in none is the mental sphere co-extensive. The idiot has the external senses as delicate as the man of genius, and often much more so; many of those of the greatest talents having the senses extremely obtuse. It has been already remarked, that the superiority of the human intellect has been referred entirely to the sense of touch, and to the happy organization of the human hand; but the case of Miss Biffin, and others, and that of the young artist cited by M. Magendie,1 negative this pre- sumption. The senses are important secondary instruments,—indis- pensable for accomplishing certain manifestations of the mind, but, in no way, determining its power. The example of the deaf and dumb is illustrative of this matter.2 If a child be born deaf, he is necessarily dumb; inasmuch as he is unable to hear those sounds which, by their combination, constitute language; and cannot therefore imitate them;—a connexion between the functions of hearing and speech, which was not well known to the ancients. For a length of time, these objects of compassionate interest were esteemed to be beyond the powers of any kind of intellectual culture, and were permitted to remain in a state of the most profound ignorance. The ingenuity of the scientific philanthropist has, however, devised modes of instruction, by which their mental power has been exhibited in the most gratifying manner, and in a way to prove, that the sense of hear- ing is not indispensable for great mental developement; but that its place may be supplied, to a great extent, by the proper exercise of others. The deaf and dumb, deprived of the advantages of spoken language, are compelled to have recourse to the only kind available to them,—that addressed to the eye. In this typical way, by a well-devised system of instruction they can be taught to preserve their ideas, and to multiply them, like the perfectly formed, by the spoken and written language,— without one or the other of which the human mind would have remained in perpetual infancy. Thus, the deaf and dumb have not only like ideas; but the same words to convey them to others. Yet the deaf and dumb are not so much the objects of our commise- ration as they who have been deprived, from birth or from early in- 1 See vol. i. p. 695. 2 Gall, op. cit., i. 119. MENTAL SPHERE OF THE DEAF, DUMB, AND BLIND. 159 fancy, of both sight and hearing, and have thus been devoid of two of the most important inlets for the entrance of impressions from the sur- rounding world. In such case, it is obvious, they are shut out from all instruction, except what can be afforded by the senses of touch, smell, and taste; yet even here we have the strongest evidence of independent intellect. One of the most striking cases of the kind is that of the Scotch boy Mitchell, the object of much interest to Spurzheim and to Dugald Stewart,1 both of whom have described his case in their writings. It is matter of uncertainty, whether either his deafness or blindness was total. The evidences of the sensation of hearing were, in a high degree, vague and unsatisfactory; but he gave more con- vincing proofs of the possession of partial vision. He could, for exam- ple, distinguish day from night; and, when quite young, amused him- self by looking at the sun through crevices in the door, and by kindling a fire. At the age of twelve, the tympanum of each ear was perfo- rated ; but without any advantage. In his fourteenth year, the opera- tion for cataract was performed on the right eye, after which he recog- nized more readily the presence of external objects; but never made use of sight to become acquainted with the qualities of bodies. Before and after this period, red, white, and yellow particularly attracted his attention. The senses, by which he judged of external bodies, were those of touch and smell. His desire to become acquainted with objects was great. He examined every thing he met with, and each action indicated reflection. In his infancy, he smelt at every one who ap- proached him; and their odour determined his affection or aversion. He always recognized his own clothes by their smell; and refused to wear those which he found to belong to others. Bodily exercises, such as rolling down a small hill, turning topsy-turvy, floating wood or other objects on the river that passed his father's house; gathering round, smooth stones, laying them in a circle, and placing himself in the mid- dle, or building houses with pieces of turf, &c, were a source of amuse- ment to him. After the operation on his right eye, he could better distinguish objects. His countenance was very expressive; and his natural language not that of an idiot, but of an intelligent being. When hungry, he carried his hand to his mouth, and pointed to the cupboard where the provisions were kept; and, when he wished to lie down, re- clined his head on one side upon his hand, as if he wished to lay it upon the pillow. He easily recollected the signification of signs that had been taught him ; all of which were of course of the tactile kind. To make him comprehend the number of daj^s before an event would hap- pen, they bent his head as a sign that he would have to go to bed so many times. Satisfaction was expressed by patting him on the shoulder or arm; and discontent by a sharp blow. He was sensible of the caresses of his parents; and susceptible of different emotions—hatred, passion, malice, and the kindlier feelings. He was fond of dress, and had great fears of death, of the nature of which he had manifestly cor- rect notions. Mitchell's case has been pregnant with interest to the 1 Elements of the Philosophy of the Human Mind, &c. ; Transactions of the Royal Society of Edinburgh, vol. vii. ; and Dr. Gordon, ibid., vol. vi.; also, History of James Mitchell, a boy, born blind and deaf, by James Wardrop, London, 1813. 160 SENSIBILITY. metaphysician; but it is not so elucidative as it would have been had the privation of the senses in question been total. There is, in the American Asylum at Hartford in Connecticut, a being not less deserving of attention than Mitchell.1 Her name is Julia Brace. She is the daughter of John and Rachel Brace, natives of Hartford, and was born in that town in June, 1807 ; so that she is now (1856) forty-nine years old. At four years of age she was seized with typhus fever; was taken sick on the evening of Monday, Novem- ber 29, 1811; and, on the Saturday morning following, became both blind and deaf. Prior to her illness, she had not only learned to speak, but to repeat her letters, and to spell words of two or three syllables; and, for some time after the loss of her sight and hearing, she was fond of taking a book, and spelling words and the names of her acquaint- ances. She retained her speech pretty well for about a year; hut gradually lost it, and appears to be now condemned to perpetual silence. For three years she could still utter a few words, one of the last of which was "mother." At first she was unconscious of her mis- fortune, appearing to think, that a long night had come upon the world; and often said, " It will never be day." She would call upon the family to " light the lamp," and was impatient at their seeming neglect, in not eve*n answering her. At length, in passing a window, she felt the sun shining warmly upon her hand; and pointed with de- light to indicate that she recognized this. From the January after her illness, until the following August, she would sleep during the day, and be awake through the night; and it was not until autumn, by taking great pains to keep her awake during the day, that she was set right. At present, she is as regular in this respect as other persons. From the period of her recovery, she seemed to perceive the return of Sab- bath ; and, on Sunday morning, would get her own clean clothes, and those of the other children. If her mother was reading, she would find a book, and endeavour to do so likewise. The intervention of a day of fasting or thanksgiving confused her reckoning; and some time elapsed before she got right. During the first winter after her recovery, she was irritable almost to madness; would exhibit the most violent passion, and use the most profane language. The next summer she became calmer; and her mother could govern her, to some extent, by shaking her, in sign of disapprobation ; and stroking or patting her head, when she conducted herself well. She is now habitually mild, obedient and affectionate. During the first summer after her illness, she was very unwilling to wear clothes, and would pull them off vio- lently. At length, her mother took one of her frocks and tried it on her sister, with a view of altering it for her. Julia had ever been remarked for her sense of justice in regard to property. This seemed to be awakened; and she took the frock and put it on herself. After this she was willing to wear clothes, and even cried for new ones. She has ever since been fond of dress. At nine years of age she was taught to sew; and, since that time, has learned to knit. She has been a resident for several years in the American Asylum at Hartford; where 1 Twenty-first Report of the Directors of the American Asylum at Hartford, for the Education and Instruction of the Deaf and Dumb, p. 15, Hartford, 1837, et seal MENTAL FACULTIES—LAURA BRIDGMAN. 161 she is supported in part by the voluntary contributions of visitors, and, in part, by her own labours in sewing and knitting. A language of palpable'signs was early established as a means of communication with her friends; and this has been so improved as to be sufficient for all necessary purposes. Her countenance, as she sits at work, exhibts the strongest evidence of an active mind, and a feeling heart; "thoughts and feelings," says a writer who describes her case, "seem to flit across it like the clouds in a summer sky; a shade of pensiveness will be fol- lowed by a cloud of anxiety or gloom; a peaceful look will perhaps succeed; and, not unfrequently, a smile lights up her countenance, which seems to make one forget her misfortunes. But no one has yet penetrated the darkness of her prison house, or been able to find an avenue for intellectual or moral light. Her mind seems, thus far, in- accessible to all but her Maker." She was seen by the Author in the summer of 1855 ; and impressed him as remarkable for the extent of her intellectual sphere under such privations. A still more interesting example is cited by Dr. Abercrombie1 from the Medical Journals of the time. A gentleman in France lost every sense except feeling on one side of his face; yet his family acquired a method of holding communication with him, by tracing characters upon the part which retained its sensation. These cases are not, perhaps, so unfrequent as has been supposed. Dr. Howe, the superintendent of the Perkins Institution and Massachusetts Asylum for the Blind, stated, some years ago, that four cases in New England, besides that of Julia Brace, had come within his own observation. One of these had been, in 1841, upwards of three years under his care; and the results of his diligence and judgment in this instance have furnished more gratifying results to the psychologist and philanthropist than any, perhaps, on record. Laura Bridgman, the subject of the case, was born in December, 1829. At two years of age, her eyes and ears inflamed, suppurated, and their contents were discharged. At the expiration of two more years of suffering, it was discovered, that her sense of smell was almost wholly destroyed; and, consequently, that her taste was much blunted. She had, therefore, but one sense remaining, that of touch, by which she could become acquainted with the external world. Whilst at home, before her reception into the Asylum, she would explore the house; become familiar with the form, density, weight, and temperature of every article she could lay her hands upon; followed her mother; felt her hands and arms, and endeavoured to repeat every thing herself. She even learned to sew a little, and to knit. She exhibited warm affection towards the members of her family; but the means of com- municating with her were limited. When it was desired that she should go to a place, she was pushed; or that she should approach, she was drawn towards the person. Gently patting on the head signified approbation; on the back, disapprobation. She had made, however, a natural language of her own; and had a sign to express her idea of each member of the family,—such as drawing her finger down each 1 Inquiries concerning the Intellectual Powers, &c, Am. edit., p. 56, New York, 1832. VOL. II.—11 162 SENSIBILITY. side of her face, to allude to the whiskers of one; twirling her hand and arm around, in imitation of the spinning-wheel, for another, &c. In October, 1837, she was received into the Institution for the Blind in Boston. The first experiments made with her consisted in taking articles in common use, such as knives, forks, spoons, keys, &c, and pasting labels upon them with their names printed in raised letters. These she felt very carefully; and speedily found, that the crooked lines spoon differed as much from the crooked lines key, as the spoon differed from the key in form. Small detached labels, with the same words printed upon them, were then put into her hands, and she soon observed, that they were similar to the ones pasted on the articles. She showed her perception of this similarity by laying the label key upon the key, and the label spoon upon the spoon. In this manner she pro- ceeded to acquire a knowledge of language; used the manual alphabet of the deaf mutes with great facility and rapidity, and increased her vocabulary so as to comprehend the names of all common objects. She could soon count to high numbers; and add and subtract small ones. But the most gratifying acquirement which she made, and the one which gave her the most delight, was the power of writing a legible hand, and expressing her thoughts upon paper. She writes with a pencil in a grooved line, and makes her letters clear and distinct. The author has a favourable specimen now before him, in a recent well conceived, and well expressed, letter to a friend. She is expert with her needle; knits easily, and can make twine bags and various fancy articles very prettily; is docile; has a quick sense of propriety; dresses herself with great neatness, and is always correct in her deportment. No definite course of instruction could be marked out; for her inquisitiveness was so great, that she was very much disconcerted if any question, which occurred to her, was deferred until the lesson was over. It was deemed best to gratify her, if her inquiry had any bearing on the lesson; and often she led her teacher far away from the objects with which he com- menced. With regard to the sense of touch it is very acute, even for a blind person. It is shown remarkably in the readiness with which she distinguishes persons. There were, a few years ago, forty inmates in the female wing, with all of whom she was acquainted. Whenever she is walking through the passage-way, she perceives by the jar of the floor, or the agitation of the air, that some one is near her, and it is exceedingly difficult to pass her without being recognized. Her arms are stretched out, and the instant she grasps a hand, a sleeve, or even part of the dress, she knows the person, and lets him pass on with some sign of recognition. The details concerning this interesting being, and her gradual pro- gress in moral and intellectual culture, can be learned from the an- nual reports of the Institution-; which Dr. Howe so ably superintends.1 How strongly do these cases demonstrate the independence of the organ of intellect; requiring, indeed, the external senses for its perfect developement, but still capable of manifesting itself without the pre- 1 Annual Reports of the Trustees of the Perkins Institution and Massachusetts Asylum for the Blind to the Corporation, for the years 1837, et seq.x For an account of many interesting cases of the kind, see Dr. Kitto, The Lost Senses. London 1853. MENTAL FACULTIES—VIEWS OF CABANIS, GALL, ETC. 163 sence of many, and probably of any, of them; and how inaptly, although humanely, does the law regard such beings! "A person," says Blackstone,1 "born deaf, dumb, and blind, is looked upon by the law as in the same state with an idiot, he being supposed incapable of any understanding, as wanting all those senses which furnish the human mind with ideas." But if he grow deaf, dumb, and blind, not being born so, he is deemed non compos mentis, and the same rules apply to him as to other persons supposed to be lunatics. With regard to the deaf and dumb, they are properly held to be competent as wit- nesses, provided they evince sufficient understanding,—and to be liable to punishment for a breach of the criminal laws. M. Cabanis2 embraces the views of Condillac regarding the external senses; but thinks, that impressions from these are insufficient to con- stitute the materiel of the mental and moral manifestations. In confir- mation of this opinion, he observes, that the young infant, and animals at the very moment of birth, frequently afford evidences of complicated acts originating in the nervous centres; and yet the external senses can have been but little impressed. How can we, he asks, refer to the operation of the external senses the motions of the foetus in utero, which are perceptible to the mother, for the latter half of utero-gesta- tion; or the act of sucking executed from the first day of existence? Can we refer to this cause the fact of the chick, as soon as it is hatched, pecking the grain that has to nourish it ? or the one, so frequently quoted from Galen, of the young kid, scarcely extruded from the ma- ternal womb, and yet able to select a branch of the cytisus from other vegetables presented to it? Man and animals, continues M. Cabanis, during the course of their existence, experience mental changes as remarkable as they are frequent; yet nothing in the condition of the senses can account for such difference. For example, at the period of puberty, a new appetite is added; and this, even, when the being is kept in a complete state of isolation. This, he argues, it is impossible to refer to any change in the external senses; which, if they furnished the materials at all, must have been doing so from early infancy; and he concludes, that the difference observable in the mental manifesta- tions, according to sex, temperament, climate, state of health or disease, regimen, &c, cannot be referable to the senses, as they remain the same; and, consequently, we must look elsewhere for the causes of such difference. These M. Cabanis conceives to be the movements by which the organs of internal life execute their functions. Such move- ments, he says, although deep-seated and imperceptible, are transmitted to the brain, and furnish that organ with a fresh set of materials. At puberty, when the testicles become developed, and their function is established by the secretion of sperm, the organic movements during the secretion are the materials of the new desires, which appear at that age. These impressions he calls internal, in contradistinction to the external, or those furnished by the five senses; and he considers, that whilst the external senses serve as the basis for all that we include under the term intellect, the internal impressions are the materials of 1 Commentaries on the Laws of England, i. 304. 2 Rapport du Physique et du Moral, edit. cit. 164 SENSIBILITY. what are called instincts; and, as the organs of internal life, whence the internal impressions proceed, vary more than the senses, according to age, sex, temperament, climate, regimen, &c, it is more easy to find in them organic modifications, which coincide with those exhibited by the mind under those various circumstances. In proof of these opinions, he adduces, besides others, the following specious affirmations. First. As the venereal appetite appears in man and animals synchronously with the developement of the testicles, and is never exhibited when they are removed in infancy, we have reason to believe, that the impressions, which constitute the materials for this new catenation of ideas, must proceed from the testicles. Secondly. Numerous facts demonstrate, that the condition of the uterus has much influence on the mental and moral manifestations of the female. The period of the developement of that organ, for example, is the one at which new feelings arise, and all those manifestations assume more activity; and there is generally a ratio between their activity and that of the uterus. If the state of the uterus be modified, as it is at the menstrual period, or during pregnancy, or after delivery, the mind is so likewise. All these facts ought to induce a belief, he thinks, that impressions are continually emanating from that organ, which, by their variety, occasion the diversity in the state of mental and moral faculties observed in those different cases. Thirdly. It is impossible in the hypochondriac and melancholic constitutions, to mistake the in- fluence exerted upon the mind by the abdominal organs. According as they execute their functions more or less perfectly, the thinking faculty is more or less brilliant or languid; and the affections more or less vivid and benevolent, or the contrary; hence the expressions melancholy1 and hypochondriasis,2 assigned to the states of mind charac- terizing those constitutions, which denote that the cause must be re- ferred to the abdominal organs. The origin of the alternations of inactivity and energy in the intellect, of benevolent and irascible fits of humour, as well as of insanity, is also referable, he says, to the ab- dominal viscera. Hence—M. Cabanis concludes—it is evident, that the abdominal organs are the source of fortuitous and abnormous im- pressions which excite the brain to irregular acts;—and is it not, he asks, probable, that what takes place in excess, in these morbid move- ments, may happen to a less and more appropriate extent in health; and that thus impressions may emanate in a continuous manner from every organ of the body, which may be indispensable to the produc- tion of the mental and moral acts? M. Cabanis, therefore, considers that the axiom of Aristotle should be extended; and that the statue of Condillac is incomplete, in not having internal organs for the ema- nation of internal impressions, which are the materials of the instincts. In this way he accounts for the instincts, which, by some metaphysi- cians, have been looked upon as judgments, executed in the ordinary manner, but so rapidly, that the process has ceased from habit to be perceptible. Finally, he remarks, there is a ratio between the dura- tion and intensity of the intellectual results and the kind of impres- sions, which have constituted their materials. All the mental and 1 From ^ufXaj, "black," and X'^, "bile." 2 Disease of the hypochondres. MENTAL FACULTIES—VIEWS OF CABANIS, GALL, ETC. 165 moral acts, for instance, that are derived from impressions engendered in the very centre of the nervous system or in the brain,—such as those of the maniac,—are the strongest and most durable. After these come the instincts, of which the internal impressions are the ma- terials: they are powerful and constant;—and* lastly, the intellectual acts, which are more transient, because they emanate from external impressions, themselves fickle, and somewhat superficial. According to the views, then, of M. Cabanis and his followers, amongst the organic conditions of the mental and moral manifestations must be placed, not only those of the encephalon and external senses, but of the different organs of the body, which furnish the various in- ternal impressions. The influence of the external senses on the intel- lectual and moral developement has already been canvassed: we have seen, that they are only secondary instruments for making us ac- quainted with external bodies, and that they in nowise regulate the intellectual and moral sphere. The notion, of internal impressions is ingenious, and has led to important improvements in the mode of in- vestigating the different mental and moral phenomena. It was sug- gested, as has been shown, by M. Cabanis, in consequence of the external senses appearing to him insufficient to explain all the pheno- mena. By MM. Gall, Adelon,1 and others, however, all these cases are considered explicable by the varying condition of the brain itself. In the foetus in utero; in the new-born animal, there are already parts of the brain, they say, sufficiently developed; and, accordingly, we witness the actions to which reference has been mac(e by M. Cabanis; and if the intellectual and moral manifestations vary according to sex, temperament, climate, regimen, state of health, &c, it is because the encephalon is, under these circumstances, in different conditions. The chief facts, on which M. Cabanis rests his doctrine, are,—the coinci- dence between the developement of the testicles and the appearance of the venereal appetite; and the suppression of this appetite after cas- tration. It must be recollected, however, that these are not the only changes, that happen simultaneously at puberty. The voice assumes a very different character; but the change in the voice is not a cere- bral phenomenon. It is dependent upon the developement of its organ, the larynx. Yet castration, -prior to puberty, has a decided effect upon it; preventing it from becoming raucous and unmelodious. All these developements are synchronous; but not directly conse- quent upon each other. The generative function has two organs,— one central, the other external; and it is not surprising, that both should undergo their developement at the same period. On the whole, we are perhaps justified in concluding, that the brain alone is the organ of the intellectual and moral faculties. Yet, as before remarked, there is great force in the facts and arguments brought forward by Dr. Carpenter in favour of the emotional acts being seated in what, he terms, the sensorial ganglia: and that as we descend in the animal scale, the cerebrum or organ of the mental manifestations becomes less and less developed, until we ultimately find an encephalic organization in which a common sensorium for the 1 Physiologie de l'Hommo, 2de 6dit., i. 251. 166 SENSIBILITY. reception of sensation and the origination of motion may alone exist; without any organ for the recording of impressions like the cerebrum in more highly endowed organisms. In such case, the motions may be mere responses to sensations experienced, without the presence of the slightest consciousness on the part of the being, or knowledge of the adaptation of means to ends. Still, it may be a question whether such sensations and responsive motions are not possessed by animals devoid of anything resembling the encephalic sensory ganglia of higher organisms, and which are wholly supplied with nerves of the excito- motory class—as the stomato-gastric. The interesting topic of the various instinctive operations of the frame will be considered in an- other part of this work. We shall there find, that instinct cannot in all cases be defined, in the language of M. Broussais,1 to consist in sen- sations originating in the internal and external sensitive surfaces, which solicit the cerebral centre to acts necessary for the exercise of the functions,—such acts being frequently executed without the parti- cipation of mind, and even in its absence,—inasmuch as it is not con- fined to beings possessed of brain, and exists also in the vegetable. Plaving now decided upon the organ of the mental and moral facul- ties, it would be necessary, according to the system adopted in this work, to describe its anatomy; but this has been done elsewhere. PHYSIOLOGY OF THE INTELLECTUAL AND MORAL FACULTIES. When the organ of the intellect is exposed by accident, and we regard it during the reception of a sensation, the exercise of volition, or during any intellectual or moral operation, the action is found to be too molecular to admit of detection. At times, during violent mental contention, a redness of the surface of the brain has been appa- rent, as if the blood had been forced more violently into the vessels; but no light has been thrown by such examination on the wonderful actions that constitute thought. We ought not, however, to be sur- prised at this, when we reflect, that the most careful examination of a nerve does not convey to us the slightest notion how an impression is received by it from an external body; and how such impression is conveyed to the brain. All that we witness in these cases is the result; and we are, therefore, compelled to study the intellectual and moral acts by themselves, without considering the cerebral movements con- cerned in their production. Such study is the basis of a particular science—metaphysics, ideology, or philosophy. Apart from organization, this subject does not belong to physiology; but as some of the points of classification, &c, are concerned in questions that will properly fall under consideration, it may be well to give a short sketch of the chief objects of metaphysical, inquiry; which are, indeed, intimately con- nected in many of their bearings,—as commonly treated by the meta- physician,—with physiology. M. Broussais has considered, that meta- physics and physiology should be kept distinct; and that all the investigations of the metaphysician should be confined to the ideal. " I wish metaphysicians, since they so style themselves," he remarks, 1 Physiol, appliquee k la Pathologic, ch. vii.; or Drs. Bell and La Roche's transla- tion, Philad., 1832. INTELLECTUAL AND MORAL FACULTIES. 167 somewhat splenetically, " would never treat of physiology; that they would only occupy themselves with ideas as ideas, and not as modifi- cations of our organs; that they would never speak either of the brain, the nerves, the temperaments, or of the influence of climates, of locali- ties, or of regimen; that they would never inquire whether there are innate ideas, or whether they come through the medium of the senses; that they would not undertake to follow their developements according to age or state of health; for I am convinced that they cannot reason justly on these points. Such questions belong to physiologists, who can unite a knowledge of the moral nature with that of the structure of the human body." " It is possible," he adds, " that particular cir- cumstances may oblige them to introduce physiological considerations into their calculations; as when it is necessary to estimate the influ- ence of certain laws or customs in relation to temperature, the nature of the soil, the prevailing diseases, &c, but then they should avail themselves of the experience of physiologists and physicians."1 A more appropriate recommendation would be that the metaphysician should make a point of becoming acquainted with physiological facts and reasoning; and, conversely, that metaphysics should form a part of the study of every pl^siologist. The cerebral manifestations comprise two very different kinds of acts;—the intellectual and the moral; the former being the source of all the knowledge we possess regarding ourselves and the bodies sur- rounding us; the latter comprising our internal feelings, appetites, desires, and affections, by which we are incited to establish a relation with the beings around us:—the two sets of acts respectively embracing the qualities of the mind, and those of the heart.2 If we attend to the different modes in which the intellectual mani- festations are evinced in our own persons, we find, that there are several acts which are by no means identical. AYe are conscious of the differ- ence between appreciating an impression made upon one of the exter- nal senses, which constitutes perception, and the recalling of such impres- sion to the mind, which is the act of memory; as well as the distinction between feeling the relations that connect one thing with another, constituting judgment; and the tendency to act in any direction, which we call will. The consciousness of these various mental processes has induced philosophers to admit the plurality of the intellectual acts, and to endeavour to reduce them all to certain primary faculties; in other words, to faculties which are fundamental or elementary, and by their combination give rise to other and more complex manifestations. To this analytical method they have been led by the fact, that the different acts, which they esteem elementary, exhibit great variety in their degrees of activity: one, for example, may be impressed with a cha- racter of energy—as the memory;—whilst another, as the judgment, may be singularly feeble;—and conversely. M. Broussais conceives, that without the memory we cannot exercise a single act of judgment; as it is always necessary, in order to judge, that we should experience 1 De l'lrritation et de la Folie, Paris, 1828; or Dr. Cooper's translation, Columbia, S. C, 1831. » Adelon, Facult's de l'Esprit et de l'Ame, in Diet, de M,d., viii. 469, Paris, 1823; and Physiologie de l'Homme, edit, cit., i. 527. 168 SENSIBILITY. two successive perceptions, which we could not do, unless possessed of the faculty of renewing that which we had felt before; in other words, unless we possessed memory. Hence the loss of this faculty, he says, necessarily occasions that of judgment, and reduces man to a state of imbecility. To a certain extent this is true. Total privation of memory must be attended with the results described. If an indi- vidual retains no consciousness of that which impressed him pre- viously, there can obviously be no comparison. A man may, however, have an unusual memory for certain things and not for others; he may astonish us by the extreme accuracy of his recollection of numbers, places, or persons; and yet he may be singularly deficient in judging of other matters;—his memory suggesting only one train of objects for comparison. In enumerating the faculties, which, by their union, constitute the intellect, we observe great discrepancy amongst metaphysicians. Some admit will, imagination, understanding, and sensibility; others, sensi- bility, imagination, memory, and reason; others will, intelligence, and memory; and others, again, imagination, reflection, and memory. The views of M. Condillac1 on this subject have perhaps excited more atten- tion than those of any other individual. Professing, as we have seen, that all our ideas are derived from successive operations of the senses and the mind, he admits the following constituent faculties of the intellect:—sensation, attention, comparison, judgment, reflection, imagin- ation, and reason. Sensation he defines to be—the faculty of the mind, which affords the perception of any sensitive impression. Attention, the faculty of sensation, applied exclusively to a determinate object; being, as the word imports, the tension of the mind upon a particular object. Comparison, the faculty of sensation, applied to two objects at once. Judgment, the faculty by which the mind perceives the con- nexions, that exist between the objects compared. Reason, the faculty of running through a succession of judgments, which are connected with, and deduced from, each other. Reflection, as the word indicates, the faculty by which the mind returns upon itself, upon its own pro- ducts, to prove their correctness, and to subject them again to its power; and imagination, to which Condillac attaches memory,—the faculty possessed by the mind of reproducing at will the different im- pressions, and all the products of its own operations. With regard to the order of catenation of these different faculties, he considers sensation to be first put in play; and if, amongst the perceptions, there is one, of which we have a more lively consciousness, and which attracts the mind to it alone, it is the product of attention: then comes comparison, which is nothing more than double attention : comparison is irresisti- bly succeeded by judgment: if, from one judgment, we pass to another deduced from it, we reason: if the mind turns back on its own produc- tion, we reflect: and lastly, if the mind spontaneously awakens its dif- ferent perceptions imagination is in action. All these faculties are thus made to be deduced from each other; to originate in the first or sen- sation ; and all are sensation successively transformed. The doctrine of M. Condillac, abstractly considered, has already en- gaged attention. The division of the faculties, which he conceives, by 1 Op. citat. FACULTIES THAT CONSTITUTE THE INTELLECT. 169 their aggregation, to form the intellect, is simple and ingenious, and appears to be more easily referable to physiological principles than that of other metaphysicians; accordingly, it has been embraced, with more or less modification, by certain physiological writers. The power of reflection, according to M. Broussais, is the character- istic of the human intellect; and to reflect is to feel. Man not only feels the stimulation produced by external agents, and by the movements of his own organs, which constitutes sensation or perception, but he is con- scious that he has felt these stimulations: in other words, he feels that he has felt; he has, consequently, a perception of his actual perception, which, M. Broussais says, constitutes mental reflection. This process he can repeat as often as he thinks fit, and can observe all his sensations, and the different modes in which he felt, whilst occupied with his feel- ings. From this study he derives an idea of his own existence. "He distinguishes himself," to quote the dry description of M. Broussais, "in the midst of creation, and paying regard only to his own existence, compared with all that is not himself, he pronounces the word I (moi), and says, I am; and viewing himself in action, says, I act, I do, &c. Perception of himself and of other bodies procures him what are de- nominated ideas. This is, therefore, another result of reflection; in other words, of the faculty he possesses of feeling himself feel. But man feels, besides, that he has already felt: this constitutes memory. In comparing two perceptions with each other, which are felt in succession, a third perception results, which is judgment. Consequently, to judge is only to feel." "Hence," he concludes, "sensation, reflection, and judg- ment are absolutely synonymous, and present to the physiologist nothing more than the same phenomenon. The will or the faculty by virtue of which man manifests his liberty by choosing, among different per- ceptions, the one he must obey;—the faculty, which gives him the power of resisting, to a certain extent, the suggestions of instinct—is founded on reflection. Consequently, when we consider it in a physio- logical point of view, we can only discover in it the faculty of feeling ourselves, and of perceiving that we feel ourselves." Some of the later French metaphysicians have proposed certain modifications of the system of Condillac. M. De La Romiguiere,1 for instance, denies that sensation is the original faculty, and derives all from attention. The mind, he remarks, is passive during the reception of sensation, and does not commence action until directed to some object, or until it attends. According to him, the intellect consists of three faculties—attention; comparison or double attention; and reason or double comparison. Judgment, imagination, and memory are not primary faculties: judgment is the irresistible product of comparison; memory is but the trace, which every perception necessarily leaves behind it; and imagination is but a dependence on reason. M. Des- tutt-Tracy,2 again, reduces the number of primary faculties to four— perception, memory, judgment, and will or desire. According to him, attention is not an elementary faculty. It is but the active exercise of the intellectual faculties. The same applies to reflection and reason, which are only a judiciously combined employment of those faculties; and 1 Lecons de Philosophie, torn. i. 4eme lecon. 2 Llemens d'LLologie, 2de edit., Paris, 1804. 170 SENSIBILITY. to comparison and imagination, both of which enter into the judgment. This division is embraced by M. Magendie.1 Mr. Dugald Stewart's3 classification is into, 1, Intellectual powers, and, 2, Active and moral pow- ers; including, in the former, percepdion, attention, conception, abstraction, the associating principle, memory, imagination, and reason. Dr. Brown3 reduces all the intellectual states to simple suggestion and relative sug- gestion,—comprising, in the former, conception, memory, and imagination, —in the latter, judgment, reason, abstraction, and taste. Dr. Abercrombie4 considers the mental operations to be chiefly referable to four heads,— memory, abstraction, imagination, and reason or judgment; whilst Kant has twenty-five primary faculties or forms; pure conceptions or ideas d priori. These are a few only of the discrepant divisions of psychologists. The list might have been extended by the classifications of Aristotle, Bacon, Hobbes, Locke, Bonnet, Hume, Yauvenargues, Diderot, Reid, and others. Perhaps the most prevalent opinion at present is, that the original faculties are—perception, memory, judgment, and imagination. It is impossible, were it even our province, to reconcile these discre- pancies. They are too considerable to hope, that this will ever be effected by metaphysical inquiry. We must, therefore, look to physio- logical investigation, if not with well-founded—with the only—hopes, we can entertain, for the elucidation of the subject; and we shall find presently, that the minds of metaphysical physiologists have been turned in this direction, and that many interesting facts and speculations have been the result. A second topic of metaphysical inquiry regards the formation of the intellectual notions. On this, there have been two principal opinions; some, as Plato, Des Cartes, the Kantists, Kanto-Platonists, &c, believing in the existence of innate ideas;—others, as Bacon, Locke, and Condillac, denying—as we have seen—the existence of such innate ideas, and asserting that the human intellect, at birth, is a tabula rasa; and that the mind has to acquire and form all the ideas it possesses from im- pressions made on the senses. The truth includes probably both these propositions,—the action of the senses and intellectual faculties being alike necessary;—the former receiving the external and internal im- pressions, and transmitting them to the mind, which, through the cerebral organ, produces the latter. Under the terms affective faculties, affections, and passions, are compre- hended all those active and moral powers, which connect us with the beings that surround us, and are the incentives to our social and moral conduct. To this class belong,—the feeling, which attaches the parent to the child; that which attracts the sexes; and compassion, by which we are led to assist a suffering fellow-creature. They are, in truth, in- ternal sensations, but of a higher cast than those of hunger and thirst;— the latter being purely physical, and announcing physical necessities; the former suggesting social and moral relations. Such affective facul- ties are the foundation of what are called moral wants; and, like the 1 Precis Eleraentaire, i. 196. 2 Elements of the Philosophy of the Human Mind, 3d edit., Lond., 1808 ; and Amer. edit., Brattleborough, Vt., 1813. 3 Lectures on the Philosophy of the Human Mind, Amer. edit., Boston, 1826. « Inquiries concerning the Intellectual Powers, Amer. edit., p. 91, New'York,'1832. AFFECTIVE FACULTIES. 171 internal sensations in general, are the source of pleasure, when satis- fied,—of pain, when resisted; and it is only when they are extreme and opposed, that they acquire the name of passions} The analysis of these is attended with the same difficulties as that of the intellectual faculties. Their plurality is universally admitted, but still greater discrepancy exists as to their precise number and connexion.2 Many moralists have united the moral faculties under the head of will or desires. Condillac3 is one of those. Every sensation, he observes, has the character of pleasure or pain, none being indifferent; as soon, there- fore, as a sensation is experienced, the mind is excited to act. This tendency is at first but slightly marked, and is only an uneasiness {malaise)-, but it soon increases and becomes restlessness or inquietude;— in other words, a difficulty experienced by the mind of remaining in the same situation. This gradually becomes desire, torment, passion, and finally will excited to the execution of some act. Some have endea- voured, by ultimate analysis, to derive all the affective faculties from one principal faculty—that of self-love,—the inward feeling which in- duces all to attend to themselves, their own preservation, and welfare. All the faculties, they assert, are returns of this self-love upon itself; and, as in the case of the intellectual faculties, attempts have been made to classify them; but scarcely two metaphysicians agree. Some have divided them into the agreeable and distressing; others into those of love and hatred; many—regarding their effects upon society—into the vir- tuous, vicious, and mixed;—the first comprising those that are useful to society,—as, filial, parental, and conjugal love, which form the foundation of families; goodness, pity, and generosity, which, by inducing men to assist each other, facilitate the social condition; and the love of labour, lwnour, and justice, which have the same result, by constituting so many social guarantees. The vicious passions, on the contrary, are such as injure man individually, and society in general, as pride, anger, hatred, and malice. Lastly, the mixed passions are such as are useful or in- jurious, according to their use or abuse; as ambition, which may be a laudable emulation, or an insatiable passion, according to its extent and direction. Again, the passions have been divided into the animal or such as belong to physical man, and the social or such as appertain to man in society. The first are guides for his preservation as well as for that of the species. To them belong fear, anger, sadness, hatred, excessive hunger, the venereal desire when vehement, jealousy, &c. In the second are included all the social wants when inordinately experienced. These vary according to the state of civilization of the individual and the community. Ambition, for instance, it is said, may be regarded, Avhen inordinate, as excessive love of power:—avarice, as an exaggeration of the desire for fortune:—hatred, and vengeance, as the natural and impetuous -desire of injuring those that injure us, &c. Mr. Dugald Stewart's4 division of the active and moral powers embraces, 1. Instinctive principles, and 2. Rational principles,—the former including appetites, desires, and affections; the latter self-love and the moral faculty; ail of 1 From patior, I suffer. 2 Adelon, art. Affection, Dictionnaire de Medecine, lere edit.; and Physiologie da l'Homme, edit, cit., i. 537. 3 Op. citat. * Op. oitat. 172 SENSIBILITY. which Dr. Brown1 comprises under emotions, immediate, retrospective, or prospective;—and lastly, Dr. Abercrombie2 refers all the principles, which constitute the moral feelings, to the following heads: 1. The desires, the affections, and self-love; 2. The will; 3. The moral principle, and 4. The moral relation of man towards the Deity. It is obvious, that the analysis of the moral faculties has been still less satisfactorily executed than that of the intellectual; and that little or no attempt has been made to distinguish those that are primary or fundamental from those that are more complex; consequently, the remarks which were made regarding the only quarter we have to look to, for any improvement in our knowledge of the intellectual acts, apply d fortiori to the moral; although it must be admitted, that the difficulties attendant upon the investigation of the latter are so great as to appear to be almost insuperable. As the brain, then, is admitted to be the organ of the intellectual and moral faculties, it is fair to presume that its structure may be found to vary according to the number and character of those; and if there be primary or fundamental faculties, each may be conceived to have a spe- cial organ concerned in its production, as each of the external senses has its organ. According to this view, the cerebral organization of animals ought to differ according to their psychology: where one is simple, the other should be so likewise. This seems, so far as we can observe, to be essentially the fact. "In the series of animals," says M. Adelon,3 "we observe the brain more complicated as the mental sphare is more extensive; and in this double respect a scale of gradation may be formed from the lowest animals to man. If he has the most ex- tensive moral sphere, if he alone has elevated notions of religion and moralit}'-, he also has the largest brain, and one composed of more parts; so that if the physiology of the brain were more advanced, we might be able, by comparing the brains of animals with his, to detect the material condition, which constitutes humanity. If the brain were not constructed d priori for a certain psychology, as the digestive apparatus is for a certain alimentation; and if the mental and moral faculties were not as much innate as the other faculties, there would be nothing abso- lute in legislation or morals. The brain and its faculties are, however, in each animal species, in a ratio with the role, which such species is called upon to play in the universe. If man is, in this respect, in the first rank; if he converts into the delicate affections of father, son, hus- band, and country, those brute instincts by which the animal is attached to its young, its female, or kennel; if, in short, he possesses faculties which animals do not,—religious and moral feelings, with all those that constitute humanity,—it is owing to his having a more elevated voca- tion ; to his being not only king of the universe, but destined for a future existence, and specially intended to live in society.- Hence it was necessary, that he should not only have an intellect sufficiently extensive to make all nature more or less subject to him, but also a psychology such, that he might establish social relations with his fel- 1 Op. citat. . * Philosophy of the Moral Feelings, Amer. edit., p. 35, New York, 1833. 3 Art. Encephale, in Diet, de Med., vii. 52J; and Physiologie de l'Homme, edit. cit., i. 524. MENTAL FACULTIES—SIZE OF THE BRAIN. 173 lows. It was^ necessary, that he should have notions of the just and the unjust, and be able to elevate himself to the knowledge of God;— to those sublime feelings, which cause him so to regulate his conduct as to maintain with facility his mortal connexions, and deserve the future life to which he is called." But if the intellectual sphere be regulated by the cerebral develope- ment, can we not, it has been asked, estimate the connexion between them? And if there be different primary cerebral faculties, each of which must have an organ concerned in its production, can we not point out such organ in the brain? Several investigations of this character have been attempted, with more or less success: generally, however, they have added but little to our positive knowledge, and this, principally, from the intricacy of the subject. Until of late years, attention was chiefly paid to the mass and size of the encephalon; and it was, at one time, asserted that the larger it is, in any species or in- dividual, the greater the intellect. Man, however, has not absolutely the largest encephalon, although he is unquestionably the most intel- ligent of beings. The weight of the encephalon of a child six years of age is given by Haller at two pounds three ounces and a half; whilst that of the adult is estimated by Sommering at from two pounds three ounces, to three pounds three ounces and three-quarters;1 by Tiede- mann2 at from three pounds three ounces, to four pounds eleven ounces troy,—the brain of the female weighing, on an average, from four to eight ounces less than that of the male. The average weight, after the meninges have been stripped off, is, in the healthy adult male, according to M. Lelut,3 about 1346 grammes or three pounds and a half avoirdupois; of which the cerebrum weighs 1170, the cerebellum 176 grammes. In the female, the weight of the encephalon was about TLth less. From the tables of weights of the brain given by Dr. Sims, Clendinning,4 Tiedemann, and Dr. John Reid,5 it was found that in a series of 278 cases the maximum weight of the adult male brain was 65 ounces: the minimum weight 34 oz. In a series of 191 cases, the maximum weight of the brain of the adult female was 56 oz.:—the minimum weight 31 oz. By taking the mean of all the cases, an ave- rage weight was deduced of 49\ oz. for the male; and of 44 oz. for the female brain; and although many female brains exceed in weight par- ticular male brains, it is found that the adult male encephalon is heavier than that of the female, by from five to six ounces on an average.6 The encephalon of the elephant, according to Haller, weighs from seven to ten pounds. The brain of an African elephant, seventeen years old, was found by Perrault to weigh nine pounds; that of an Asiatic elephant, weighed by A. Moulins, was ten pounds. Sir Astley 1 Weber's Hildebrandt's Handbucb. der Anatomie, Band iii. 423; Rudolphi, Grun- driss, u. s. w. ii. 11, Berlin, 1823. 2 Proceedings of the Royal Society for 1836; also Das Hirn des Negers mit des Eu- ropiiers und Orang-outangs vergleichen, Heidelb., 1837, cited in Brit, and For. Med. Rev., for Oct., 1839, p. 374. 3 Gazette Medicale; and Medico-Chirurgical Review for Oct., 1837, p. 507. 4 Medico-Chirurgical Transactions, xix. 353. 5 Lond. and Edinb. Monthly Journal of Medical Science, April, 1843, p. 298. 6 Quain's Human Anatomy, by Quain and Sharpey, Amer. edit, by Leidy, ii. 185, Philad., 1849. 174 SENSIBILITY. Cooper dissected one that weighed eight pounds one ounce and two grains, avoirdupois.1 These facts, consequently, overthrow the proposition; and, more- over, in certain insects, the bee and the ant, we meet with evidences of singular intelligence. The proposition was therefore modified, and it was laid down, that the larger the encephalon, compared with the rest of the body, the greater the mental sphere. When the subject was first investigated in this way, the result, in the case of the more common and domestic animals, was considered so satisfactory, that without farther comparison the proposition was considered established. More modern researches have shown, that it admits of numerous ex- ceptions; and that several of the mammalia, and many diminutive and insignificant animals have the advantage over man in this respect. It has, indeed, been properly observed by Mr. Lawrence,2 that it can- not be a very satisfactory mode of proceeding, to compare the body, of which the weight' varies so considerably, according to illness, emaciation, or embonpoint, with the brain, which is affected by none of those circumstances, and appears to remain constantly the same. This is the cause why, in the cat, the weight of the encephalon com- pared with that of the body has been stated as 1 to 156 by one com- parative anatomist; and as 1 to 82 by another; that of the dog as 1 to 305 by one, and as 1 to 47 by another, &c. The following table/taken chiefly from Haller3 and Cuvier,4 exhibits the proportion borne by'the encephalon to the rest of the body in man and certain animals. Child, 6 years old Adult . Gibbon . Sapajous, from Apes Baboons Lemurs . Bat (vespertilio) Mole . Bear Hedgehog Fox' Wolf . Beaver . Hare Rabbit . Rat Mouse . Wild Boar . Domestic do. JL tt t0 Z? --JJ t0 8-B & to ^ T&8 z£j zsa Zilff T ZZ8 to Tiz to it* Elephant Stag Roebuck (young) Sheep Ox Calf Horse . Ass Dolphin Eagle Goose Cock . Canary Bird . Humming Bird5 Turtle . Tortoise Frog Shark . Pike Carp A, • ZSff • ih j£t tO T^z rio to 5i5 • zls 7J5 to 5^5 ; lh 35> B5> T5Z • zsu • 3BU • zS • h ■ TT ■ 5B'S8 • I&S • ITS • Z4"55 • 1^6* • sh In 9 males, between 27 and 50 years of age, who died immediately, or within a few hours after accidents, and other external causes of death, and who had been previously in good health, Dr. John Reid6 obtained the following results;—the weight used being avoirdupois:— 1 Dr. Todd, art. Nervous Centres, in Cyclop, of Anat. and Physiol., Pt xxv d 664 Lond., 1844. • y » 2 Lectures on Physiology, Zoology, &c, p. 191, Lond., 1819. 3 Element. Physiol., x. sect. 1. * Lecons d'Anat. Comp. ix art 5 5 On the authority of ex-President Madison. P ' 6 Lond. and Edinb. Monthly Journal of Med. Science, April, 1843, p. ?22. MENTAL FACULTIES—SIZE OF THE BRAIN. 175 134 lbs .3} r OZ. 3 lbs .4 oz. 4* dr. 5 oz. 7* dr. 6 oz. 6 dr. 6 oz. 7* dr. 12 oz. 6 dr. t , as 1 to 40i as 1 to 1734, ■ as 1 to 9f Average weight of body (9 weighed)..... Average of encephalon (6 weighed)..... Average of cerebellum (4 weighed)..... Average of cerebellum with pons and medulla (5 weighed) Or, taking the average of the four cases only in which the cerebellum was taken....... Average of heart (9 weighed)..... Relative weight of body to encephalon (6 weighed) Relative weight of body to heart (9 weighed) . Relative weight of encephalon to cerebellum (4 weighed) Relative weight of encephalon to cerebellum, with pons and me- dulla (5 weighed).........as 1 to 8/g M. Bourgery1 found, that the mean weight of the encephalon being 20393*5 grains troy, the cerebral hemispheres weigh 16940*46 grains; the cerebellum, 2176*7 grains; the cephalic prolongation of the cere- bro-spinal axis, 1312*2 grains; of which the optic thalami and corpora striata make 879*9 grains; the medulla oblongata with the pons Varolii 432*2 grains; and the spinal cord 710*1 grains. Hence, in man, the cerebral hemispheres include a nervous mass, which is four times greater than the rest of the cerebro-spinal mass ; nine times greater than the cerebellum; thirteen times greater than the cephalic stem of the spinal cord; and twenty-four times greater than the spinal cord itself. It has been the general belief, that the brain of the negro is inferior to that of the white variety of the species; but certain observations of M. Tiedemann led him to the belief, that there is no perceptible differ- ence either in its average weight or average size in the two varieties, and that the nerves compared with the size of the brain are not larger in the former than in the latter. In the external form of the brain of the negro a very slight difference only could be traced; and he affirmed further, that there is absolutely no difference in its external structure, nor does the negro brain exhibit any greater resemblance to that of the ourang outang than the brain of the European, excepting, perhaps, in the more symmetrical disposition of its convolutions. Tiedemann's observations were made, however, upon few subjects; and his own facts do not bear out all his deductions. He admits, that the anterior part of the hemispheres was something narrower than is usually the case in Europeans, "which,"—says Dr. Combe,2—"as the anterior portion is the seat of intellect, is really equivalent to conceding that the negro is natu- rally inferior in intellectual capacity to the European." M. Tiedemann established that the average capacity of the Ethiopian skull is somewhat less than that of the European, and that a large sized skull is considera- bly less frequent among them than among any other races of mankind.3 The following table, drawn up by Dr. Morton,4 exhibits the absolute capacity of the cranium or bulk of the encephalon in cubic inches, ob- tained by filling the cavity of the crania with leaden shot, one-eighth of an inch in diameter, in different races and families of man.5 It suf- ficiently exhibits how little can be judged, in this manner, of their rela- tive intellectual aptitudes. 1 Lond. Med. Gaz., Jan., 1845, p. 462. 2 Phrenological Journal, No. liv., Dec, 1837. 3 Brit, and For. Med. Rev., for Oct., 1839, p. 379. 4 Catalogue of Skulls, of Man and the Inferior Animals in the collection of Samuel George Morton, M. D., &c, 3d edit., p. viii., Philad., 1849. * For the ingenious process invented by Mr. J. S. Phillips, of Philadelphia, by which these measurements were taken, see Dr. Morton's Crania Americana, p. 253, Philad. and Loud., 1839. 176 SENSIBILITY. TABLE, Showing the Size of the Encephalon in cubic inches, as obtained from the measure- ments of 023 Crania of various Races and Families of Man. (N. B.—I. C means Internal Capacity.) RACES AND FAMILIES. No. of Skulls. Largest. I. c. Smallest. I. C. Mean. Mean. MODERN CAUCASIAN GROUP. Teutonic Family. Germans, 18 114 70 90 1 English, 5 105 91 96 [ 92 Anglo-Americans, 7 97 82 90 J Pelasgic Family. ] Persians, 10 94 75 84 Armenians, 1 J Circassians, Celtic Family. Native Irish, } 6 97 78 87 Indostanic Family. Bengalees, &c.t 1 32 91 67 80 Semitic Family. Arabs, } 3 98 84 89 Nilotic Family. Fellahs, }» 96 66 80 ANCIENT CAUCASIAN GROUP. From the Catacombs. Pelasgic Family. Gr&co-Egyptians, }u 97 74 88 Nilotic Family. L Egyptians, J 55 96 68 80 MONGOLIAN GROUP. Chinese Family, 6 91 70 82 MAL AT GROUP. Malayan Family, 20 97 68 86 J 85 Polynesian Family, 3 84 82 83 AME RICAN GROUP. Toltecan Family. 1-155 ^ Peruvians, 101 58 75 Mexicans, 22 92 67 79 Barbarous Tribes. ' Iroquois, - 79 Lenape", -161 104 70 84 Cherokee, Shoshone', &c, J J NEGI 10 GROUP. Native African Family, 62 99 65 83 1 83 American-born Negroes, 12 89 73 82 Hottentot Family, 3 83 68 75 Alforian Family, } * Australians, 83 63 75 MENTAL FACULTIES.—SIZE OF THE BRAIN. 177 From this table it appears, that the smallest mean cranial capacity is found in the Hottentots and Australians, which is 75 cubic inches ; whilst that of the Teutonic races is 92 cubic inches. It may be inte- resting to add, that from the examination of four skulls of the Enge- ena, a quadrumanous animal—Troglodytes gorilla, of Savage—from Gaboon in Africa, Dr. Jeffries Wyman1 found the mean capacity, mea- sured according to the method employed by Dr. Morton, to be 28*9J cubic inches, or considerably less than one-half the mean of the Hot- tentots and Australians, who afford the minimum average for the hu- man family. The mean cranial capacity of three adult chimpanzees was even less, or 24 cubic inches. Wrisberg and Sommering2 proposed another point of comparison— the ratio of the mass of the encephalon to that of the rest of the nervous system; and they asserted, that in proportion as any animal possesses a larger share of the former; or, in other words, in proportion as the percipient and intellectual organ exceeds the other or the organ of the external senses, the mental sphere may be expected to be more diver- sified and developed. But although man is, in general, pre-eminent in this respect, he is not absolutely so. It would be still more important to know the ratio, which the cerebrum or brain proper bears to the cerebellum and medulla oblongata. The first is essen- tially the organ of intellect; and the most striking character of the human brain is the large developement of the cerebral hemispheres, of which we have no parallel in the animal king- dom. The last is the encephalic part in which the nerves of sense arise or terminate. The assertion, that man has the largest cerebrum in propor- tion to the cerebellum, is not accurate. The Wenzels3 found the ratio, in him, to be as Qfs^ or 8j422r to 1; in the horse, 4 J to 1; in the cow, 5if f to 1; in the dog. 634g to 1 ; in the cat, 4T45 to 1; in the mole, 3f to 1; and in the mouse, 6§ to 1. Nor is it true that man has the largest cerebrum in proportion Fig. 319. Facial Line and Angle of Mnn. 1 A description of two additional Crania of the Enge-ena, &c, read before the Boston Society of Natural History, Oct. 3, 1849 ; and published in the American Journal of Science and Arts, s«cond series, vol. ix. 2 Corpor. Human. Fabric, iv. § 92 ; and Blumenbach's Comp. Anat. by Lawrence, p. 292, Lond., 1807. 3 De Penitiori Structur. Cerebr. Hominis et Brutorum, tab. iv. VOL. II.—12 178 SENSIBILITY. Vertical section of Skull of Papuan Negrito. to the medulla oblongata and medulla spinalis; although to this position there are perhaps fewer objections than to the others. None of them, it is obvious, are distinct- Fig- 320. ive between man and ani- mals, or assist us in solving the great problem of the source and seat of the nu- merous psychical differ- ences we observe. Various plans have been devised for appreciating the comparative size of the cranium,—which is generally in a ratio with that of the brain,—and of the bones of the face. As the former contains the organ of the intellect, and the latter those of the ex- ternal senses and of masti- cation, it has been presumed, that the excess of the former would indi- cate the predominance of thought over the senses; and, conversely, that the greater developement of the face would place the animal lower in the scale. One of these methods, first proposed by Camper,1 is by taking the course of the facial line, and the amount of the facial angle. The facial line is a line drawn from the projecting part of the forehead to the alveoli of the incisor teeth of the upper jaw; the facial angle is that formed be- tween this line and another drawn horizon- tally backwards from the upper jaw. The course of the horizontal line and its point of union with the facial line are not uni- form in all the figures given by Camper: sometimes, it is made to pass through the meatus auditorius externus; but it often falls far below it; yet Dr. Bostock thinks* " we cannot hesitate to admit the correct- ness of Camper s observations, and we can scarcely refuse our assent to the conclusion that he deduces from them." In man, whose face is situate perpendicularly under the cranium, the facial angle is very large. In animals, the face is placed in front of the cranium; and as we descend from man the angle becomes less and less, until it is finally lost; the cranium and face being in most reptiles and fish on a level. The marginal figure (Fig. 319) exhibits the difference between 1 Dissertation Physique de M. Camper, sur les Differences Reelles que presentent les Traits du Visage, &c, traduit du Hollandois, par D. B. Q. Disjonval, Autrecht 1791. 2 Physiology, 3d edit., p. 804, Lond., 1836. Fig. 321. Facial Line and Angle of the Ourang-Outang. MENTAL FACULTIES.—FACIAL LINE AND ANGLE. 179 the facial angle of one of European descent, and that of the negro. By covering with the finger the parts below the nose alternately, we have the countenance of the white, and negro, in which the facial angle differs as much as 10°, or 15°. Figs. 321, 2, 3, exhibit the facial line Fig. 322. Fig. 323. Vertical section of Skull of Adult Ourang. Vertical section of Skull of Young Ourang. and angle of the ourang-outang. Animals that have the snout long, and the facial angle consequently small, have been proverbially es- teemed foolish:1—such are the snipe, stork, crane, &c; whilst superior intelligence has been ascribed to those in which the angle is more largely developed,—as the elephant and the owl; although in them, the large facial angle is caused by the size of the frontal sinuses, or by the wide separation between the two tables of the skull, and is neces- sarily no index of the size of the brain. Yet, from this cause, perhaps, the owl was chosen as an emblem of the goddess of wisdom; and the elephant has received a name in the Malay language, indicating an opinion, that he is possessed of reason. The following table exhibits the facial angle in man and certain animals, taken by a line drawn parallel to the floor of the nostrils, and meeting another, drawn from the greatest prominence of the alveoli of the upper jaw to the promi- nence of the forehead:— Man ... 68° to 88° or more Sapajou......65° Ourang-outang . . . 56° or 58° Guenon......57° Mandril.....30° to 42° Coati......28° Polecat Pug dog Mastiff . Hare Ram Horse . 31° 35° 41° 30° 30° 23° The facial angle may, then, exhibit the difference between man and animals; and, to a certain extent, between the species or individuals of the latter; but, farther, it is of little or no use.2 In man, it may be considered to vary from 70° to 85° in the adult; but in children it 1 Lawrence, op. citat., p. 168. 2 Dr. Morton, in his splendid work, Crania Americana, Philad., 1839, describes a " Facial Goniometer," originally suggested by Dr. Turnpenny, of Philadelphia, which is admirably adapted for measuring the facial angle. 180 SENSIBILITY. reaches as high as 90° and upwards; a sufficient proof, that it cannot be regarded as a measure of the intellect. In the European, it has been estimated, on the average, at perhaps, 80°, in the Mongol, 75°, and in the negro, 70°, not many degrees above the Sapajou.1 The following table, drawn up from the average of actual measure- ments of the skulls of different races and families of man, in the collec- tion of Dr. Morton,2 will afford more precise information on this matter. FACIAL ANGLE. Average. Highest. Lowest. Arab (2 cases)......82 88 76 European and Anglo-American .... 80 85 77 Egyptian........79-3 86 73 Bengalee........79-3 83 76 Circassian ....... 78-5 81 75 Sandwich Islander (one case) .... 78 Chinese (one case) ...... 78 Guanche (one case) ..... 77 Negro........76-8 83 69 Indian........76-1 84 70 Hottentot (one case) ..... 75 Peruvian........74-9 81 68 Malay........74.6 82 69 It is found, that the skulls of different nations, and of individuals of the same nation, may agree in the facial angle, whilst there may be striking distinctions in the shape of the cranium and face, in the air and character of the whole head, as well as in the particular features,— the inclination of the facial line being more dependent on the promi- nence of the upper jaw and frontal sinuses than on the general form of the head. The ancients were impressed with the intellectual air exhi- bited by the open facial angle: for we find in all their statues of legis- lators, sages, and poets, an angle of at least 90°, and in those of heroes and superhuman natures it is as high as 100°. This angle, according to Camper, never existed in nature; and yet he conceives it to be the beau ideal of the human countenance, and to have been the ancient model of beauty. It was, more probably, the model of superior intel- lectual endowment, although ideas of beauty might have been con- nected with it. Every nation forms its notions of beauty, derived from this source, chiefly from the facial angle to which it is accustomed. With the Greeks it was large, and therefore the vertical facial line was highly estimated. For the same reason, it is pleasing to us; but such would not be the universal impression. Savage tribes on our own continent have preferred the pyramidal shape of the head, and made use of every endeavour, by unnatural cpmpression in early infancy, to produce it; whilst others, not satisfied with the natural shape of the frontal bone, have forced back the forehead, either by applying a flat piece of board to it, like the Indians of our own continent, or by iron plates, like the inhabitants of Arracan. By this practice the Caraibs are said to be able to see over their heads. M. Daubenton,3 again, endeavoured, by taking the occipital line and angle, to measure the differences between the skulls of man and ani- 1 Prichard's Physical History of Mankind, i. 288, 3d edit., Lond., 1836. 2 Catalogue of Skulls of Man, &c, 3d edit., Philad., 1849. i Memoires de l'Acad. mie des Sciences de Paris, p. 568, Paris, 1764. MENTAL FACULTIES.—VIEWS OF PHRENOLOGISTS. 181 mals. A line is drawn from the posterior margin of the foramen magnum of the occipital bone to the inferior margin of the orbit, and another from the top of the head to the space between the occipital condyles. In man, these condyles, as well as the foramen magnum, are so situate, that a line drawn perpendicular to them will be a con- tinuation of the vertebral column ; but in animals they are placed more or less obliquely; the perpendicular will, therefore, necessarily be thrown farther forward, and the angle be rendered more acute.1 Blumenbach says, that Daubenton's method may be adapted to mea- sure the degrees of comparison betwixt man and brutes, but not vari- eties of national character; for he found it even different in the skulls of two Turks, and three Ethiopians. The methods of Camper and Daubenton combined were, also, insufficient to indicate the varieties in national and individual character. He accordingly describes a new method,—which he calls norma verticalis.2 It consists in select- ing two bones ; the frontal from those of the cranium, and the superior maxillary from those of the face ; comparing these with each other, by regarding them vertically, placing the great convexity of the cranium directly before him, and marking the relative projections of the maxil- lary bone beyond the arch of the forehead. The Asiatic Georgian is found to be characterized by the great expanse of the upper and outer part of the cranium, which hides the face. In the Ethiopian, the nar- row, slanting forehead permits the face to appear, whilst the cheeks and jaws are compressed laterally and elongated in front; and in the Tungoose, the maxillar}'-, malar, and nasal bones are widely expanded on each side; and the two last rise to the same horizontal level with the space between the frontal sinuses—the glabella. Blumenbach's method, however, only affords us the comparative dimensions of the two bones in one direction. It does not indicate the depth of either, or their comparative areas. The view thus obtained is, therefore, partial. Finding the inapplicability of other methods to the greater part of the animal creation—to birds, reptiles, and fishes, for example—M. Cuvier3 suggested a comparison between the areas of the face and cranium under the vertical section of the head. The result of his ob- servations is—that, in the European, the area of the cranium is four times that of the face, excluding the lower jaw. In the Calmuck, the area of the face is one-tenth greater than in the European; in the negro, one-fifth, and in the sapajou, one-half. In the mandril, the two areas are equal; and, in proportion as we descend in the scale of animals, the area of the face gains over that of the cranium; in the hare, it is one-third greater; in the ruminant animals double; in the horse, quadruple, &c.; so that the intelligence of the animal appeared 1 By some writers, Daubenton's method is said to consist of "a line drawn from the posterior margin of the occipital foramen to the inferior margin of the orbit; and another drawn horizontally through the condyles of the occipital bone." It is obvious, that little or no comparative judgment of the cranium and face could be formed from this. 8 Decad. Collections su« Craniorum diversarum Gentium; and De Gener. Human. Var. Nativ., edit. 3a, Gotting., 1795. 3 Lecons d'Anatoinie Compar., No. viii. art. i. torn. ii. p. 1. 182 SENSIBILITY. to be greater or less as the preponderance of the area of the face over that of the skull diminished or increased. The truth, according to Sir Charles Bell,1 is, that the great differ- ence between the bones of the cranium and face in the European and negro is in the size of the jaw-bones. In the negro, these bear a much greater proportion to the head and to the other bones of the face than in the European; and the apparent size of the bones of the negro face was discovered to proceed solely from the size and shape of the jaw-bones; whilst the upper bones of the face, and, indeed, all that had no relation to the teeth and to mastication, were less than those of the European skull. Other methods, of a similar kind, have been proposed by natural- ists, as Spigel,3 Herder,3 Mulder,4 Walther,5 Doornik,6 Spix,7 and Oken, but they are all insufficient to enable us to arrive at a satis- factory comparison.8 Blumenbach asserts, that he found the facial and occipital angles nearly alike in three-fourths of known animals. Moreover, it by no means follows, that, in the same species, there should be a correspondence between the size of the cranium and face. In.the European, the face may be unusually large; and yet the mental endowments may be brilliant. Leo X., Montaigne, Leibnitz, Kacine, Haller, Mirabeau, and Franklin, had all large features.9 All these methods, again, are confined to the estimation of the size of the whole encephalon; whereas the brain, we have seen, is alone concerned in the intellectual and moral manifestations; although Gall includes the cerebellum. It has already been remarked, that no ani- mal equals man in the developement of the cerebral hemispheres. In the ape they are less prominent; and below it in the scale of creation, they become less and less; the middle lobes are less arched down- wards; and the posterior lobes are ultimately wanting, leaving the cerebellum uncovered; the convolutions are less and less numerous and deep, and the brain at length is found entirely smooth. The ex- periments of Rolando of Turin, and Flourens10 of Paris, are likewise confirmatory of this function of the brain proper. These gentlemen experimented upon different portions of the encephalon, with the view of detecting their functions;—endeavouring, as much as possible, not to implicate any part except the one which was the subject of investi- gation; and they found, that if the cerebral hemispheres were alone removed, the animal was thrown into a state of stupor or lethargy; 1 Anatomy of Expression, 3d edit., Lond., 1844. 2 Lme.ae Cephalometricae Spigelii, in Spigel, De Human. Corpor. Fabric, i. 8. 3 Nackenlinien (Linese nuchales Herderi), in Herder's Ideen zur Philosophic der Geschichte der Menschheit, Th. iii. S. 186, Tubing., 1806. 4 Vorderhauptwinkel (Angulus sincipitalis Mulderi), in art. Kopfiinien, in Pierer'a Anat. Physiol. Real Worterb., iv. 524, Leipz., 1821. 6 Schadelwinkel (Angulus Cranioscopicus Waltheri), in Walther, Kritische Darstel- lung der Gallschen Anat. Physiol. Untersuch. des Gehirn und Schiidelbaues, S. 108, > Zurich, 1802. 6 Wijsgeerig Natuurkundig Onderzoek aangande den Oorsprongliken Menscli en de Oorspronglike Stammen van deszelfs Geslacht, Amsterd., 1808. 7 Cephalogenesis, Monach., 1815. 8 Oken, Lehrbuch der Zoologie, Abth. ii. S. 660. A description of all these methods is given by Choulant, in Pierer, loc. cit. 9 Gall, Sur les Fonctions du Cerveau ii. 296. 10 Recherches Exp rimentales sur le Systeme Nerveux, 2de edit., Paris 1842. MENTAL FACULTIES.—VIEWS OF PHRENOLOGISTS. 183 was insensible to all impressions; to every appearance asleep, and evidently devoid of all intellectual and affective faculties. On the other hand, when other parts of the encephalon were mutilated—the cerebellum, for example—leaving the cerebral hemispheres uninjured, the animal was deprived of certain other faculties—that of regulating the movements, for instance—but retained its consciousness, and the exercise of all its senses. M. Desmoulins,' in his observations on the nervous system of verte- brated animals, is in favour of a view, embraced by M. Magendie,2 that the intellectual sphere of man and animals depends exclusively on the cerebral convolutions; and that an examination of the convolu- tions will exhibit the intellectual differences, not only between differ- ent species, but between individuals of the same species. According to him, the cerebral convolutions are numerous in animals in propor- tion to their intelligence; and, in animals of similar habitudes, have a similar arrangement. In the same species, they differ sensibly accord- ing to the degree in which the individuals possess the qualities of their nature:—for example, they vary in the foetus and adult; are mani- festly less numerous and smaller in the idiot; and become effaced in protracted cases of insanity. He farther remarks, that the morbid conditions of the encephalon, which occasion mental aberration, are especially such as act upon the convolutions; and that whilst apoplec- tic extravasation into the centre of the organ induces paralysis of sen- sation and motion, the slightest inflammation of the arachnoid mem- brane causes delirium. Hence, he deduces the general principle, that the number and perfection of the intellectual faculties are in a ratio with the extent of the cerebral surfaces. It would seem, however, from some experiments by M. Baillarger,3 that the amount of intel- lectual developement in man, and in the various classes of animals, is far from being proportionate to the extent of surface presented by the brain of each. That of man, for instance, has, in proportion to its volume, a much less extent of surface than the brains of the lower mammalia; and the brain of the rabbit has, in proportion to its volume, an extent of surface two and a half times greater than that presented by the brain of man. The view of M. Desmoulins, so far as regards the seat of the intel- lectual and moral faculties, accords with one to which attention must now be directed; and which has given rise to more philosophical in- quiry, laborious investigation, and, it must be admitted, to more idle enthusiasm and intolerant opposition, than any of the psychological doctrines advanced in modern times: we allude to the views of M. Gall.4 These are, 1st, That the intellectual and moral faculties are innate. 2dly, That their exercise or manifestation is dependent upon organization. Bdly, That the encephalon is the organ of all the appe- tites, feelings, and faculties; and, 4thly, That the encephalon is com- posed of as many particular organs as there are appetites, feelings, and faculties, differing essentially from each other. 1 Anatomie des Systemes Nerveux des Animaux a Vertebres, Paris, 1825. 2 Precis Llumentaire, edit, cit., i. 185. • 3 Revue M'dicale, Mai, 1845. * Sur les Fouctions du Cerveau, Paris, 1825. 184 SENSIBILITY. The importance of Gall's propositions; the strictly physiological direction they have taken—the only one, as we have said, which ap- pears likely to aid us in our farther acquaintance with the psychology of man—require that the physiological student should have them placed before him as they emanated from the author. The work of Gall on the functions of the encephalon comprises, however, six octavo volumes, not distinguished for unusual method or clearness of exposi- tion. Fortunately, the distinguished biologist, M. Adelon, to whom we have so frequently referred, has spared us the necessity of a tedious and difficult analysis, by the excellent and impartial view he has given in the Dictionnaire de MeHecine,1 which has since been transferred to his Physiologie de VHomme; both being abridgments of the Analyse d^un Cours du Dr. Gall, published by him in 1808. The foundation of this doctrine is, that the encephalon is not a sin- gle organ, but is composed of as many nervous systems* as there are primary and original faculties of the mind. In the view of Gall, it is a group of several organs, each of which is concerned in the produc- tion of a special moral act: and, according as the encephalon of an animal contains a greater or less number of organs, and of a greater or less degree of developement, the animal has, in its moral sphere, a greater or less number of, or more or less active, faculties. In like manner, as there are as many sensorial nervous systems and organs of sense as there are external senses, so there are, it is maintained, as many encephalic nervous systems as there are special moral faculties or internal senses. Each moral faculty has, in the encephalon, a nervous part concerned in its production; as each sense has its special nervous system; the sole difference being, that the nervous systems of the senses are separate and distinct, whilst those of the encephalon are crowded together in the small cavity of the cranium, and appear to form but one mass. * The proofs adduced by Gall2 in favour of his proposition are the following:—1st. It has been established as a principle, that differences in the psychology of man and animals correspond to varieties in the structure of the encephalon, and that the latter are dependent on the former. Now, differences of the encephalon consist less in changes of the general form of the organ, than in parts, which are present in some and not in others; and if the presence or absence of such parts is the cause why certain animals have a greater or less number of faculties than others, they ought certainly to be esteemed special organs of such faculties. 2dly. The intellectual and moral faculties are multiple. This every one admits. Each, consequently, ought to have its special organ; and the admission of a plurality of intellectual moral faculties must induce that of a plurality of encephalic organs, in the same man- ner as each external sense has its proper nervous system. 3dly. In different individuals of the same species,—in different men,—much psychological variety is observable. The cause of this is doubtless in the encephalon; but we can hardly ascribe it to a difference in the 1 Art. Encephale (Physiologie), Paris, 1823, and art. Facultes de l'Esprit et de PAme, &c, in Diet, de Medecine, viii. 469, Paris, 1823. 2 Op. cit., ii. 394. MENTAL FACULTIES.—VIEWS OF PHRENOLOGISTS. 185 general shape of the organ, which is sensibly the same. It is owing rather to differences in its separate parts. Are not such parts, .there- fore, he asks, disti net nervous systems ? 4thly. In the same individual— in the same man—the intellectual and affective faculties have never the same degree of activity; whilst one predominates, another may be feeble. Now, this fact, which is inexplicable under the hypothesis, that the encephalon is a single organ, is readily intelligible under the theory of the plurality of organs. Whilst the encephalic part, which is the agent of the one faculty, is proportion ably more voluminous or more active, that which presides over the other is less so. Why, he asks, may not this happen with the encephalic organs, as with the other organs of the body,—the senses, for example ? Cannot one of these be feeble, and the other energetic? 5thly. In the same indi- vidual, all the faculties do not appear, nor are they all lost at the same period. Each age has its own psychology. How can we explain these intellectual and moral varieties according to age, under the hypothesis that the encephalon is a single organ? Under the doctrine of the plurality of encephalic organs, the explanation is simple. Each ence- phalic system has its special period of developement and decay. Gthly. It is a common observation, that when we are fatigued by one kind of mental occupation, we have recourse to another; yet it often happens, that the new labour, instead of adding to the fatigue experienced by the former, is a relaxation. This, Gall remarks, would not be the case if the encephalon were a single organ, and acted as such; but it is readily explicable under the doctrine of plurality of organs. It is owing to a fresh encephalic organ having been put in action. 7thly. Insanity is frequently confined to one single train of ideas, as in the variety called monomania, which is often caused by the constancy and tenacity of an original exclusive idea. This is frequently removed by exciting another idea opposed to the first, which distracts attention from it. Is it possible, Gall asks, to comprehend these facts under the hypothesis of unity of the encephalon ? 8thly. Idiocy and dementia are often only partial, and it is not easy to conceive, under the idea of the unity of the encephalon, how one faculty remains amidst the abolition of all the others. 9thly. A wound or a physical injury of the encephalon frequently modifies but one faculty, paralyzing, or aug- menting it, and leaving every other uninjured. lOthly, and lastly. Gall invokes the analogy of other nervous parts; and, as the great sympathetic, medulla oblongata, and medulla spinalis are—in his view at least—groups of special nervous systems, it is probably, he says, the same with the encephalon. Such are the main arguments employed by Gall for proving, that the encephalon consists of a plurality of organs, each of which is con-, cerned in the production of a special intellectual or moral faculty; and should they not carry conviction, it must be admitted that many of them are ingenious and forcible, and all merit attention. It is a prevalent idea, that this notion of a plurality of organs is a fantasy, which originated with Gall. Nothing is more erroneous: he has adduced the opinions of numerous writers who preceded him, some of whom have given figures of the cranium, with the seats of the dif- ferent organs and faculties marked upon it. To this list might be 186 SENSIBILITY. added numerous others. Aristotle, in whose works are found the germg of many discoveries and speculations, thought that the first or anterior ventricle of the brain, was the ventricle of common sense; because, from it, according to him, the nerves of the five senses branched off. The second ventricle, connected by a minute opening with the first, he designated as the seat of imagination, judgment and reflection ; and the third, as a storehouse into which the conceptions of the mind, digested in the second ventricle, were transmitted for retention and accumu- lation; he regarded it as the seat cf memory. Bernard Gordon, in a work written in 1296, gives nearly the same account of the brain. It contains, lie says, three cells or ventricles. In the anterior part of the first lies common sense; the function of which is to take cognizance of the various forms and images received by the several senses. In the posterior part of the first ven- tricle he places phantasia; and in the anterior part of the second, imagina- tiva; in the posterior part of the middle lies estimativa. It would be a waste of time and space, to adduce the absurd notions entertained by Gordon on this subject. He thinks there are three fa- culties or virtues—imaginatio, cogiiatio, and memoria—each of which has a spe- cial organ engaged in its production. For many centuries it was believed, that the cerebrum was the organ of perception, and the cerebellum that of memory. Albert the Great, in the thir- teenth century, sketched a head on which he represented the seat of the different intellectual faculties. In the forehead and first ventricle he placed common sense and imagination; in the second intelligence and judgment; and in the third, memory and the motive force. The head in the margin (Fig. 324) is from an old sketch contained in the Book Rarities of the University of Cam- bridge. Servetus conceived, that the two anterior cerebral cavities are for the reception of the images of external objects; the third is the seat of thought; the aqueduct of Sylvius, the seat of the soul; and the fourth ventricle that of memory. In 1491, Peter Montagnana published an engraving, in which were represented the seat of the sensus communis, a cellula imaginativa, cellula estimativa seu cogitativa, a cellula memorativa, and a Old Phrenological Head. Fig. 325. Olfactu 5 GurfuSGsi Phrenological Head by Dolci, A. D. 1562. MENTAL FACULTIES.—VIEWS OF PHRENOLOGISTS. 187 cellula rationalis. A head by Ludovico Dolci exhibits a similar arrange- ment. (Fig. 325.)1 The celebrated Dr. Thomas Willis, in 1681, asserted, that the cor- pora striata are the seat of perception; the medullary part of the brain that of memory and imagination; the corpus callosum that of reflection; and the cerebellum furnished the vital spirits necessary for the involun- tary motions.2 It would appear, too, that Swedenborg, half a century before the promulgation of Gall's theory, maintained the doctrine, that every man is born with a disposition to all sorts of evil, which must be checked by education, and, as far as possible, rooted out; and that the degree of success or failure in this respect would be indicated by the shape of the skull. "The peculiar distinctions of man, will and the understanding," he argued, "have their seats in the brain, which is excited by the fleeting desires of the will, and the ideas of the intellect. Near the various spots where these irritations produce their effects, this or that part of the brain is called into a greater or less degree of activity, and forms along with itself corresponding parts of the skull."3 This view, that exercise of the encephalic organs occasions their de- velopement in bulk, and want of due exercise their decrease, is now maintained by many phrenologists; but denied by others. The above examples are sufficient to show, that the attempt to assign faculties to different parts of the brain; and, consequently, the belief, that the brain consists of a plurality of organs, had been long indulged by anatomists and philosophers. The views of Gall are resuscitations of the old; but resembling them little more than in idea. Those of the older philosophers were the merest fantasies, unsupported by ob- servation : the speculations of the modern physiologists have certainly been the result of long and careful investigation, and deep meditation. Whilst, therefore, we may justly discard the former, the latter are worthy of careful and unprejudiced examination. Admitting, with M. Gall, the idea of the plurality of organs, in the encephalon, the inquiry would next be,—how many special nervous systems are there in that of man, and what are the primary intellectual and moral faculties over which they preside? This Gall has attempted. To attain this double object, he had two courses to adopt;—either, first to indicate anatomically the nervous systems that constitute the encephalon; and then to trace the faculties of which they are the organs; or, contrariwise, to point out first the primary faculties, and afterwards to assign to each an organ or particular seat. The first course was impracticable. The encephalic organs are not distinct, isolated: and if they were, simple inspection could not indicate the faculty over which they preside, any more than the appearance of a nerve of sense could indicate the kind of sensation for which it is des- tined. It was only, therefore, by observing the faculties, that he could arrive at a specification of the primary encephalic organs. But here, again, a source of difficulty arose. How manj'- primary intellectual and 1 See Burton's Anatomy of Melancholy, 11th edit., i. 32, Lond., 1813; and Margarita Philosophica, lib. ix. cap. 40, Basil., 1508, cited by Dr. John Redman Coxe, in Dungli- son's American Medical Intelligencer, i. 58, Philad., 1838. 1 Gall, Sur les Fonctions du Cerveau, ii. 350, Paris, 1835. * Dr. Scwall, Examination of Phrenology, 2d edit., p. 14, Boston, 1839. 188 SENSIBILITY. moral faculties are there in man? and what are they? The classifi- cations of the mental philosophers,—differing, as we have seen they do, so intrinsically and essentially from each other,—could lead him to no conclusion. He first, however, followed the views on which they appeared to be in accordance; and endeavoured to find particular organs for the faculties of memory, judgment, imagination, &c. But his researches in this direction were fruitless. He, therefore, took for his guidance the common notions of mankind; and having regard to the favourite occupations, and different vocations of individuals; to those marked dispositions, which give occasion to the idea, that a man is born a poet, musician, or mathematician, he carefully examined the heads of such as presented these predominant qualities, and endeavoured to discover in them such parts of the encephalon as were more prominent than usual, and might be considered as special nervous systems,—or- gans of those faculties. After multitudinous empirical researches on living individuals, on collections of crania, and casts made for the purpose; attending particularly to the heads of such as had one of their faculties predominant, and who were, as he remarks, geniuses on one point,—to the maniac, and the monomaniac;—after a sedulous study, likewise, of the heads of animals, comparing especially those that have a particular faculty with such as have it not, in order to see if there did not exist in the encephalon of the former some part which was wanting in that of the latter; by this entirely experimental method, he ventured to specify, in the encephalon of animals and man, a certain number of organs; and, in their psychology, as many faculties, truly primary in their character. But, in order that such a mode of investigation be applicable, it must be admitted, 1st. That one of the elements of the activity of a function is the developement of its organ. 2dly. That the encephalic organs end, and are distinct, at the surface of the encephalon. And 3dly. That the cranium is moulded to the encephalon, and is a faithful index of its shape; for it is, of course, through the skull and the integuments covering it, that Gall attempts, in the living subject, to appreciate the state of the encephalon. Within certain limits, these positions are true. In the first place, we judge of the activity of a function, by the size of the organ that executes it: the greater the optic nerve, the more acute we expect to find the sense of sight. In the second place, according to the anato- mical theory of Gall, the encephalic convolutions are the final expan- sions of the encephalon: if we trace back the original fasciculi, which, by their terminations, form the hemispheres of the brain, they are observed to increase gradually in size in their progress towards the circumference of the organ, and to end in the convolutions. Lastly, to a certain extent the cranium is moulded to the encephalon; and participates in all the changes which the latter undergoes at different periods of life and in disease. For example, during the first days after the formation of the encephalon of the foetus, the cranium is mem- branous, and has exactly the shape of that viscus. On this membrane, ossific points are deposited, so that, when the membrane has become bone, the cranium has still the shape of the encephalon. In short, nature having made the skull to contain the encephalon, has fitted the MENTAL FACULTIES.—VIEWS OF PHRENOLOGISTS. 189 one to the other, and this so accurately, that its internal surface exhi- bits sinuosities corresponding to the vessels that creep on the surface; and digitations corresponding to the encephalic convolutions. The encephalon, in fact, rigidly regulates the ossification of the cranium; and when, in the progress of life, it augments, the capacity of the cranium is augmented likewise; not by the effect of mechanical pres- sure, but owing to the two parts being catenated in their increase and nutrition. This remark applies not only to the skull and encephalon, regarded as a whole, but to their separate parts. Certain portions of the encephalon are not developed simultaneously with the rest of the organ; and the same thing happens to the portions of the skull that invest them. The forehead, for example, begins to be developed after the age of four months; but the inferior occipital fossa? do not increase in proportion until the period of puberty. Again; when the ence- phalon fades and wastes in advanced life, the cavity of the cranium contracts, and its ossification takes place on a less and less outline. In advanced life, however, according to Gall, the correspondence between the encephalon and the inner table of the skull is alone maintained; the table appearing to be a stranger to all nutritive movement, and preserving its dimensions. Lastly, the cranium partakes of all the variations experienced by the encephalon in disease. If the latter be wanting, as in the acephalous monster, the cranium is wanting also. If a portion of the encephalon exists, the corresponding portion of the cranium exists. If the encephalon is smaller than natural, as in the idiot, the cranium is also. If, on the contrary, it is distended by hydro- cephalus, the cranium has a considerable capacity; and this, not owing to a separation, at the sutures, of the bones composing it, but to ossifi- cation taking place on a larger outline. If the encephalon be much developed in any one part, and not in another, the cranium is pro- tuberant in the former,—restricted in the latter; and lastly, in cases of mania, the cranium is often affected, being, for example, unusually thick, dense, and heavy. These reasons, adduced by Gall, may justify the admission, that, within certain limits, the skull is moulded to the encephalon; and, if this be conceded, the method followed by him of specifying the organs of the mental faculties may be conceived practicable. Such is the basis of the system of craniology proposed by Gall. It has also been called cranology, organology, phrenology, and cranioscopy: although, strictly speaking, it is by cranioscopy that we acquire a know- ledge of craniology,—the art of prejudging the intellectual and moral aptitudes of man and animals, from an examination of the cranium. It is, of course, limited in its application. Gall admits, that it is not available in old age, owing to the physiological fact before stated,— that the external table of the skull is no longer modified by the changes, that happen to the encephalon; and he acknowledges, that its employ- ment is always difficult, and liable to errors. We cannot, for example, touch the cranium directly; for it is covered by hair and integument. The skull is made rough, in parts, by muscular impressions; and these roughnesses must not be confounded with what are termed "protu- berances,"—prominences formed by a corresponding developement of the encephalon. In this respect, craniology presents more difficulties 190 SENSIBILITY. in animals, owing to their heads being more covered with muscles, and from the inner table of the skull being, alone, in contact with the encephalon beneath. Other errors may be incurred from the frontal and superior longitudinal sinuses; and from the possible separation of the hemispheres at the median line. The difficulty is, of course, extremely great in appreciating the parts of the encephalon, that are situate behind the eyes; and craniology must be entirely inapplicable to those encephalic organs that terminate at its base. Gall has taken especial pains to remark, that by craniology we can only prejudge the dispositions of men, not their actions; and can appreciate but one of the elements of the activity of organs—their Fig. 326. Fig. 327. Phrenological Organs according to Gall. size,—not what belongs to their intrinsic activity, and to the impulse or spring they may receive from the temperament or general formation. Setting out, however, with the principle, that the predominance of a faculty is in a great measure dependent on the developement of the portion of the encephalon which is its organ, he goes so far as to par- MENTAL FACULTIES.—VIEWS OF PHRENOLOGISTS. 191 ticularize, in this developement, what is owing to the length of the encephalic fibres, and what to their breadth; referring the activity of the faculty to the former, and its intensity to the latter. In applying cranioscopy to animals, he observes, that the same encephalic organ frequently occupies parts of the head, that seem to be very different, on account of the difference between station in animals and man, and of the greater or less number of systems, that compose their encephalon. The following are the encephalic organs enumerated by Gall, with the corresponding faculties:—the numbers corresponding with those of the above illustrations. 1. Instinct of generation, of reproduction; "1 amativeness. Instinct of propagation ; venereal instinct. \ {German.) Z eu gung s t r i eb, Fortpflanzungstrieb, Geschlechtstrieb. J 2. Love of progeny ; philoprogenitiveness. (G.) Jungenliebe, Kinder- lie b e. 3. Attachment,friendship. "J (G.)Freundschaftsinn. ) 4. Instinct of defending self and property ; " love of strife and combat; combative- ness; courage. (G.) Muth, Raufsinn, Zanksinn. 5. Carnivorous instinct; inclination to murder; destructiveness; cruelty. (G.) Wurgsinn, Mordsinn. 6. Cunning; finesse; address; secretive- ness. ((?.) List, Schlauheit, Klug- hei t. 7. Desire of property ; provident instinct; cupidity; inclination to robbery; acqui- sitiveness. (G.) Eigenthums sinn, Hang zu stehlen, Einsammlung s- sinn, Diebsinn. 8. Pride; haughtiness; love of authority; elevation. (G. Stolz, Hochmuth, Hbhen- sinn, Herrschsucht. 9. Vanity; Ambition; love of glory. ( G.) Eitelkeit, Ruhmsucbt, Ehrgeitz. 10. Circumspection ; foresight. (G.) Behutsamkei t, Vorsicht, Vorsichtigkeit. 11. Memory of things; memory of facts; sense of things; educability ; perfectibi- lity ; docility. (G.) Sachgediichtniss, Er- ziehungs f ahigkeit, Sach- s inn. 12. Sense of locality; sense of the relation of space; memory of places. (6'.) Ortsinn, Raumsinn. Seated in the cerebellum. It is manifested at the surface of the cranium by two round protuberances, one on each side of the nape of the neck. Indicated at the external occipital protube- rance. About the middle of the posterior margin of the parietal bone; anterior to the last. Seated a little above the ears; in front of the last, and towards the mastoid angle of the parietal bone. Greatly developed in all the carnivorous animals ; forms a prominence at the pos- terior and superior part of the squamous surface of the temporal bone, above the mastoid process. Above the meatus auditorius externus, upon the sphenoidal angle of the parietal bones. Anterior to that of cunning, of which it seems to be a prolongation, and above that of mechanics, with which it contributes to widen the cranium, by the projection which they form at the side of the frontal bone. Behind the top of the head, at the extre- mity of the sagittal suture, and on the parietal bones. Situate at the side of the last, near the pos- terior internal angle of the parietal bones. Corresponds to the parietal protuberances. Situate at the root of the nose, between the two eyebrows, and a little above them. Answers to the frontal sinuses, and is indi- cated externally by two prominences at the inner edge of the eyebrows, near the root of the nose, and outside the organ of memory of things. 192 SENSIBILITY. 13. Memory of persons; sense of persons. \ (G.)Personensinn. j 14. Sense of words; sense of names; ver- ~| bal memory. (G.) Wor t ge d achtni s s, N a- f mensinn. J 15. Sense of spoken language; talent of] philology ; study of languages. (G.) Sprachforschungssinn, f Wortsinn, Sprachsinn. J 16. Sense of the relations of colour; ta- J lent of painting. \ (G.)Farbensinn. J 17. (Sense of the relations of tones; musi- 1 cat talent. Y (G.) Tonsinn. j 18. Sense of the relations of numbers; \ mathematics. > (G.) Zahlensinn. J 19. Sense of mechanics; sense of construe- ") lion ; talent of architecture; industry. > (G.) Kunstsinn, Bausinn. J 20. Comparative sagacity. 1 (G.) Vergleichender Scharf- j- s i nn. J 21. Metaphysical penetration ; depth of ] mind. 1 (G.) Metaph.ysisch.er Tief- [ s i n n . J 22. Wit. \ (G.) Witz. j 23. Poetical talent. \ (G.)Dichtergeist. j 24. Goodness; benevolence; mildness compassion; sensibility; moral sense conscience ; bonhommie. (G.) Gutmiithigkeit, Mitlei den, moralischer Sinn Gewissen. 25. Imitation; mimicry. (G.) Nachahmungssinn. 26. God and religion ; theosophy. (G.) Theosophisch.es Sinn. 27. Firmness; constancy; perseverance obstinacy. (G.) Stetigkeit, fester Sinn. "1 At the inner angle of the orbit. Situate at the posterior part of the base of the two anterior lobes of the brain, on the frontal part of the bottom of the orhit, so as to make the eye prominent. Also at the top of the orbit, between the pre- ceding and that of the knowledge of colour. The middle part of the eyebrows ; encroach- ing a little on the forehead. A little above and to one side of the last; above the outer third of the orbitar arch. On the outside of the organ of the sense of the relations of colour, and below the last. A round protuberance at the lateral base of the frontal bone, towards the temple, and behind the organs of music and numbers. At the middle and anterior part of the fron- tal bone, above that of the memory of things. In part, confounded with the preceding. In- dicated, at the outer side of this last, by two protuberances, which give to the forehead a peculiar hemispherical shape. At the lateral and outer part of the last; and giving greater width to the frontal prominences. On the outer side of the last; divided into two halves by the coronal suture. Indicated by an oblong prominence above the organ of comparative sagacity; al- most at the frontal suture. At the outer side of the last. At the top of the frontal bone and at the superior angles of the parietal bones, The top of the head; at the anterior and most elevated part of the parietal bones. The first nineteen of these, according to Gall, are common to man and animals: the remaining eight man possesses exclusively. They are, consequently, the attributes of humanity. Dr. Spurzheim,1 a fellow-labourer with Gall, who accompanied him in his travels, and was associated with him in many of his publications, added other faculties, so as to make the whole number thirty-five; but they were not embraced by Gall; indeed, several of the positions of Spurzheim are repudiated by Gall's followers.2 The organs admitted by Spurzheim are given on the next page: the numbers correspond with those of the illustrations. On the situation of the different encephalic organs, Gall remarks,— 1 Phrenology, Amer. edit., Boston, 1833. 2 Elliotson, Human Physiology, p. 384, and 1147, London, 1840. MENTAL FACULTIES—VIEWS OF PHRENOLOGISTS. 193 1st. That those which are common to man and animals are seated in parts of the encephalon common to both:—at the posterior, inferior, and anterior inferior, portions. On the contrary, those, that are exclu- sive to man, are situate in parts of the encephalon that exist only in Fig. 329. Fig. 330. Phrenological Organs according to Spurzheim. 1. Amativeness. 2. Philoprogenitiveness. 3. Inhabitiveness. 4. Adhesiveness or Attachment. 5. Combativcness. 6. Destructiveuess. 7. Constructiveness. 8. Acquisitiveness. 9. Secretiveness. 10. Self-Esteem. 11. Love of Approbation. 12. Cautiousness. 13. Benevolence. 14. Veneration. 15. Firmness. 16. Conscientiousness or Justice. 17. Hope. IS. Marvellousness. ]9. Wit. 20. Ideality. 21. Imitation. 22. Individuality. 23. Form. 24. Size. 25. Weight and Resistance. 26. Colour. 27. Locality. 28. Numeration. 29. Order. 30. Eventuality. 31. Time. 32. Melody or Tune. 33. Lan- guage. 34. Comparison. 3-3. Causality. him ;—in the anterior superior parts, which form the forehead. 2dly The more indispensable a faculty, and the more important to the ani- mal economy, the nearer is its organ to the median line, and to the base of the encephalon. 3dly, and lastly. The organs of the faculties, VOL. ii.—13 73575� 6303 194 SENSIBILITY. that aid, or are similar to each "other, are generally situate in prox- imity. In his exposition of each of these organs, and of the reasons that in- duce him to assign it as the seat of a special faculty, he sets out,—first by demonstrating the necessity of the faculty, which he regards as funda- mental and primary, and to which he assigns a special nervous system or organ in the encephalon. 2dly. He endeavours to show, that this faculty is really primary. He considers it to be such, whenever psychi- cal facts show, that it1 has its exclusive source in organization; for example, when it is not common to all animals and sexes; when, in the one possessing it, it does not exhibit itself in a ratio with the other faculties; has its distinct periods of developement and decrease; and does not, in this respect, coincide with the other faculties; when it can be exerted, be diseased, and continue sound alone, or be transmitted alone from parent to child, &c. Lastly, he points out the part of the encephalon, which he considers to be its organ, founding his decision on numerous empirical observations of the encephalon of men and ani- mals, that have possessed, or been devoid of, the faculty and organ in question; or have had them in unequal degrees of developement. It is impossible, in a work of this kind, to exhibit all the views of Gall, and the arguments he has adduced in favour of the existence of his twenty-seven faculties. The selection of one—the instinct of gene- ration—will be sufficient to show how he treats of the whole. Gall's instinct of generation is that, which, in each animal species, attracts the individuals of different sexes towards each other for the purpose of effect- ing the work of reproduction. The necessity for such an impulse for the general preservation of animals is manifest. It is to the continuance of the species what the sensation of hunger is to that of the individual. Again: it is certainly primary and fundamental, for it is independent of all external influence. It does not make its appearance until puberty, and disappears long before other faculties. In many animals it returns periodically. In each animal species, and in each individual, it has a spscial and different degree of energy; although external circumstances may be much the same in all, or at least may not present differences in any manner proportionate to those of the instinct. It may be either alone active, amidst the languor of other faculties; or may be alone languishing. Lastly, it cannot be referred to the genital organs, for it has been observed in children, whose organs have not been developed; it has frequently continued to be felt in eunuchs; and has been expe- rienced by females, who, owing to original monstrosity, have had neither -ovary [?] nor uterus. The part of the encephalon which is the organ of the instinct, is, according to Gall, the cerebellum. His reasons for this belief are the following. 1 st. In the series of animals, a cerebel- lum exists only in those which are reproduced by copulation, and which, consequently, must have the instinct in question. 2dly. There is a per- fect coincidence between the periods at which the cerebellum becomes developed, and the appetite appears. In infancy, it does not exist; and the organ is therefore small. 3dly. In every species of animal and in every individual, there is a ratio between the size of the cere- bellum and the energy of the inclination. In males, in whom it is generally more imperious, the cerebellum is larger. 4thly. A ratio MENTAL FACULTIES—VIEWS OF PHRENOLOGISTS. 195 exists between the structure of the cerebellum and the kind of genera- tion. In oviparous animals, for instance, the cerebellum is smaller at its median part; and it is only in the viviparous, that hemispheres exist. 5thly. A similar ratio obtains between the cerebellum and exter- nal genital organs. If the latter are extirpated at an early age, the de- velopement of the cerebellum is arrested, and it continues small for the remainder of life. Neighbouring parts, which are attributes of the male sex, as the horns of the stag, and the crest of the cock, are often similarly stunted. On the other hand, the cerebellum, in its turn, exerts an intimate influence on the venereal appetite; and modifies the external genital organs. Injuries of the cerebellum either render the person impotent, or excite erotic mania. In nymphomania, the patient often complains of acute pain in the nape of the neck; and this part is more tumid and hot in animals at the rutting season. Gall asserts, that he had noticed in birds, that the cerebellum is not the same in size and excitement during the season of love as at other times; and he affirms, that if erection be observed in those who are hanged, or in consequence of the application of a blister or a seton to the nape of the neck, or of the use of opium, or in such as are threatened with apoplexy, especially when the apoplexy is cerebellous,1 or during sleep, the effect is, in all these cases, owing to congestion of blood in the brain in general, and in the cerebellum in particular. From these data Gall concludes, that the cerebellum is the organ of the instinct of reproduction ; and he remarks, that as this organ presides over one of the most important faculties, it is situate on the median line; and at the base of the skull. In this manner, he proceeds, with more or less success, in his investigation of the other cerebral organs and faculties. But Gall does not restrict himself to the physiological applications of his system. He endeavours to explain the differences that exist between him and other philosophers. He rejects the primary faculties of instinct, intelligence, will, liberty, reason, perception, memory, judgment, &c, of the metaphysician, as mere generalizations of the mind, or common attributes of the true primary faculties. Whilst, in the study of physics, the general and special qualities of matter have been care- fully distinguished, and the latter have been regarded as alone deciding the particular nature of bodies, the metaphysician, says Gall, has re- stricted himself to general qualities, bor example, it is asserted, that " to think is to feel." Thought is, doubtless, a phenomenon of sensi- bility ; but it is a sensitive act of a certain kind. To adhere rigidly to this expression, says Gall, is but to express a generality, which leaves us in as much ignorance as to what thought is, as we should be of a quadruped or bird, by saying that it is an animal; and as, to become acquainted with such animals, their qualities must be speci- fied, so to understand thought, the kind of sensation that constitutes it must be specified. Instinct, according to him, is a general expression, $ 1 A case of Arachnitis Cerebelli—in which there was genital excitement—is reported by the author, in Lond. Med. Rep. for Oct., 1822. For cases of cerebellous disease, without genital excitement, see Duplay, in Archives Generates de Medecine, Nov., 1836 ; Muller's Elements of Physiology, by Baly, 1st edit., p. 833, Lond., 1838 ; and Longet, Anat. et Physiol, du Systeme Nerveux, torn. i. Paris, 1842 ; and Trait j de Physiologie, ii. 267, Paris, 1850. 196 SENSIBILITY. denoting every kind of internal impulse; and, consequently, there must be as many instincts as there are fundamental faculties. Intel- ligence is likewise a general expression, designating the faculty of knowledge; and as there are many instincts, so there are many kinds of intelligence. Philosophers, he thinks, have erroneously ascribed instinct to animals, and intelligence to man. All animals have, to a certain extent, intelligence; and in man many faculties are instincts. Neither is the will a fundamental faculty. It is only a judgment formed amongst several motives, and the result of the concourse of actions of several faculties. There are as many desires as faculties, but there is only one will, which is the product of the simultaneous action of the intellectual forces. So that the will is frequently in op- position to the desires. The same may be said of liberty and reason; to the former applies what has been remarked of the will, and the latter is only the judgment formed by the superior intellectual faculties. In. this respect, however, he remarks, it must not be confounded with in- telligence : many animals are intelligent, but man alone is rational. On the other hand, what are termed, in the intellect, perception, memory, judgment, imagination, &c, are attributes common to all the intellectual faculties; and cannot, consequently, be considered primary faculties. Each faculty has its perception, memory, judgment, and imagination; and, therefore, there are as many kinds of perception, memory, judgment, and imagination, as there are primary intellectual faculties. This is so true, says Gall, that we may have the memory and the judgment perfect upon one point, and totally defective upon another. The memory of musical tones, for instance, is not the same as that of language; and he who possesses the one may not have the other. The imaginations, again, of the poet, musician, and philoso- pher, differ essentially from each other. These faculties are, therefore, according to him, nothing more than different modes of the activity of all the faculties. Each faculty perceives the notion to which it has been attracted, or has perception ; each preserves and renews the recol- lection of this notion, or has memory. All are disposed to act without being excited to action from without, when the organs are largely developed, or have considerable intrinsic activity: this gives rise to imagination; and, lastly, every faculty exerts its function with more or less perfection, whence results judgment. Attention, in his view, is only the active mode of exercise of the fundamental faculties of the intellect; and being an attribute of all it cannot be called a primary faculty. As regards the affective faculties, or what have been called the pas- sions and affections, Gall, in the first place, asserts, that the term passion is faulty when used to indicate a primary faculty. It ought only to designate the highest degree of activity of any faculty. Every faculty requires to be put into action, and according'to the degree of activity which it possesses, it is a desire, a taste, an inclination, a want, or a pas- sion. If it be only of the medium energy, it is a taste: if extremely active, a passion. There may, consequently, be as many passions as there are faculties. We speak of a passion for study, or a passion for music, as we do of the passion of love, or of ambition. Gall objects, also, to the word affection, which, according to him, expresses only the MENTAL FACULTIES—VIEWS OF PHRENOLOGISTS. 197 modifications presented by the primary faculties, according to the mode in which external and internal influences affect them. Some of these are common to all the faculties, as those of pleasure and pain. Every faculty may be the occasion of one or the other. Other affections are special to certain faculties; as pretension, which, he says, is an affection of pride, and repentance an affection of the moral sense. Finally, affec- tions are simple or compjound: simple when they only bear upon one faculty, as anger, which is a simple affection of the faculty of self-de- fence;—compound, when several faculties are concerned at the same time, as shame, which is an affection of the primary faculties of the moral sense and vanity. Gall reproaches the moralists with having multiplied too much the number of primary affective faculties:—in his view, the modifications of a single faculty, and the combination of several, give rise to many sentiments, that are apparently different. For instance, the primary faculty of vanity begets coquetry, emulation, and love of glory. That of self-defence gives rise to temerity, courage, a quarrelling spirit, and fear. Contempt is the product of a combination of the faculties of pride and the moral sense, &c. Lastly; as regards their psychical differences, Gall divides all men into five classes. First. Those in whom all the faculties of humanity predominate; and in whom, consequently, organization renders the developement of the mind and the practice of virtue easy. Secondly. Those in whom the organs of the animal faculties predominate; and who, being less disposed to goodness, need the aid of education and legislation. Thirdly. Those in whom all the faculties are equally energetic, and who may be either worthy, or great criminals, according to the direction they take. Fourthly. Those who, with the rest of the faculties nearly equal and mediocre, may have one predominant. Fifthly, and lastly. Those who have the faculties alike mediocre:— which is the most numerous class. It is rare, however, he remarks, that the characters and actions of men proceed from a single faculty. Most commonly, they are dependent upon the combination of several; and, as the possible combinations of so many faculties are almost innu- merable, the psychical varieties of mankind must be extremely various. Again, as each of the many organs of the brain may have, in different men, a particular degree of developement and activity, seeing that each of the faculties, which are their products, has most commonly a par- ticular shade in every individual; as these organs can establish between each other a great number of combinations; and as men, independ- ently of the differences in their cerebral organization, which give rise to their dispositions, never cultivate and exert their faculties in 'an equal and similar manner, it may be conceived, that nothing ought to be more variable than the intellectual and moral characters of men; and we may thus explain, why there are no two men alike in this respect. Such is a general sketch of the physiological doctrine of Gall, which we may sum up in the language of the author, in his Revue Sommaire, appended to his great work. *' I have established, by a considerable number of proofs, as well negative as positive, and hy the refutation of the most important objections, that the encephalon alone has the 198 SENSIBILITY. immense advantages of being the organ of the mind. Farther researches on the measure of the degree of intelligence of man and animals have shown, that the encephala are more simple or more complex, as their instincts, desires, and faculties are more simple or more compound; that the different regions of the encephalon are concerned in different categories of function; and, finally, that the encephalon of every spe- cies of animal, ahd, consequently, that of man, constitutes an aggrega- tion of as many special organs, as there are essentially different moral qualities and intellectual faculties in the man or animal. The moral and intellectual dispositions are innate. Their manifestation is de- pendent upon organization. The encephalon is the exclusive organ of the mind. Such are four incontestable principles, forming the whole physiology of the encephalon :"—and he adds;—"the detailed develope- ment of the physiology of the encephalon has unveiled the deficiencies of the hypotheses of philosophers regarding the moral and intellectual powers of man; and has been the means of bringing to light a philoso- phy of man, founded on his organization, and, consequently, the only one in harmony with nature."1 It is impossible to enter, at length, into the various facts and hypo- theses developed in the preceding exposition. The great points of doctrine in the system of Gall, are:—First. That the encephalon con- sists of a plurality of organs, each engaged in a separate, distinct office,—the production of a special intellectual or moral faculty. Secondly. That each of these organs ends at the periphery of the ence- phalon ; and is indicated by more or less developement of the part; and Thirdly. That, by observation of the skull, we may be enabled to detect the protuberance, produced by such encephalic developement; and thus indicate the seat of the encephalic organs of the different faculties. It has been shown in the preceding history, that the notion of the plurality of organs has prevailed extensively in all ages; and whatever may be the merit of the arguments adduced by Gall on this subject, it is difficult not to conceive, that different primary faculties may have their corresponding organs. Simple inspection of the ence- phalon indicates that it consists of numerous parts, differing essentially in structure and appearance from each other; and it is but philoso- phical to presume, that these are adapted to equally different functions, although our acquaintance with the physiology of the organs may not be sufficiently extensive to enable us to designate them. Of the in- nate character of several of the faculties described by Gall, it is scarcely possible for us to admit a doubt. Take, for instance, the instincts of generation and of love of progeny. Without the existence of these, every animal species would soon be extinct. It seems fair, then, to presume, that these instincts or innate faculties may have encephalic organs specially concerned in their manifestation. Gall places them in the posterior part of the head,—the instinct of generation in the cerebellum; and his causes for so doing have been cited; yet, striking as his statement in regard to the encephalic seat of the instinct of generation seems to be, it has been contested by many physiologists,— by MM. Broussais, Foville, and Pinel-Grandchamp, Rolando, Flourens, 1 Sur les Fonctions du Cerveau, vi. 500, Paris, 1825. MENTAL FACULTIES—VIEWS OF PHRENOLOGISTS. 199 Desmoulins, Calmeil, and others; and, not only by argument, but by that which must be the test of the validity of the doctrines of the phrenologists,—direct experiment. It has been shown, indeed, that the genital excitement which is supposed by the followers of Gall to be seated in the cerebellum, can be equally produced by irritating the posterior column of the spinal marrow; and it would seem, that coin- cidence of disease of the spinal cord with affection of the genital organs is much more frequent.1 According to Burdach, the propor- tion of cases of disease of the cerebellum, in which there is any mani- fest affection of the sexual organs, is really very small,—not above one in seventeen. Erection has frequently been observed in men after fracture or luxation of the spine; and in hanging, erection and ejaculation of sperm are not uncommon. Dr. Brown Sequard2 affirms, that a transverse section of the cord in the guinea pig always pro- duces erection and ejaculation; and the same occurs when the animal is asphyxiated, or if the cord be galvanized. The results, too, of unprejudiced observation, as to the comparative size of the cerebellum in different animals, are by no means favourable to the phrenological doctrine. There are many highly salacious ani- mals—as the kangaroo, and the monkey—which are not distinguished for unusual size of cerebellum. A strong argument, as before ob- served, in favour of this function of the cerebellum, is founded on the assertion, over and over again repeated, that in animals that have been castrated young, it is much smaller than in the entire male; but the results of the experiments of M. Lassaigne, suggested by M. Leuret,3 are directly opposed to this. These were made on ten stal- lions, of the ages of from nine to seventeen years; on twelve mares, aged from seven to sixteen years; and on twenty-one geldings, aged from seven to seventeen years. The weight of the cerebrum, esti- mating the cerebellum as 1, was thus expressed. Average. Highest. Lowest. Stallions......7-07 7-46 6-25 Mares......6-59 7-00 5-09 Geldings......5-97 7-44 5-16 The average proportional size of the cerebellum in geldings was therefore positively greater than in entire horses and mares. It was also found to be absolutely heavier in the following proportions. Average. Highest. Lowest. Stallions......61 65 56 Mares......61 66 58 Geldings......70 76 64 It would seem, that the dimensions of the cerebrum are usually re- duced by castration;' as in the following table. Average. Greatest. Least. Stallions......433 485 350 Mares......402 432 336 Geldings......419 566 346 1 Muller's Elements of Physiology, by Baly, p. 833, Lond., 1838. 2 Medical Examiner, August, 1852, p. 497. 3 Anat. Compar. du Systeme Nerveux, torn. i. p. 427. 200 SENSIBILITY. These observations are certainly entirely opposed to the statements of the phrenologists; and are more favourable to the idea of the cere- bellum being connected with muscular power. Geldings, as is well known, are employed in active labour; whilst stallions are rarely called upon to exert much effort, being kept especially to propagate their kind. It has been maintained by some physiologists, as by M. Serres, that whilst the hemispheres of the cerebellum are concerned in motion, the central lobe is connected with the instinct of repro- duction. Dr. N. S. Davis1 has, however, shown from positive obser- vation, that no difference can be perceived in the size of either the cerebellar hemispheres or the central lobes in bulls and oxen. It will be obvious, moreover, that if a single case of absence of the cerebellum should be observed in which erotic desires exist; it would be fatal to all these views of the phrenologist. Such cases are rare, but one has been witnessed and recorded by M. Combette,2 and no doubt can exist as to its authenticity. On examining the encephalon of a young girl, who had been addicted to masturbation, a gelatini- form membrane of a semicircular shape, united to the medulla oblon- gata by two membranous and gelatinous peduncles, was observed in place of the cerebellum. The one on the right side had been torn. Near these peduncles, M. Combette found two small masses of white substance, isolated and detached, as it were, of the size of a pea. It is not, therefore, a matter of astonishment, that from an examination of all the evidence adduced on this matter, M. Longet3 should have concluded, that neither pathology, morbid anatomy, comparative ana- tomy nor experimental physiology leads to the admission of the views of the phrenologist in regard to the functions of the cerebellum. It is, moreover, affirmed by Dr. Carpenter4 on the strength of de- cided assertions vr. & Avril, 1842; and Phrenology Examined, translated from the second edition of 1845, by Professor Meigs, Philad., 1846. * Beurtheilung der Phrenologie vom Standpunkte der Anatomie aus., Muller's Archiv., Heft. 3, S. 233, Berlin, 1648. 6 Op citat,, p, 837. 204 SENSIBILITY. quackery of many of the soi-disant phrenologists or craniologists, that has excited the ridicule of those who are opposed to the doctrine of innate faculties, and to the investigation of points connected with the philosophy of the human mind in any other mode than that to which they have been accustomed. Were we, indeed, to concede, that the fundamental principles of craniology are accurate, we might hesitate in adopting the details; and still more in giving any weight to it as a practical science. Gall and Spurzheim would rarely venture to pro- nounce on the psychical aptitudes of individuals from an examination of their skulls; and when they did, they frequently failed. " When Gall," says Dr. Burrows,1 " was in England, he went in company with Dr. H. to visit the studio of the eminent sculptor, Chantry. Mr. C. being at the moment engaged, they amused themselves in viewing the various efforts of his skill. Dr. Gall was requested to say, from the organs exhibited in a certain bust, what was the predominant propen- sity or faculty of the individual. He pronounced the original must be a great poet. His attention was directed to a second bust. He de- clared the latter to be that of a great mathematician: the first was the bust of Troughton, and the second that of Sir Walter Scott!" This kind of hasty judgment from manifestly inadequte data is the every-day practice of the itinerant phrenologist, whose oracular diet a too often draw ridicule not only on the empiric himself, but on a sys- tem which is worthy of a better fate. Ridicule is the harmless but attractive weapon, which has usually been wielded against it; and too often by those who have been ignorant both of its principles and details. It is not above twenty years since one of the most illustrious poets of Great Britain included in his satire the stability of the cow- pox, galvanism, and gas, along with that of the metallic tractors of Perkins— " The cow-pox, tractors, galvanism, and gas, In turns appear to make the vulgar stare Till the swoll'n bubble bursts, and all is air." Byron's " English Bards and Scotch Reviewers." Yet, how secure in its operation, how unrivalled in its results, has vaccination every where exhibited itself! Indiscriminate divination from measurement of heads has been a sad detriment to phrenology as a branch of physiological science; and has been grievously deplored by enlightened phrenologists. " Highly as we estimate the discovery of Gall,"—says one of the ablest of these2— " immense as we regard the advantages which may be ultimately de- rived from phrenology, we confess that we wish to see it less regarded, studied, and pursued as a separate science, and more as a branch of general physiology;" and he adds: "In reviewing the circumstances which have tended to lower phrenology in the estimation of scientific men, and, consequently, to retard both its progress as a science, and the general recognition of its leading truths, we should but very im- perfectly perform our task, if we did not refer, in the strongest possible terms of reproof and condemnation, to the too prevalent proceeding of 1 Commentaries on the Causes, Forms, Symptoms, and Treatment of Insanitv, Lond., 1828. 2 British and Foreign Medical Review, July, 1842. MENTAL FACULTIES — VIEWS OF PHRENOLOGISTS. 205 examinino- living heads in minute detail and indiscriminately, and sup- plying the owners with an account of the -developement,' often on the receipt of a fee, varying in amount, as there is furnished or omitted a general deduction as to the character and probable conduct of the indi- vidual, with or without the ' philosophy,' according to the phraseology of practitioners of this art. We unhesitatingly maintain, that the science is not sufficiently advanced to supply evidence of its truth from every head, or from any one head, and consequently, that such prac- tice as a general one, is so much pure charlatanism. Where any strongly marked peculiarity of individual character exists, its outward sio-n in appropriate subjects, will certainly be detected; but, from the very nature of the thing, these cases must constitute not the rule, but the exception. The practice we condemn, however, makes no distinc- tion of instances. Injudicious zeal, the common ally of ignorance, a wish for effect, not unfrequently more sordid motives, stimulate the self-styled phrenologist in this empirical career; and, as a matter of course, the errors and mistakes perpetually made are constantly ap- pealed to as indicative of the sandy foundations of the entire phreno- logical edifice. We write advisedly in this our unqualified reprobation of the popular custom of 'taking developements.' We believe it to be an extension of the practical application of phrenology much be- yond its legitimate bounds; and we appeal to any one having acquaint- ance with its results, whether any thing like uniformity—the true test of accuracy—is obtained in the majority of cases, even when the most experienced and dexterous pronounce their judgment, if their explora- tions be conducted separately. We ourselves have even witnessed the greatest possible discrepancies. Nay, we have seen the same phreno- logists furnish one character from the head, and a totally different one from the cast, whilst in ignorance of the original of this latter. This we have known to happen, not merely in the practice of one of your shilling-a-head itinerants, but in that of one not unknown to fame in the annals of the science." Such are the views of one, who, unlike the author, expects much from phrenology; and has done much to give it countenance. Yet men will still form their judgments in this manner; and a solitary coincidence, as in all analogous cases, will outweigh a dozen failures.' The doctrine of separate cerebral organs, of the phrenologists, has been for some time in a state of decadency, and has recently lost an able supporter in Dr. Noble, whose work on the " Brain and its Phy- siology" has been, even recently, referred to as one of " the best for the medical student who desires to read the arguments in favour of the system."2 Dr. Noble,3 convinced of the inadequacy of the evidence in its favour, has, in a frank and manly manner, published his recantation, and " influenced by the present advanced state of our knowledge of the brain and nervous system in man, and still more by certain facts in comparative anatomy, has been led to the conclusion that it should at 1 See, on these subjects, the author's Medical Student, second edit., p. 256, Phila- delphia, 1844. 1 Kirkes and Paget, Manual of Physiology, 2d Amer. edit., p. 340 (note\ Philadel- phia, 1853. 3 Elements of Psychological Medicine, p. 45, London, 1853. 206 SENSIBILITY. least be rejected as unproved;" and consequently that he cannot now profess himself to be an adherent "of what is commonly understood by the phrenological system." " Altogether"—he adds—" I feel myself bound to say the organology of Gall's doctrine must be abandoned. Honesty and candour compel me to this admission, though with some reluctance, for it involves the recantation of opinions for many years entertained and avowed."—"I will add a few words concerning the premature success of the phrenological system, and upon the fact of its unmistakable decline in the estimation of our profession. The emi- nently scientific character of many of Gall's researches into the anatomy and physiology of the brain and nervous system, the decidedly phi- losophic spirit displayed in the tone of much that he wrote, and the important additions, which he undoubtedly made to the then current knowledge of the subject of his investigation, were all circumstances accrediting him to the profession as a faithful observer and accurate interpreter of nature. Then, there were the ingenuity and the lucidity of Spurzheim's speculations, and the comprehensive reasonings of Dr. Andrew Combe and Mr. George Combe. There was, moreover, a bold- ness and an earnestness in their arguments, claiming for the phrenolo- gical system an extensive applicability in so many practical relations of life,—arguments which, containing much truth, it would have been very often difficult, without great labour, to confute. All these things constituted obvious reasons why many, in the first instance, accepted phrenology so largely upon trust. When I have had the opportunity of conversing with undoubtedly able men, especially of the medical profession, who avowed their conviction of the truth of phrenology, I have always noticed, that whilst uneducated charlatans recognize no difficulties either in judging of character, or in estimating cerebral developement, they, on the contrary, have constantly spoken with dis- trust of their ability to decide in these respects; showing plainly enough, that their adhesion resulted from the confidence which they have placed in the more prominent apostles and disciples of the sys- tem, rather than from any accurate or careful investigations made by themselves. In my own instance, many circumstances have utterly destroyed my confidence in the observations and the judgment of large numbers of the phrenologists: amongst others, I may adduce the striking fact that the ranks of almost every philosophical folly of the present era, so distinguished in this point of view, have been largely recruited from the expiring phrenological school-teachers and disciples alike. Some have become apostles or partisans of the water-cure; others of clairvoyance and mesmeric prevision; and some, again, of homoeopathy; whilst a few, I believe, have gone over to the spiritual rappers! With the same men, there continues the same turn of mind — the excessive credulity, the readiness to see whatever is looked for, and to wink at, or most elaborately to explain away every thing which makes against the adopted faith; the same bigotry, too, and the same restless spirit of propagandism." " If"—he concludes—" I have dwelt upon this subject at somewhat undue length, it is because I have been anxious to give reasons for the decline of phrenology, both in my own estimation, and in that of others of our profession, who formerly anti- cipated other results." MENTAL FACULTIES—VIEWS OF PHRENOLOGISTS. 207 The doctrine of Gall—which, in its details, has never met with favour from the author—requires repeated unbiassed and careful ex- periments, which it is not easy for every one to institute ; and this is one of the causes why the minds of individuals must long remain in doubt regarding the merits or demerits of the system. From mere metaphysicians, who have not attended to the organization and func- tions of the frame, especially of its encephalic portion, it has ever expe- rienced the greatest hostility; although their conflicting views regard- in o- the intellectual and moral faculties was one of the grounds for the divisions of the phrenologist. It is now, however, we believe, generally admitted by the liberal and scientific, that if we are to obtain a farther knowledge of the mental condition of man, it must be by a combination of sound psychological and physiological observation and deduction. It is time, indeed, that such a union should be effected, and that the undisguised and inveterate hostility, which exists between certain of the professors of these interesting departments of anthropology, should be abolished. " To fulfil, definitely, the object we had proposed to ourselves," says M. Broussais,"1 " we must infer from all the facts and reasoning comprised in this work,—1st. That the explanations of psychologists are romances, which teach us nothing new. 2dly. That they have no means of affording the explanations they promise. 3dly. That they are the dupes of the words they employ in disserting on incomprehensible things. 4thly. That the physiologist alone can speak authoritatively on the origin of our ideas and knowledge; and 5thly. That men, who are strangers to the science of animal organization, should confine themselves to the study of the instinctive and intel- lectual phenomena in their relations with the different social states of existence." This is neither the language nor the spirit that ought to prevail among the promoters of knowledge. Lastly.—Physiologists have inquired, whether there may not be some particular portion of the brain, which holds the rest in subservi- ence ■ some part in which the mind exclusively resides;—for such was probably the meaning of the researches of the older physiologists into the seat of the soul. It is certain, that it is in the encephalon, but not in the whole of it; for the organ may be sliced away, to a certain extent, with impunity. Gall, we have seen, does not admit any central part, which holds the others in subordination. He thinks, that each encephalic organ, in turn, directs the action of the others, according as it is, at the time, in a state of greater excitation. On the other hand, different physiologists admit of a central cerebral part, which they assert to be the seat of the ^vxr{, moi or mind. They differ however, regarding the precise situation of its domicile. At one time, the strange notion prevailed, that the seat of perception is not in the brain, but in its investing membranes. Des Cartes,2 again, embraced the singular hypothesis, that the pineal gland is entitled to this pre-emi- nence. This gland is a small projection, seen in Fig. 189 (vol. i. p. 633), 1 De l'Irritation et de la Folie, Paris, 1828; or Amer. edit, by Dr. T. Cooper, Colum- bia, S. C, 1831. * De Passion. Anim., Amst., 1664, and De Homine, p. 78, Lugd. Bat., 1664. 208 MUSCULAR MOTION. at the posterior part of the third ventricle; and, consequently, at the base of the brain. Being securely lodged, it was conjectured by that philosopher, that it must be inservient to some important purpose; and, upon little better grounds, he supposed that the soul is resident there. The conjecture was considered to be confirmed by the circumstance, that, on examining the encephala of certain idiots, the gland was found to contain a quantity of sabulous matter. This was supposed to be an extraneous substance, which, owing to accident or disease, had lodged in the gland and impeded its functions; and the inference was drawn, that the part, in which such functions were impeded, was the seat of the soul. Nothing, however, is now better established than that the pineal gland of the adult always contains earthy matter.1 Others, again, as Bontekoe,2 La Peyronie,3 and Louis, placed the mind in the corpus callosum; Vieussens in the centrum ovale; Digby4 in the septum lucidum; Drelincourt5 in the cerebellum ; Ackermann in the Sinneshiigel6 (prominence or tubercle of the senses); Som- mering7 in the fluid of the ventricles; and the greater part of phy- siologists in the point where the sensations are received and volition sets out,—the two functions, which, together, form the sensorial power of Dr. Wilson Philip.8 Dr. Darwin9 had previously employed this term in a more extended sense, as including the power of muscu- lar contraction; but in Dr. Philip's acceptation it is restricted to those physiological changes in which the mind is immediately con- cerned.10 The discrepancy among physiologists sufficiently demonstrates, that we have no positive knowledge on the subject. CHAPTEE II. MUSCULAR MOTION, ESPECIALLY LOCOMOTILITY OR VOLUNTARY MOTION. The functions hitherto considered are preliminary to those that have now to attract attention. The former instruct us regarding the bodies that surround us; the latter enable us to act upon them; to execute all the partial movements, that are necessary for nutrition and reproduc- tion ; and to move about from place to place. All these last acts are of 1 Sommering, De Lapillis vel prope vel intra Glandulam Pinealem sitis, Mogunt. 1785. 2 Haller. Bibl. Anat., i. 673. 3 Mem. de l'Academ. des Sciences, Paris, 1741. 4 Of the Nature of Bodies and the Nature of Man's Soul, London, 1658. 5 Opera. Anat., Lugd. Bat., 1684. 6 This term he applies to the optic thalami and corpora striata; because, according to the then received opinion, the optic nerves originate in the optic thalami, and the olfactory nerves from the corpora striata. Gall, Sur les Fonctions du Cerveau ii. 57, Paris, 1825. 7 De Corp. Human. Fabric, iv. § 98. 8 An Experimental Inquiry into the Laws of tbe Vital Functions, p. 186, London, 1817. ' 9 Zoonomia, 3d edit., ii. 103, Lond., 1801. 10 Dr. W. Philip, ibid.; and especially his paper on the Powers of Life, in the Lond. Med. Gazette for March 18 and 25,1837 ; and his Treatise on Protracted Indigestion, &c, Amer. edit., Philad., 1843. See, also, on this subject, Ludwig, Lehrbuch der Physiolo- gic des Menschen, ler Band, S. 452, Heidelberg. 1853. MUSCLES. 209 the same character; they are varieties of muscular contraction; so that sensibility, and voluntary motion or muscular contraction executed by the muscular system of animal life, comprise the whole of the life of relation. M. Magendie includes the voice and movements under the same head; but there is convenience in separating them; and in treat- ing the functions of locomotility and expression distinctly, as has been done by M. Adelon.1 1. ANATOMY OF THE MOTORY APPARATUS. The organs essentially concerned in this function are—the encepha- lon, spinal marrow, nerves, and muscles. The first three of these have been sufficiently described. The last, therefore, will alone engage us. a. Muscles. The muscles constitute the flesh of animals. They are distinguished by their peculiar structure and composition;—being formed of the ele- mentary or primary fibrous tissue, already described. This tissue has the power of contracting, and thus of moving the parts into which it is inserted; hence, muscles have been termed active organs of locomo- tion, in contradistinction to bones, tendons, and ligaments, which are passive. The elementary constituent of the whole muscular system is this primary, fibrous, or muscular tissue, the precise size and intimate texture of which have been the occasion of innumerable researches; and, as most of them have been of a microscopic character, they are highly discrepant, as a brief history will exhibit. Leeuwenhoek2 asserts, that some thousands of the ultimate filaments are required to form the smallest fibre visible to the naked eye. He describes these fibres as serpentine and cylindrical; and affirms, that they lie parallel to each other, and are of the same shape in all animals, but differ greatly in size. Their size, however, bears no proportion to that of the animal to which they belong. Muys3 affirmed, that every apparent fibre is composed of three kinds of fibrils, each progressively smaller than the other; and that those of the medium size, although not larger than the ninth part of a very delicate hair, are composed of one hundred filaments. He supposed the ultimate filament to be always of the same size. Prochaska" says, that the ultimate fibre or filament is discernible, and that its thickness is about the ^th part of the dia- meter of the red globules of the blood; and MM. PreVost and Dumas,5 from the result of their microscopic observations, affirm that 16,000 fibres may be contained in a cylindrical nerve, one millimeter or 0*039 of an inch in diameter. The microscopic examinations of Mr. Skey,6 which have been confirmed and developed by subsequent observers, led him to infer, that there is a distinction between the muscular fibres of 1 Physiologie de l'Homme, 2de edit., ii. 1 and 204, Paris, 1829. 8 Arcana Naturae, p. 43. 3 Investigate Fabricse qua? in Partibus Musculos Componentibus exstat,p. 274, Lugd. Bat., 1841. 4 De Carne Musculari, p. 25, Vienn., 1778. 6 Annales de Chimie, torn, xviii.; Magendie's Journal de Physiologie, torn. iii. 6 Transactions of the Royal Society, for 1836. VOL. II.—14: 210 MUSCULAR MOTION. lib I Fig. 332. animal and of organic life; the former having, in man, an average diameter of 4 o^th of an inch. Each of these muscular fibres is divisible into bands or fibrillse, and each of these is again subdivisible into about 100 tubular filaments, arranged parallel to each other: the diameter of each filament is yg^^th part of an inch, or about a third part of that of a blood-globule. The muscles of organic life he found to be com- posed, not of fibres similar to those described, but of filaments only; these filaments being interwoven, and forming a kind of untraceable network. The fibres of the heart appeared to possess a somewhat compound character of texture: the muscles of the pharynx exhibited the character of those of animal life, whilst those of the oesophagus, stomach, intestines, and arterial system possessed the character of those of organic life. He was unable to deter- mine the exact nature of the muscular fibres of the iris. At the present day, muscular tissue is universally divided into two kinds;—the one forming the muscles of animal life, and the other the muscles of organic life. The former, called also striated and striped muscles (see Fig. 335), embrace all the voluntary muscles, as well as the heart, the muscular tissue of the pharynx and upper portion of the oesophagus: the latter, called also non-striated or unstriped muscles, con- stitute the proper contractile coats of the di- gestive tube from the middle of the oesophagus to the external sphincter ani, as well as those of the urinary bladder, trachea and bronchia, excretory ducts, gall bladder, vesiculse semi- nales, pregnant uterus and Fallopian tubes; arteries, and—to a less degree—of the veins. The intimate structure of the filaments has given rise to extraordinary contrariety of sen- timent;—some, as Santorini, Heister, Cow- per,1 Vieussens, Mascagni,2 Prochaska,3Borelli,4 John Bernouilli, &c, believing them to be hol- low; others, as Sir A. Carlisle,5 and Fontana,6 some thinking them straight; others zigzag, spiral, or waved; Non-striated Muscular Fibre. At b, in its natural state. At a, showing the nuclei after the action of acetic acid. Fig. 333. Non-striated Muscular Fibre. 4. Muscular fibre of organic life, with two of its nuclei; taken from the urinary bladder, and magni- fied 600 diameters. 5. Muscular fibre of organic life from the sto- mach, magnified the same. solid: some jointed; others knotted, &c. &c.7 Borelli and J. Bernouilli an- nounced, that each fibre consists of a series of hollow vesicles, filled with a kind of spongy substance or marrow;—the shape of the vesicles 1 Myotomia Reformata, Lond., 1724. s Oper. Minor., pt. i. p. 98. * De Motu Animalium; addit. Johan. Bernouilli, M. D Musculorum, Lu<:d. Bat., 1710. 5 Phil. Trans, for 1805, p. 6. 7 Elliotson's Physiology, p. 476. 2 Prodromo, p. 97. , Meditationes Mathematic. B Sur les Poisons, ii. 228. MUSCLES. 211 being, according to the former, rhomboidal,—according to the latter, spheroidal. Deidier conceived it to be a fasciculus, composed of an artery, vein, and lymphatic, enveloped by a nervous membrane, and held together by nervous filaments:—Prochaska, to consist of bloodves- sels turned spirally around an axis of gelatinous or fibrinous substance, into the interior of which the blood rushes at the time of contraction. He says, that the visible fibres are not cylindrical, as they had been described by many observers, but of a polyhedral shape; and that they are generally flattened, or thicker in one direction than in the other. All are not of the same diameter : they differ in different ani- mals, and in different parts of the same animal; and are smaller in young subjects. The filaments or ultimate fibres, twhich can only be seen with the microscope, have the same shape as the visible fibres: they are, however, always of the same magnitude. Sir A. Carlisle,1— whose opinions, on many subjects at least, are not entitled to much weight,—describes the ultimate fibre as a solid cylinder, the covering of which is a reticular membrane, and the contained part a pulpy sub- stance, regularly granulated, and of very little cohesive power when dead. The extreme branches of the bloodvessels and nerves, he says, are seen ramifying on the surface of the membrane enclosing the pulp, but cannot be traced into the substance of the fibre. Mr. Bauer2 and MM.Prevost and Dumas3 differed essentially from the observers already mentioned. Mr. Bauer found, that the muscular fibre was composed of a series of globules, arranged in straight lines; the size of the globule being s^o-th part of an inch in diameter; whilst M. Raspail4 considers, that the intimate structure of the muscular tissue, when it is in its most simple state, consists of a bundle of cylinders, intimately agglutinated together, and disposed, in a very loose spiral form, around the ideal axis of the group. These tubes are filled with a substance not wholly miscible with water, and may be regarded as elongated vesicles, united at each end to other vesicles of a similar character. When a muscular fibre is seen through an ordinary microscope, it Fig- 334. appears to be composed of longitu- dinal filaments, each consisting of a string of globules, about so^th of an inch in diameter. "But with a better instrument," says Mr. Mayo,5 "such as that which Mr. Lister pos- sesses, the delusion vanishes, and the parallel lines, which traverse the fibre, appear perfectly clean and even. Mr. Lister politely gave me an opportu- „,.,,., , „, •. A J . G. , . rr Striated Muscular Fibres. nity of examining this appearance, 1 ■ i -,. °-i1 t ■ i c 1 A. A small portion of muscle, natural WillCn Was diSCOVered by himself and size. B. The same magnified 5 diameters, Fir TTr>rlrrb-'n " °^ larger and smaller fasciculi, seen in a Ui. XlOUgKin. transverse section. ' Op. citat. 2 Sir E. Home, Lectures on Comp. Anat., v. 240, Lond., 1828. 3 Appendix to Edwards, De i'lniiuence des Agens Physiques sur la Vie, Paris, 1824. 4 Chimie Organique, &c, p. 211, Paris, 1833. 5 Outlines of Human Physiology, chap. iii. 3d edit., London, 1833. 212 MUSCULAR MOTION. The researches of Mr. Bowman1 and others are as follows. When the smallest fibre, that can be seen by the naked eye, is examined by the microscope, it is found to consist of a number of cylindrical fibres lying parallel to each other, and closely bound together. These fibres present striae—one set of which is longitudinal, the other transverse. When the fibres are separated from each other, and ex- amined more closely, they may be resolved into fibrilloe, which, so far as at present known, are the ultimate ele- ments of muscular structure. They are represented in Figure 341. The fibrillae are bound together by a deli- cate tubular sheath or sarcolemma, which may be distinctly seen, when the two ends of a fibre are drawn apart. The contained fibrillae will rupture, whilst the sheath remains en- tire, as represented in Fig. 336. During the act of contraction, it is also some- times observed to rise up in wrinkles, upon the surface of the fibre, as in Fig. 353. It is distinct from the cel- lular tissue that binds the fibres into fasciculi; does not appear to be perforated by nerves or capillary vessels; and evidently has no share in the contraction of the fibre. Although commonly described as cylindrical, these fibres would seem to be rather of a polygonal form, their sides being flattened against those of the adjoining fibres. Their size varies greatly in different classes of animals, and even in the same animal, and the same muscle, Mr. Bowman found them to be, in the human male, from to TA5 of an inch: in the female, Striated Muscular Fibres. A few muscular fibres, being part of a amall fasciculus, highly magnified, showing the transverse striae, a. End view of 6 b, fibres; c. A fibre split into its fibrillae. Fig. 336. Fragments of an Elementary Fibre of the Skate, held together by the un- torn but twisted Sarcolemma. "507 from So-5 to ,|?, and it has been esti- may be corn- mated, that each fibre posed of from 500 to 800 fibrillae. Il- lustration, Fig. 337, representing a transverse section of the fibres from the pectoral muscle of a teal; and Fig. 338, a transverse section of the ultimate fibres of the biceps, exhibit well the irregular shape and size, and the cut extremities of fibrils that go to the constitution of the fibre. Under the microscope each fibre exhibits a close alter- nation of light and dark lines crossing it transversely, which are pre- sumed to be owing to the arrangement of beaded fibrilla3, as shown in Fig. 339. The beaded enlargements of the fibrillar seem to adhere 1 Philosophical Transactions for 1840 ; art. Muscle, Cyclop, of Anat. and Physiol., Part xxiv., p. 507, July, 1842; and Todd and Bowman's Physiological Anatomy and Physiology of Man, Part i., Lond., 1843. MUSCLES. 213 closely to each other, so that when the extremities of a fibre are drawn apart, it not unfrequently happens, that the disks formed by them separate. It has been affirmed, Fig. 337. that the primitive com- ponent segments of the fibrillae are the ulti- mate elements of the fibre; these segments being connected longi- tudinally, so as to con- stitute the fibrillae, the distinctness of which is marked, even in the complete fibre, by lon- gitudinal striae; whilst they also adhere late- rally, so as to form disks, the partial sepa- ration of which gives origin to the trans- verse striae. The views of histo- logists on the whole of this subject have until of late years been suffi- ciently discrepant. Dr. Martin Barry1 revived a view of Dollinger, but which has met with little favour, and certainly needs demonstration, that the blood corpuscle is the immediate agent in the construction of many tissues, particu- larly the muscular, the elementary fibre of which—called by him spiral fibre—may even be detected in the nucleus of the cor- puscle. Mr. Bowman2 has affirmed, that the muscular fibre always presents, upon and within it, longitudinal dark lines, along which it will generally split up into fibrillar, but it is by a fracture alone, that the fibrillae are obtained. They do not exist as such in the fibre. He farther observed, that it occasionally happens that no disposition whatever is shown to this longitudinal cleavage; but that, on the contrary, violence causes a separation along the transverse dark lines, which always intersect the fibre in a plane perpendicular to its axis. By such a cleavage, disks and not fibrillae are obtained; and this cleavage is as material as, although less fre- quent than, the former. Hence, he esteems it as proper to say, that the fibre is a pile of disks, as that it is a bundle of fibrillae; that it is, in fact, neither one nor the other; but a mass in the structure of which 1 Philosophical Transactions, for 1842, Part i. p. 89. 2 Art. Muscle, Cyclopaedia of Anat. and Physiology, July, 1842, p. 508, and Physio- logical Anatomy and Physiology of Man, Part i., Lond., 1843. Transverse Section of Fibres from the Pectoral Muscle of a Teal. Fig. 338. Transverse Section of Ultimate Fi- bres of Biceps. 214 MUSCULAR MOTION". there is an intimation of the existence of both, and a tendency to cleave in the two directions. If there were a general disintegration Fig. 339. Fie;. 340. Fragment of Muscular Fibre from macerated heart of Ox, showing formation of striae by aggregation of beaded fibrillae. Portion of Human Muscular Fibre, separating into disks, by cleavage in direction of transverse striae. along all the lines in both directions, there would result a series of particles, which might be termed primitive particles or sarcous elements, the union of which would FiS- 341- constitute the mass of the fibre; these elementary par- ticles being arranged and united together in the two directions. Gerber1 is disposed to con- sider, that the " cross-streak- ing" frequently depends on the presence of a wrinkled fascicular sheath; "for when," he says, "the more superfi- cial fibres chance to be re- Fragments of Striated Elementary Fibres, showing a moved, and the deeper Ones Cleavage in Opposite Directions.—Magnified 300 exposed, these appear Cylin- l^giTukal cleavage. The longitudinal and trans- drica}> and th(3 bundle at the verse lines both seen. Some longitudinal lines darker and part is lonSfitudmallv Streak- wider than the rest, and not continuous from end to end: -i « i "• p this results from partial separation of the fibrilla. 6. Fi- ed. At the extremity 01 a brillas, separated from one another by violence at the f^,™ -Pctanin 1 + n +Tho r»o broken end of the fibre, and marked by transverse lines uOm iaSClCUlUS, tOO, Xne pe- equal in width to those on the fibre. 7, 8 represent two -rir\Vio-nal -fiK-noa nAon annear appearances commonly presented by the separated single rlPrlfra1 UOreS Olien appear fibrillse. (More highly magnified.) At 7, the borders and SO distinctly marked off from transverse lines are all perfectly rectilinear, and the in- -, • i j i eluded spaces perfectly rectangular. At 8, the borders are the internal and more pulpy scalloped, the spaces bead-like. When most distinct atad definite, the fibrilla presents the former of these appear- ances.—2. Transverse cleavage. The longitudinal lines are scarcely visible. 3. Incomplete fracture following the opposite surfaces of a disk, which stretches across the in- terval and retains the two fragments in connexion. The edge and surface of this disk are seen to be minutely granu- lar, the granules corresponding in size to the thickness of the disk, and to the distance between the faint longitudinal lines. 4. Another disk nearly detached. 5. Detached disk more highly magnified, showing the sarcous elements. vations, that the transverse striae seem to be produced by a delicate thread of areolar tissue 1 Elements of General and Minute Anatomy, by Gulliver, p. 251. 2 Wilson's Anatomist's Vade Mecum, by Goddard, Amer. edit., p. 142, Philad., 1843. substance, that the existence of a more compact trans- versely streaked sheath can scarcely be called in ques- tion." Dr. Goddard2 is of opinion, from his own obser- MUSCLES. 215 wound spirally around the ultimate fibrils, so as to hold them in a bundle; whilst Dr. Will1 thinks that they are owing to the fibrils, which, in their natural relaxed state, are uniform and cylindrical, being thrown in contraction into undulations or zigzag flexures; and Va- lentin,2 who has long described the relaxed muscular fibre as a uniform cylinder, confirms, generally, Dr. Will's account, although he cannot determine, whether the striated appearance of the fibrils be owing to their becoming varicose, or to zigzag flexures induced by contraction. He also maintains the view, long professed by him, that the fibres and fasciculi in the fully contracted state, are bent in zigzag lines, with angles of from 80° to 120°. The zigzag arrangement of fibres having the appearance of " series of rhomboidal pinnulae, which immediately disappear as soon as the muscle ceases to act," was observed by Hales,3 in the abdominal muscles of the frog. Mr. Erasmus Wilson,4 by resorting to peculiar methods'of manipu- lation, and employing a microscope of more than ordinary power, believes that he has succeeded in discovering the real structure of the ultimate muscular fibril in a specimen taken from the arm of a strong healthy man immediately after amputation. He finds each fibril to be composed of minute cells disposed in a linear series, flattened at their surfaces of apposition, and so compressed in the longitudinal direction as to have no marginal indentation on the surface; thus constituting a uniform cylinder divided into minute subdivisions by transverse septa, which are formed by the adherent surfaces of contiguous cells. The diameter of the fibril, in the state of relaxation, is the 20,000th part of an inch. The cells are filled with a transparent substance, to which Mr. Wilson gives the name myoline, and which differs in its re- fractive density in different cells. In four consecu- tive cells, the myoline is of greater density than in the four succeeding cells, and this alternation is repeated throughout the whole course of the fibril. In consequence of all the fibrils composing the ulti- mate fasciculus having the same structure; and the cells, which are in lateral juxtaposition, containing myoline of the same density, they act similarly on light, and the whole presents to the eye of the mi- croscopic observer a succession of striae or bands, dark and luminous alternately, and transverse to the direction of the fasciculus; an appearance which has been noticed by previous observers, but the cause of which, according to Mr. Wilson, had not been before ascertained. A dark stria may occasionally appear as a luminous one, and conversely, when viewed by light transmitted at different degrees of obliquity. The structure here described, Mr. Wilson remarks, reduces the muscular fibre to the simple type of organization exhibited in the combination Fig. 342. i \\ \% t?1 Mass of Ultimate Fibres from the Pectoralis Major of the Human Foetus, at nine months. These fibres have been immersed in a solution of tartaric acid; and their "numerous cor- puscles, turned in va- rious directions, some presenting nucleoli," are shown. 1 Muller's Archiv., 1843, Heft iv. 2 Lehrhuch der Physiologie des Menschen, ii. 33, Braunschweig, 1844. 3 Statical Essays, ii. 61, Lond., 1733. * Proceedings of the Royal Society, June 20, 1844. 216 MUSCULAR MOTION. 343. of a series of cells, associating it with other tissues of cell formation; and may probably, he thinks, open new sources of explanation of the immediate agency of muscular action,—a power which, as he properly observes, is in- volved in the deepest mystery. One of the most recent of the views that have been published, is that of Dr. Sharpey1 and Dr. Carpenter,2 announced about the same time; according to which, each of the alternate light and dark particles of which the fibril is com- posed, has a quadrilateral and generally a rec- tangular form. Each bright particle or space is marked across its centre by a fine, dark, transverse line or shadow, by which the space is divided into two equal parts; and, at times, a bright border is perceptible on either side of the fibril, so that each of the rectangular dark bodies seems to be surrounded by a bright area, having a similar quadrangular outline, as if the pellucid substance inclosed it on all sides;— appearances which have been considered to show, that the elementary particles of which the fibril is composed are little masses of pel- lucid substance, possibly nucleated cells, pre- senting a rectangular outline, and appearing dark in the centre. The ultimate fibres or filaments, when united in bundles, form fas- ciculi or lacerti; and these, by their aggregation, constitute the various muscles. Each fibre, each lacertus, and each muscle, is surrounded by a sheath of areolar tissue, which enables them to move readily upon Muscular Fibrils of the Pig. a. An apparently single fibril. b. Longitudinal segment of a fibre consisting of a number of fibrils connected together. c. Other smaller collections of fibrils.—Magnified 720 diameters. Fig. 344. Attachment of Tendon to Muscular Fibre, in Skate. each other, and preserves them in situ. The fibres are not the same at the extremities as they are at the middle. The latter only consist of the proper muscular tissue; the extremities being formed of areolar tissue. If we examine a muscle, we find that the proper muscular fibres become gradually fewer, and at length cease to be perceptible as 1 Human Anatomy, by Jones Quain, M. D., edited by Quain and Sharpey, Amer. edit., by Leidy, i. 316, Philad., 1849. ' Elements of Physiology, Amer. edit., p. 208, Philad., 1846. MUSCLES. 217 they approach the tendon at one or other extremity. In this way, the fibro-areolar membrane, which surrounds every fibre, becomes freed from the muscular tissue; its divisions approximate, and become closely united and condensed, so as to form the cord or tendon, which, of course, holds a relation to each fibre of the muscle; and when they all con- tract, the whole force is exerted upon it. The microscopic observa- tions of Mr. Bowman exhibited to him, that the component fibres of the tendinous structure are arranged with great regularity, parallel to each other, and are attached to the end of the sarcolemma, which ter- minates abruptly, as in Figs. 336 and 344; which shows the attach- ment of the tendon to the muscular fibre in the skate. Dr. Leidy1 observed that the filaments of areolar tissue, which "form the sheaths of the muscular fasciculi, proceed, for the most part, in a diagonally crossing manne^ around the fasciculi, occasionally passing in between the fibres and intermingling with fine filaments of elastic tissue which exist in this situation. The sheaths are also connected together by filaments from them, which pursue the same diagonally crossing course. The filaments of the fibro-areolar sheaths become more or less straight at the extremities of the muscular fasciculi, and combine with the fibrous filaments originating there to form the tendinous connexion of the muscle. The close union that exists between the muscle and its tendon for- merly gave occasion to the belief, that the latter is only the former con- densed. An examination of some of the physical and vital properties of the two will show, that they differ as essentially as any two of the constituents of the body that could be selected. The tendon consists chiefly of gelatin and albumen, and does not exhibit the same irrita- bility; whilst the muscle is formed essentially of fibrin; and contracts under the will, as well as on the application of certain mechanical and chemical irritants. The differences, in short, that exist between the two, are such as distinguish the primary fibrous and areolar tissues; yet the opinion of their identity prevailed in antiquity; was embraced by Boerhaave and^his school, and, as Dr. Bostock2 observes, was so generally admitted even in the middle of the last century, that Haller3 and Sabatier4 scarcely ventured to give a decided opposition to it. Similar remarks are applicable to the notion of Dr. Cullen,5 that muscles are only the moving extremities of nerves. The fibres of the muscle were supposed by him to be continuous with those of the nerve; to be, indeed, the same substance, but changed in structure; so that when the nerve is converted into muscle, it loses the power of com- municating feeling, and acquires that of producing motion. Every muscle and every fibre of a muscle is probably supplied with bloodvessels, lymphatics, and nerves. These cannot be traced into the ultimate filament; but, as this must be possessed of life and be con- 1 Proceedings of the Academy of Natural Sciences of Philadelphia, vol. iv., No. 6, 1848; and Quain's Anatomy, by Quain and Sharpey, Amer. edit., by Leidy, i. 319, Philadelphia, 1849. 2 An Elementary System of Physiology, 3d edit., p. 84, London, 1836. 3 Element. Physiol., ii. 1, 18. 4 Traite complet d'Anatomie, i. 242, Paris, 1791. 5 Institutions of Medicine, §§ 29, 94; or Works of William Cullen, M. D., by John Thompson, M. D., i. pp. 15, 68, Edinb. and Lond., 1827. 218 MUSCULAR MOTION. Fig. 345. tractile under the will, it must receive through the bloodvessels and nerves the appropriate influences. MM. Dumas and Prevost,1 and Mr. Bowman,—as has been remarked, — affirm, that the microscope shows, that neither the one nor the other terminates in the muscle. The vessels merely traverse the organs;—the arteries terminating in corresponding veins; so that Capillary Network of Muscle. the nutrition of muscles is effected by the transudation of plastic materials through the parietes of the artery, in the same manner as other parts are nourished. A similar distribution is assigned by them to the nerves. All the branches, they assert, enter the muscle in a direction perpen- dicular to that of the fibres composing it; and their final ramifications, instead of terminating in the muscular fibres, surround them loopwise, and return to the trunk that furnished them, or anastomose with some neighbouring trunk. In their view, each nervous filament, distributed to a muscle, sets out from the anterior column of the spinal marrow, forming part of a nervous trunk; turns around one or more muscular fibres, and returns along the same or a neighbouring trunk to the pos- terior column of the marrow. The red colour of muscles is usually ascribed to the blood distributed to them, as it may be removed by repeated washing and maceration in water or alcohol, without the texture of the muscle being modified. By some, it has been thought, that a quantity of red blood remains attached to the fibres, and is extravasated from the vessel; by others, it is presumed, with more probability, to be contained in the vessels, and according to Mulder,2 who considers the red colour to be wholly due to the blood in the capillary system of the muscles, when they are in- jected with water, every muscle is colourless. Bichat3 conceived, that the colour is dependent upon some foreign substance combined with the fibre; and he grounded his opinion upon the circumstance that, in the same animal, some of the muscles are always much redder than others, and yet they do not appear to have a greater quantity of blood sent to them ; and also, that in different classes of animals the colour of the muscles does not appear to correspond with the quantity of red blood circulating through their vessels. The fact, however, that when muscles have been long in a state of inaction they become pale; and that, on the other hand, the colour becomes deeper when they are exer- cised, is additional evidence, that their colour is dependent upon the blood they receive, which is found to diminish or increase in quantity, according to the degree of inactivity or exertion. Muscles differ, like the primary fibre, at their extremities and centre; the former being composed of condensed fibro-areolar membrane; the latter of the muscular or fibrous tissue. The centre of a muscle is usually 1 Magendie's Journal de Physiologie, torn. iii. 2 The Chemistry of Vegetable and Animal Physiology, translated by Fromberg, &c. p. 589, Edinburgh and Lond., 1849. 3 Anat. General., ii. 327, Paris, 1818. MUSCLES. 219 called its venter or belly ; and the areolar texture at the extremities is variously termed;—that from which it appears to arise being called the head or origin; and that into which it is inserted the tail, termination or insertion. These terms are not sufficiently discriminative. We shall find, that a muscle is capable of acting in both directions; so that the head and the tail—the origin and insertion—may reciprocally change places. In ordinary language, however, the extremity at which the albugineous tissue (if we adopt Chaussier's nomenclature), assumes a rounded form, so as to constitute a cord or tendon, is called the inser- tion. AVhen this tissue is expanded into a membrane it is termed an aponeurosis; and in this state it exists at the head or origin of the muscle; so that by tendon and aponeurosis the muscles are inserted into the parts, which they are destined to move, if we exceptifthose that are inserted into the skin. Fig. 346. Compound Ventriform Muscle. Muscles are divided into simple and compound. The simple are those whose fibres have a similar course and arrange- Fig. 347. ment. They may be either flat or ventriform, radiated or penniform. The compound arise from different parts: their origins are, conse- quently, by distinct fasci- culi, or they may terminate by distinct insertions. Fig. 346, which is a representa- tion of the biceps—a flexor muscle of the forearm—is one of these. It has, as its name imports, two heads running into one belly. It is, also, an ex ample of a ventriform muscle. In the pectoralis major, Fig. 347, we have an example of the radi ated muscle, or of one in which the fibres converge toward their tendi nous insertion. Penniform Muscle. Fig. 348. ^SSSSS Double Penniform Muscle. In the penniform muscle, the fibres run in a parallel direction, but are all inserted obliquely into the tendon, like the feathers of a quill. Fig. 34b is a representation of a double penniform muscle. Muscles 220 MUSCULAR MOTION. may, also, be complicated: that is, with one belly, and several tendons having the fibres variously inserted into them; or having several bellies with the tendons interlaced. They are, again, partitioned into the long, broad, and short. The long muscles are situate chiefly on the limbs, and are concerned in locomotion. The broad generally form the parietes of cavities: they are not so much enveloped as the long by strong fibrous aponeuroses or fasciae, owing to their being obviously less liable to displacement; and the short are situate in parts, where considerable force is required, and but little motion; so that their fibres are very numerous. The number of muscles varies, of course, in different animals, in proportion to the extent and variety of motion they are called upon to execute. In man, it is differently estimated by anatomists; some describing several distinct muscles under one name; and others di- viding into many what ought to belong to one. According to the arrangement of M. Chaussier, three hundred and sixty-eight distinct muscles are admitted; but others reckon as many as four hundred and fifty. When muscles are subjected to analysis, they are found to consist of fibrin (syntonin); osmazome; jelly; albumen; phosphates of soda, ammonia, and lime; carbonate of lime; chloride of sodium; phos- phate, and lactate of soda; and, according to Fourcroy and Vauque- lin,1 sulphur and potassa are present. The great constituents of the pure muscular tissue are,—fibrin, and probably osmazome;—the gelatin met with being ascribable to the areolar membrane that enve- lopes the muscular fibres and lacerti. The membranous structures of young animals contain a much greater quantity of jelly than those of the adult; and it is probably on this account, that the flesh of the former is more gelatinous; not because the muscular fibre contains more gelatin. M. Thenard assigns the muscles, on final analysis, the following constituents:—fibrin; albumen; osmazome; fat; substances capable of passing to the state of gelatin; acid (lactic), and different salts: kreatin and kreatinin have likewise been found in them. They have also been analyzed by Berzelius and Braconnot2 and others. It must be borne in mind, however, as M. Easpail3 has properly re- marked, that all these are the results of the analysis of muscle, as we meet with it. The analysis of muscular fibre has yet to be accom- plished. In this, too, and every analogous case, the analysis only affords us evidence of the constituents of dead animal matter; and some of the products may even have been formed by new affinities resulting from the operations of the analyst. They can afford but an imperfect judgment of the constitution of the living substance. These remarks are especially applicable to the efforts at determining the composition of muscle by ultimate analysis. Mulder,4 indeed, affirms, that this is impracticable—" for in this process we burn a mixture of 1 Annales de Chimie, lvi. 43. 2 Muller's Handbuch der Physiologie, Baly's translation, Part i. p. 369, Lond., 1837; and Dr. T. Thomson, Chemistry of Animal Bodies, p. 273, Edinb.. 1843. 3 Op. citat., p. 214. 4 The Chemistry of Vegetable and Animal Physiology, by Fromberg, &c, p. 589, Edinb. and Lond., 1849. 5> ' * CHEMICAL COMPOSITION OF MUSCLES. 221 various substances, a very complicated tissue of muscular fibres, liga- mentary tissue, coats of bloodvessels and nerves. If, therefore, Play- fair and Bockmann have found the composition of muscle to be iden- tical with that of blood,—which is a mixture of various substances, containing some that are entirely different from those of muscle, and in which again others are wanting that are present in the latter,—then this may be considered as a proof that it is impossible to find out essential differences by means of ultimate analysis:"—and he adds— "Nothing has ever surprised me more than the assertions now so fre- quently repeated, that muscle and blood are identical in composition,— two substances which present, in fact, no other point of resemblance, except this, that they both contain protein compounds. But if we proceeded upon this principle, we should be induced at present to apply the term identity to a great number of substances indeed." Muscular structure is liable, under particular circumstances, to a singular kind of conversion, to which it may be well to advert. When, about the latter part of the last century, it was determined, for pur- poses of salubrity, to remove the bodies from the churchyard of Les Innocens at Paris'—which.had been the cemetery for a considerable part of the population of Taris for centuries, the whole area, occupy- ing about seven thousand square yards, was found converted into a mass, consisting chiefly of animal manner, and raising the soil several feet above the natural level. On opening the ground, to remove the prodigious collection of dead bodies, they proved to be strangely al- tered in their nature and appearance. What had constituted the soft parts of the body was converted into an unctuous matter, of a gray colour, and peculiar, but not highly offensive, smell. According to their position in the pits,—for the bodies were deposited in pits or trenches, about thirty feet deep, each capable of holding from twelve hundred to fifteen hundred,—and according to the length of time they had been deposited, this transformation had occurred to a greater or less extent. It was found to be most complete in those that were nearest the centre of the pits, and when they had been buried about three years. In such case, every part, except the bones, hair and nails, seemed to have lost its properties, and to be converted into gras des cimetieres, which was found to be a saponaceous compound, consisting of ammonia, united to adipocire,—a substance, as its name imports, possessing properties intermediate between those of fat and wax. When the adipocire was freed from the ammonia, and obtained in a state of purity, it was found to resemble strongly spermaceti, both in physical and chemical qualities. It was afterwards discovered, that the conversion of muscular flesh into adipocire might be caused by other means. Simple immersion in cold water, especially in a running stream, was found by Dr. Gibbes2 to produce the conversion more speedily than inhumation. It can be caused, too, still more rapidly by the action of dilute nitric acid. The chemical is not the only interest attached to this substance. It has been adduced in a court of justice for the purpose of enabling 1 Thouret, Journal de Physique, xxxviii. 255. 2 Philosophical Transactions for 1794 and 1795. 222 MUSCULAR MOTION. some judgment to be formed regarding the time that a body may have been immersed in the water. It is probable that this must differ greatly according to various circumstances;—as the period that elapsed between the death of the individual, and the act of immersion; the conditions of the fluid as to rest or motion, temperature, &c.; and the temperature of the atmosphere; so that any effort to fix a time for such conversion must be liable to much in conclusiveness. Yet the opinion of a medical practitioner on the subject has been the founda- tion of a juridical decision. At the Lent assizes, holden at Warwick England, in the year 1805, the following case came before the court. A gentleman, who was insolvent, left his home with the intention,— as was presumed from his previous conduct and conversation,—of de- stroying himself. Five weeks and four days after that period, his body was found floating down a river. The face was disfigured by putrefac- tion, and the hair separated from the scalp on the slightest pull; but the other parts of the body were firm and white, without any putrefac- tive appearance. On examining the body, it was found that several parts were converted into adipocire. A commission of bankruptcy having been taken out against the deceased a few days after he left home, it became an important question to the interest of his family to ascertain whether or not he was living at that period. From the changes sustained by the body, it was presumed, that he had drowned himself on the day he left home; and to corroborate the presumption, the evidence of Dr. Gibbes was requested, who, from his experiments on this subject, it was thought, was better acquainted with it than any other person. Dr. Gibbes stated on the trial, that he had procured a small quantity of this fatty matter, by immersing muscular parts of animals in water for a month, and that it required five or six weeks to form it in any large quantity. Upon this evidence, the jury were of opinion, that the deceased was not alive at the time the commission was taken out, and the bankruptcy was accordingly superseded I1 b. Bones. The bones are the hardest parts of the animal frame; and serve as a base of support and attachment to the soft parts. They constitute the framework of the body, and determine its general shape. The principal functions they fulfil are,—to form defensive cavities for the most important organs of the body,—the encephalon, spinal-marrow, &c.—and to act as so many levers for transmitting the weight of the body to the soil, and for the different locomotive and partial movements. To them are attached the different muscles, concerned in those func- tions. In man and the higher classes of animals, the bones are, as a general rule, within the body; his skeleton is, consequently, said to be internal. In the Crustacea, the testaceous mollusca, and certain in- sects the skeleton is external; the whole of the soft parts beino- con- tained within it. The lobster and crab are familiar instances of this arrangement. The stature of the human skeleton is various, and may be taken, on 1 Male, Epitome of Forensic Medicine, in Cooper's Tracts on Medical Jurisprudence, Philad., 1819. r BONES. 223 the average, perhaps,—in those of European descent,—at about five feet seven and a half inches.1 We find, however, examples of con- siderable variation from this average. A skeleton of an Irish giant, in the museum of the Eoyal College of Surgeons of London, measures eight feet four inches. On the other hand, Bebe, the dwarf of Stanislaus, King of Poland, was only thirty-three inches high; and a Polish noble- man, Boruwlaski, is said to have measured twenty-eight French inches, at twenty-two years of age. Mr. Mathews, the comedian, states, how- ever, that he measured him late in life and found that his height was three feet three inches; and that he had undoubtedly grown an inch a short time before he was eighty-one, when he measured three feet four.2 He had a sister, whose height was twenty-one inches.3 Sir George Simpson,4 in one of the villages of Siberia, saw a dwarf, about forty vears of age, thickset, with a large head, and barely two feet and a half high. " For his inches, however," says Sir George, " he was a person of great importance, being the wise man of the place, and the great ar- biter in all disputes, whether of love or of business." The celebrated dwarf, called General Tom Thumb, was seen by the author in 1847. He was then said to be fifteen years old; weighed at the Mint twenty pounds and two ounces, and was twenty-eight inches high. His intel- lect was evidently limited, childlike. The bones may be divided into short, broad or flat, and long. Short bones are met with in parts of the body, which require to be both solid and movable:—in the hands and feet, for example; and in the spine. Flat or broad bones form the parietes of cavities, and aid materially in the movements and attitudes, by affording an extensive surface for the attachment of muscle. •: Long bones are chiefly intended for locomotion; and are met with only in the extremities. The shape of the body or shaft and of the extremities of a bone merits attention. The shaft or middle portion is the smallest in diameter, and is usually cylindrical. The extremities, on the other hand, are expanded; a circumstance, which not only adds to the solidity of the articulations, but diminishes the obliquity of the insertion of the tendons, passing over them, into the bones. In their interior is a medullary canal or cavity, which con- tains the medulla, marrow or pith:—a secretion, whose office will be a theme for after inquiry. One great advantage of this canal is, that it makes the bone a hollow cylinder, and thus diminishes its weight. On many of the bones, prominences and cavities are perceptible. The eminences bear the generic name of apophyses or processes. Their great use is to cause the tendons to be inserted at a much greater angle into the bones they have to move. It may be seen, hereafter, that the nearer such insertion is to the perpendicular to the lever, the greater will be the effect produced. 1 Quetelet, Sur l'Homme, &c, Paris, 1835 ; or translation by Dr. Knox, p. 64, Edinb., 1842. 2 A Continuation of the Memoirs of Charles Mathews, Comedian, by Mrs. Mathews, Amer. edit., i. 165, Philad., 1839 : other cases are referred to by Isid. Geoffroy Saint- Hilaire, Histoire Generale et Particuliere des Anomalies de l'Organisation^chez l'Homme et les Animaux, i. 101, Bruxelles, 1837 ; and by Brachet, Physiologie Elementaire de l'Homme, 2de edit., ii. 480, Paris et Lyon, 1855. 3 Lectures on Physiology, Zoology, &c, by W. Lawrence, p. 434, Lond., 1819. 4 An Overland Journey round the World, Amer. edit., Part ii. p. 203, Philad., 1847. 224 MUSCULAR MOTION. The cavities are of various kinds. Some are articular: others for the insertion, reception, or transmission of parts. Those of insertion and reception afford space for attachment of muscles; those of transmission, &c, are frequently incrusted with cartilage; converted into canals by means of ligament, and furnished with a synovial membrane, which lubricates them, and facilitates the play of the tendons, for the passage of which they are destined. The mechanical structure of bone is a laminated framework incrusted by an earthy substance, and penetrated by exhalant and absorbent ves- sels, arteries, veins, and nerves. M. Herissant1 appears to have been one of the first who stated, that bone is essentially composed of two substances:—the one a cartilaginous basis or parenchyma, giving form to the part;—the other a peculiar earthy matter deposited on this basis, and communicating to it hardness. These two constituents can be readily demonstrated; the first, by digesting the bone in dilute chloro- hydric acid, which dissolves the earthy part, without acting on the animal matter; and the second, by burning the bone until all the ani- mal matter is consumed, whilst the earthy is left untouched. If we take a long bone and divide it longitudinally, we find that it is composed of three different substances, all of which may, however, be regarded as the same osseous tissue in various degrees of condensation. These are,—the hard or compact substance; the spongy or areolar; and the reticulated. The first is in the most condensed form; it exists at the exterior of the bone, and constitutes almost the whole of the shaft. The second is seen towards the extremities of a long bone, and in almost the whole of the short bones. In it, the laminae are less close, and have a cancellated appearance,—the cellules bearing the name of cancelli The reticulated substance is a still looser formation; the laminae being situate at a considerable distance; and the space between filled up with a series of membranous cells, which lodge the marrow. The marginal figures represent a longitudinal and a transverse section of tire same bone, in which this arrangement is well exhibited. We have seen the advantages of the expanded extremities of long bones, as regards the insertion of muscles; but it is obvious, that if these portions of the bone had consisted of the heavy compact tissue, the increased weight would have destroyed the advantages, that would otherwise have accrued; whilst, if the shaft of the bone, exposed, as it is, to external violence, had consisted of the spongy tissue only, it would not have offered the necessary resistance. It is, therefore, formed almost entirely of the compact tissue; so that a section of one inch, taken from the body of the bone, will not differ essentially in weight from an inch taken from the extremity. Nor does the cavity within the bones diminish their strength, as might at first sight be presumed. By enlarging the circumference, the contrary effect is produced; for we shall see, in the mechanical proem to the particular movements, that of two hollow columns, formed of an equal quantity of matter and of the same height, that, which has the larger cavity, is actually the stronger. A very important use of the cancellated or spongy texture of the bones was suggested by a distinguished individual of 1 Memoir, de l'Academ. des Sciences de Paris, pour 1758, p. 322. ANALYSIS OF BONES. 225 Fig. 349. this country, to whom surgical science, in particular, has been largely indebted. Dr. Physick1 asserts, that it serves to diminish, and, in ma-ny cases, to prevent, concussion of the brain, and of other viscera, in falls and blows. The demonstration, which he gives of this, is simple and satisfactory. If we suspend a series of six ivory balls by threads; raise the ball at one extremity of the series, and allow it to fall on the next to it, the farthest ball in the series is impelled to a distance which cor- responds with the momentum communicated by the first ball to the second. But if we substitute, for the middle ball of the series, a ball made of the cellular structure of bone, almost the whole of the mo- mentum is lost in this osseous structure; especially, if it be previously filled with tallow or well soaked in water, so as to bring it to a closer approximation to the living condition. Bones consist of earthy salts, and animal matter, intimately blended. The latter is chiefly cartilage, gelatin, and the peculiar fatty matter—the marrow. On reducing bones to powder, and digesting them in water, the fat rises and swims upon the sur- face; and the gelatin is dissolved. Accord- ing to the analysis of Berzelius, 100 parts of dry human bones consist of animal mat- ter, 33*3; basic phosphate of lime, 51*04; carbonate of lime, 11*30; fluoride of cal- cium, 2; phosphate of magnesia, 1*16; soda, chloride of sodium, and water, 1*2. It has been much doubted, however, whether flu- oride of calcium is contained in recent bones; whilst it is admitted to have been detected in fossil bones. According to Dr. Daubeny,2 it exists in the former, in about a quarter of the proportion in which it is present in the latter; but the proportions in different specimens of both kinds are variable. Dr. Daubeny ascribes the failure of those who have not detected fluorine except in fossil bones and teeth to the tenacity with which it is retained by animal matter; and to its being carried off with the carbonic acid evolved at the same time, too rapidly to act upon glass exposed to it. He, therefore, before submitting the bones to the action of strong sulphuric acid, burns away all the animal matters; removes the carbonic acid by dissolving them in chlorohydric acid; then throws down the earthy phosphates by caustic ammonia, and dries them. MM. Fourcroy and Yauquelin found in bones oxides of iron and manganese, silica, and albumen. Mr. Hatchett detected, also, a small Sections of a Bone. 1, 2. Longitudinal section of the ex- tremity. 3. Transverse section of the body. 1 Horner, Special and General Anatomy, &c, 8th edit., i. 83, Philad. 2 Philosophical Magazine, Aug., 1844. VOL. II.—15 1851. 226 MUSCULAR MOTION. quantity of sulphate of lime. Schreger gives the following as the proportions of animal and earthy parts: Infants. Adults. Aged. Animal matter......47-20 20-18 12-20 Earthy matter......48-48 74-84 84-10 95-68 95-02 96-30 The following are the average proportions, according to Lehmann,1 from his own analyses, and those of two other observers. Sebastian. Lehmann. Frerichs. Compact Bone. Spongy Bone. Organic . . . 63-66 32-28 31-2 37-82 Earthy . . . 63-34 67-72 68-8 62-18 Dr. Stark2 affirms, from the results of his experiments, that the mean proportion of animal matter in the bones of all vertebrate ani- mals is 33*91; of earthy 66*09; the mean proportion in the bones of man 33*39 of animal matter; 66*61 of earthy. The bones are enveloped by a dense fibrous membrane, termed, in the abstract, periosteum; but assuming different names according to the part it covers. On the skull, it is called pericranium: and its ex- tensions over the cartilages of prolongation are called perichondrium. The chief uses of this expansion are, to support the vessels in their passage to and from the bone, and to assist in its formation; for we find, that if the periosteum be removed from a bone, it becomes dead at the surface previously covered by the membrane, and exfoliates. In the foetus, it adds materially to the strength of bone, prior to the com- pletion of ossification. In the long bones, ossification commences at particular points; one generally in the shaft, and others at the different articular and other processes. These ossified portions are, for some time, separated from each other by the animal matter, which alone composes the intermediate portions of the bone; and, without this fibrous envelope, they would be too feeble, perhaps, to resist the strains to which they are exposed. The periosteum, moreover, affords a convenient insertion for muscles destined to act upon bones; and enables them to slide more readily when contracting: hence friction is avoided. The cavity of long bones is lined by a membrane—called medullary membrane or internal periosteum—which is supplied with numerous vessels; adheres to the internal surface of bone, and is not only con- cerned in its nutrition, but in the secretion of the marrow, and likewise of a kind of oily matter, which differs from marrow in being more fluid, and is contained in cells formed by the spongy substance, and in areolae of the compact substance. This is called oil of bones. Marrow is considered to be lodged in membranous cells, formed by an extension of the internal periosteum; whilst, according to Mr. How- ship,3 oil of bones is probably deposited in longitudinal canals—Haver- sian canals— which traverse the solid substance of the bone, and through which its vessels are transmitted. If a thin transverse section of long 1 Schmidt's Jahrbucher, No. vi., 1843. 2 Edinburgh Medical and Surgical Journal, April, 1845, p. 313. * Medico-Chirurg. Transact., vii. 393. NUMBER OF BONES. 227 bone be examined under a high magnifying power, the bony matter is observed to be arranged in concentric circles around the orifices of the canals as in Fig. 351. These circles are marked by a number of stel- lated dark spots formerly termed osseous corpuscles; but as they are minute cavities in the bony substance, now more appropriately called lacunoz. From these, fine pores or tubes, termed canaliculi, proceed, which traverse the substance of the bone, and communicate irregularly with each other. All the different lacunas communicate by means of the canaliculi with the Haversian canals; so that fluid may pass to every part of the osseous substance, and thus convey fluid for nutrition. They open, like- wise, into the great medullary canal, and into the cavities of the cancellated texture. Blood corpuscles cannot pass along them, as their largest diameter has not seemed to be more than from l-20000th to l-14000th of an inch; and the smallest not more than from 1-60000th to 1-40000th. The nature and fancied uses of marrow and oil of bones have been considered elsewhere.' The bones, periosteum, and marrow are, in the sound state, amongst the insensible parts of the frame. They are certainly not sensible to ordinary irritants; but, when morbid, exhibit intense sensibility. This applies, at least, to bones and the periosteum; the sensibility, which has been ascribed to the marrow, in disease, being probably owing to that of the prolonga- tions of the membrane in which it is con- tained. The number of the bones in the body is usually estimated at two hundred and forty, exclusive of the sesamoid, which are always found in pairs at the roots of the thumb and great toe; between the tendons of the flexor muscles and joints; and, occasionally, at the roots of the fingers and small toes. The bones are connected by means of articulations or joints, which differ materially from each other. To all the varieties, names are ap- propriated, which form a difficult task for the memory of the anatomical student. Technically, every part at which two bones meet, and are connected, is called an articulation, whether any degree of motion exists or not. This, indeed, is the foundation of the division that pre- vails at the present day,—the articulations being separable into two classes; the immovable or synarthroses, and the movable or diarthroses. Synarthroses are variously termed, according to their shape. When the articular surfaces are dovetailed into each other, the joint is called a suture. This is the articulation that prevails in the bones of the skull. Harmony is when the edges of bones are even, and merely touch; as in the bones of the head in quadrupeds and birds. When a pit in one bone receives the projecting extremity of another, we have a case of gomphosis. It is exhibited in the union between the teeth Haversian Canals, seen on a Longitudinal Section of the Compact Tissue of the Shaft of one of the Long Bones. 1. Arterial canal. 2. Venous canal. 3. Dilatation of another venous canal. 228 MUSCULAR MOTION. and their sockets. Lastly, schindylesis is when the lamina of one bone is received into a groove of another; as in the articulation of the vomer, which separates the nasal fossae from each other. The movable articulations comprise two orders:—amphiarthroses, in which the two bones are intimately united by an intermediate substance, of a soft Fig. 351. Transverse Section of Compact Tissue of Humerus magnified about 150 diameters. Three of the Haversian canals are seen, with their concentric rings ; also the corpuscles or lacnnn, with the canaliculi extending from them across the direction of the lamellae. The Haversian apertures had got filled with debris in grinding down the section, and therefore appear black in the figure, which represents the object as viewed with transmitted light. and flexible character, as in the junction of the vertebrae with each other; and diarthroses, properly so called. The last admit of three subdivisions—enarthroses or ball and socket joints; the condyloid in which, owing to the head being oval, the movements are not as easy in all directions as when it is spherical; and the ginglymoid or gingly- mus, in which the motion can occur in only one direction, as in a hinge. The farther subdivision of the joints belongs more to anatomy than to physiology. The articular surfaces of bones never come into immediate contact. They are tipped with a firm, highly elastic substance, called cartilage; which, by its smoothness, enables the bones to move easily upon each other; and may have some influence in deadening shocks, and de- fending the bones, which it covers. The arrangement of cartilage varies according to the shape of the extremity of the bone. If it be spherical, the cartilage is thick at the centre, and gradually diminishes towards the circumference. In the cavity, the reverse is the case; the cartilage is thin at the centre, and becomes thicker towards the circum- ference ; whilst on a trochlea or pulley its thickness is nearly every where alike. An admirable provision against displacement of bones at the articu- lations is seen in the ligaments. These, by the French anatomists, are distinguished into two kinds—fibrous capsules, and ligaments properly PHYSIOLOGY OF MUSCULAR MOTION. 229 so called. The former are a kind of cylindrical sac, formed of a firm, fibrous membrane; open at each extremity, by which they closely embrace the articular ends of bones; and loose, when the joint admits of much motion. In this way, the articulation is completely enclosed: they generally bear the name of capsular ligaments. The ligaments, properly so called, are bands of the same kind of tissue, which extend from one bone to another; by their resistance preserving the bones in situ; and by their suppleness admitting the necessary motion. The interior of all these articulations is lubricated by a viscid fluid, called synovia. This is secreted by a peculiar membrane of a serous nature; and its use is to diminish friction, and, at the same time, to favour adhesion. The mode in which it is secreted, and its chief pro- perties and uses, will be the subject of future inquiry. In certain of the movable articulations, fibro-cartilaginous substances, frequently called interarticular cartilages, are found between the articu- lar surfaces, and not adherent to either. These have been supposed to form a kind of cushion, which, by yielding to pressure, and returning upon themselves, may protect the joints to which they belong; and, accordingly, it is asserted, that they are met with in joints, which have to sustain the greatest pressure; but M. Magendie1 properly remarks, that they do not exist in the hip or ankle-joint, which have constantly to support the strongest pressure. The use, which he suggests, is more specious;—that they may favour the extent of motion, and prevent displacement. The stability of the joints is likewise aided by the manner in which muscles or tendons pass over them. These are contained in an aponeu- rotic sheath, to prevent their displacement; and thus the whole limb becomes well protected, and dislocation unfrequent, even in those joints, as that of the shoulder, which, as regards their osseous arrange- ment, ought to be very liable to displacement. It has been suggested by Weber, that the head of the thigh-bone is retained in situ, not by the power of the muscles or ligaments but by the pressure of the surrounding atmosphere; and Lauer,2 who repeated Weber's experiments under the directions of Fricke, of Hamburg, is of opinion, that atmospheric pressure must be classed among the means by which the lower extremity is kept in apposition with the trunk of the body. 2. PHYSIOLOGY OF MUSCULAR MOTION. By voluntary motion or that effected by the muscular system- of animal life, we mean contraction of the muscles under the influence of volition or will. This influence is propagated along the nerves to the muscles, which are excited by it to contraction. The encephalon, spinal marrow, nerves, and muscles are, therefore, organs of voluntary muscular con- traction. Volition is a function of the encephalon, and might have been with much propriety included under the physiology of the intellectual and moral acts; but as it is so intimately concerned with muscular motion, it was judged advisable to defer its consideration. That in man and 1 Precis Elementaire, 2de Mit., i. 292, Paris, 1823. 2 Zeitschrift fur die gesammte Medicin, Band ii. Heft 3. 230 MUSCULAR MOTION. the higher animals, it is a product of encephalic action is proved by many facts. If the brain be injured in any manner;—by fracture of the skull, or by effusion of blood, producing apoplectic pressure;—or if it be deprived of its functions by a strong dose of any narcotic sub- stance;—or if, again, it be in a state of rest, as in sleep:—volition is no longer exerted; and voluntary motion is impracticable. This is the cause why the erect attitude cannot be maintained during sleep; and why the head falls forward upon the chest, when somnolency is to such an extent as to deprive the extensor muscles of the back and head of their stimulus to activity.1 That an emanation from the encephalon is necessary is likewise proved by the effect of tying, cutting, com- pressing, or stupefying a nerve proceeding to a muscle: it matters not that the will may act; the muscle does not receive the excitation, and no motion is produced; a fact which proves, that nerves are the chan- nels of communication between the brain and the muscles. If, again, we destroy the medulla oblongata and medulla spinalis, we abolish all muscular motion, notwithstanding the brain may will, and the muscles be in a state of physical integrity ; because we have destroyed the parts whence the nerves proceed. In like manner, by successively slicing away the medulla spinalis from its base to the occiput, we paralyse, in succession, every muscle of the body that receives its nerves from the spinal marrow. Experiments of physiologists have confirmed the view, that the encephalon is the chief seat of volition. When it has been sliced away to a certain extent, the animal has been thrown into a state of stupor, attended with loss of sensibility, power of locomotion, and especially spontaneous motion ; and in writing, dancing, speaking, &c, we have indisputable evidence of its direction by the intellect. It is not so clear, that the seat of volition is restricted to the encephalon. There are actions of the yet living trunk, which appear to show, that an obscure volition may be exerted even after the brain has been sepa- rated from the rest of the body; and acephalous children have not only moved perceptibly when in utero, but at birth. Without refer- ring to the lowest classes of animals, which execute voluntary motions for a long time after they have been bisected, every one must have noticed the motions of decapitated fowls, which continue for a time, to run and leap, and apparently, to suffer uneasiness in the incised part. The feats of the Emperor Commodus are elucidative of this matter. Herodian relates, that he was in the habit of shooting at the ostrich, as it ran across the circus, with an arrow having a cutting edge; and, even when the shaft was true to its destination, and the head was severed from the body, it usually ran several yards before it dropped. Kaauw Boerhaave—nephew of the celebrated Hermann, himself an eminent medical teacher at St. Petersburg—asserts that he saw a cock, thus decapitated, run a distance of twenty-three feet. Cases are also recorded of men walking a few steps after decapitation, striking their breasts, &c.; but they can scarcely be regarded as authentic.2 In 1 Adelon, art. Encephale (Physiol.) in Diet, de Med., vii. 516, Paris, 1823; and Physiol, de l'Homme, ii. 25, 2de edit., Paris, 1829. 2 Adelon, op. citat., ii. 28 ; and Dr. J. R. Coxe, in Dunglison's Amer. Med. Intelli- gencer, for May 15, 1837. SEAT OF VOLITION. 231 countries where judicial execution consists in decapitation by the sword, sufficient opportunities must have presented themselves for testing this question; but no zealous Naturforscher appears to have been present to record them. Similar opportunities have likewise occurred under the operations of the guillotine. M. Legallois,1 in some experiments, which he instituted, for the pur- pose of determining the nervous influence on the heart, &c, found that rabbits, which he had deprived of their heads and hinder extremities, but still kept alive by artificial respiration, moved their fore paws when- ever he stimulated them by plucking their hairs. With regard to complete acephali, or those foetuses which are totally devoid of encephalon,—although they may vegetate in utero, they ex- pire after birth, owing to their being devoid of the medulla oblongata in which is the nervous system of respiration. Monsters have been born without the brain, but with part of the encephalon. These have been called, by way of distinction, anencephali or hemicephali. Where the medulla oblongata exists, they possess the nervous system of the senses, and of respiration, and are, consequently, able to live for a time after birth, and to exert certain muscular movements, as sucking, moving the limbs, evacuating the excretions, &c. M. Adelon asserts, that none of these facts ought to shake the proposition,—that in the superior animals, and consequently in man, the medulla spinalis and nerves are merely the conductors of volition or the locomotive will; and that volition is produced in the encephalon alone. His arguments on this point are not, however, characterized by that ingenuousness and freedom from sophism, for which his physiological disquisitions are generally distin- guished. " First of all," he observes, " the fact of the progression and motions of men and quadrupeds after decapitation is manifestly apo- cryphal; and even if we admit, that certain animals still execute certain movements after decapitation, are such evidently regular and ordained ? And, supposing them to be so, may not this have arisen from the con- formation of the parts, or from habits contracted by the organs? This last appears to us most probable; for if, from any cause whatever, the muscles of a part contract, they cause the part to execute such motions as the joints, entering into its composition, require; and which may, therefore, be similar to those produced by the will." He further at- tempts to deny the facts related of the lower classes of animals, and asserts, that" they are not evinced in the experiments instituted in our day." The cases, recorded to prove the defective sensibility of the lower tribes of animated nature, are, however, as has been elsewhere shown, incontestable.—The trunk of the wasp attempts to sting after the head has been removed; and an experiment made on the rattle- snake by Dr. Harlan,2 in the presence of Capt. Basil Hall, certainly demonstrates something like design in the headless trunk; and the cases, already referred to, on the authority of Drs. Le Conte and Dow- ler, exhibit almost miraculous phenomena of the kind in the decapitated alligator.3 Our conclusion ought probably to be, from all these cases,—that 1 ffiuvres, Paris, 1824. 2 Medical and Physical Researches, Philad., 1835. 8 See p. 153 of this volume. 232 MUSCULAR MOTION. volition is chiefly seated in the encephalon, but that an obscure action of the kind may originate, perhaps, farther down the cerebro-spinal axis. This conclusion, of course, applies only to the higher classes of animals; for we have seen, that the polypus is capable of division into several portions, so as to constitute as many distinct beings; and it is probable, that the principal seat of volition may extend much lower in the inferior tribes of created beings. Successful attempts have been made to discover, whether the whole brain is concerned in volition, or only a part. Porti©ns have been dis- organized by disease, and yet the person has not been deprived of voluntary motion; at other times, as in paralysis, the faculty has been impaired; and again, considerable quantities of brain have been lost, owing to accidents (in one case the author knew nineteen tea-spoonfuls), with equal immunity as regards the function in question. Experiments, executed on this subject, go still farther to confirm the idea, that voli- tion is not seated exclusively in the encephalon. MM. Eolando and Flourens1 performed several, with the view of detecting the seat of the locomotive will, or of that which presides over the general movements of station and progression; and they were led to fix upon the cerebral lobes. Animals, from which these were removed, were thrown into a sleepy, lethargic condition; were devoid of sensation and spontaneous motion, and moved only when provoked. On the other hand, M. Magen- die2 affirms, that the cerebral hemispheres may be cut deeply in different parts of their upper surface, without any evident alteration in the movements. Even their total removal, if it did not implicate the cor- pora striata, he found to produce no greater effect; or. at least, none but what might be easily referred to the suffering induced by such an experiment. The results, however, were not alike in all classes of ver- tebrated animals. Those mentioned were observed in quadrupeds, and particularly dogs, cats, rabbits, Guinea pigs, hedgehogs, and squirrels. In birds, the removal or destruction of the hemispheres—the optic tu- bercles remaining untouched—was often followed by the state of stupor and immobility described by MM. Rolando and Flourens; but, in numerous cases, the birds ran, leaped, and swam, after the hemispheres had been removed, the sight alone appearing to be destroyed. In rep- tiles and fish, the removal of the hemispheres seemed to exert little effect upon their motions. Carps swam with agility; frogs leaped and swam as if uninjured; and their sight did not appear to be affected. Magendie3 properly concludes from these experiments, that the spon- taneity of the movements does not belong exclusively to the hemi- spheres; that in certain birds, as the pigeon, adult rook, &c, this seems to be the case; but not so in other birds. To mammalia, reptiles, and fish,—at least such of them as were the subjects of experiment,—his conclusion is, however, applicable. Of the nature of the action of the brain in producing volition we know nothing. It is only in the prosecution of direct experiments on the encephalon that we can have an opportunity of seeing it during the execution of the function; but the process is too minute to admit of observation. Our knowledge is confined to the fact, that the encephalon 1 Op. citat. 2 Precis Ll.'mentaire. 3 Ibid..i. 336. NERVOUS CENTRE OF MUSCULAR CONTRACTION. 233 acts, and that some influence is projected from it along the muscles, which excites them to action; and accurately regulates the extent and velocity of muscular contraction. Yet volition is not the sole excitant of such contraction. If we irritate any part of the encephalon or spinal marrow, or any of the nerves proceeding from them, muscular movements are excited; but they are not regulated as when under the influence of volition. The whole class of involuntary motions, or rather of those executed by the muscular system of organic life, is of this kind, including the action of many of the most important organs,—heart, intestines, blood-vessels, &c. The involuntary muscles equally require a stimulus to excite them into action ; but, as their name imports, they are removed from the influence of volition. In certain diseased condi- tions, we find, that all the voluntary muscles assume involuntary mo- tions; but this is owing to the ordinary volition being interfered with, and to some direct or indirect stimulation affecting the parts of the cerebro-spinal axis concerned in muscular contraction; or, if the effect be local, to some stimulation of the nerve proceeding from the axis to the part. Of this kind of general involuntary contraction of voluntary muscles, we have a common example in the convulsions of children ; and one of the partial kind in cramp or spasm. The will, then, is the great but not the sole regulator of the supply of voluntary nervous influence. This is confirmed \>y experiment. If a portion of the spinal marrow be divided, so as to separate it from all communication with the encephalon, the muscles cannot be affected by the will; but they contract on irritating the part of the spinal marrow, from which its nerves proceed. It has, hence, been presumed by some physiologists, that volition is only the exciting and regulating cause of the nervous influx; and that the latter is the immediate agent in producing contraction; and they affirm, that as, in the sensations, the impression is made on the nerve, and perception effected in the brain, —so, in muscular motion, volition is the act of the encephalon, and the nervous influx to a part corresponds to the act of impression. With regard to the seat of this nervous centre of muscular contrac- tion, much discrepancy has existed amongst modern physiologists. It manifestly is not in the whole encephalon, as certain portions of it may be irritated in the living animal without exciting convulsions. Parts of it, again, may be removed without preventing the remainder from exciting muscular contraction when irritated. In the experi- ments of M. Flourens, the cerebral lobes were taken away, yet the animals, when stimulated, were susceptible of motion; and whenever the medulla oblongata was irritated, convulsions were produced. Its seat is not, therefore, in the whole encephalon. M. Rolando refers it to the cerebellum. He asserts, that on removing the cerebellum of living animals, without implicating any other part of the encephalon, they preserved their sensibility and consciousness, but were deprived of the power of motion. This occurred to a greater extent in propor- tion to the severity of the injury inflicted on the cerebellum. If the injury was slight, the loss of power was slight; and conversely. Im- pressed with the. resemblance between the cerebellum of birds and the galvanic apparatus of the torpedo; and taking into consideration the lamellated structure of the cerebellum, which, according to him, re- 234 MUSCULAR MOTION. sembles a voltaic pile; and the results of his experiments, which showed, that the movements diminished in proportion to the injury done to the cerebellum, Rolando drew the inference, that this part of the encephalon is an electro-motive apparatus for the secretion of a fluid analogous to the galvanic. This fluid is, according to him, trans- mitted along the nerves to the muscles, and excites them to contrac- tion. The parts of the encephalon concerned in volition would, in this view, regulate the quantity in which the motive fluid is secreted; and govern the motions; whilst the medulla oblongata, which, when alone irritated, always occasions convulsions, would put the encephalic extremity of the conducting nerves in direct or indirect communica- tion with the locomotive apparatus. This ingenious and simple theory is, however, far from being corro- borated by the fact, mentioned by M. Magendie,1 that he is annually in the habit of exhibiting to his class animals deprived of cerebellum, which are capable of executing regular movements. For example, he has seen the hedgehog and Guinea-pig, deprived not only of brain but of cerebellum, rub the nose with its paw, when a bottle of strong acetic acid was held to it; and he remarks, that a single positive fact of the kind is worth all the negative facts that could be adduced. He far- ther observes, that there could be no doubt of the entire removal of the brain in his experiments. The experiments of Magendie are, how- ever, equally adverse to the hypothesis of M. Flourens, that the cere- bellum is the regulator or balancer of the movements. Some anatomi- cal observations by Mr. Solly2 would seem to show, that there is a direct communication between the motor tract of the spinal marrow and the cerebellum. The corpora pyramidalia have been generally supposed to be formed by the entire mass of the anterior or motor columns of the spinal cord, but Mr. Solly shows, that not more than one-half of the anterior column enters into the composition of these bodies; and that another portion, which he terms "antero-lateral column," when traced on each side in its progress upwards, is found to cross the cord below the corpora olivaria, forming, after mutual de- cussation, the surface of the corpora restiformia; and being ultimately continuous with the cerebellum. Others, again, have estimated the encephalon to be the sole organ of volition, .and have referred the nervous action, which produces the " locomotive influx," as it is termed, exclusively to the spinal marrow; and hence they have termed the spinal marrow, and the nerves issuing from it, the "nervous system of locomotion" It is manifest, however, that the encephalon must participate with the medulla spinalis in this function; inasmuch as not only does direct irritation of several parts of the former excite convulsions, but we see them frequently as a con- sequence of disease of the encephalon; yet, as has been remarked, there is some reason for believing, that, in the upper classes of ani- mals, an obscure volition may be exercised for a time, even when the encephalon is separated from the body. It need scarcely be said, that ' Precis, &c, i. 340. 2 Transactions of the Royal Society for 1836; and Solly on the Brain, Amer. edit., Phila., 1848. ENCEPHALIC SEAT OF MUSCULAR MOTION. 235 we are as ignorant of the character of this influx as we are of that of the nervous phenomena in general. The parts of the encephalon and spinal marrow, concerned in mus- cular motion, are very distinct from those that receive the impressions of external bodies. The function of sensibility is comprised in the me- dulla oblongata and in the posterior column of the spine, whilst the cere- bro-spinal organs of muscular motion appear to be the corpora striata, the thalami nervorum opticorum, at their lower part; the crura cerebri; the pons Varolii; the peduncles of the cerebellum ; the lateral parts of the medulla oblongata, and the anterior column of the medulla spi- nalis. This is proved by direct experiment, as will be shown presently; and, in addition to this, pathology furnishes us with numerous examples of their distinctness. In various cases of hemiplegia or palsy of one side of the body,—which is of encephalic origin,—we find motion almost lost; yet sensibility may be slightly or not at all affected ; and, on the other hand, instances of loss of sensation have been met with, in which the power of voluntary motion has continued. Modern dis- coveries in the system of vertebral nerves exhibit how this may hap- pen. A considerable space may exist between the roots of a nerve, one of which shall be destined for sensation, the other for motion; yet both may pass out enveloped in one sheath;—the same nervous cord thus conveying the two irradiations, if they may be so termed. Ac- cording to Sir Charles Bell's system, the spinal column is divided into three tracts; the anterior for motion; the posterior for sensibility; and the two are kept separate and united by the third—the column for respiration. The existence of the last column is now admitted by few.1 The experiments performed by the French physiologists especially,— for the purpose of discovering the precise parts of the encephalon con- cerned in muscular motion,—have attracted great and absorbing interest. We wish it could be said, that the results have been such as to afford determinate notions on the subject. According to those of M. Flou- rens, the cerebral lobes preside over volition, and the medulla oblon- gata over the locomotive influx: to the latter organ he assigns, also, sensibility. We have seen, that the results of his experiments have been contested; and with them, of course, his deductions. The facts and arguments, already stated, throw doubts on all except the last pro- position, which refers sensibility to the medulla oblongata; and even it is not restricted to that organ, or group of organs, whichsoever it may be considered. MM. Foville and Pinel Grand-Crmmp2 have affirmed that the cere- bellum is the seat of sensibility. To this conclusion they were led by the remarks they had made, in the course of their practice, that the cases of paralysis of sensibility, which fell under their notice, suc- ceeded more especially to morbid conditions of the encephalon. In this view they conceive themselves supported by the discovery of columns in the spinal marrow destined for particular functions; and, as the postero-lateral column is found to be the column of sensibility, and the cerebellum seems to be formed from this column, they think it ought to be possessed of the same functions. M. Adelon3 remarks, 1 See vol. i. p. 643. 2 Sur le Systeme Nerveux, Paris, 1820. 8 Op. citat., ii. 38. 236 MUSCULAR MOTION. that Willis professed a similar notion, and that he considered the cere- bral lobes to be the point of departure for the movements, and the cerebellum the seat of sensibility. In his first volume, however, he had cited more correctly the views of Willis. " Willis says positively," he remarks, " that the corpora striata are the seat of perception; the medullary mass of the brain, that of memory and imagination; the corpus callosum, that of reflection; and the cerebellum, the source of the motive spirits." Willis, in truth, regarded the cerebellum as sup- plying animal spirits to the nerves of involuntary functions, as the heart, intestinal canal, &c. The opinions of Foville and Pinel Grand- Champ are, however, subverted by the experiments of Rolando, Flourens, and Magendie, which show, that sensation continues, not- withstanding serious injury to, and even entire removal of, the cere- bellum. By other physiologists, the two functions have been assigned re- spectively to the cineritious and medullary parts of the brain; some asserting, that the seat of sensibility is more especially in the latter, and the motive force in the former. According to Treviranus, the more medullary matter an animal has in its brain and spinal marrow, in proportion to the cineritious, the greater will be its sensibility. To this, however, M. Desmoulins1 objects, that in many animals, the spinal marrow is composed exclusively of medullary matter [?]; and consequently they ought not only to be the most sensible of all, but to be wholly devoid of the power of motion. Others, again, as MM. Foville and Pinel Grand-Champ have reversed the matter; assigning sensibility to the cineritious substance, and motility to the medul- lary. From these conflicting opinions, it is obviously impossible to sift anything categorical; except that we are ignorant of the special seat of these functions. A part of the discrepancy in the results must be ascribed to organic differences in the animals which were the sub- jects of the experiments. This was strikingly exemplified in those instituted by M. Magendie, which have been cited. Similar contra- riety exists in the experiments and hypotheses, regarding the particu- lar parts,of the encephalon that are concerned in determinate move- ments of the body. The results of many of those are, indeed, so strange, that did they not rest on eminent authority they might be classed among the romantic. It has been already remarked, that Rolando considered the cerebel- lum to be an electro-motive apparatus, producing the whole of the gal- vanic fluid necessary for the motions. M. Flourens, on the other hand, from similar experiments, independently performed, and without any knowledge of those of Rolando, affirmed it to be the regulator and balancer of the locomotive movements; and he asserted, that, when removed from an animal, it could neither maintain the erect attitude, nor execute any movement of locomotion ; nor, although possessing all its sensations, could it fly from danger it saw menacing it. The same view has been advocated by M. Bouillaud, who has detailed eighteen experiments in which he cauterized the cerebellum, and found that, in all, the functions of equilibration and progression were disordered. The 1 Anatomie des Systemes Nerveux, &c, Paris, 1825. ENCEPHALIC SEAT OF MUSCULAR MOTION. 237 experiments of M. Magendie' on this subject are pregnant with import- ant novelty. We have already referred to those that concern the cere- bral hemispheres and cerebellum as the encephalic organs of the general movements, in the mode suggested by MM. Rolando and Flourens, and others. M. Magendie affirms, in addition, " that there exists, in the brain, four spontaneous impulses or forces, which are situate at the extremity of two lines cutting each other at right angles; the one impelling forwards; the second backwards; the third from right to left, causing the body to rotate; and the fourth from left to right, occasion- ing a similar movement of rotation." The first of these impulses he fixes in the cerebellum and medulla oblongata; the second in the cor- pora striata; and the third and fourth in each of the peduncles of the cerebellum. 1. Forward Impulse.—It has often been observed* by those who have made experiments on the cerebellum, that injuries of it cause animals to recoil manifestly against their will. M. Magendie2 asserts, that he has frequently seen them, when wounded in the cerebellum, make an attempt to advance, but be immediately compelled to run back; and he says that he kept a duck for eight days, the greater part of whose cerebellum he had removed, which did not move forwards during the whole of that time, except when placed on water. Pigeons, into whose cerebella he thrust pins, constantly walked and flew backwards, for more than a month afterwards. Hence, he concludes, that there exists, either in the cerebellum or medulla oblongata, a force of impulsion, which tends to cause animals to go forward. He thinks it not impro- bable, that this force exists in man; and states that Dr. Laurent, of Versailles, exhibited to him, and to the Academie Royale de Medecine, a young girl, who, in the attacks of a nervous disease, was obliged to recoil so rapidly, that she was incapable of avoiding bodies or pits behind her; and was, consequently, exposed to serious falls and bruises. This force, he affirms, exists only in the mammalia and birds;—certain fish and reptiles, on which he experimented, appearing to be unaffected by the entire loss of the cerebellum. 2. Backward Impulse.—M. Magendie found,3 when the corpora striata were removed, that the animal darted forward with great rapidity; and if stopped, still maintained the attitude of running. This was par- ticularly remarked in young rabbits; the animals appearing to be impelled forward by an inward and irresistible power, and passing over obstacles without noticing them. These effects were not found to take place, unless the white, radiated part of the corpora striata was cut: if the gray was alone divided, no modification was produced in the movements. If only one of the corpora was removed, the rabbit remained master of its movements, directed them in different ways, and stopped when it chose; but, immediately after the removal of the other, all regulating power over the motions appeared to cease, and it was irresistibly impelled forwards. In the disease of the horse, called, by the French, immobilite, the animal is often capable of walking, trotting, and galloping forward with rapidity; but he does not back; and fre- quently it is impracticable to arrest his motion forwards.- M. Ma- 1 Op. citat., i. 345. 2 Precis, i. 341. 3 Op. cit., i. 337. 238 MUSCULAR MOTION. gendie1 asserts, that he has opened several horses that died in this con- dition; and found, in all, a collection of fluid in the lateral ventricles, which had produced a morbid change on the surface of the corpora striata, and must have exerted a degree of compression on them. Similar pathological cases occur in man. M. Magendie relates the case of a person, who became melancholic, and lost all power over his movements; continually executing the most irregular and fantastic antics; and frequently compelled to walk exclusively forwards or back- wards until stopped by some obstacle. In this case, recovery occurred; and, accordingly, there was no opportunity for investigating the ence- phalic cause. M. Itard describes two cases, in which the patients were impelled, in paroxysms, to run straight forward, without the power of changing their course, even when a river or precipice was before them. A case is related by M. Piedagnel,2 which is more to the purpose as an opportunity occurred for post mortem examination. The subject of it also was irresistibly impelled to constant motion. "At the time of the greatest stupor," says M. Piedagnel, " he suddenly arose; walked about in an agitated manner; made several turns in his chamber, and did not stop until fatigued. On another occasion, the room did not satisfy him; he went out, and walked as long as his strength would permit. He remained out about two hours, and was brought back on a litter." M. Piedagnel adds, "that he seemed impelled by an insur- mountable force," which kept him in motion, until his powers failed him. On dissection, several tubercles were found in the right cerebral hemisphere, especially at its anterior part; and at the side of the cor- pora striata. These had produced much morbid alteration in that hemisphere; and had, at the same time, greatly pressed on the other. From these facts, M. Magendie infers it to be extremely probable, that, in the mammalia and in man, a force of impulsion always exists, which tends to impel backwards, and is, consequently, the antagonist to the force seated in the cerebellum. 3. Lateral Impulse.—If the peduncles of the cerebellum—crura cere- belli—be divided in a living animal, it immediately begins to turn round, as if impelled by some considerable force. The rotation or circumgyration is made in the direction of the divided peduncle—M. Longet says, in the opposite direction—and, at times, with such rapidity, that the animal makes as many as sixty revolutions in a minute. The same kind of effect is produced by any vertical section of the cerebellum, which implicates from before to behind the whole substance of the medullary arch formed by that organ above the fourth ventricle; but the movement is more rapid, the nearer the section is to the origin of the peduncles; in other words to their point of junc- tion with the pons Varolii. M. Magendie3 affirms, that he has seen this movement continue eight days without stopping, and apparently without any suffering. When an impediment was placed in the way, the motion was arrested; and, under such circumstances, the animal frequently remained with its paws in the air, and ate in this attitude. 1 Op. cit., i. 338. 2 .Magendie, Journal de Physiologie, torn. iii. ; and Precis Elementaire, i. 338. 3 Precis, &c, i. 343. ENCEPHALIC SEAT OF MUSCULAR MOTION. 239 What he conceives to have been one of his most singular experiments was,—the effect of the division of the cerebellum into two lateral and equal halves: the animal appeared to be alternately impelled to right and left, without retaining any fixed position: if he made a turn or two on one side, he soon changed his motion and made as many on the other. M. Serres1—who is well known as a writer on the compa- rative anatomy of the brain, and must have had unusual opportunities for observation at the Hospital La Pitie to which he was attached— gives the case of an apoplectic, who presented, amongst other symp- toms, the singular phenomenon of turning round, like the animals in those experiments; and, on dissection, an apoplectic effusion was found in that part of the encephalon. On dividing the pons Varolii verti- cally, from before to behind, M. Magendie2 found, that the same rotary movement was produced: when the section was to the left of the median line, the rotation was to the left, and conversely ; but he could never succeed in making the section accurately on the median line. From these facts he concludes, that there are two forces, which are equilibrious by passing across the circle formed by the pons Varolii and cerebellum. To put this beyond all question, he cut one peduncle, when the animal immediately rolled in one direction; but on cutting the other or the one on the opposite side, the movement ceased, and the animal lost the power of keeping itself erect, and of walking. From the results of all his experiments, M. Magendie infers, that an animal is a kind of automatic machine, wound up for the performance of certain motions, but incapable of producing any other. The figure of the base of the brain in the margin, will explain, more directly, the impulses described by this physiologist. The cor- pora striata are situate in each hemisphere, but their united impulses may be represented by the arrow A; the impulse seated in the cerebellum, by the arrow B; and those in each peduncle of the cerebellum, p, p, by the arrows C and D respectively. Whenthe impulse backwards is from any cause destroyed, the animal is given up to the for- ward impulse, or that represent- ed by the arrow B; and con- versely. In like manner, the destruction of one lateral im- pulse leaves the other without an antagonist, and the animal moves in the direction of the arrow placed over the seat of the im- pulsion that remains. In a state of health, all these impulsions being Direction of Encephalic Impulses, according to Magendie. Magendie's Journ. de Physiol., iv. 405. 2 PrJcis, &c, p. 344. 240 MUSCULAR MOTION. nicely antagonized, they are subjected to the influence of volition; but in disease they may be so modified as to be entirely withdrawn from its control. These four are not the only movements excited by particular injuries done to the nervous system. M. Magendie' states, that a circular move- ment to the right or left, similar to that of horses in a circus, was caused by the division of the medulla oblongata, to the outer side of the cor- pora pyramidalia anteriora. When the section was made on the right side, the animal turned, in this fashion, to the right; and to the left, if the section was made on that side. The parts, according to Dr. Brown-Sequard,2 which can be injured without producing turning are, the cerebral hemispheres, the cerebel- lum, the corpora striata, the corpus callosum, the spinal marrow, and the olfactory and optic nerves. Every other portion of the cerebro- spinal centres is able to produce turning or rolling. He found, also, that they were produced by tearing the facial nerve and by a puncture or section of the auditory nerve. Pathology has, likewise, indicated the brain as the seat of different bodily movements. Diseases of the encephalon have been found not only to cause irregular movements or convulsions but paralysis of a part of the body, leaving the rest untouched. Hence it has been concluded, that every motion of every part has its starting point in some portion of the brain. The ancients were well aware, that in cases of hemiplegia, the encephalic cause of the affection is found in the opposite hemisphere. Attempts have been made to decide upon the precise part of the encephalon in which the decussation takes place. Many have conceived it to be in the commissures ; but the greater num- ber, perhaps, have referred it to the corpora pyramidalia. These, the researches of Gall and Spurzheim3 and others, had pointed out as de- cussating at the anterior surface of the marrow, and as being apparently continuous with the radiated fibres of the corpora striata; and an opinion has prevailed, that the paralysis is of the same side as the encephalic affection, or of the opposite, according as the affected part of the brain is a continuation of fasciculi, which do not decussate—of the corpora olivaria, for example—or of the corpora pyramidalia, which do. M. Serres,4 however, affirms, that affections of the cerebellum, pons Varolii, and tubercula quadrigemina, exert their effects upon the oppo- site side of the body, and he supports his statement by pathological cases and direct experiment. M. Magendie5 divided one pyramid from the fourth ventricle ; yet no sensible effect was produced on the move- ments; certainly, there was no paralysis, either of the affected or oppo- site side; he then divided both pyramids about the middle, and no apparent derangement occurred in the motions—a slight difficulty in progression being alone observable. The section of the posterior pyra- mids was equally devoid of perceptible influence on the general move- ments ; and to cause paralysis of one half the body, it was necessary to divide the half of the medulla oblongata, when the corresponding 1 Prpcis, &c, p. 345. 2 Med. Examiner, August, 1852, p. 498. s Recherches sur le Systeme Nerveux, &c, sect, vi., Paris, 1809. 4 Anatomie Com par e du Cerveau, Paris, 1824. 6 q^ cit. ENCEPHALIC SEAT OF MUSCULAR MOTION. 241 side became,—not immovable, for it was affected by irregular move- ments ; and not insensible, for the animal moved its limbs when they were pinched,—but incapable of executing the determinations of the will. These views are not exactly in accordance with the general idea, that disease, confined to one hemisphere of the brain, or cerebellum, and to one side of the mesial plane in the tuber annulare, constantly affects the opposite side; whilst disease, confined to one of the lateral columns of the medulla oblongata and medulla spinalis, affects the cor- responding side of the muscular system;—the encephalon having a crossed,—the medulla a direct effect.1 The crossing of the fibres at the anterior surface of the marrow would not, however, account for the loss of sensation in hemiplegia. Mr. Hilton2 has examined carefully the continuation upwards of the anterior and posterior columns of the spinal marrow into the medulla oblongata, and found, that the decussation at the upper part of the marrow belongs in part to the column for mo- tion, and in part to the column for sensation; and farther, that the decussation is only partial with respect to either of the columns. It has been elsewhere shown,3 that the decussation of the sensitive nerve-fibres, in the opinion of Dr. Brown-Sequard,4 takes place in the spinal cord ; and the same observer infers from his experiments, that the voluntary nerve-fibres appear to make their whole decussation, or, at least, the greater part of it in the inferior portion of the medulla ob- longata ; and "not in the other parts of the isthmus of the encephalon," as has been imagined by many. The result of the examination of morbid cases has induced some physiologists to proceed still farther in their location of the encephalic organs of muscular motion; and to attempt an explanation of para- plegia, or cases in which one half the body, under the transverse bi- section, is paralyzed. MM. Serres, Foville, and Pinel Grand-Champ assert, that the anterior radiated portion of the corpora striata presides over the movements of the lower limbs; and the optic thalami over those of the upper; and that according as the extravasation of blood, in a case of apoplexy, occurs in one of these parts, or in all, the para- lysis is confined to the lower or to the upper limbs, or extends over the whole body. In 1768, M. Saucerotte5 presented a prize memoir to the Academie Royale de Chirurgie, of Paris, in which a similar view was expressed. He had concluded, from experiments, that affections of the anterior parts of the encephalon paralyse the lower limbs, whilst those of the posterior parts paralyse the upper. M. Chopart,—in a prize essay, crowned in 1769, and contained in the same volume with the last,—refers to the results of experiments by M. Petit, of Namur, which appeared to show, that paralysis of the opposite half of the body was not induced by injury of the cerebral hemisphere, unless the cor- 1 Lectures on the Nervous System and its Diseases, hy Marshall Hall, M. D., &c, Lond., 1836, p. 34, or Amer. edit., Philad., 1836. 2 Proceedings of the Royal Society, No. 34, for 1837-8 ; also, Solly on the Brain, p. 145, Lond., 1836; and Dr. John Reid, Edinb.'Med. and Surg. Journ., Jan., 1841, p. 12. 1 Vol. i. p. 653. 4 Experimental and Clinical Researches on the Physiology and Pathology of the Spinal Cord and some other parts of the Nervous Centres, p. 29, Richmond, 1855. 6 Prix de l'Academie Royale de Chirurgie, vol. iv. p. 373, Paris, 1819. VOL. II.—16 242 MUSCULAR MOTION. pora striata were cut or removed. The experiments by Saucerotte were repeated by M. Foville, and are detailed in a memoir, crowned by the Academie Royale de Medecine, of Paris, in 1826. They were attended with like results. In cats and rabbits, he cauterized, in some, the anterior part of the encephalon; in others, the posterior: in every one of the former, paralysis of the posterior, and in the latter, of the anterior extremities succeeded. Having in one animal mutilated the whole of the right hemisphere, and only the anterior part of the left, he found that the animal was paralysed in the hinder extremities, and in the paw of the left fore-leg; but that the paw of the right remained active.1 Lastly, the motions of the tongue or of articulation are sometimes alone affected in apoplexy. The seat of this variety- of muscular motion has been attempted to be deduced from pathological facts. M. Foville places it in the cornu ammonis and temporal lobe; and M. Bouillaud2 in the anterior lobe of the brain, in the medullary sub- stance,—the cineritious being concerned, he conceives, in the intel- lectual part of speech. It is sufficiently obvious, from the whole of the preceding detail, that the mind must still remain in doubt, regarding the precise part of the encephalon engaged in the functions of muscular motion. The experi- ments of M. Magendie are, perhaps, more than any others, entitled to consideration. They appear to have been instituted without any par- ticular bias; to subserve no particular theory; and are supported by pathological facts furnished by others. He is, withal, a practised experimenter, and one to whom physiology has been largely indebted. His vivisections have been more numerous, perhaps, than those of any other individual. His investigations, however, on this subject clearly show, that owing to the different morphology of animals, we cannot draw as extensive analogical deductions from comparative anatomy and physiology as might be anticipated. The greater source of dis- crepancy, indeed, between his experiments and those of MM. Rolando and Flourens, appears to have been the employment of different ani- mals. Where the same animals were the subjects of the vivisections, the results were in accordance. The experiments demand careful repetition, accompanied by watchful and assiduous observation of pathological phenomena; and, until this is effected, we can, perhaps, scarcely feel justified in deducing, from all these experiments and in- vestigations, more than the general propositions regarding the influ- ence of the cerebro-spinal axis on muscular motion, which we have enunciated. It has been already shown, however, that strong evidence may be adduced in favour of the view of M. Flourens, that the cere- bellum is the regulator or co-ordinator of the muscular movements,3 and it is the one now embraced by the generality of physiologists; although it must be admitted, with M. Longet,4 that "the precise deter- mination of the uses of the cerebellum is one of the most embarrassing problems in physiology." 1 Adelon, Physiologie de l'Homme, edit, cit., ii. 44. 2 Magendie's Journal de Physiologie, torn. x.; also, Belhomme, Archiv. General, da Medecine, Mai, 1845. 3 Longet, Anatomie et Physiologie du Systeme Nerveux, i. 703, Paris, 1842. * Traite de Physiologie, ii. 272, Paris, 1850. NERVES OF MOTION. 243 The nerves, it has been shown, are the agents for conducting the locomotive influence to the muscles. At one time, it was universally believed, that the same nerve conveys both sensation and volition; but the pathological cases, that not unfrequently occurred, in which either sensation or voluntary motion was lost, without the other being neces- sarily implicated; and, of late years, the beautiful additions to our knowledge of the spinal nerves, for which we are mainly indebted to Sir Charles Bell,1 and M. Magendie,2 have satisfied the most sceptical, that there are separate nerves for the two functions, although they may be enveloped in the same neurilemma or nervous sheath; and may con- stitute one nervous cord. We have more than once asserted, that the posterior part of the spinal marrow, with the nerves proceeding from it, has been considered to be chiefly concerned in the function of sensi- bility ; and the anterior column, and the nerves connected with it, to be inservient to muscular motion; whilst a third intervening column, in the opinion of Sir Charles Bell, is the source of all the respiratory nerves, arid of the various movements connected with respiration and expression. It is proper, here again, to observe, that although these two distinguished pl^siologists agree in their assignment of function to the anterior and posterior columns of the spinal marrow, Bellingeri3 has deduced very different inferences from like experiments. He as- serts, that having divided on living animals, either the anterior roots of the spinal nerves, and the anterior column of the medulla spinalis— or the posterior roots of these nerves, and the posterior column of the medulla, he did not occasion, in the former case, paralysis of motion, and in the latter, loss of sensation; but only, in the one, the loss of all movements of flexion; and in the other, of those of extension. In his view, the brain and its prolongations,—crura cerebri, corpora pyra- midalia, anterior column of the spinal marrow, and the nerves con- nected with it,—preside over the movements of flexion; and, on the contrary, the cerebellum and its extensions, as the posterior column of the medulla spinalis, and the nerves connected with it, preside over those of extension: he infers, in other words, that there is an antago- nism between these sets of nerves. The prima facie evidence is against the accuracy of Bellingeri's experiments. The weight of authority in opposition to him is, in the first place, preponderant; and in the second place, it seems highly improbable, that distinct nerves should be employed for the same kind of muscular action. Moreover, in experiments on the frog, Professor Miiller established the correctness of the views of Bell. It seems, that the different physiologists, who engaged in the inquiry before he did, employed warm-blooded animals in their experiments, and he imagines, that the pain, resulting from the necessarily extensive wounds, may have had such an effect on the nervous system as to modify, and perhaps even counteract, the results. Miiller employed the frog, whose sensibility is less acute, and tenacity 1 The Nervous System, &c, 3d edit., Lond., 1837, and Narrative of the Discoveries of Sir Charles Bell in the Nervous System, by A. Shaw, London, 1839. 2 Precis Elementaire, &c, 2de edit., i. 216. 3 Exper. Physiol, in Med. Spinal. August, Taurin., 1825; Ragionamenti, Sperienze, &c, comprovanti l'Antagonismo Nervoso, &c, Torino, 1833; and an Analysis of the same, in Edinb. Med. and Surg. Journ., Jan., 1835, p. 160. 244 MUSCULAR MOTION. of life greater. If the spinal marrow of this animal be exposed, and the posterior roots of the nerves of the lower extremities be cut, not the least motion is perceptible when the divided roots are touched by mechanical means, or galvanism. But if the anterior roots be touched, the most active movements are instantly observed. These experiments, Miiller1 remarks, are so readily made, and the evidence they afford is so palpable, that they leave no doubt as to the correctness of the views of Sir Charles Bell. Experiments, by M. Magendie, and by Dr. Kronenberg,2 of Moscow, have shown, that a portion of the fibres of the sensitive roots extends to the point of union between them and the anterior roots, and is re- flected to the anterior column of the spinal marrow;—the return or reflection of the fibres taking place near the junction of the two roots. This arrangement of the fibres accounts for the fact, often noticed by physiologists, that some degree of sensibility appears to be manifested, in experiments on animals, when the motor roots of the nerves are irritated. The sensibility of the portio dura, a motor nerve, has been long known, and properly ascribed to its receiving filaments of the fifth pair. Motions can be excited by irritating the posterior root, which are owing to its connexion with the spinal cord. This irritation does not act immediately upon the muscles through the trunk of the nerve, which the posterior root contributes to form; but it excites a motor impulse in the spinal cord, which is propagated through the anterior roots to the periphery of the system. In the ordinary case of the action of a voluntary striped or striated muscle, the nervous influence, emanating from some part of the cerebro- spinal axis, under the guidance of volition, proceeds along the nerves with the rapidity of lightning, and excites the muscle to contraction. The muscle, which was before smooth, becomes rugous; the belly more tumid; the ends approximate, and the whole organ is rendered thicker, firmer, and shorter. The researches of Mr. Bowman3 have shown, that in the state of contraction the transverse strias, before described as ex- isting in each fibre, approach each other; whilst its diameter is increased; hence the solid parts are more closely approximated, and the fluid which previously existed between them is pressed out so as to form bulla? in the sarcolemma, as represented in Fig. 353, from Mr. Bowman. The Fig. 353. Muscular Fibre of Dytiscus in contraction. marginal representations, Fig. 354, of the muscular fibre of the skate, at rest and in contraction, are also from Mr. Bowman. It is proper to 1 Elements of Physiology, by Baly, p. 644, Lond., 1838. 2 Muller's Archiv., Heft v. 1839. 3 Art. Muscular Motion, in Cyclop, of Anat. and Physiol., Part xxiv. p. 525, London, July, 1842; and Philosophical Transactions for 1840-1841. STATE OF MUSCLES IN ACTION. 245 Fig. 354. remark, however, that these representations are of muscular fibres when in an unnatural condition,—separated, that is, from the rest of the economy, and it cannot be considered established, that contraction ex- cited by the agency of the nerves is accomplished in precisely the same manner. With regard to the degree of contraction or shortening, which a muscle experiences, some difference of sentiment has prevailed. Ber- nouilli and Keill1 estimated it at one-third of the length; and Dumas2 carried it still higher. It must, of course, be proportionate to the length of the fibres,—being greater, the longer the fibres. It has, also, been a sub- ject of experiment and speculation, whether the bulk and the specific gravity of a mus- cle be augmented during contraction. Bo- relli3and Sir Anthony Carlisle4 affirm, that its bulk is increased. In the experiments of the latter, the arm was immersed in a jar of water, with which a barometrical tube was connected; and when the muscles were made to contract strongly, the level of the water in the tube was raised. Glisson, however, from the same experiment, de- duced opposite conclusions; Swammerdam and Ermann5 appear to be of their opinion; but Sir Gilbert Blane,6 Mr. Mayo,7 Barzel- lotti,8 MM. Dumas and Prevost,9 and Va- lentin,10 during the most careful experi- ments, could see no variation in the level of the fluid; and, consequently, do not be- lieve, that the size of a muscle is modified by contraction. Sir Gilbert enclosed a living eel in a glass vessel filled with water, the neck of which was drawn out into a fine tube; he then, by means of a wire in- troduced into the vessel, irritated the tail of the animal, so as to excite strong contraction, during which he noticed, that the water in the vessel remained stationary. He, likewise, compared the two sides of a fish, one of which had been crimped, and thus brought into a state of strong contraction;—the other left in its natural condition: their specific gravity was the same. The experiment of Barzellotti was the following. Muscular Fibre of Skate. In a state of rest 0), and in three dif- ferent stages of contraction (2, 3, 1). 1 Tentamina-Medico-Physica, Lond., 1718. 2 Principes de Physiologie, &c, 2de edit., Paris, 1806. 3 De Motu Animalium, addit. J. Bernouillii, Medit. Mathem. Muscul., L. B. 1710. 4 Philos. Transact, for 1805, pp. 22, 23. 5 Gilbert's Annalen, p. 40, 1812. 6 A Lecture on Muscular Motion, &c, Lond., 1778 ; and Select Dissertations, &c, p. 239. 7 Anatomical and Physiological Commentaries, i. 12 ; and Outlines of Human Phy- siology, 3d edit., p. 35, Lond., 1833. s Esame di alcune moderne Teorie intorno alia Causa prossima della Contrazione moscolare, Siena, 1796. 9 Op. citat., and Magendie, Pr'cis, &c, i. 222. 10 Lehrbuch der Physiologie des Menschen, S. 42, Braunschweig, 1844; and Grun- driss der Physiologie, S. 218, Braunschweig, 1846. 246 MUSCULAR MOTION. He suspended, in a glass vessel, the posterior half of a frog; filled the jar with water, and closed it with a stopper traversed by a narrow, graduated tube. The muscle was then made to contract by means of galvanism, but in no case was the level of the liquid in the tube changed. It may, then, be concluded, that the bulk of a muscle is not much, if at all, greater when contracted than when relaxed. Professor E. Weber, who repeated the experiments of Ermann, detected an increase of bulk, but it was exceedingly small.1 During contraction, the muscle is sometimes so rigid and elastic as to be capable of vibration when struck. The ordinary firm state is well exhibited by the masseter, when the jaws are forcibly closed; and some men possess the power of producing sonorous vibrations by strik- ing the contracted biceps with a metallic rod. It has been a matter of dispute whether the quantity of blood circu- lating in a muscle is diminished during contraction. At one time, it was universally believed, that such diminution existed, and that it ac- counted for the diminished size of the muscle during contraction. This last allegation we have shown to be inaccurate; and no correct deduc- tion can, consequently, be drawn from it. Sir Anthony Carlisle2 adopted.the opinion, that muscles become pale during contraction; but he offers no proof of it. The probability is, that he implicitly obeyed, in this respect, the dicta of his precursors, without observing the incongruity of such a supposition with his idea, that the absolute size of the muscle is augmented during contraction. The truth is, we have no evidence, that the colour of a muscle, or the quantity of blood circulating in it, is altered during contraction. Bichat,3 who adopted the opinion, that the blood is forced out during this state, relies chiefly upon the fact, known to every one, that in the operation of blood-letting from the arm the flow of blood is augmented by working the muscles; but the additional quantity expelled is properly ascribed by Dr. Bos- tock4 to the compression of the large venous trunks by the swelling out of the bellies of the muscles. The prevalent belief, amongst phy- siologists of. the present day, is, that there is no change of colour in the muscle during contraction. When the extremities of a muscle are made to approximate, the belly, of course, swells out; and would probably expand to such an extent, that the fasciculi, of which it is composed, would separate from each other, were it not for the areolar membrane and aponeuroses, with which they and the whole muscle are enveloped. The phenomena attendant upon the relaxation of a muscle are the reverse of those that accompany its contraction. The belly loses its rugous character; becomes soft, and the swelling subsides; the ends recede, and the organ is as it was prior to contraction. It is obvious, however, that after a part, as the arm, has been bent by the contrac- tion of appropriate muscles, simple relaxation would not be sufficient to restore it to its original position; for although the relaxation of a muscle has been regarded by Bichat and others to be, in part at least, 1 Art. Muskelbewegung, in Wagner's Handworterbuch der Physiologie, 15te Liefe- rung, S. 52 und 121, Braunschweig, 1846. 2 Op. citat., p. 27. 3 Anat. G-'neral., torn. iii. § 2. 4 Physiology, 3d edit., p. 94, Lond., 1836. PHENOMENA OF MUSCULAR CONTRACTION. 247 an active effort; and to consist in something more than the mere ces- sation of contraction, the evidence in favour of the view is extremely feeble and unsatisfactory. The arrangement of the muscular system is, in this, as in every other respect, admirable, and affords signal evi- dence of Omnipotent agency. The arm, as in the case selected above, has not only muscles to bend, but also to extend it; and, accordingly, when it has been bent, and it becomes necessary to extend it, the flexor muscles are relaxed and rest, while the extensors are thrown into action. This disposition of antagonist muscles prevails in almost every part of the frame, and will require notice presently. Muscles are not, however, the sole agents in replacing parts. Many elastic textures exist, which, when put upon the stretch by muscular contraction, have a tendency to return to their former condition, as soon as the extending cause is removed. Of this a good example occurs in the cartilages of prolongation, which unite the ribs to the sternum. During inspiration, these elastic bodies are extended ; and, by returning upon themselves, they become active agents of expira- tion, and tend to restore the chest to its unexpanded state. The production of the phenomena of muscular contraction is, so far as is known, unlike any physical process with which we are acquainted. It has, therefore, been considered essentially organic and vital; and, like other operations of the kind, will probably ever elude our re- searches. Yet here, as on every obscure subject, hypotheses have been innumerable; varying according to the fashionable systems of the day, or the views of the propounder. They, who formerly be- lieved that the muscular fibre is hollow, or vesicular, ascribed its con- traction to distension by the influx of "animal spirits" or of blood; and relaxation to the withdrawal of those. Such were the hypotheses of Borelli,1 Stuart,2 and others. Independently, however, of the ob- jection to these views, that we have no positive evidence of the exist- ence of such vesicles, it is obvious, that the explanation is defective, inasmuch as we have still to look to the cause that produces this mechanical influence. Again, how are we to account, under this hypothesis, for the surprising efforts of strength executed by muscles? The mechanical influence of animal or other spirits—granting for a moment their existence—might develope a certain degree of force; but how can we conceive them able, as in the case of the muscles in- serted into the foot, to develope such a force as to project the body from the ground? In all these cases, a new force is generated in the brain; and this, by acting on the muscular fibre, is the efficient cause of the contraction. Moreover, what an inconceivable amount of fluids would be necessary to produce the contraction of the various muscles, that are constantly in action; and what, it has been asked, becomes of these fluids when relaxation succeeds to contraction? Some have affirmed, that they are absorbed by the venous radicles; others, that they run off by the tendons; and others, again, that they become neutralized in the muscle, and communicate to it the greater size it' attains under exercise. These fantasies are too abortive to require comment. 1 De Motu Animalium, Lugd. Bat., 1710. 2 De Structura et Motu Musculari, Lond., 1738. 248 MUSCULAR MOTION. When chemical hypotheses were in fashion in medicine, physiology participated in them largely. At one time it was imagined, that an effervescence was excited in the muscle by the union of two sub- stances, one of which was of an acid, the other of an alkaline nature. Willis, Mayow, Keill,1 Bellini,2 &c, supported opinions of this kind* some ascribing the effervescence to a union of the nervous fluid with the arterial blood; others to a union of the particles of the muscular fibre with the nervous fluid; and others, to the disengagement of an elastic gas, primitively contained in the blood, and separated from it by the nervous spirits. It would, however, be unprofitable, as well as uninteresting, to repeat the different absurdities of this period—-so pro- lific in physical obscurities. Medicine has generally kept pace with physics, and where the latter science has been dark and enigmatical the former has been so likewise. In physiology, this is especially ap- parent; most of the natural philosophers of eminence having applied their doctrines in physics to the explanation of the different functions of the human frame. Newton, Leibnitz, and Des Cartes, were all spe- culative physiologists. The discovery of electricity gave occasion to its application to the topic in question; and it was imagined, that the fibres of the muscle might be disposed in such a manner as to form a kind of battery, capable of producing contraction by its explosions; and after the discovery of galvanic electricity, Valli3 attempted to ex- plain muscular contraction, by supposing that the muscles have an arrangement similar to that of the galvanic pile. Haller4 endeavoured to resolve the problem by his celebrated doctrine of irritability, which will engage attention hereafter. He conceived, that the muscles pos- sess, what he calls, a vis insita; and that their contraction is owing to the action of this force, excited by a stimulus, which stimulus is the nervous influx directed by volition. This, although a true doctrine we think, sheds no new light on the mysterious process. It is, in fact, cutting the Gordian knot. We should still have to explain the precise mode of action of the vis insita:5 but that it is not in any way derived from the nervous system will be shown when treating of Life. The hypothesis of Prochaska6 is entirely futile. He gratuitously presumes, that minute ramifications of arteries are every where con- nected with the ultimate muscular filaments, twining around them, and crossing them in all directions. AVrhen these vessels are rendered turgid by an influx of blood,—by passing among the filaments, they must, he conceives, bend the latter into a serpentine shape, and thus diminish their length, and that of the muscle likewise. Sir Gilbert Blane,7 again, throws out a conjecture,—deduced from experiments, in which he found that the actual bulk of a muscle is not changed during contraction, but that it gains in thickness exactly what it loses in length,—that this may be owing to the muscle being composed of 1 Tentamin. Medico-Physic, No. v., Lond., 1718. 8 Bostock, op. cit., p. 111. 3 Experiments in Animal Electricity, Lond., 1793. 4 Element. Physiol., xi. 214; and Oper. Minor., torn. i. 6 M. Hall, art. Irritability, Cyclop, of Anat. and Physiol., July, 1840. 6 De Carne Musculari, § ii., Vienn., 1778. 7 Op. citat. ELECTRICAL THEORY OF MUSCULAR CONTRACTION. 249 particles of an oblong shape; and that when the muscle is contracted, the long diameter of the particle is removed from a perpendicular to a transverse direction. But the same objection applies to this as to other hypotheses on the subject; that it is entirely gratuitous,—rest- ing on no histological observation whatever. Two views have been, perhaps, the most prevalent; one which con- siders muscular contraction to be a kind of combustion; another that it is produced by electricity. The former, which was originally pro- pounded by Girtanner,1 and zealously embraced by Dr. Beddoes, who was more celebrated for his enthusiasm than for the solidity of his opinions, has now few supporters. This hypothesis supposes, that muscular contraction depends upon the combustion of the combusti- ble elements of the muscle, hydrogen and carbon, by the oxygen of the arterial blood; the combustion being produced by the nervous influx, which acts in the manner of an electric spark;—at least, such is the view adopted by M. Richerand,2 one of the most fanciful of physiological speculators. Of course, we have neither direct nor ana- logical evidence of any such combustion, which, if it existed at all, ought to be sufficient, in a short space of time, to entirely consume the organs that furnish the elements. The idea is as unfounded as numerous others that have been entertained, and is worthy only of particular notice, from its being professed in one of the well-known works on physiological science. The second hypothesis refers muscular contraction to electricit}r. Attention has been already directed to the electroid or galvanoid cha- racter of the nervous agency; and we have some striking examples on record of the analogous effects produced by the physical and the vital fluid on the phenomena under consideration. It has been long known, that when nerves and muscles are exposed in a living animal, and brought into contact, contractions or convulsions occur in the latter. Galvani3 was the first to point this out. He decapitated a living frog; removed the fore-paws, and quickly skinned it. The spine was divided, so as to leave the spinal marrow communicating only with the hinder extremities by means of the lumbar nerves. He then took, in one hand, one of the thighs of the animal, and the vertebral column in the other, and bent the limb until the crural muscles touched the lumbar nerves. At the moment of contact the muscles were strongly con- vulsed. The experiment was repeated by Volta,4 Aldini,5 Pfaff,6 Hum- boldt,7 and others; and with like results. Aldini caused convulsions in the muscles by the contact of those organs with nerves, not only in the same frog, but in two different frogs. He adds, that he remarked them when he put the nerves of a frog in connexion with the muscular flesh of an ox recently killed.8 Humboldt made numerous experiments of this kind on frogs, and found convulsions supervene when he placed 1 Journ. de Physique, xxxvii. 139. 2 Elements of Physiology, § 163. 3 Mem. sull' Elettricita Animale, Bologn., 1797. 4 Memoria sull' Elettricita Animale, 1782. 5 Kssai Theoretique et Experiment, sur le Galvanisme, Paris, 1804. 6 TIeber thierische Electricitat und Reizbarkeit, Leipz., 1795. 7 Versuche uber die gereizte Muskel und Nervenfaser, Posen und Berlin, 1797. 8 Trait J complet de Physiologie de l'Homme, par Tiedemann, traduit par Jourdan, p. 559, Paris, 1837. 250 MUSCULAR MOTION. upon a dry plate of glass a posterior extremity whose crural nerves had been exposed, and touched the nerves and muscles with a piece of raw muscular flesh, insulated at the extremity of a stick of sealing-wax. Convulsions likewise occurred, when, instead of one piece of flesh, he used three different pieces to form the chain, one of which touched the nerve; the other the thigh, and the third the two others. The experi- ments were repeated by Ritter with similar results; but they were only found to succeed, when the frogs were in full vital activity,— especially in spring, after pairing; when the animal was of sufficient size, and its preparation for the experiment had been rapidly effected. From all these experiments it might be inferred, that parts of an animal may form galvanic chains, and produce a galvanic effect, which, independently of any mechanical excitation, may give rise to the con- traction of muscles. This excitation of electricity in chains of animal parts, M. Tiedemann thinks, ought not to be esteemed a vital act. Its effects only—the contractions excited in the muscles—are dependent on the vital condition of the muscles and nerves. He considers, that electricity, excited in chains of heterogeneous animal parts, may be modified and augmented by the organic or living forces; and that, moreover, in certain animals, organs exist, the arrangement of which is such as to excite electricity during their vital action as in the differ- ent kinds of electrical fishes; but in some experiments, instituted by M. Edwards,1 the effects above referred to were produced by touching a denuded nerve with a slender rod of silver, copper, zinc, lead, iron, gold, tin, or platinum, and drawing it along the nerve for the space of from a quarter to a third of an inch. He took care to employ metals of the greatest purity, as they were furnished him by the assayers of the mint. But it was not even necessary that the rod should be metal- lic: he succeeded with glass or horn. All metals, however, did not produce equally vigorous contractions. Iron and zinc were far less effective than the others; but no accurate scale could be formed of their respective powers. Much difference is found to exist, when electricity is employed, according as the nerve is insulated or not; for as the muscular fibre is a good conductor of electricity, if the nerve be not insulated, the elec- tricity is communicated to both nerve and muscle, and its effect is con- sequently diminished. It became, therefore, interesting to M. Edwards to discover, whether any difference would be observable, when one metal only was used, whether the nerve was insulated or not. In the experiments above referred to, the nerve was insulated by passing a strip of oiled silk beneath it. A comparison was now instituted be- tween an animal thus prepared, and another whose nerves instead of being insulated, rested on the subjacent flesh. He made use of small rods, with which he easily excited contractions when he drew them from above to below along the denuded portion of nerve that was sup- ported by the oiled silk; but he was unable to cause them when he passed the rod along the nerve of the other animal which was not insulated. His experiments were then made on two nerves of the same 1 Appendix to Edwards on the Influence of Physical Agents on Life,—Hodgkin and Fisher's translation, Lond., 1832. ELECTRICAL THEORY OF MUSCULAR CONTRACTION. 251 animal; and he found that after having vainly attempted to produce contractions by the contact of a nerve resting upon muscle, they could still be induced if the oiled silk were had recourse to; and he was able to command their alternate appearance and disappearance by using a non-conductor or a conductor for the support of the nerve. Somewhat surprised at these results, M. Edwards was stimulated to the investi- gation,—whether some degree of contraction might not be excited by touching the uninsulated nerve; and having remarked, that contrac- tions were most constantly produced in the insulated nerve by a quick and light touch, he adopted this method on an animal whose nerve was not insulated, and frequently obtained slight contractions. All his experiments on this subject seemed to prove, that, cceteris paribus, muscular contractions, produced by the contact of a solid body with a nerve, are much less considerable, or even wholly wanting, when the nerve, in place of being insulated, is in communication with a good conductor; and it would seem to follow, as a legitimate conclusion, that these contractions are dependent on electricity; facts, which it is well to bear in mind, in all experiments on animals where feeble elec- trical influences are employed.1 Galvanic electricity, it will be seen hereafter, is one of the great tests of muscular irritability, and is capable of occasioning contractions for some time after the death of the animal, as well as of maintaining, for a time, many of the phenomena peculiar to life. This is the reason why muscular contraction, excited by this nervous, electroid fluid, has been regarded as an electrical phenomenon. Much discrepancy has, however, arisen amongst the partisans of this opinion regarding its modus operandi. Rolando, we have seen, assimilates the cerebellum to an electro-motive apparatus, which furnishes the fluid that excites the muscles to contraction. Some have compared the spinal column to a voltaic pile, and have supposed the contraction of a muscle to be owing to an electric or galvanic shock. The views of MM. Dumas and Pre- vost2 are amongst the most striking. By a microscope, magnifying ten or twelve diameters, they first of all examined the manner in which the nerves are arranged in a muscle; and found, as has been already observed, that their ramifications always enter the muscle in a direction perpendicular to its fibres. They satisfied themselves, that none of the nerves really terminate in the muscle; but that the final ramifications embrace the fibres like a noose, and return to the trunk that furnishes them, or to one in its vicinity,—the nerve setting out from the anterior column of the spinal marrow, and returning to the posterior. On farther examining the muscles at the time of their contraction, the parallel fibres composing them were found, under the microscope, to bend in a zigzag manner, and to exhibit a number of regular undulations; such flexions forming angles, which varied according to the degree of con- traction, but were never under fifty degrees. The flexions, too, always occurred at the same parts of the fibre, and to them the shortening of the muscle was owing, as MM. Dumas and Prevost proved by calculat- 1 Coldstream, art. Animal Electricity, in Cyclop. Anat. and Physiol., P. ix., p. 93, Jan., 1837 ; and J. Miiller, Elements of Physiology, by Baly, p. 261, London, 1838. 2 Journal de Physiologie, torn. iii. 301; and Magendie, Precis, i. 220. 252 MUSCULAR MOTION. ing the angles. The angular points were always found to correspond to the parts where the small nervous filaments enter or pass from the muscles. They therefore believed, that these filaments, by their ap- proximation, induce contraction of the muscular fibre; and this approxi- mation they ascribed to a galvanic current running through them; which, as the fibres are parallel and in proximity, they thought, ought to cause them to attract each other, according to the law laid down by M. Ampere, that two currents attract each other when they move in the same direction. The living muscles are, consequently, regarded by them as galvanometers, and galvanometers of an extremely sensible kind, on account of the very minute distance and tenuity of the nervous filaments. They moreover affirm, that, by anatomical arrangement, the nerve is fixed in the muscle in the very position required for the proper performance of its function; and they esteem the fatty matter, which envelopes the nervous fibres, and which was discovered by M. Vauque- lin, as a means of insulation for preventing the electric fluid from passing from one fibre to another. Soon after hearing of M. Ampere's discovery of the attraction of electrical currents, it occurred to Dr. Roget,1 that it might be possible to render the attraction between the successive and parallel turns of heliacal or spiral wires very sensible, if the wires were sufficiently flexible and elastic; and, with the assistance of Dr. Faraday, his con- jecture was put to the test of experiment in the laboratory of the Royal Institution of London. A slender harpsichord-wire, bent into a helix, being placed in the voltaic circuit, instantly shortened itself whenever the electric stream was sent through it; but recovered its former dimen- sions the moment the current was intermitted. From this experiment it was supposed, that possibly some analogy might hereafter be found to exist between the phenomenon and the contraction of muscular fibre. The views of MM. Dumas and Prevost were altogether denied by M. Raspail,2 on the ground, that it is impossible to distinguish, by the best microscope, the ultimate muscular fibre from the small nervous fibrils by which those gentlemen consider them to be surrounded loopwis-,*. He farther affirmed, that the zigzag form is the necessary result of the method in which they performed their experiments, and is produced by the muscular fibre adhering to the glass on which it was placed. His own idea, founded on numerous observations, is, that the contraction of the fibre in length is'always occasioned by its extension in breadth under the influence of the vital principle. Independently, however, of M. Raspail's objection, the circumstance, that, in this mode of viewing the subject, the muscle itself is passive, and the nerve alone active, is a stumbling-block in the way of the views of MM. Dumas and PreV>st, and of Dr. Roget. It is proper, too, to remark, that M. Person3 was unable to detect any longitudinal galvanic currents in the nerves by the most sensible galvanometer; and that other stimuli besides galvanism are capable of exciting the muscular fibre to contraction. This we 1 Electro-Magnetism, p. 59, in 2d vol. of Nat. Philosophy, Library of Useful Know- ledge, London, 1832. 1 Chimie Organique, p. 212, Paris, 1833. 8 Journal de Physiologie, torn, x., Paris, 1830. ELECTRICAL THEORY OF MUSCULAR CONTRACTION. 253 see daily in experiments on the frog, by dropping salt on the denuded muscle. Prof. Miiller1 hence infers, that a nerve of motion, during life, and whilst its excitability or irritability continues, is so circumstanced, that whatever suddenly changes the relative condition of its molecules excites a contraction at the remote end of the muscle, and that elec- trical, chemical, and mechanical irritants are, in this respect, similarly situate. Interesting electro-physiological researches have been made by Pro- fessor Matteucci of Pisa, from which he has deduced the following results. First. Muscle is a better conductor of electricity than nerve; and nerve conducts better than brain. The conducting power of muscle may be taken as four times greater than that of brain or nerve. Secondly. In the muscles of living animals, as well as of those recently killed, an electric current exists, which is directed from the interior of each muscle to its surface. The duration of this muscular current corresponds with that of contractility; in cold-blooded animals, there- fore, it is greatest: in mammalia and birds very brief. Temperature has a considerable influence on the intensity of the current,—a small amount of electricity being developed in a cold medium; a larger one when the medium is moderately warm. Any circumstance that enfeebles the frogs (the animals experimented on) and deranges their general nutrition, diminishes the power of the muscles to generate electricity, as it likewise impairs the contractile force. The muscular current appears to be quite independent of the nervous system. It is unin- fluenced by narcotic poisons in moderate doses, but is destroyed by large doses, such as would kill the animal. The developement of this muscular current seems evidently to depend on the chemical action constantly taking place as an effect of the changes accompanying nutri- tion. Thirdly. In frogs an electric current exists which is distinct from the muscular current. It proceeds from the feet to the head, and is peculiar to batrachian reptiles. Fourthly. Singular results are obtained by applying electricity in various ways to nerves. On making experiments on the sciatic nerves of rabbits, he found that on closing the circuit of the direct electric current, or the current passing from the brain to the nerves, contractions in the muscles of the posterior limbs were produced; whilst opening this circuit was followed by marked signs of pain, with contraction of the muscles of the back, and feeble contractions of the posterior limbs. On closing the circuit of the inverse current, or that directed from the nerves to the brain, signs of pain, contractions of the muscles of the back, and feeble contractions of the posterior limbs were produced. On opening it, contractions of the posterior limbs followed.2 Similar electro-physiological researches have been made by M. Du- bois-Reymond in regard to the electric current, which accord with many of the results obtained by M. Matteucci. On comparing differ- 1 Art. Electricitiit (thierische), in Encyclopiid. WSrterb. der Medicin. Wissensch., x. 545, Berlin, 1834. 2 For an account of Matteucci's researches, see Todd and Bowman, Physiological Anatomy and Physiology of Man, vol. i., Lond., 1845, and, especially, Matteucci, Lec- tures on the Physical Phenomena of Living Beings, by Pereira, Amer. edit., pp. 176 and 224, Philad., 1848. 254 MUSCULAR MOTION. ent muscles with each other, he observed that the current was more intense when the muscle had to execute a greater mechanical action voluntary or involuntary. The muscular fasciculi of the heart, for example, which are not under the influence of the will, exhibited as energetic a current as the muscles of animal life, which are all voluu- tary; whilst the muscular fasciculi of the intestines, which have only feeble mechanical actions to execute, exhibited a very weak current. He found, however, contrary to Matteucci, that during muscular con- traction there was a remarkable diminution in the natural current. The numerous experiments which have been made by different ob- servers have as yet, led to no definite physical or physiological con- clusions. This is sufficiently shown by the resume of M. Pouillet who reported to the French Institute on the researches of M Dubois- Reymond. The cause, he concludes, of these organic currents is un- known:—it is probable that they do not result from any external chemical action, and it is not demonstrated, that they are induced by any internal. " It is a question to be solved; and, according as it may receive a positive or a negative solution, the ulterior consequences will assume very different characters."1 M. Dubois-Reymond found that an electric current exists in nerves, which in its manifestations greatly resembles the muscular current. With regard to the hypotheses which ascribe muscular contractility to the chemical composition of the fibre, and that which maintains, that the property is dependent upon the mechanical structure of the fibre, they are undeserving of citation, notwithstanding the respectability of the individuals who have written and experimented on the subject. They merely seem to show, that here, as in every case, a certain che- mical and mechanical constitution is necessary, in order that the vital operations, peculiar to the part, may be accomplished. But not only is it necessary, that the muscle shall possess a proper physical organization, it must, likewise, be endowed with a property essentially vital; in other words, with irritability or contractility. The cause of the ordinary contraction of muscles is, doubtless, the nervous influx; but if we materially alter the condition of the muscle, although the nervous influx may be properly transmitted to it, there will be no contraction. This applies to the living animal; but not apparently to the dead; for Valentin2 found, that after trying the femoral artery or vein, or dividing the sciatic nerve in frogs, the full strength of the muscle remained unaltered for several days,—in one case for twelve. We moreover find, that after a muscle has acted for some time, it be- comes fatigued, notwithstanding volition may regularly direct the nervous influx to it; and that it requires repose, before it is again capable of executing its functions. In the upper classes of animals, contractility remains for some time after dissolution; in the lower, especially in the amphibia, the period ' B.'raud, Manuel de Physiologie de l'Homme, p. 36, Paris, 1853. Ludwig Lehrbuch der Physiologie des Menschen, ler Bd., S. 316, Heidelb., 1853. See, on all this sub- ject, B.'clard, Traite Elementaire de Physiologie Humaine, p. 486, Paris 1855 and Carpenter, Principles of Human Physiology, Amer. edit., by Dr. F. G. Smith p. 434, Philad., 1855. ' 2 Lehrbuch der Physiologie des Menschen, ii. 176-92, Braunschweig 1844. ACTION OF GALVANISM ON MUSCLES. 255 during which it is evinced on the application of appropriate stimuli is much greater. From experiments on the bodies of executed criminals, M. Nysten found that irritability ceased in the following order of parts. The left ventricle of the heart first; the intestinal canal at the end of forty-five or fifty-five minutes; the urinary bladder at nearly the same time; the right ventricle after the lapse of an hour; the oesophagus at the end of an hour and a half; the iris a quarter of an hour later; the muscles of animal life somewhat later; and lastly, the auricles of the heart, especially the right, which, in one instance, under the influence of galvanism, contracted sixteen and a half hours after death. These results are singular; and the experiments merit repetition. It is, in- deed, strange, that muscles of organic life, apparently circumstanced so much alike, should vary so greatly in the length of time during which they retain their irritability. One of the most interesting of the many experiments that have been made on the bodies of criminals recently deceased, for the purpose of exhibiting the effects of galvanism or muscular irritability, is detailed by Dr. TJre.1 TJie subject was a murderer, named Clydesdale; a mid- dle-sized athletic man, about thirty years of age. He was suspended from the gallows nearly an hour, and made no convulsive struggle after he dropped. He was taken to the theatre of the Glasgow Uni- versity about ten minutes after he was cut down. His face had a per- fectly natural aspect, being neither livid nor tumefied; and there was no dislocation of the neck. In the first experiment, a large incision was made into the nape of the neck, close below the occiput, and the spinal marrow was brought into view. A considerable incision was made, at the same time, into the left hip, through the glutaeus maximus muscle, so as to expose the sciatic nerve;2 and a small cut was made in the heel; from neither of which any blood flowed. A pointed rod, connected with one end of a galvanic battery, of two hundred and seventy pairs of four-inch plates, was now placed in contact with the spinal marrow, whilst another rod, connected with the other end, was applied to the sciatic nerve. Every muscle of the body was imme- diately agitated with convulsive movements, resembling a violent shuddering from cold. The left side was most powerfully convulsed at each renewal of the electric contact. On removing the second rod from the hip to the heel, the knee being previously bent, the leg was thrown out with such violence as nearly to overturn one of the assist- ants, who in vain attempted to prevent its extension. In the next experiment, the left phrenic nerve was exposed at the outer edge of the sterno-thyroideus muscle. As this nerve is distri- buted to the diaphragm, and communicates with the heart through the 1 Art. Galvanism, in Diet, of Chemistry, Hare and Bache's Amer. edit., Philad., 1821. 2 It is not indispensable, in these experiments, to expose the nerve. The author has long known, that, in the case of the frog, it is needless ; and, in his experiments, he has been in the habit of acting under this knowledge. The experiments made on three criminals,—two of whom were executed at Philadelphia, and the third at Lan- caster, Pennsylvania—showed, indeed, that the elfect was even greater when the nerves were not exposed. It was found, too, to be more marked when the current was transmitted from the peripheral extremity of a nerve towards its centre. See Bell's Select Medical Library, for Oct., 1839; Amer. Journ. of Med. Sciences, May, 1840, p. 13; and Medical Examiner, Jan. 23d and 30th, 1841. 256 MUSCULAR MOTION. pneumogastric nerves, it was expected that, by transmitting the gal- vanic fluid along it, the respiratory process might be renewed. Ac- cordingly, a small incision having been made under the cartilage of the seventh rib, the point of one rod was brought into contact with the great head of the diaphragm, whilst that of the other was applied to the phrenic nerve in the neck. The diaphragm, which is a main agent in respiration, was instantly contracted, but with less force than was expected. " Satisfied," says Dr. Lire, " from ample experience on the living body, that more powerful effects can be produced in galvanic excitation by leaving the extreme communicating rods in close contact with the parts to be operated on, while the electric chain or circuit is completed by running the end of the wires along the top of the plates in the last trough of either pole, the other wire being steadily immersed in the last cell of the opposite pole, I had immediate recourse to this method. The success of it was truly wonderful. Full, nay laborious breathing instantly commenced. The chest heaved and fell; the belly was protruded and again collapsed, with the relaxing and retiring dia- phragm. This process was continued, without interruption, as long as I continued the electric discharges. In the judgment of many scien- tific gentlemen who witnessed the scene, this respiratory experiment was perhaps the most striking ever made with a philosophical appa- ratus. Let it also be remembered, that for full half an hour before this period, the body had been well-nigh drained of its blood, and the spinal marrow severely lacerated. No pulsation could be perceived, meanwhile, at the heart or wrist; but it may be supposed that but for the evacuation of the blood,—the essential stimulus of that organ,— this phenomenon might also have occurred." In a third experiment, the supra-orbital nerve was laid bare in the forehead. The one conducting rod being applied to it, and the other to the heel, most extraordinary grimaces were exhibited. Every mus- cle in the face was simultaneously thrown into fearful action. "Rage, horror, despair, anguish, and ghastly smiles, united their hideous ex- pression in the murderer's face, surpassing far the wildest representa- tion of a Fuseli or of a Kean." At this period, several of the spectators were forced to leave the room from terror or sickness; and one gentle- man fainted. The last experiment consisted in transmitting the electric power from the spinal marrow to the ulnar nerve as it passes by the internal con- dyle at the elbow; when the fingers moved nimbly, like those of a violin performer; and an assistant who tried to close the fist, found the hand open forcibly in spite of every effort to prevent it. When one rod was applied to a slight incision in the tip of the forefinger, the fist being previously clenched, the finger was instantly extended; and from the convulsive agitation of the arm, he seemed to point to the different spectators, some of whom thought he had come to life. The experiments of Dr. Ure have been several times repeated in this country on the bodies of criminals, and with analogous results.1 What important reflections are suggested by the perusal of such 1 Dunbar, in Baltimore Med. and Surg. Journal, i. 245, Bait., 1833, and the'journals referred to in the preceding pages. MUSCULAR SENSE. 257 cases! The great resemblance between the galvanic and the nervous fluids, and the absorbing idea, to the philanthropist, that galvanism might be found successful in resuscitating the apparently dead, in cases where other means may have failed! Unfortunately, it can rarely happen, that the means will be at hand, so as to be available; and, moreover, when the heart has ceased to beat for a few minutes, it is generally impracticable to cause it to resume its functions. An experiment, described by Dr. George Fordyce,1 exhibits the power of contractility resident in the tissues. He slightly scratched, with a needle, the inside of a heart removed from the body, when it contracted so strongly as to force the point of the needle deep into its substance. This experiment has been often cited for the purpose of showing, that the mechanical effect, in such cases, is infinitely greater than the mechanical cause producing it; and hence, as we have endea- voured already to show, that all mechanical explanations must be in- sufficient to account for the phenomena of muscular contraction. We are compelled, indeed, to infer, that a new force must always be gene- rated. In the year 1806, a cause was tried before the Court of Exchequer in England, in which a better knowledge of the properties of muscle might have led to a different result.2 According to the English law, where a man marries a woman seised of an estate of inheritance, and has, by her, issue born alive, which was capable of inheriting her estate,—in such case he shall, on the death of his wife, hold the lands for his life as tenant by the courtesy of England. It has, consequently, been a point of moment for the husband to show, that the child was born alive; and the law authorities have, with singular infelicity, at- tempted to define what shall be regarded evidences of this condition. According to Blackstone,3 " it must be born alive. Some have had a notion that it must be heard to cry, but that is a mistake. Crying, indeed, is the strongest evidence of its being born alive, but it is not the only evidence." According to Coke,4 " if it be born alive it is suf- ficient, though it be not heard to cry, for peradventure it may be born dumb.5 It must be proved that the issue was alive; for mortuus exitus non est exitus; so that the crying is but a proof that the child was born alive; and so is motion, stirring, and the like." This latitudinarian definition has given occasion to erroneous decisions, as in the trial alluded to, in which the jury agreed that the child was born alive; because, although, when immersed in a warm bath immediately after birth, it did not " cry, or move, or show any symptoms of life;" 3^et, according to the testimony of two females,—the nurse and the cook,— there twice appeared a twitching and tremulous motion of the lips; and this was sufficient to make it fall under Lord Coke's definition. It is manifest, that, granting such motidn to have actually occurred, it 1 Philos. Transact, for 1788, p. 25. 2 Taylor, Medical Jurisprudence, Amer. edit., by R. E. Griffith,p. 480, Philad., 1845. 5 Commentaries, B. ii. 127. 4 Institutes, 30, a. 6 It need scarcely be said that the deaf-dumb cry at the moment of birth the same as other children. The natural cry is effected by them as well as by the infant that possesses all its senses. It is the acquired voice, alone, which they are incapable of attaining. VOL. II.—17 258 MUSCULAR MOTION. was of itself totally insufficient to establish the existence of somatic life. We have seen, that on the application of stimuli, the"muscles of a body may be thrown into contraction for two hours after the cessation of respiration and circulation or after somatic death. Instead, there- fore, of referring the irritability to the existence, at the time, of soma- tic life, it must be regarded simply as an evidence of the persistence of molecular life in parts that had previously and recently formed part of a living whole. The contraction of a muscle is followed by its relaxation;—the fibres returning to their former condition. This appears to be a passive state; and to result from the suppression of the nervous influx by the will;—in other words, from the simple cessation of contraction. Some have, however, regarded both states to be active, but without proof. Barthez1 maintains, that the relaxation of a muscle is produced by a nervous action the reverse of that which occasions its contraction;— the will relaxing the muscles as well as contracting them. The muscle is the only part susceptible of contraction. The tendon conveys the force developed by it, passively, to the lever, which has to be moved. It has been ascertained by MM. Becquerel and Breschet,8 that a muscle during contraction augments in temperature. This increase is usually more than one degree of Fahrenheit; but at times when the exertion has been continued for five minutes,—as in the case of the biceps of the arm, in sawing wood,—it has been double that amount.3 Lastly, a sensation instructs the mind that a muscle has contracted, and this has given rise to the notion of a muscular sense, and a sensa- tion of motion:—Muskelsinn, Bewegungssinn or muscular sense of Gruithuisen, Lenhossek,4 Brown,•' Sir C. Bell,6 and other writers. It appears to be an internal sensation, produced by the muscle pressing on the sensible parts surrounding it, which convey the sensation to the brain. It is by this muscular sense that the brain learns to adapt the effort to the effect to be produced. Without it no precision could exist in the movements of the muscles, and every manual effort— whether of the artist or the mechanic—would be confused and disor- derly. The step, too, would be unsteady and insecure. " In chewing our food," says Dr. A. Combe,7 " in turning the eyes towards an object looked at, in raising the hand to the mouth, and, in fact, in every variety of muscular movement which we perform, we are guided by the muscular sense in proportioning the effect to the resistance to be overcome; and where this harmony is destroyed by disease, the extent of the service rendered us becomes more apparent. The shake of the arm and hand which we see in drunkards, and their consequent inca- pability of carrying the morsel directly to the mouth, are examples of what would be of daily occurrence, unless we were directed and assisted 1 Nouveaux Elemens de la Science de l'Homme, Paris, 1806. 2 Archiv. du Museum, torn. i. p. 402, and Annales des Sciences Naturelles, nouv. serie, iii. 272. 3 See on this subject Helmholtz, in Muller's Archiv., H. ii. S. 144, Berlin, 1848. * Rudolphi, Grundriss der Physiologie, 2ter Band, Lste Abtheil, S. 318, Berlin, 1823. 5 Lectures on Moral Philosophy. 6 The Hand, &c, Amer. edit., p. 145, Philad., 1833. ♦ 7 Principles of Physiology, 5th edit., p. 131, Edinb., 1836. FORCE OF MUSCULAR CONTRACTION. 259 by a muscular sense." It enables us to form ideas of force and resist- ance, by conveying to our minds a distinct idea of the effort required. The force or intensity of muscular contraction is dependent upon two causes,—the physical condition of the muscle, and the energy of the brain. A muscle, which is composed of large, firm fibres, will con- tract,—the energy of the brain being equal,—more forcibly than one with delicate, loose fibres. Volition generally determines the degree of power developed by the voluntary motions; and is accurately regu- lated so as to raise a weight of one pound or one hundred. We notice astonishing efforts of strength in those that are labouring, at the time, under strong cerebral excitement; mania, rage, delirium, &c. In such cases, the delicate muscles of the female are capable of contracting with a force far transcending that of the healthy male. The power of mus- cular contraction is, therefore, in a compound ratio with the strength of the organization of the muscle, and the degree of excitation of the brain. When both are considerable, the feats of strength surpass belief; and where both are small, the results are insignificant. The extensors of the knee and foot occasionally contract with so much vio- lence as to fracture the patella and tendo Achillis, respectively. The force, developed in the calf of the leg, must be great, .when a person stands on tiptoe with a burden on his head or shoulders; or when he projects his body from the soil, as in leaping. Rudolphi1 asserts, that he has seen a horse, which fractured its under-jaw by biting a piece of iron. It has been a question, whether the power of a muscle is greater or less at different degrees of contraction, the same stimulus being applied. To determine this, Schwann2 invented an apparatus, which should accurately measure the length of the muscle, and the weight it would balance by its contraction ; and from his experiments it appeared, that a uniform increase of force is attended with a nearly uniform increase in the length of the muscle. The explanation of this by Dr. Carpenter3 is probably correct;—that, as the observations of Mr. Bowman have clearly shown, there must be a considerable displacement of the con- stituents of every fibre during contraction, it is easy to understand, that the greater the contraction the more difficult must any farther contraction become. " If, between a magnet and a piece of iron attracted by it, there were interposed a spongy elastic tissue, the iron would cease to approach the magnet at a point, at which the attraction of the magnet would be balanced by the force needed to compress still farther the intermediate substance." We have a number of feats of surprising strength on record, several of which have been collected by Sir David Brewster.4 Of these, the cases of John Charles Van Eckeberg, who travelled through Europe under the appellation of Samson, and of Thomas Topham, are the most authentic and extraordinary. Dr. Desaguliers saw Topham, by the strength of his fingers, roll up a very strong and large pewter dish. He broke seven or eight short and strong pieces of tobacco pipe with the force of his middle finger, having laid them on his first and third 1 Op. cit., p. 303. 2 J. Miiller, Physiology, p. 903. 3 Human Physiology, § 394, Lond., 1842. 4 Letters on Natural Magic, Amer. edit., p. 222, New York, 1832. 260 MUSCULAR MOTION. fingers. Having thrust under his garter the bowl of a strong tobacco- pipe, his leg being bent, he broke it to pieces by the tendons of hia hams without altering the flexure of his knee. He broke another such bowl between his first and second fingers, by pressing his fingers to- gether sideways. He lifted a table six feet long—which had half a hundred weight hanging at the end of it—with his teeth, and held it in a horizontal position for a considerable time, the feet of the table resting against his knees. He took an iron kitchen poker, about a yard long, and three inches in circumference, and, holding it in his right hand, he struck upon his bare left arm, between the elbow and wrist, till he bent the poker nearly to a right angle. He took such another poker, and holding the ends of it in his hands, and the middle against the back of his neck, he brought both ends of it together before him; and afterwards pulled it nearly straight again. He broke a rope about two inches in circumference, which was in part wound about a cylinder of four inches in diameter, having fastened the other end of it to straps that went over his shoulders. Lastly, he lifted a rolling- stone, eight hundred pounds in weight, with his hands only, standing in a frame above it, and taking hold of a chain that was fastened to it. An equally remarkable example is given by a recent well-known traveller1 as having been witnessed by him in Paris. In the Place du Carrousel, a large coarse French woman made the following exhibition, in the presence of a great crowd of spectators. A rough block of stone, weighing more than three hundred pounds, and which two men could barely lift from the ground, was fastened round with several turns of rope. The long black hair of the woman, which was divided into seven traces, tightly platted and fastened at the end, was then brought down, and attached to these ropes, whilst the woman herself bent her head back towards the stone for the purpose of admitting of the traces being fastened. When this was done, she slowly rose to her erect position, lifting the stone entirely from the ground, its weight being borne by the seven traces of her hair, and the pressure resting wholly on her scalp. She then began to turn herself slowly round, swinging the stone just fastened to her hair, until, by the progressively increas- ing motion, she twirled round as rapidly as the spinning dervishes, or an opera dancer in a pirouette, but for a longer period,—the stone all this while going out farther and farther from her person till it swung round almost horizontally, and with a velocity that made it fearful to look upon, relaxing gradually from the highest point of motion till it rested at her feet. It was then loosened from the hair and the cords; and her next feat was to place two rush-bottomed chairs at a distance of about four feet and a half from each other, when she placed her head on one, and her heels on the other, thus lying horizontally between the two, without any support for her back or loins in the centre, and neither her head nor her heels being more than six inches from the outer edge of the chairs. Whilst in this condition, two men were in- vited to come from the crowd and lift up the stone, so as to place it on her stomach. Two persons came from amongst the bystanders, and one of them not being a strong man, they were unable to lift it, when 1 J. S. Buckingham, Travels in France, Piedmont, &c, ii. 63, Lond., 1849. DURATION OF MUSCULAR CONTRACTION. 261 a third came to their assistance; but not till after at least twenty per- sons had tried to lift the stone a little from the ground, to be assured it was not hollow, and that there was no deception, and each had failed to lift it half an inch from where it stood. The three men, however, raised it up, and placed it on the woman's stomach, as she lay in this horizontal position; when another person, at her request, placed a smaller stone on the large one, and with a heavy iron sledge-hammer broke it into twenty pieces. All this occupied about a quarter of an hour, during the whole of which time the woman evinced no appear- ance of shrinking; and in conversing with her after she rose there was not the slightest evidence of any inconvenience being felt by her from the exertion. That much depends upon physical organization, as regards the force of muscular contraction, is evinced by the fact of the great difference in the various races of mankind. On our own continent, numerous opportunities have occurred for witnessing the inferiority, in strength, of the aborigines to the white settlers. Peron1 took with him, in his voyage round the world, one of Regnier's dynamometers, which indicate the relative force of men and animals. He directed his attention to the strength of the arms and loins, making trial on several individuals of different nations; twelve natives of Van Diemen's Land; seventeen of New Holland; fifty-six of the island of Timor; seventeen Frenchmen belonging to the expedition, and fourteen Englishmen in the colony of New South Wales. The following was the mean result:— STRENGTH. Of the Arms. Of the Loins. Kilogrammes* Myriagramm.es. 1. Van Diemen's Land, . . . . . 50*6 2. New Holland,......50-8 10-2 3. Timor,.......58-7 11-6 4. French,.......69-2 15-2 5. English,.......71-4 16-3 The highest numbers, in the first and second divisions, were respect- ively 60 and 62; the lowest in the fifth, 63 ; in the highest 83, for the strength of the arms. In the power of the loins, the highest amongst the New Hollanders was 13 ; the lowest of the English, 12*7.3 The force of muscular contraction is also largely increased by the proper exercise of the muscles. Hence the utility of the ancient gym- nasia. In early times, muscular energy commanded respect and ad- miration. It was the safeguard of individuals and families, and the protection of nations; and it was esteemed a matter of national policy to encourage its acquisition. In modern times, the invention of gun- powder having altered the system of warfare, and given to skill the 1 Voyage, &c, torn. i. chap. xx. p. 446; and t. ii. p. 461; and Lawrence's Lectures on Physiology, &c, p. 404, Lond., 1819. 2 The approximate value of a kilogramme is about two pounds avoirdupois:—of a myriagramme about twenty. 3 See Quetelet, Sur l'Homme, &c, Paris, 1835, or English edit., by Dr. R. Knox, p. 67, Edinburgh, 1842. Prof. Forbes, of Edinburgh, in London and Edinburgh Phil. Magazine, for March, 1837, p. 197 ; and in Dunglison's American Med. Intelligencer, for May 15, 1837, p. 74; in which are detailed experiments on the weight, height, and strength of above eight hundred individuals, natives of England, Scotland, Ireland, and Belgium. 262 MUSCULAR MOTION. superiority which strength communicated in personal combats, insti- tutions for the developement of the muscular system have been aban- doned, until of comparatively late years. They afford us striking examples of the value of muscular exertion, not only in giving energy and pliancy to the frame, but as a means of preserving health. The mean effect of the labour of an active man, working to the greatest possible advantage, and without impediment, is usually esti- mated to be sufficient to raise ten pounds, ten feet in a second for ten hours in a day; or to raise one hundred pounds, which is the weight of twelve wine gallons of water, one foot in a second, or thirty-six thousand feet in a day; or three millions, six hundred thousand pounds, or four hundred and thirty-two thousand gallons, one foot in a day. Dr. Desaguliers affirms, that the weakest men who are in health, and not too fat, lift about one hundred and twenty-five pounds; and the strongest of ordinary men four hundred pounds. Topham lifted eight hundred. The daily work of a horse is estimated to be equal to that of five or six men. In insects, the force of muscular contraction appears to be greater in proportion to their size than in any other animals. The Lucanus cervus or Stag Beetle has been known to gnaw a hole of an inch dia- meter in the side of an iron canister in which it had been confined, and many striking examples of a similar kind are given hereafter under the head of Leaping. In the duration of muscular contraction we notice considerable dif- ference between the voluntary and involuntary muscles; the latter being much more rapid and alternating. The same remark applies to the voluntary muscles, when excited by another stimulus than that of the will. Contraction, excited by volition, can be maintained for a considerable time: of this we have examples in bearing a burden; the act of standing; holding the arm extended from the body, &c. In all these cases, the contractility of the muscles is sooner or later ex- hausted ; fatigue is experienced; and it becomes necessary to give them rest; the power of contractility, however, is soon resumed, and they can be again put in action. This law of intermission in muscu- lar action appears absolute;—relaxation being followed by contrac- tion, in every organ, from the commencement of life until its final cessation. The intermission, has, indeed, by many physiologists, been held to prevail—to a slight extent only, it is true—during what we are in the habit of considering continuous muscular contraction. In proof of this, they cite the fact, that when we put the tip of the finger into the meatus auditorius externus, we hear a kind of buzzing or humming, which does not occur when an inert body is introduced.' There are, however, other actions going on in the finger besides mus- cular contraction; and the buzzing might, with as much propriety, be referred to the noise made by the progression of fluids in the vessels, as to the oscillations of muscular contraction and relaxation. We know not, in truth, whence the sound immediately proceeds. Dr. Brown-Sequard2 found, that when he kept his forearm extended 1 Wollaston, in Philosoph. Transact, for 1810, p. 2. 2 Medical Examiner, July, 1852, p. 428. VELOCITY OF MUSCULAR CONTRACTION. 263 with a weight in one of his hands, and felt his power to continue it so was lost, if an assistant applied the wires of an electro-magnetic ma- chine to his shoulder and forearm so as to excite the biceps and some other muscles, he could maintain the forearm nearly in the same posi- tion for several minutes longer; whence he concludes, that it is the action of a part of the brain, and not of the muscles which is deficient when the will is unable to maintain a permanent contraction of them. In the velocity of muscular contraction, much difference exists, ac- cording to the stimulus which sets it in action. If we apply galvan- ism to a muscle, we find the contractions at first exceedingly rapid; but they become progressively feebler, and require a stronger stimu- lus, until their irritability appears to be exhausted. Irritating the nerve in these cases is found to produce a greater effect, than when the stimulus is applied directly to the muscle. The velocity of volun- tary contraction is, of course, variable, being regulated entirely by the will. We have, in various classes of the animal kingdom, remarkable instances of this velocity. The motions of the racer, greyhound, prac- tised runner, the fingers in playing on musical instruments—as the violin, flute, piano-forte—and in writing; of the voice in enunciation, and of the upper and lower limbs in striking, leaping, and kicking, convey a general notion of this rapidity of contraction; and how nicely, in many cases, it must be regulated by volition. The fleetest race-horse on record was capable of going, for a short distance, at the rate of a mile per minute; yet this is trifling, when compared with the velocity of certain birds, which can, with facility, wheel round and round the most rapid racer in circles of immense diameters,—and with that of numerous small insects, which accompany us, with apparent facility, when we travel with great rapidity, even against the wind. It has frequently excited surprise, how porpoises—animated pro- pellers—can sail around vessels in rapid motion, and how migratory birds can support themselves so long upon the wing as to reach the country of their migration; and, at the same time, live without food during their aerial voyage. The difficulties of the subject have impelled many to deny the fact of their migration, and excited others to form extravagant theories to account for the preservation of the birds during the winter months; but if we attend to their exces- sive velocity, the difficulties, in a great measure, vanish. " Nothing," says Wilson,1 "is more common in Pennsylvania than to see large flocks of the bluebirds, in spring and fall, passing at considerable heights in the air,'—from the south in the former, from the north in the latter season. The Bermudas are said to be six hundred miles from the nearest part of the continent. This may seem an extraordi- nary flight for so small a bird; but it is a fact that it is performed. If we suppose the bluebird to fly only at the rate of a mile a minute, which is less than I have actually ascertained them to do over land, ten or twelve hours would be sufficient to accomplish the journey." Montagu, a celebrated ornithologist, estimates the rapidity with which hawks and many other birds occasionally fly to be not less than one hundred and fifty miles an hour; and that one hundred miles per hour 1 American Ornithology, ii. 178. 264 MUSCULAR MOTION. is certaiuly not beyond a fail computation for the continuance of their migration. Major Cartwright, on the coast of Labrador, found by re- peated observations, that the flight of the eider duck is at the rate of ninety miles an hour; yet it has not been esteemed very remarkable for its swiftness. Sir George Cayley computes the rate of flight of the common crow at nearly twenty-five miles an hour. Spallanzani found that of the swallow about ninety-two miles an hour; and he conjec- tures, that the velocity of the swift is nearly three times greater. A falcon belonging to Henry IV. of France escaped from Fontainbleau, and was in twenty-four hours afterwards at Malta,—a distance com- puted to be not less than one thousand three hundred and fifty miles, making a velocity of nearly fifty-seven miles an hour, supposing the falcon to have been on the wing the whole time; but, as such birds never fly by night, if we allow the day to have been at the longest, his flight was perhaps at the rate of seventy-five miles per hour. It is not probable, however, as Montagu observes, that it had either so many hours of light in the twenty-four to perform its journey, or that it was retaken at the moment of its arrival.1 A society of pigeon- fanciers from Antwerp despatched ninety pigeons from Paris, the first of which returned in four hours and a half, at a rate of nearly fifty miles an hour. Out of one hundred and ten pigeons, carried from Brussels to London in the summer of 1830, and let fly from London on July 19th, at a quarter before nine A. M., one reached Antwerp, one hundred and eighty-six miles distant, at eighteen minutes past two, or in five and a half hours,—being at the rate of nearly thirty- four miles an hour. In another case, one went from London to Maes- tricht, two hundred and sixty miles, in six and a quarter hours. In January, 1831, two pigeons, carried from Liskeard to London, were let loose in London. One reached Liskeard, two hundred and twenty miles distant, in six hours; the other in a quarter of an hour more.' There is an instance of the migratory or passenger pigeon,—Columba migratoria of Wilson—having been shot in Fifeshire, in Scotland. It was the first ever seen in Great Britain, and had been forced over, it was imagined, by unusually strong westerly gales.3 The velocity of the contraction of the muscles of the wings, in these rapid flights, is incalculable. The possible velocity, in any case, must be greatly dependent upon habit. Nothing can be more awkward than the first attempts at writing, drawing, playing on musical instru- ments, or performing any mechanical process in the arts; and what a contrast is afforded by the astonishing celerity, which practice never fails to confer in any one of those varieties of muscular contraction! In running, leaping, wrestling, dancing, or any other motion of the body, one person can execute with facility what another, with equally favourable original powers, cannot effect, because he has not previously and frequently made the attempt. Prize-fighting affords an instance of this kind of muscular velocity and precision acquired by habit,— the practised boxer being able to inflict his blow and return his arm to the guard so quickly as almost to elude the sight. By considering 1 Fleming's Philosophy of Zoology, ii. 42, Edinb., 1822. 2 Turner's History of the World, Amer. edit., i. 2^9, New York, 1832. 3 New Monthly Magazine for 1826. ELEMENTARY PRINCIPLES OF MECHANICS. 265 the muscular motions, employed in transporting the body of the fleetest horse, Haller concluded, that the elevation of the leg must have been performed in ^th of a second. He calculates, that the rectus femoris,— the large muscle which is attached to the knee-pan and extends the lee,—is shortened three inches in the ^gth of a second in the most rapid movements of man. But, he adds, the quickest motions are executed by the muscles concerned in the articulation of the voice. He himself, in one experiment, pronounced fifteen hundred letters in a minute; and as the relaxation of a muscle occupies as much time as its contraction, the contraction of a muscle, in pronouncing one of these letters, must have been executed in 30'ufith Par^ 01>a minute; and in much less time in some letters, which require repeated contractions of the same muscle or muscles as r. If the tremors, that occur in the pronunciation of this letter, be estimated at ten, the muscles concerned in it must have contracted in Haller's experiment, in 3^no(5tn Par* °f a minute.1 It has been calculated, that all the tones of which the human voice is capable are produced by a variation of not more than one-fifth of an inch in the length of the vocal cords; and that in man the variation required to pass from one interval to another will not be more than T25^th of an inch. These cases are, however, far exceeded by the rapidity of the vibrations of the wings of insects, which can be estimated from the musical tone they induce, experiment having shown the number of vibrations required to produce any given note. The vibrations of their wings have thus been found to amount to several thousands per second. It has been the opinion of many physiologists and metaphysicians, that muscular contraction is only directed by volition within certain limits of velocity; and that when it exceeds a certain velocity it de- pends upon habit. The effects of volition have, in this respect, been divided into the immediate and remote. Of the first we have examples in the formation of certain vocal and articulate sounds; and in certain motions of the joints, as in the production of voice, speech, and loco- motion. In the second, those actions are included which we conceive to be within our power, but in which we think of the end to be ob- tained, without attending to the mechanical means. " In learning a language, for example," says Dr. Bostock,2 " we begin by imitating the pronunciation of the words, and use a direct effort to put the organs of speech in the proper form. By degrees, however, we become fami- liar with this part of the operation, and think only of the words that are to be employed, or even the meaning that is to be conveyed by them. In learning music, we begin by imitating particular motions of the fingers, but at length the fingers are disregarded, and we only con- sider what sounds will follow from certain notes, without thinking of the mechanical way in which the notes are produced." In these, how- ever, and in all other cases that can be brought forward, it is difficult to conceive how the effect can be produced without the agency of vo- lition,—obscure it is true, but still in action. The case of reading is often assumed, as confirming the view that invokes habit; yet, if a letter be inverted,, we immediately detect it; and although, by habit, 1 Elementa Physiologic, &c, lib. xi. 2, Lausan., 1757-1766. 2 Physiology, edit, cit., p. 774, Lond., 1836. 266 MUSCULAR MOTION. we may have acquired extreme facility in playing the notes of a rapid musical movement, no doubt, we think, ought to exist, that an effort of volition is exerted on each note composing it,—inasmuch as there is no natural sequence of sounds; and hence there appears no cogent reason, why one should follow rather than another, unless a controllin°* effort of the will were exerted. With regard to the extent of muscular contraction, this must of course be partly regulated by volition; but it is also greatly owing to the length of the muscular fibres. The greater the length, of course the greater the decurtation during contraction. We shall see, likewise, that this depends upon the kind of lever, which the bone forms, and the distance at which the muscle is inserted from the joint or fulcrum. Before passing to the examination of special movements, it will he necessary to consider briefly certain elementary principles of mechanics, most of which are materially concerned in every explanation, and with- out some knowledge of which such explanation would, of course, be obscure or unintelligible. Were we, as M. Magendie1 has remarked, to investigate narrowly every motion of the body, we should find the applicability of almost all the laws of mechanics to them. If we take a rod of wood or metal, of uniform matter throughout, and support it at the middle, either like the beam of a balance, or on a pointed body, we find, that the two ends accurately balance each other; and if we add weights at corre- sponding parts of each arm of the beam, that is, at parts equidistant from the point of suspension, the balance will still be maintained. The point by which the beam is suspended, or at which it is equilibrious, is called its centre of gravity; and, in every mass of matter, there is a point of this kind, about which all the parts balance or are equilibrious; or, in other words, they have all a centre of gravity or inertia. The centre of gravity, in a mass of regular form and uniform substance, as in the parallelograms, Figs. 355 and 356, is easily determined, inasmuch as it must necessarily occupy the centre c; but in bodies that are irregular, either as regards den- sity or form, it has to be determined by rules of calcu- lation, to be found in all works on physics; but which it is unne- cessary to adduce here. The nearer the centre of gravity is to the soil on which the body rests, the more stable is the equilibrium. In order that the Figures 355 and 356 shall be overturned from left to right, the whole mass must turn upon e as upon a pivot; the centre of gravity describing the curve c b, and the whole mass being lifted in the same degree. In Fig. 355, the curve is nearly horizontal, owing to the narrowness of the base and the height of the Centre of Gravity. centre of gravity. In Fig. 356, on the other hand, whose base is broad and the centre of gravity Centre of Gravity. Fig. 356. 1 Precis, &c, edit, cit., i. 276. ELEMENTARY PRINCIPLES OF MECHANICS. 267 low, the curve rises considerably; the resistance to overturning is con- sequently nearly equal to the whole weight of the body, and the equi- librium necessarily firm. The condition of equilibrium of a body resting upon a plane is such, that a perpendicular, let fall from the centre of gravity, shall fall within the points by which it touches the plane. This per- pendicular is called vertical line or line of direction, being that in which it tends naturally to descend to the earth; and the space comprised between the points by which the body touches the soil is called base of sustentation. We can now understand, why a wagon, loaded with heavy goods, may pass with safety along a sloping road; whilst, if it be loaded to a greater height with a lighter substance, it may be readily overturned. When the wagon is loaded with metal, the centre of gravity is low, as at c, Fig. 357; the vertical line c p falls considerably within the base of >n iibriuui. qm" sustentation; and the centre describes a rising path; bat in the other case the centre is thrown higher, to a; and the vertical line falls very near the wheel, or on the outside of it, and consequently of the base, whilst the centre describes a falling path. Of two hollow columns, formed of an equal quantity of the same matter, and of the same height, that which has the largest cavity will be the stronger; and of two columns of the same diameter, but of dif- ferent heights, the higher will be the weaker. All bodies tend to continue in the state of motion or of rest, so as to render force necessary to change their state. This property is called the inertia of motion, or of rest, as the case may be. When a carriage is about to be moved by horses, considerable effort is necessary to over- come the inertia of rest; but if it moves with velocity, effort is required to arrest it, or to overcome the inertia of motion. We can thus under- stand why, if a horse start unexpectedly, it is apt to get rid of its burden; and why an unpractised rider is projected over his horse's head if it stops suddenly. In the former case, the inertia of rest is the cause of his being thrown; in the latter, the inertia of motion. The danger of attempting to leap from a carriage, when the horses have taken fright, is thus rendered apparent. The traveller has acquired the same velocity as the vehicle; and if he leaps from it, he is thrown to the ground with that velocity; thus incurring an almost certain in- jury to avoid one remotely contingent. The force, momentum, or quantity of motion in a body is measured by the velocity, multiplied into the quantity of matter. A cannon-ball, for example, may be rolled so gently against a man's leg, as not even to bruise it; but if it be projected by means of gunpowder, it may mow down a dense column of men, or penetrate the most solid substance. If a man be running, and strike against another who is standing, a certain shock is received by both; but if both be running in opposite directions with the same velocity, the shock will be doubled. The subject of the direction of forces applies to most cases of mus- cular movement. Where only one force acts upon a body, the body proceeds in the direction in which the force is exerted, as in the case 268 MUSCULAR MOTION. of a bullet fired from a gun; but if two or more forces act upon it at the same time, the direction of its motion will be a middle course be- tween the direction of the separate forces. ' This course is called the resulting direction, that is, resulting from the composition of the forces. Let us suppose two forces a T and b T in Fig. 358, acting upon the body T, which may be regarded as the ten- don of a muscle, and the two forces as the power developed by muscular fibres holding the same situation; the result will be the same, whether they act together or in succession. For example, if the force a T is sufficient to draw T to a, and immediately afterwards the force b T be exerted upon it, the tendon will be at c, the place towards which it would be drawn by the simultaneous action of the two forces or fibres. If, therefore, we complete the figure by drawing a c equal and parallel to T b, and c b equal and parallel to a T, we have the parallelogram of forces, as it is called, of which the diagonal shows the resultant of the forces, and the course of the body on which they act. In the case, assumed in Fig. 358, the forces are equal. If not, the-parallelogram may result as in Fig. btfO; in which T c will, again, be the resultant of the forces a T and T b, or we may have the arrange- ment in Fig. 359. By these parallelograms, we are enabled, also, to resolve the resultant into its component forces. Suppose, for example, we desire to know the quan- tity of force in the resultant, T c, Fig. 358, which is capable of acting in the directions T a and T b; it is only necessary to draw, from the point c, c a parallel to T b, and c b parallel to T a; and the lines T a and T b, cut off by these, will be the forces into which it may be resolved. The same applies to Figs. 359 and 360, and to every other of the kind. Friction is the resistance necessary to be overcome in making one body slide over another; and adhesion the force, which unites two polished bodies when applied to each other,—a force, which is mea- sured by the perpendicular effort necessary for separating the two bodies. The more polished the Composition of Forces. Fig. 359. Composition of Forces. Fig. 360. Composition of Forces. surfaces in contact, the greater is the adhesion, and the less the fric- tion; so that where the object is merely to facilitate the sliding of one surface over another, it will be always advantageous to make the surfaces polished, or to put a liquid between them. A beam or rod of any kind, resting at one part on a prop or support, which thus becomes its ELEMENTARY PRINCIPLES OF MECHANICS. 269 Lever of the first kind. centre of motion, is a lever. The ten inch beam, P W, Fig. 361, is a lever, of which F may be considered the prop or fulcrum; P, the part at which the power is applied, and W, the point of application of the weight or resistance. In every lever we distinguish three points:—the fulcrum Kpower, and resistance; and, ac- Fig. 361. cording to the rela- tive position of these points, the lever is said to be of the first, second, or third kind. In a lever of the first kind, the fulcrum is between the resistance and power, as in Fig. 361; F being the fulcrum on which the beam rests and turns; P, the power; and W, the weight or resistance. We have numerous familiar examples of this lever; the crowbar in elevating a weight; the handle of a pump; a pair of scales ; a steelyard, &c. A lever of the second kind has the resistance W, Fig. 362, between the power P and the fulcrum F; the fulcrum and power occupying each one extremity. The rudder of a ship, a wheelbar- row, and nut-crack- ers, are varieties of this kind of lever. In a lever of the third kind, the power P is between the resistance W, and the fulcrum F, Fig. 363; the resistance and the fulcrum occupying each one extremity of the lever. In the last two levers, the weight and the power change places. Tongs and shears are levers of this kind ; also, a long ladder raised against a wall by the efforts of a man: here the fulcrum is at the part of the ladder which rests on the ground; the power is exerted by the man; and the resistance is the ladder above him. In all levers are distinguished,—the arm of the power and the arm of the resistance. The former is the distance comprised between the power and the fulcrum, P F, Figs. 361, 362, and 363; and the latter is the dis- tance W F, or that be- Fig. 363. Fig. 362. Lever of the second kind. tween the weight and the fulcrum. When, in the lever of the first kind, the fulcrum oc- cupies the middle, the lever is said to have equal arms; but if it be nearer the power or the resistance, it is said to be a lever with unequal arms. W* -rplll;.....iililircTfiTraiilHIllllll'lllllllllll * I3 lll'lll'l.....HIIHIIH.....IIMIIIIIIIIIIIIIIIIIIlllllllllllllllllillliill Lever of the third kind. 270 MUSCULAR MOTION. The length of the arm of the lever gives more or less advantage to the power, or the resistance, as the case may be. In a lever of the first kind, with equal arms, complete equilibrium would exist, provided the beam were alike in every other respect. But if the arm of the power be longer than that of the resistance, the resistance is to the power as the length of the arm of the power is to that of the arm of the resist- ance; so that if the former be double or triple the latter, the power need only be one-half or one-third of the resistance, in order that the two forces may be in equilibrium. A reference to the figures will exhibit this in a clear light. The three levers are all presumed to be of equal substance throughout, and to be ten inches, or ten feet in length. The arm of the power, in Fig. 361, is the distance P F, equal to eight of those divisions; whilst that of the resistance is W F, equal to two of them. The advantage of the former over the latter is, consequently, in the proportion of eight to two, or as four to one; in other words, the power need only be one-fourth of the resistance, in order that the two forces may be equilibrious. In the lever of the second kind, the pro- portion of the arm P F of the power is to that of the resistance, W F, as ten—the whole length of the lever—to two; or five to one; whilst, in the lever of the third kind, it is as two to ten, or as one to five; in other words, to be equilibrious, the power must be five times greater than the resistance. We see, therefore, that in the lever of the second kind, the arm of the power must necessarily be longer than that of the resistance, since the power and the fulcrum are separated from each other by the whole length of the lever; hence this kind of lever must always be advantageous to the power; whilst the lever of the third kind, for like reasons, must always be unfavourable to it, seeing that the arm of the resistance is the whole length of the lever, and, there- fore, necessarily greater than that of the power. It can now be understood why a lever of the first kind should be most favourable to equilibrium; one of the second for overcoming resistance; and one of the third for rapidity and extent of motion: for whilst, in Fig. 363, the power is moving through the minute arc at P, in order that the lever may assume the position indicated by the dotted lines F W, the weight or resistance is moving through the much more considerable space W w. The direction in which the power is inserted into the lever likewise demands notice. When perpendicular to the lever, it acts with the greatest advantage,—the whole of the force developed being employed in surmounting the resistance; whilst if inserted obliquely a part of the force is employed in tending to move the lever in its own direction; and this part is destroyed by the resistance of the fulcrum. Lastly: the general principles of equilibrium in levers consist in this;—that whatever may be the direction in which the power and re- sistance are acting, they must always be to one another inversely as the perpendiculars drawn from the fulcrum to their lines of direction. In Fig. 363, for example, the line of direction of the upper weight is W w; that of the power Pp; and, to keep the lever in equilibrium in this position, the forces must be to one another inversely as F w to ¥ p. In applying these mechanical principles to the illustration of muscu- lar motion, we must, in the first place, regard each movable bone as a APPLICATION OF MECHANICAL PRINCIPLES. 271 lever, whose fulcrum or centre of motion is in its joint; the powrer at the insertion of the muscle; and the resistance in its own weight and that of the parts which it supports. In different parts of the skeleton we find the three kinds of levers. Each of the vertebrae of the back forms, with the one immediately beneath it, a lever of the first kind,— the fulcrum being seated in the middle of the under surface of the body of the vertebra. The foot, when we stand upon the toe, is a lever of the second kind,—the fulcrum being in the part of the toes resting upon the soil; the power in the muscles inserted into the heel, and the resist- ance in the ankle joint, on which the whole weight of the body rests. Of levers of the third kind we have numerous instances; of which the deltoid, to be described presently, is one. In this, as in other cases, the applicability of the principle, laid down regarding the arms of the lever, &c., is seen, and we find, that, in the generality of cases, the power is inserted into the lever so near to the fulcrum, that considerable force must be exerted to raise an inconsiderable weight;—that so far, conse- quently, mechanical disadvantage results; but such disadvantage enters into the economy of nature, and is attended with so many valuable con- comitants as to compensate richly for the expense of power. Some of these causes, that tend.to diminish the effect of the forces, we shall first consider, and afterwards attempt to show the advantages resulting from these and similar arrangements in effecting the wonderful, complicate operations of the muscular system. In elucidation of this subject, we may take, with Haller,1 the case of the deltoid—the large muscle, which constitutes the fleshy mass on the top of the arm, and whose office it is to raise the upper extremity. Let W F, Fig. 364, represent the os humeri, with a weight W at the elbow, to be raised by the deltoid D. The fulcrum F is necessarily, in this case, in the shoulder-joint; and the muscle D is inserted much nearer to the fulcrum than to the end of the bone on which the weight rests; the arm of the power P F—(suppos- ing, for a moment, that it is acting at Fig- 364. this part with every advantage, which we shall see presently it is not)—is, consequently much shorter than that of the resistance W F, which, as in all levers of the third kind, occupies the whole length of the lever. In estimating the effect from this cause alone upon the power to be exerted by the deltoid, we may suppose, that the arm of the power is to that of the Action of the Deltoid. resistance as 1 to 3;—the deltoid being inserted into the humerus about one-third down. Now, if we raise a weight of fifty-five pounds in this way, and add five pounds for the weight of the limb—which may be conceived to act entirely at the end of the bone—the power, which the deltoid must exert to produce the effect, is equal not to sixty pounds, but to three times sixty or one hundred and eighty pounds. 1 Eleuienta Physiologiae, lib. xi. 2. 272 MUSCULAR MOTION. Figures 364 and 365 exhibit the disadvantages of the deltoid, so far as regards the place of its insertion into the lever; but many muscles Fig. 365. I Action of the Deltoid. A. The scapula. B. The os humeri. C. The deltoid. « have insertions much less favourable than it. The biceps, D, for ex- ample, in Fig. 366,—the muscle which bends the forearm on the arm,— is attached to the forearm ten times nearer the ftlbow-joint or fulcrum than to the extremity of the lever; and if we apply the calculation to it,—supposing the weight of the globe, in the palm of the hand, to be fifty-five pounds and the weight of the limb five pounds,—it would have to act with a force equal to sixty times ten, or six hundred pounds, to raise the weight. Muscles, again, are attached to the bones at unfavourable angles. If they were inserted at right angles in the direction P p, Fig. 364, the whole power would be effectually applied in moving the limb. On the other hand, if the muscle were parallel to the bone, the resistance would be infinite, and no effect could result. In the animal it rarely hap- pens, that the muscle is inserted at the most favourable angle; it is Fig. 366. generally much smaller than a right angle. Reverting to the deltoid, this muscle is inserted into the humerus at an angle of about ten de- grees. Now, a power acting obliquely upon a lever, is to one acting APPLICATION OF MECHANICAL PRINCIPLES. 273 Fig. 367. Insertion of Fibres into Tendon. perpendicularly, as the sine of inclination, represented by the dotted line F s, Fig. 364, to the whole sine P p. In the case of the deltoid, the proportion is as 1,736,482 to 10,000,000. Wherefore, if the muscle had to contract with a force of one hundred and eighty pounds, owing to the disadvantage of its insertion near the fulcrum, it would have, from the two causes combined, to exert a force equal to 1,058 pounds. Again, the direction in which the fibres are inserted into the tendon has great influence on the power developed by the muscle. There are few straight muscles, in which all the fibres have the same direction as the tendon. Fig. 367 exhibits the loss of power, which the fibres must sustain in proportion to the angle of insertion. The fibre t F would, of course, exert its whole force upon the tendon, whilst the fibre t 90°, by its contraction, would merely displace the tendon. Now, the force exerted is, in such case, to the effective force, —that is, to that which acts in moving the limb,—as the whole sine t F is to the sines of the angles at which the fibres join the tendon represented by the dotted lines. Borelli and Sturm have calculated these proportions as follows:—At an angle of 30°, they are as 100 to 87; at 45° as 100 to 70; at 26° as 100 to £9 ; at 14° as 100 to 97 ; and at 8° as 100 to 99. The largest angle, formed by the outer fibres of the deltoid, is esti- mated by Haller at 30° : 'the smallest about 8°. If this disadvantage be taken into account, the deltoid will have to contract with a force equal to 1,284 pounds, to raise fifty-five pounds at the elbow. It is farther contended by Borelli, Sturm, and Haller, that the force of the muscle, as estimated in the preceding calculations, must be doubled, seeing that it has to exert as much force in resisting the bone which affords a fixed point at one extremity, as in elevating the weight at the other. This estimate, if admitted, would elevate the force, to be ex- erted by the deltoid in raising the fifty pounds, to 2,568 pounds. Lastly: Much force is, spent when a muscle passes over many joints ; antagonist muscles must, likewise, exert an influence of the kind, con- suming a certain portion of the force developed in the contraction of the muscle. On the other hand, there are arrangements that augment the power developed by muscles;—as the thick articular extremities of bones; the patella and sesamoid bones in general; all of which enlarge the angle, at which the tendon is inserted into the bone or lever. The projecting processes for muscular attachments, as the trochanters, pro- tuberance of the os calcis, spinous processes of the vertebras, &c, aug- ment the arm of the lever, and are thus inservient to a like valuable purpose. The smoothness of the articular surfaces of bones, tipped, as they are, with cartilage, and the synovia, which lubricates the joints by diminishing friction, as well as the bursas mucosas, which are VOL. II.—18 274 MUSCULAR MOTION. interposed wherever there is much pressure or friction, also aids the power. Trochlese or pulleys act only in directing the force, without augmenting its amount; and the same may be said of the bony canals and tendinous sheaths, by which the tendons of the muscles, especially those passing to the fingers and toes, are kept in their proper course. Still, it must be admitted, that, as regards the effort to be exerted by muscles, it must, in almost all cases, be much greater than the resist- ance to be overcome. The very fact of the lever of the third kind being that which prevails in our movements shows this. The mere mechanician has conceived this to be an unwise construction, and that there is a needless expense of force for the attainment of a determinate end. In all cases we find, that the expense of power has been but little regarded in the construction of the frame; nor is it necessary that it should have been. It must be recollected, that the contraction of the muscle is under the nervous influence, and that, within certain limits, the force, to be employed, is regulated by the influx sent by it to the muscle. The great object in the formation of the body appears to have been—to unite symmetry and convenience with the attainment of great velocity and extent of motion, so that whilst the power is moving through a small space, the weight or resistance shall move rapidly through one more extensive. We have seen that, in these respects, the lever of the third kind is most fitting. With the others less power might be required; but there would be less extent of mo- tion and velocity, whilst the symmetry and convenience of the body would be destroyed. Suppose, for example, that in Fig. 366, the biceps—instead of being inserted at E, near the elbow—had passed on to the wrist,—or, to simplify the matter, to the extremity of the mem- ber ; it would assuredly have acted with more force—the lever having been changed into one of the second kind,—but the hand would have lost that velocity and extent of motion, which are so important to it; and the course of the muscle would have been so modified as to convert the convenient and symmetrical member into a cumbrous, webbed instrument, badly adapted for the multitudinous pur- poses to which it has to be applied. The same effect results, as Sir Charles Bell1 has remark- ed, from the course of ten- dons and their confinement by sheaths, strengthened by ligaments. If the tendon A, Tendon of the Great Toe. Fig. 368, took the shortest course to its termination at B, it would draw up the toe with more force ; but the toe would lose its velocity of movement. 1 Animal Mechanics, Library of Useful Knowledge, p. 27, Lond., 1829. APPLICATION OF MECHANICAL PRINCIPLES. 275 To favour this velocity, we find that the majority of muscles are inserted obliquely into their levers, and Fig. 369. the fibres into the G- _te H_ tendons. By this ar- -A-EE rangement, as we have proved, consi- derable loss of power results; but in the majority of cases, the motion is effect- ed by a less degree of decurtation than if the muscles were straight. Let A B and C D, Figs. 369 and 370, be parts of two ribs that are parallel, and continue parallel till brought into contact by the action of the straight muscle E F; or by that of the oblique muscles F G and F H. Now it is obvious, that when the point Action of Intercostal Muscles. Fig. 370. A liimiHiiiniiiiiiiiiiiiiiiii'iiiiiiiiiiiiiiiiiiiiiiiii C .iiilliilHIH'lllllllillllllllllilllllllllllllllllllllillllllilllillllilillllllllllllllllllllilllllllllllMIIlT) Cr _E SrL Action of Intercostal Muscles. E comes in contact with F, the length of the straight mus- cle E F must be null; whilst that of the oblique muscles will only have ex- perienced a decur- tation equal to G g and H h, Fig. 369 ; and to F g and F h, Fig. 370. It is clear, also, that, in these cases, the straight muscles can never so contract as to admit of a close approximation of the ribs; whilst the oblique muscles will admit of this to a much greater extent. We can, therefore, understand, why the intercostal muscles pass obliquely from one rib to another, as at D and B C, Fig. 371, instead of in a direction perpendicular to the two ribs as at A. There are cases, however, in which a straight muscle may pass between two parallel ribs, and carry them through a given space, with less decurtation of fibres, than any oblique muscle, which has the same origin; but is inserted at a greater distance from the centre of motion, and acts through the medium of a longer lever. Moreover, a mus- cle, with a less degreeof obliquity, may be so situate as to carry the bones through a given space, with a less decurtation of fibres than any other muscle having the same origin but a much greater de- gree of obliquity. Suppose A B and C D, Fig. 372, to be two parallel ribs, of which A B is movable about A as a centre; and sup- Action of Intercostals. 276 MUSCULAR MOTION. P Fig. 372. 1.-T. .A. ||ii|''''''^''iiMiii;i!ii[[iMiiii|,iii'iiiM|iiiii'.iLMi^iiiiliii[i;iiiiiiaiii!!jwiaNiiMiiiiiiiiiiiii;iiiiiiiiiiiil .3i Action of Intercostals. pose it to be brought by the action of the straight muscle E F, and of the oblique muscles E G and E H, into the position A/. The points of insertion of the mus- cles will now be at a, c and e, after having traversed the spaces F a, G c, and H e. If we now, from the point E, as a centre, describe the arcs c b and e d; the spaces d H and b G will indicate the degree of decurtation, which the oblique muscles have experienced, and a F that of the straight mus- cle. This figure also shows, that when the muscles change the relative position of any two bones, they at the same time change the direction of their own action, and vary their lever. When the rib AB is brought into the position A /, the muscles E Gr and E II, by being brought down to c and e, have assumed the positions E c and E e; and have, con- sequently, changed their length, situation, obliquity, and leverage. Again, of the muscles, which are attached to ribs that are parallel, equally movable, and situate at right angles to the spine, those hich pass perpendicularly from one rib to the other will act upon each with equal leverage; and each will approach the other with the same velo- city ; whilst those that pass obliquely from one to the other, will make them approach with different velocities;—a principle which is strikingly applicable to the intercostal muscles. Let us suppose A B and C i), Fig. 373, to be two parallel ribs, articulated with the spine at A and C, and equally movable on these centres of motion. Let D B repre- sent a straight mus- Fig- 373- cle, passing directly from the one rib to /-fy the other; and D B an oblique muscle. The levers of D B, according to the mechanical princi- ples laid down, will be A Band CD, per- pendiculars drawn from the centres of motion to the line of direction of the power. These levers being parallel are of course equal; but the levers of D E will be C F and A G,—also perpendicu- lars drawn from the centres of motion to the line of direction of the power. These levers are of different lengths; and, accordingly, the muscle must act with different degrees of force on the two ribs: so that it will cause C D, on which it acts with the longest lever, to approach A B faster than it makes the latter approach the former,—in the ratio of C F to A G, or with three times the velocity. m i i r 11 n h i n ] i f >; Latin, ululare; German, heulen; Dutch, huilen ; Spanish, aullar ; French, hurler, &c. Hence the word owl. Neighing of the horse.—Latin, hinnire; French, hennir; German, wiehern; Saxon, hncegan, &c. Clocking or clucking of hens.—Latin, glocire; French, glousser; Greek, xa*Ha?eu; German, glucken; Dutch, klokken; Saxon, cloccan, &c. To crow, like a cock.—Greek, xpa£a>; German, krahen ; Dutch, kraayen ; Saxon, craw, &c, whence the word crow, the bird. 1 Glossarium Germanicum, Lips., 1737. 330 MUSCULAR MOTION. The Latin words tinnimentum, tinnitus, tintinnabulum, &c, from tin- nio, "I ring," are all from the radical tin, and imitate the sound ren- dered on striking a metallic vessel. The gurgling of water; the clang- ing of arms; the crash of falling ruins; are of the same character; and the game trictrac, formerly tictac, seems to have been so called from the noise made in putting down the men or dice.1 In whatever manner language was first formed, it is manifest that the different sounds could make but transient impression, until they were reduced to legible characters, which could recall them to mind. On our continent, the fact has often been noticed of a tribe of Indians separating themselves into two parties, and remaining distinct for years. In such case, the language has become so modified, that after the lapse of a considerable period they have scarcely been able to comprehend each other. Hence, the importance of the art of writing,—certainly the most valuable of human inventions. Of this, there have been two kinds, imitative or alphabetical,—and symbolical, all/gorical, or emblema- tical, the latter consisting of hieroglyphics, designs representing ex- ternal objects, or symbolical allegories. The former, or the written representation of spoken sounds, alone concerns us. To attain this; every compound sound has been reduced to certain elementary sounds, which are represented by signs, called letters. These elementary sounds, by combination, form syllables; and the syllables, by combination, words. The number of elementary sounds, admitted in each language, constitutes its alphabet, which differs more or less in certain languages; but as it is entirely a matter of human invention, and as the element- ary sounds, of which the human voice is capable, are alike in the dif- ferent races of mankind, we see readily, that the alphabets of the dif- ferent languages must correspond, although the combinations of letters constituting syllables and words may vary essentially. Into the origin of written legible language, it is not necessary to inquire. We may remark, that the invention has been considered so signally wonderful as to transcend human powers; and hence, St. Cyril, Clement of Alexandria, Eusebius, Isidore, and, in more modern times, Messrs. Bryant, Costard, &c, have been of opinion, that the knowledge of letters was first communicated to Moses by the Almighty himself, and that the decalogue was the earliest specimen of alphabetic writing. Many passages in the writings of Moses show unequivo- cally, however, that written records must have existed prior to his time. In the passage in which writing is first mentioned in the sacred volume, the art is alluded to as one of standing:—"And the Lord said unto Moses, ' Write this for a memorial in a book or table;' " and in a subsequent chapter—" And thou shalt make a plate of pure gold, and grave upon, like the engravings of a signet, Holiness to the Lord."2 The English alphabet is considered to consist of twenty-six letters. It may, however, by ultimate analysis, be reduced to twenty-five sim- ple sounds—A, B, D, E, F, G, H, I, J, K, L, M, N, O, P, R, S, T, U, Y, Z, Ch, Sh, Th, and Ng. To these letters arbitrary names have 1 See De Brasses, Traite de la Formation M'chanique des Langues, &c, i. 232, Par. An. ix. 2 Good, op. citat., ii. 273. VOICE—ARTICULATE LANGUAGE. 331 been assigned, as Bee (B,) See (C,) Dee (D,) &c, which express very different sounds from those that belong to the letter when it forms part of a word or syllable. The word bad is not pronounced bee-a-dee, as the child, just escaped from learning his alphabet, must imagine; hence, he has to unlearn all that he has acquired; or to imagine, that different letters have very different sounds, according to the situation in which they are placed. To obviate this inconvenience, some per- sons are in the habit of teaching their children syllabically from the very first, by which they acquire the true sound attached to each letter of the alphabet.1 In the preceding enumeration of the simple sounds, that constitute the alphabet, C, Q, W, X, and Y, have been excluded, for the following reasons. C has always the sound of either S or K, as in cistern or consonant. Q has the sound of koo, as in quart, (kooarl;) W of oo, as in word (oourd;) X of ks, or Z, as in vex, (vecks,) or Xerxes, {zerkses;) whilst Y has the sound of I or E, as in wry or yard, (n or eeard.) Oh, Sh, -and Th, have been added, as being true alphabetic or simple sounds. Letters have been usually divided into two classes, vowels and conso- nants. The vowels or vocal sounds are so called, because they appear to be simple modifications of the voice formed in the larynx, uninter- rupted by the tongue and lips, and passing entirely through the mouth. Such at least is the case with those that are reckoned pure vowels. These, in the English alphabet, are five in number,—A, E, I, 0, and U. W and Y are, likewise, vowel sounds in all situations. In enunciating A, as in fate, the tongue is drawn backwards and slightly upwards, so as to contract the passage immediately above the larynx. In sounding E, the tongue and lips are in their most natural position without exertion. I is formed by bringing the tongue nearly into contact with the bony palate; O, by the contraction of the mouth being greatest immediately under the uvula, the lips being also some- what contracted. In the production of U, the contraction is prolonged beneath the whole of the soft palate. From these principal vowels, all the other vowel sounds of the language may be formed, by con- sidering them as partaking more or less of the nature of each. They are, in our language, fourteen in number: besides compound sounds, as in oil and pound. Of these fourteen, four belong to A; two to E; two to I; three to 0; and three to U. f Fate. * • Far. A, as in . . . Fast< [ Fall. t-, . (Me. E,asm . . . |Met_ T . ( Pine. I, as in . . . ]pin_ (No. 0, as in . . -j Not ( Move. ( Tune. U, as in . . . \ Tub. ( Bull. 1 Both Lord Stowell and Lord Eldon received the rudiments of their education from Mr. Warden, an approved master of the day, long remembered in Newcastle by the name of Dominie Warden. " His manner of teaching to read had this peculiarity, that instead of sounding each consonant with an auxiliary vowel, as B be, F ef, K ka, and so forth, he confined the expression of each consonant to its own almost mute sound, as B, F or K. This mode of muffling the consonants is said to have been very successful with the learners." The Public and Private Life of Lord Chancellor Eldon, by Horace Twiss, Esq., i. 30, Lond., Ib44. 332 MUSCULAR MOTION. The vowels are more easy of pronunciation than the consonants. They merely require the mouth to be opened; and howsoever it mav be arranged in the enunciation of the different vowels, the vocal tube is simply modified, to vary the impression which has to be made on the organ of hearing. The shape of the cavity is altered; but the passage of the air continues free, and the voice, consequently, issues in an unrestrained manner. Hence, perhaps, the physiological origin of the Danish word Aa, " a river"—a generic term, which became after- wards applied to three rivers in the Low Countries, three in Switzer- land, and five in Westphalia,—the sound of the two broad A's flowing without obstacle, like a river. Time passes away in a similar manner; hence, for a like reason, the Greek aa, which signifies " always, per- petually ;" and the German je, which has the same signification. The consonants are more difficult of enunciation than the vowels; as they require different, and sometimes complex, and delicate move- ments of the vocal tube; and, on this account, they are not acquired so early by children. The term consonant is derived from one of its uses,—that of binding together vowels, and being sounded with them. By most, and according to Mr. Walker,1 by the best grammarians, w and y are consonants when they begin a word; and vowels when they end one. Dr. Lowth,2 however, a man of learning and judgment, who certainly would not suffer in a comparison with any of his opponents, regards them, as the author does, to be always vowels. Physiologi- cally, it is not easy to look upon them in any other light. Yet Mr. Walker exclaims:—"How so accurate a grammarian as Dr. Lowth could pronounce so definitely on the nature of y, and insist on its being always a vowel, can only be accounted for by considering the small attention which is generally paid to this part of grammar." No stronger argument, however, could be used against the useless ex- penditure of time on this subject, than the conclusion to which Mr. Walker himself has arrived; and for which he can find no stronger reasons, than that "if w and y have every property of a vowel, and not one of a consonant; why, when they begin a word, do they not admit of the euphonic article an before them ?" ! The consonants are usually divided into mutes, semi-vowels, and liquids. Mutes are such as emit no sound without a vowel,—b,p, t, d, k, and c and g hard. Semi-vowels are such as emit a sound, without the concurrence of a vowel, as/, v, s, z, x, g soft or j. IJquids are such as flow into, or unite easily with, mutes, as I, m, n, r. These letters issue without much obstacle; hence perhaps their name. In tracing the modes in which the different consonants are articulated, we find that certain of them are produced by an analogous action of the vocal tube; so that the physiology of one will suffice for the other. For instance, the following nearly correspond:— p f t s k ch & & & & & & b v d z g j B and P are produced when the lips, previously closed, are suddenly opened. B differs from P in the absence, in the latter, of an accom- 1 Preface to his Dictionary. 2 Introduction to English Grammar, p. 3. VOICE—ARTICULATE LANGUAGE. 333 panying vocal sound. F and Y are formed by pressing the upper incisor teeth upon the lower lip. They are, consequently, not well enunciated by the aged, who have lost their teeth. F differs from Y only in the absence of an accompanying vocal sound. T and D are formed by pressing the tip of the tongue against the gums behind the upper incisor teeth. D is accompanied by a vocal sound; T not. S and Z are produced by bringing the point of the tongue nearly in con- tact with the upper teeth, and forcing the air against the edges of the teeth with violence. S differs from Z in the absence of the vocal sound. K and G are formed by pressing the middle of the tongue against the roof of the mouth, near the throat; separating the parts a little more rapidly to form the former, and more gently to form the latter of those letters. In K, the accompanying vocal sound is absent. Ch and J are formed by pressing t to sh; and d to zh. In Ch, there is no ac- companying vocal sound. SH and ZH are formed in the same part of the tube as s and z. TH is formed by protruding the tongue between the incisor teeth, and pressing it against the upper incisors to produce its sound in think. Its sound in that is effected by pressing the tongue behind the upper incisor teeth. In the former case, it is unaccompanied by a vocal sound. In M, the lips are closed, as in B and P.; and the voice issues by the nose. N is formed by resting the tongue against the gums, as in the enunciation of t and d; breathing through the nose with the mouth open. In L, the tip of the tongue is pressed against the palate, the sound escaping laterally. In forming the letter K, the middle and point of the tongue strike the palate with a vibratory mo- tion; the tip being drawn back. Lastly, in the formation of H, the breath is forced through the mouth, which is everywhere a little con- tracted. It need hardly be said, that the enunciation of these letters requires, that the vocal tube, or the parts concerned in the function, shall be in a sound condition.1 A-few years ago (1846), an ingenious German, named Faber, exhi- bited publicly in Philadelphia a speaking automaton,"4which he subse- quently, in England, called "Euphonia or Speaking Automaton,"2 in the construction of which he found that the alphabet can be simplified still further. The precise mechanism he did not unfold; but affirmed that the parts were made of elastic materials to resemble as nearly as possible the human vocal organs. These parts were susceptible of varied movements by means of keys. The author was much struck by the distinctness with which the automaton could enunciate various letters and words. The combination three was well pronounced; the th less perfectly; but astonishingly well. It also enunciated diphthongs and numerous difficult combinations of sounds. Sixteen keys were sufficient to produce all the sounds. It sang "God Save the Queen" and "Hail Columbia"—the words and air combined. The following is the alphabet of the automaton. 1. Five simple vowels: for example—a as in father; o as in home; u as in ruin; i as e, and e as a. 2. Nine consonants, I, r, w (the German w—the English w is oo), 1 Mayo, Outlines of Human Physiology, 3d edit., p. 357, Lond., 1833 ; also, Haller, Element. Physiol., lib. ix. §4, Lausann., 176C. 2 J. Bishop, On Articulate Sounds and on the Causes and Cure of Impediments of Speech, p. 24, London, 1851. 334 MUSCULAR MOTION. /, s, sh in shall, and b, d, g hard, as in give. 3. A nasal sound and an aspirate; making in all sixteen simple sounds. From these the com- pound sounds are formed, as in the following examples: b and the nasal form m; d and the nasal, n: if the nasal sound be prevented, me be- comes be; not becomes dot; g and the nasal form ng; b and the aspirate form p; d and the aspirate, t; g and the aspirate, k; sh and the nasal, th; wf ox uffoxvo. v; d and sh,j and g soft; t and sh, ch in chin. The diph- thongs admitted by Mr. Faber are ai i, eu u, and au sounded as in how. Wolfgang von Kempelen,1 in a work on the mechanism of human speech, which is considered classical in Germany,—and in which he treats of a speaking automaton (Sprachmaschine) of his invention,— divides the consonants into four classes. 1. Mutes (ganz stumrae), as K, P, T. 2. Explosives (Win d m i 11 au t e r), as F, H, Ch, S, and Sh. 3. Vocal consonants (Stimmitlauter), as B, D, G, L, M, and N; and 4. Vocal explosives (Wind und Stimmlauter zugleich), as R, I, W, Y, Z. Dr. Thomas Young has, likewise, divided the English conso- nants into classes; of which he enumerates five. 1. Pure semi-vowels, as L, R, Y, Z, and J. 2. Nasal semi-vowels, as M and N. 3. Explosive letters, as B, D, and G. 4. Susurrant letters, as H, F, X, and S; and 5. Mutes, as P, T, K; but the most satisfactory classification, in a physio- logical, as well as philological point of view, is according to the parts of the vocal tube more immediately concerned in their articulation. Labial. Dento-labial. Linguo-dental. Linguo-palatal. Guttural. B M P F V Th D JL N RSTZ Ch Sh Ng G K That this physiological arrangement has had much to do with the formation of congenerous tongues more especially is exhibited by facts connected with the permutation or change of letters;—when a word passes, for example, from one of the Teutonic or Romanic lan- guages to another. " The changes of vowels," says Mr. Lhuyd,1 " whether by chance or affectation, are so very easy and so common in all languages, that in etymological observations, they need not, indeed, be much regarded; the consonants being the sinews of words, and their alterations therefore the most perceptible. The changes of consonanta also into others of the same class, (especially labials, palatab, and Un- guals,) are such obvious mistakes, that there is no nation where the common people in one part or other of their country do not fall into some of them." A few examples will show to what extent this permu- tation occurs between letters of the same class in different languages. In this view, we may regard the labials and dento-labials as belonging to the same. P into B.—Greek,Xf4-; Latin,phlebs. Latin, (and Greek,) episcopus; English, bishop; An<;lo-Saxon, biscop ; German, b i s ch o f. P into F and V.—Latin, pater; German, v a t e r; Dutch, vader ; English, father. 1 Mechanismus der menschlichen Sprache, S. 228, Wien, 1791; and Rudolphi, Grund- liss der Physiologie, 2ter Band, lste Abtheil., S. 3US, Berlin, 1823. 2 Archaeologia Britunnica, Oxford, 1707. VOICE—ARTICULATE LANGUAGE. 335 T into S.—German, b e s s e r; English, better. German, wasser; English, water. D into Th.—German, das: Dutch, dat; English, that. T into Z.—German, z u n g ; Dutch, tong ; English, tongue. German, z w e i g; Eng- lish, twig. L into R.—Spanish, Gil Bias; Portuguese, Gil Bras. Latin, arbor; Spanish, albero. C or K into G.—Latin hemicranium; French, migraine. Latin, cibarium; French, gibier. Latin, acer; Italian, a^rro. Latin, alacer; Italian, allegro. Greek, xwtvoc; Latin, cygnus. The most harmonious languages are such as have but few consonants in their words, compared with the number of vowels; hence the musical superiority of the Greek and Italian, over the English, German, &c. "Among certain northern nations," says M. Richerand,1 "all articu- lated sounds appear to issue from the nose or the throat, and make a disagreeable pronunciation, doubtless because it requires greater effort; and he who listens, sympathizes in the difficulty, which seems to be felt by him that speaks;"—and he adds :—" would it not seem that the inhabitants of cold countries have been led to use consonants rather than vowels, because as the pronunciation does not require the same opening of the mouth, it does not afford the same space for the contin- ual admission of cold air into the lungs ?" ! The whole of Richerand's remarks on this topic are singularly fantastic and feeble, and unwor- thy of serious discussion. In regard to consonants, it has been presumed, that some common imitative principle must have existed with all nations, so as to cause them to conform in adopting such as produce a certain sound to convey the same effect to the ear. Dr. John Wallis2 turned his attention to this matter, chiefly as regards the English language, and he has col- lected a multitude of examples to show, that a certain collocation of consonants at the commencement of a word generally designates the cl|ss of ideas intended to be conveyed by it. For instance, he re- marks that:— Str, always carries with it the idea of great force and effort—as strong, strike, stripe, strife, struggle, stretch, strain, &c. 67, the idea of strength, but in less degree—the vis inertia;, as it were:—as stand, stay, stop, stick, stutter, stammer, stumble, stalk, steady, still, stone, &c. Thr, the idea of violent motion :—as throw, thrust, throb, threat, throng, &c. Wr, the idea of obliquity or distortion:—as wry, wreathe, wrest, wring, wrestle, wrench, wriggle, wrangle, &c. Br, the idea of violent—chiefly sonorous—fracture or rupture :—as break, brittle, brust, or burst, brunt, bruise, broil, &c. Cr, the idea of straining or dislocation, chiefly sonorous :—as crack, creak, crackle, cry, crow, crisp, crash. Other words, beginning with these consonants, communicate the idea of curvature, as if from curvus :—as crook, cringe, crouch, creep, crawl, cripple, crumple, crotchet, &c. Others, again, denote decussation, as if from crux:—as cross, cruise, crutch, crosier. Shr, the idea of forcible contraction :—as shrink, shrivel, shrug, shrill, &c. Gr, the idea of the rough, hard, onerous and disagreeable, (either owing to the letter of roughness r, or from gravis,)—as grate, grind, gripe, grapple, grieve, grunt, grave, &c. Sw, the idea of silent agitation or of gentle lateral motion:—as sway, swag, swerve, sweat, swim, swing, swift, &c. Sm, a very similar idea to the last:—as smooth, small, smile, smirk, &c. CI, the idea of some adhesion or tenacity:—as cleave, clay, cling, climb, cloy, cluster, close, &c. Sp, the idea of some dispersion or expansion, generally quick, (especially with th« addition of the letter r,) as spread, spring, sprig, sprinkle, split, splinter, spill, &c. 1 Elemens de Physiologie, edit, cit., p. 298. * Uraimnatica Linguae Anglicame, &c, edit. 6, Loud., 1765. 336 MUSCULAR MOTION. SI, the idea of a gently gliding or slightly perceptible motion:—as slide, slip, slip- pery, slime, sly, slow, sling, &c. Lastly: Sq, Sk, Scr, denote violent compression:—as squeeze, squirt, squeak, squeal, skreek, screw, &c. Other interesting observations on the collocation of consonants, at the termination, and in the body, of words, are contained in the gram- mar of Wallis. His remarks, however, are chiefly confined to his own tongue. The President de Brosses1 has taken a wider range, with a similar object, and endeavoured to discover why certain consonants, or a certain arrangement of consonants in a word, should designate certain properties in all languages. Why, for instance, the st should enter into most words signifying firmness and stability:—as, in the Sanskrit, stabatu, to stand, stania, a town, &c; in the Greek, or^, a column, erftpfoj, solid, immovable, attipa, sterile, remaining constantly without fruit, orjjpifw, "I fix firmly," &c; in the Latin, stare, to stand; stirps, a stem; stupere, to be astonished; stagnum, stagnant water, &c; and he might have added, in the German, still-stehend, stagnant; stadt, a town; stand, condition; sterben,to die; still-stand, cessation, &c, besides the English words, commencing with st, already quoted from Wallis. He farther inquires, why words, commencing with sc, denote hollowness, as uxortru, I dig; oxo^*?, skiff or boat, in the Greek; scutum, a shield; scyphus, a large jug; sculpere, to engrave; scrobs, a ditch, in the Latin;—ecuelle, formerly escuelle, a dish; scarifier, to scarify; scabreux, scabrous; sculpture, &c, in the French; and many similar words might be added from our own language. Ecrire, formerly escrire, the French for " to write" is from the Latin scribere: and, an- ciently, a kind of style was used for tracing the letters in wax; which instrument, by a like analogy, was called by the Greeks, a.ot, a flame; ykt), a vein; $\eytdcov, a burning river in the infernal regions:—in the Latin, flamma, flame; fluo, I flow; flatus, wind; fiuctus, wave, &c.;—in the German, flossen, to float; floten, to play on the flute; fluss, a river; f 1 ug, flight, &c; and in the French and English words of the same meaning. Lastly, the idea of roughness and asperity is conveyed by the letter r, as in the words rough, rude, rock, romp, &c. How different, for example, in smoothness are the two following lines, in which the S ,' Traite de la Formation M'chanique des Langues et des Principes Physiques de l'Etymologie, i. 238, Paris, An ix. 2 Op. cit., i. 261. VOICE—ARTICULATE LANGUAGE. 337 predominates, from those that succeed them, where the R frequently, and perhaps designedly, occurs: " Softly sweet in Lydian measures, Soon he soothed his soul to pleasures ;" And:— " Now strike the golden lyre again, A louder yet, and yet a louder strain ; Break his bands of sleep asunder; And rouse him like a rattling peal of thunder." Dkyden's "Alexander's Feast." The foregoing remarks, suggested by those of Wallis and M. de Bros- ses, must not, however, be received too absolutely. In the condition in which we find languages at the present day, it would be impossible that they should hold good universally; but they will tend to show, that the physiology of the voice is intimately connected with this part of philo- logy ; and that the sounds emitted by the agency of particular parts of the vocal tube, may have led to the first employment of those sounds, according to the precise idea it may have been desired to convey;— gutturals, for example, for sounds conveying the notion of hollowness; —resisting dentals, that of obstacles, &c. The words mamma and papa are composed of a vowel and consonant, which are the easiest of enun- ciation; and which the child, consequently, pronounces and unites earlier than any other. Hence they have become the infantile appella- tions for mother and father with many nations. President de Brosses1 affirms—and he has brought forward numerous examples to prove his position—that in all ages, and in every country, a labial, or, in default of it, a dental, or both together, are used to express the first infantile words "papa" and •'mamma;" but it is scarcely necessary to say, that the child, when it first pronounces the combinations, attaches no such meaning to them as the parent fondly imagines. There is a rhetorical variety of onomatopoeia, frequently considered under the head of alliteration, but by no means deriving its chief beau- ties from that source. It happens when a repetition of the same letter concurs with the sonorous imitations already described; as in the fol- lowing line in one of the books of the iEneid of Yirgil;— " Lucfantes venfos tempestatesque sonoras," in which the frequent occurrence of the letter of firmness and stability, T, communicates the idea of the striking of the wind on objects. In the " Andromaque" of Racine, a line of this character occurs: "Pour qui sont ces serpens qui sifflent sur vos tetes,"2 in which the sound impressed on the ear has some similarity to the hissing of serpents; and in the "Polme des Jardins" of the Abbe De- lille, there is the following example:— " Soit que sur le Zimon une riviere Zente, Derou/e en paix les p/is de son onde indotente; Soit qu'a travers les rocs un torrent en courroux Se brise avec fracas."J 1 Op. cit., i. 244. 2 " For whom are those serpents that hiss o'er your heads ?" 8 Which may be translated as follows:— " If o'er deep slime a river laves In peace the folds of its sluggish waves ; Or o'er the rocks a torrent breaks In wrath obstrep'rous." vol. ii.—22 338 MUSCULAR MOTION. In the first two lines, the Liquid L denotes the tranquil flow of the river; whilst in the two last, the letter of roughness and asperity, R, resembles the rushing of the stream like a torrent. The remarks already made will have exhibited the radical difference in the ideas communicated by the sound of those letters, by the common consent of languages. In the German this variety of expression is often had recourse to; and by none more frequently than by the poet Biirger.1 The English language affords a few specimens, but not as many as might be imagined. Of simple alliteration there are many; some that give delight; others that do violence to the suggestive principle; but there are comparatively few where the words are selected, which by their sound convey to the mind the idea to be communicated. The galloping of horses may be assimilated by a frequent succession of short syllables; slow, laborious progression by the choice of long; but in the onomatopoeia in question, the words themselves must consist of such a collocation of one consonant, or of particular consonants, as adds force to the idea communicated by the words collectively. Of this, we have a good example in the lines before cited, in which the repetition of the letter R, in the phonetic words, adds considerable force to the idea intended to be conveyed by the passage— " Break his bands of sleep asunder; And rouse him like a rattling peal of thunder," and in Byron's " Darkness," " Forests were set on fire—but hour by hour They fell and faded—and the crackling trunks Extinguish'd with a crash—and all was black."2 /. Singing. The singing voice differs from other vocal sounds in consisting of appreciable tones, the intervals of which can be distinguished by the ear, and admit of unison. Under the sense of hearing we endeavoured to show, that the musical ear is an intellectual faculty; and that the ear is only the instrument for attaining a knowledge of sounds, which are subsequently reproduced by the larynx, under the guidance of the intellect. In this respect, therefore, there is a striking resemblance between music and spoken language. Like the latter, singing admits of considerable difference, as regards intensity, timbre, &c. Yoices are sometimes divided into the grave and acute; the difference between them amounting to about an octave. The former is the voice of the adult male; but he is capable of acute sounds, by assuming the falsetto, which M. Savart3 conceives to be pro- duced in the ventricles of the larynx; M. Bennati in the pharynx; and more recently, Mr. J. Bishop4 has suggested, that it may arise 1 Art. Alliteration, and Onomatopoeia, in Encyclop^die, par Diderot, D'Alembert, &c, and in Allgemeine Deutsche Real-Encyclopadie fur die gebildeten Stande, (Conversa- tions Lexikon), Aufl. 8, Leipz., 1837. 2 See, on Onomatopoeia, by the author, Virginia Literary Museum, p. 65, Charlottes- ville, 1840. 3 Magendie's Journal de Physiologie, torn, v., Paris, 1825. 4 Proceedings of the Royal Society, No. 65, London, 1847. See, also, his Art. Voice, Cyclop, of Anat. and Physiol., iv. 1483, Lond., 1S52. VOICE—SINGING. 339 either from the partial closing of the glottis, or from a nodal division* of the vocal cords, " the pitch of the sound in the production of this peculiar modification of the voice being such, that the column of air in the vocal tube is of the precise length requisite to vibrate in unison with the larynx." The mode, however, in which the falsetto voice is produced is by no means determined. It has given rise to great di- versity of views.1 The acute voice is that of the grown female, chil- dren, and eunuchs. According to M. Pouillet,2 the gravest sound of the male voice makes 190 vibrations per second; the most acute 678 per second; whilst the female voice makes 572 vibrations for the gravest, and 1606 for the most acute. By adding all the tones of an acute to those of a grave voice, they are found to embrace nearly three octaves; but, according to M. Magendie, it does not appear, that such a compass of voice, in pure and agreeable tones, has ever existed in one individual.3 On the other hand, M. Biot calculated three octaves and a half to be the extreme range: this, Mr. Bishop4 says, he knows from experience is too low an estimate. Independently of the falsetto, the compass of the natural voice would seem to rarely exceed two octaves; but in some cases, as in those of Catalani and Malibran, it has extended beyond three. Some singers can descend sixteen tones below, others can rise sixteen above, the medium. The former are called tenor bass; the latter soprano; but hitherto no example has oc- curred of a person, who could run through the thirty notes. v The musician establishes certain distinctions in the voice; such as counter, tenor, treble, bass, &c. We find it, also, differing considerably in strength, sweetness, flexibility, &c.s The singing voice, according to M. Bennati,6 is not limited to the larynx,—the pharynx being likewise concerned. The voice, produced in those two different parts, has long been termed voce dipetto, and voce di testa. M. Bennati calls the former laryngeal notes or notes of the first register; the latter supra-laryngeal or notes of the second register; and M. Lepelletier designates them laryngeal and pharyngeal respectively;— comprising, in the dependencies of the pharynx, the tongue, tonsils, and velum palati, by means of which the latter class of sounds is elicited. The laryngeal voice, which is always more elevated by an octave in the female than in the male, is most commonly met with. It furnishes the types called, 1. Soprano; 2. Alto or Contralto; 3. Tenor; •i. Bass. The first two of these belong to the female voice; the last two to the male. They are classed according to their pitch or the middle note of their primary register, as in the subjoined table :— 1 Muller's Physiology, P. iv. p. 1032, Lond., 1838. 2 Ehniens de Physiologie Exporimentale, torn. iii. 130, Paris, 1832. 3 Precis Elementaire, i. 262. 4 The Lond. and Edinburgh Philosophical Magazine, for October, 1836, p. 272. 6 Magendie's Journ. de Physiologie, x. 179. 6 Recherches sur le M canisme de la Voix Humaine, Paris, 1832. 340 MUSCULAR MOTION. it— ---------------------------- ------ &— 90* L- « BASSO. BARITONE. ^--***----w**---------j------------ TENOR. ALTO. '•*----»*»---- --- ®: MEZZO-SOPRANO. SOPRANO. The characteristic of these voices, however, is derived less from their pitch than from their timbre or quality. The bass voice gene- rally descends lower than the tenor, and its strength lies in the low notes. The contralto is distinguished for its power in the lower notes of the female voice. Some bass singers can, however, ascend high; and the contralto occasionally ascends as high as the soprano. The baritone is intermediate between the bass and the tenor; the mezzo- soprano intermediate between the alto and soprano. The pharyngeal voice presents only modifications of the above types. It is met with in but few persons in its finest developement. It has usually been supposed to be formed by the superior ligaments of the larynx, or in the ventricles; but these gentlemen esteem it demon- strated, that it is formed at the guttural aperture, circumscribed by the base of the tongue, velum palati, its pillars, and the tonsils. By it is produced the baritenor, the contraltino tenor, and the soprano sfogalo. Bennati concludes his memoir on the human voice by remarking,— that not only are the muscles of the larynx inservient to the modula- tion of the notes of song, but those of the os hyoides, tongue, and the superior, anterior, and posterior part of the vocal tube are called into action, without the simultaneous and properly associated operation of which the degree of modulation requisite for song could not take place. When the voice is raised in the scale from grave to acute, a corre- sponding elevation takes place in the larynx towards the base of the GESTURES. 341 cranium. By placing the finger on the pomum Adami, this motion can be easily felt; at the same time, the thyroid cartilage is drawn up within the os hyoides, and presses on the epiglottis; the small space between the thyroid and cricoid closes; the pharynx is1 contracted; the velum pendulum depressed and carried forwards; the tonsils approach each other; and the uvula is folded on itself. The reverse of these phenomena takes place during the descent of the voice.1 It has been already remarked, that the natural voice or cry is con- nected with the organization of the larynx. So far as it can be modi- fied into tones independently of the participation of the intellect, a natural singing voice may be said to exist. To repeat, however, any song, requires both ear and intelligence; and, therefore, singing may be said to have originated in social life. It can be employed, as it is in many of our operas, to depict the different intellectual and moral conditions, "And bid alternate passions fall and rise." When the air is accompanied by the words, or is articulated, we are capable of expressing, by singing, any of the thoughts or feelings, that can be communicated by ordinary artificial language. Declamation is a kind of singing, except that the intervals between the tones are not entirely harmonic, and the tones themselves not wholly appreciable. With the ancients—it has been imagined—it differed much less from singing than with the moderns, and probably resembled the recitative of the operas. The ingenious work of Dr. James Rush of Philadelphia,2 may be consulted on all this subject, with great advantage. b. Gestures. Under this appellation, and that of muteosis, are included those functions of expression, that are addressed to the sight and touch. It comprises not only the partial movements of the face, but also those of the upper extremities; besides the innumerable outward signs that characterize the various emotions. In many tribes of animals, the conventional language appears to be almost, if not entirely, confined to the gestures; and even in man—favoured beyond all animals in the facility of communicating his sentiments by the voice—the language of gestures is rich and comprehensive. It is in the gestures of the face chiefly, that he far exceeds other animals. This is, indeed, in him, the great group of organs of expression. In animals, the func- tion is distributed over different parts of the body, the face assuming but little expression, whilst the animal is labouring under any emo- tion, if we make exception of the brute passion of anger and of one or two others. Hence it is, that, by some naturalists, man has been de- fined, by way of distinction, " a laughing and crying animal." In animals, almost all the facial expression of internal feeling is confined to the eye and mouth, but, in addition, the attitude of the body is 1 Bishop and Bennati, in op. cit.; and Bushnan, in Orr's Circle of the Sciences, vol. i. p. 132, London, 1854; or the American reprint of his Contribution under the title of The Principles of Animal and Vegetable Physiology, &c, p. 190, Philad., 1854. ' Philosophy of the Human Voice, 3d edit., Philad., 1845. 342 MUSCULAR MOTION. Fig. 391. variously modified, and the hair is raised by the panniculus carnosus, as we see on the back of the dog when enraged. In the human countenance, alone, in the state of society, can the passions be read,—the rest of the body being covered by clothing; and even were it not, the absence of a coat of hair, and of a panniculus carnosus, would enable it to minister but little to expression. The skin of the face is very fine, and on certain parts, as the lips and cheeks, is habitually more or less florid, and admits of considerable and expressive variations in its degree of colour. The union of the different parts composing the face gives occa- sion' to numerous reliefs, which are called traits or features; and beneath the skin are muscles, capable, by their contraction, of modifying the features in a thousand ways. To comprehend fully the physiology of the facial expression of the pas- sions, a few observations on the mus- cles of the human face will be neces- sary. (Fig. 391.) The eyebrow is greatly concerned in expression; and certain muscles are attached to it for the purpose of moving it. The fasciculus of fibres which de- scends from the frontal muscle, and is attached to the side of the nose, has been esteemed, by some, a separate muscle, and to have a distinct opera- tion. It draws the inner extremity of the eyebrow downwards. When the orbicularis palpebrarum, and the last muscle act, there is a heavy lowering expression. If they yield to the action of the frontal muscle, the eyebrow is arched, and there is a cheerful, inquir- ing expression. If the corrugator su- hyoid muscle pierced by posterior belly of percilti acts, there is more Or leSS of digastricus. 24. Mylo-hyoideus muscle. 25. ■*■ . ' . . _ . „ . upper part of sterno-mastoid. 26. Upper mental anguish, or of pamtul exercise of thought. If it combines with the frontalis, the forehead is furrowed, and there is an upward inflection of the inner extremity of the eyebrow, which indicates more of querulous and weak anxiety. " The arched and polished forehead," says Sir Charles Bell—of whose elegant and accurate Essays1 the author will occasionally avail himself on this branch of the subject—" terminated by the distinct line of the eyebrow, is a table, on which we may see written, in perishable characters, but distinct while they continue, the prevailing cast of thought; and by Muscles of the Head and Face. 1. Frontal portion of occipito-frontalis. 2. Occipital portion. 3. Aponeurosis. 4. Or- bicularis palpebrarum, which conceals cor- rugator supercilii and tensor tarsi. 5. Py- ramidalis nasi. 6. Compressor nasi. 7. Or- bicularis oris. 8. Levator labii superioris alseque nasi. The figure is placed on nasal portion. 9. Levator labii superioris pro- prius ; the lower part of the levator anguli oris is seen between muscles 10 and 11. 10. Zygomaticus minor 11. Zygomaticus major. 12. Depressor labii inferioris. 13. Depressor anguli oris. 14. Levator labii inferioris. 1.5. Superficial portion of masseter. 16. Its deep portion. 17. Attrahens aurem. 18. Buc- cinator. 19. Attolens aurem. 20. Temporal fascia which covers temporal muscle. 21. Retrahens aurem. 22. Anterior belly of di- gastricus muscle; the tendon seen passing through its aponeurotic pulley. 23. Stylo "e pi 24. of sterno-mastoid. part of trapezius. The muscle between 25 and 26 is the splenius 1 Essays on the Anatomy and Philosophy of Expression, 3d edit., Lond., 1844. GESTURES—MUSCLES OF THE FACE. 343 the indications here, often the mere animal activity, displayed in the motions of the lower part of the face, has a meaning and a force given to it. Independently of the actions of the muscles, their mere fleshi- ness gives character to this part of the face. The brow of Hercules wants the elevation and form of intelligence; but there may be ob- served a fleshy fulness on the forehead, and around the eyes, which conveys an idea of dull brutal strength, with a lowering and gloomy expression, which accords with the description in the Iliad." Sir Charles separates the orbicularis palpebrarum into two muscles;— the outer, fleshy, circular band, which runs round the margin of the orbit; and the lesser band of pale fibres, which lies upon the eyelids. The latter is employed in the act of closing the eyelids, but the former is only drawn into action in combination with the other muscles of the face in expressing passion, or in some convulsive excitement of the organ. In laughing and crying, the outer and more powerful muscle is in action, gathering up the skin about the eye, and forcing back the eyebiHl itself. In drunkenness, the power of volition over this muscle is diminished; and there is an attempt to raise the upper eyelid by a forcible elevation of the eyebrow. The muscles of the nostrils are; 1st, levator labii superioris alozque nasi, which, as its name imports, raises the upper lip and nostril; 2dly, compressor nasi, a set of fibres which compress the nostril; and 3dly, depressor alee nasi, which lies under orbicularis oris, and whose function is indicated by its name. The three muscles serve to expand and con- tract the opening or canal of the nostril, moving in consent with the muscles of respiration, and thus the inflation of the nostrils indicates general excitement, and animal activity. The muscles of the lips are; 1st, levator labii proprius, which raises the upper lip; 2dly, levator anguli oris, which raises the angle of the mouth; and 3dly, the zygomatic muscle, which is inserted into the angle of the mouth. Sometimes an additional muscle of the name exists:— zygomaticus minor. These last muscles raise the upper lip and angle of the mouth, so as to expose the canine teeth. If they be in action contrary to the orbicularis oris, there is a painful and bitter expression ; but if they be influenced along with the orbicularis oris, and orbicularis palpebrarum,—if the former of these muscles be relaxed, and the latter contracted,—there is a fulness of the upper part of the face, and a cheerful, smiling expression of countenance. The orbicularis oris closes the mouth; and, when allowed to act fully, purses the lips. The nasalis labii superioris draws down the septum of the nose. The triangularis oris or depressor labiorum indicates, by its name, its function. The quadratus menti is a depressor of the lower lip. The levatores menti, by their action, draw up the chin, and project the lower lip ; and the buccinator is chiefly for turning the alimentary bolus in the mouth; and, in broad laughter, retracts the lips. The orbicularis muscle is affected in the various emotions of the mind; trembling and relaxing in both I grief and joy; it relaxes pleasantly in smiling. The union of these various muscles at the angle of the mouth pro- duces the fleshy prominence noticed in those who have thin faces; and who are, at the same time, muscular. When the cheeks are fat and full, the action of these muscles produces the dimpled cheek. The 344 MUSCULAR MOTION. angle of the mouth is full of expression, according as the orbicularis, or the superior or inferior muscles inserted into it have the preponder- ance. Lastly; the temporal is a strong muscle, which raises the lower jaw. It is assisted by the masseter, a deep-seated muscle, which lies on the outside of the lower jaw; arises from the jugum, and is inserted into the angle of the jaw. Two different nerves are distributed to these muscles,—the fifth pair, and portio dura or facial of the seventh; the latter of which, according to the experiments of Sir 392. Charles Bell, is concerned in the instinctive movements of expression; and comparative anatomy exhibits, that the number and intricacy of these nerves vary in proportion to the animal's power of Expres- sion. The nerves of the face and neck of the monkey are numerous, and have frequent connexions; but on cutting the seventh pair or respiratory nerve of the face of Sir Charles Bell's system, the features are found to be no longer in- fluenced by the passions. Yet the skin continues sen- sible, and the muscles of the jaws and tongue are capable of the actions of chewing and swallowing. If the respira- tory nerve of one side be cut, the expression of that side is destroyed; whilst the chattering, grinning, and other movements of expres- sion continue on the other. In a dog, too, if the respira- tory nerve of the face be cut, he will fight as bitterly, but with no retraction of his lips, sparkling of the eye, or draw- ing back of the ears. The face is inanimate, although the muscles of the face and jaws, so far as they are liable to be influenced through other nerves, continue their office. The game-cock, in the position of fighting, spreads a ruff of feathers around his head. The position of his head and the raised feathers are the expressions of hostile excitement; but on the division of the respiratory nerve, the feathers are no longer raised, although the pugnacious disposition continues. It has been found, moreover, that if the galvanic influence be passed from one divided extremity of the Distribution of Facial Nerve. 1. Facial nerve, escaping from stylo-mastoid foramen, and crossing ramus of lower jaw; the parotid gland has been removed in order to see the nerve more distinctly. 2. Pos- terior auricular branch ; the digastric and stylo-mastoid filaments are seen near origin of this branch. 3. Temporal branches, communicating with (4) branches of frontal nerve. 5. Facial branches communicating with (6) infra-orbital nerve. 7. Facial branches, communicating with (8) mental nerve. 9. Cervico-facial branches communicating with (10) superficialis colli nerve, and forming a plexus (11) over sub- maxillary gland. Distribution of branches of the facial in a radiated direction over side of face constitutes the pes anse- rinus. 12. Auricularis magnus nerve, one of ascending branches of cervical plexus. 13. Occipitalis minor, ascend- ing along posterior border of sterno-mastoid muscle. 14. Superficial and deep descending branches of cervical plexus. 15. Spinal accessory nerve, giving off a branch to external Burface of trapezius muscle. 16. Occipitalis major nerve, posterior branch of second cervical nerve. GESTURES—NERVES OF THE FACE. 345 Fig. 393. respiratory nerve to the other, the facial expression returns; and, in certain cases of incomplete hemiplegia, in which the movements of ex- pression of the face were alone rendered impracticable, the disease was found to have implicated only the respiratory or facial nerve. The views of Sir Charles Bell regarding the connexion alleged by him to subsist between the seventh pair and the associated movements of re- spiration have, however, been contradicted by the experiments of Mr. Mayo,1 and his inferences regarding the fifth pair as being jointly a nerve of sensation and of voluntary motion have been considered to require qualification. By dividing the portio dura of the seventh pair in the ass, and on both sides instead of one, as done by Sir Charles Bell, Mr. Mayo found, that the nerve presides over simple voluntary motion only; and by a similar division of the se- cond and third branches of the fifth, at their points of convergence, he showed, that the lips were deprived of sensa- tion, not of motion. "No doubt, I believe," says Mr. Mayo, " is now en- tertained, that the infer- ence which I drew from these experiments is correct; namely, that the portio dura of the seventh pair is a simple voluntary nerve, and that the facial branches of the fifth are exclu- sively sentient nerves." In the prosecution of his inquiries, Mr. Mayo ob- served, that the masseter muscle, temporal, ptery- goids, and circumflexus palati receive no branch- es from any nerve ex- cept the fifth, and yet that they receive no twigs from the ganglionic portion of the nerve; and thence he concludes, that almost all the branches of the large or ganglionic portion of the fifth pair are nerves of sensation, whilst those of the small fasciculus or ganglionless portion are nerves of motion. This smaller portion of the fifth pair issues from the peduncles of the brain; constitutes a gangliform plexus with the inferior maxillary only; presents the common aspect of most nerves of the body, and is distri- Plan of the Branches of the Fifth Nerve, modified from a sketch by Sir C. Bell. a. Submaxillary gland, with the submaxillary ganglion above it. 1. Small root of the fifth nerve, which joins the lower maxillary division. 2. Larger root, with the Gasserian ganglion. 3. Ophthal- mic nerve. 4. Upper maxillary nerve. 5. Lower maxillary nerve. 6. Chorda tympani. 7. Facial nerve. 1 Outlines of Human Physiology, 4th edit., p. 254, London, 1837. 346 MUSCULAR MOTION. buted to the chief muscles concerned in the process of mastication. Hence it was termed by Bellingeri1 nervus masticatorius ; and by Sir Charles Bell, long afterwards, motor or manducatory portion of the fifth pair. To this smaller fasciculus of the fifth, twigs from the ganglionic portion of the nerve are distributed. The ganglionless portion, and portio dura of the seventh, Mr. Mayo conceives to be voluntary nerves to parts, which receive sentient nerves from the larger or ganglionic portion of the fifth. The facial nerve, however, after it has passed through the parotid gland, becomes sensory also, owing to its havino- received a twig from the fifth pair. Pathology affords numerous examples of injury done to the facial nerve. In some of these, the nerve itself may be in a morbid condi- tion in a portion of its Fig- 394. course; in others, the part of the encephalon, whence the nerve originates, may be the seat of the lesion. The prognosis will, of course, vary according to the seat; but, as a general rule, paralysis of the facial nerve is not of great mo- ment. The author has seen several cases of partial paralysis of this kind; some of which have wholly disappeared; but in others the loss of power appears to be permanent. In a case, which presented itself to him in the Baltimore Infirmary, the mischief was probably seated near the origin of the nerve, as it resulted from serious in- jury to the head. A car- riage-horse, belonging to a friend, by exerting con- through an aperture in the partition withdraw it, in consequence of the the aperture. During the efforts to extract it, so much pressure was made upon the portio dura of one side, that the animal lost all power of expression in the corresponding side of the head; the soft parts about the mouth dropped, and the ear no longer associated with that of the opposite side in expression; yet the movements of mastication and deglutition were scarcely affected. This state of paralysis continued for a few days, and gradually disap- peared. Fig. 394 represents a case of paralysis of this nerve, produced Paralysis of the Facial Nerve. siderable power, forced its head of the stall, and was unable to under jaw catching the sides of 1 Dissert. Inaugur., Turin., 1823; cited in Edinb. Med. and Surg. Journ., July, 1834. GESTURES—NERVES OF THE FACE. 347 by the pressure of a tumour beneath the ear; the orbicularis palpebra- rum was paralysed so that the patient was unable to close his eyelids. Independently of the various muscular actions which modify the expression of the human countenance, there are certain others that mark the different mental emotions. The skin varies in colour, be- coming pale or suffused, and frequently alternating rapidly between these two conditions. The changes are more especially witnessed on the forehead, cheeks, and lips ; and arise from an augmented or dimi- nished flow of blood into the capillaries of the part, under the influence of the existing emotion. Under such circumstances, the eye may par- ticipate in the suffusion. The skin may, also, vary in its degree of moisture or heat; it may be dry, or bathed in perspiration; and the perspiration may be warm or cold;—the two conditions occasionally alternating. Particular parts of the face, again, are more susceptible of this " sweat of expression," as it has been termed,—the forehead and temples for example. The heat of the head is also occasionally modi- fied ; a sudden glow is felt in the countenance ; and the expression is sometimes evident to a second person. The expression of the human eye, connected with the action of the oblique muscles, has been referred to under Vision. It was there asserted, that in insensibility, the organ, it has been presumed, is given up to the action of the oblique muscles, and is drawn up under the upper eyelid. The eye itself is, however, capable of various expres- sions, depending upon varied positions of its tutamina; and especially of the secretion from its mucous covering—the conjunctiva,—and from the lachrymal gland; so that it may be swimming, or the tears may flow over the cheeks and constitute weeping. In addition to these, which may be esteemed sources of expression in the human countenance, may be added the action of osculation or hissing; which, wherever practiced, is employed as an expression of love and friendship ;—confined with us to those of the female sex, or of opposite sexes; but, in some countries, employed as an expression of regard between males also. It is impracticable to describe all the facial expressions—Prosoposis, as they have been collectively termed—of which the human countenance is susceptible. They are commonly classed under two heads; the exhi- larating, in which the fsice is flushed, and the countenance expanded;— the muscles being contracted from within to without; and the depress- ing, in which, on the contrary, the face is pale, and the features are drawn inwards and sunken. Let us inquire into the physiology of a few of these expressions; beginning with the play of the features in broad laughter, (Fig. 395,) as being, perhaps, the most easy of explanation. In laughing, it is in vain that we endeavour to confine the lips; a complete relaxation of the orbicularis oris gives uncontrolled power to the opponent muscles inserted into the angles of the mouth and upper lip. Hence, the lateral retraction of the angles of the mouth; the elevation of the upper lip disclosing the teeth; the peculiar elevation of the nostrils without their being expanded, and the dimple of the cheek where the acting muscles congregate: hence, also, the fulness of the cheeks, rising so as to conceal the eye, and throw wrinkles about the lower eyelids 348 MUSCULAR MOTION. and temples. In this ex- pression, the whole of the movable features are raised upwards. The orbicularis palpebrarum does not par- take of the relaxation of the orbicularis oris. It is ex- cited, so as to contract the eyelids, and sink the eye, whilst the struggle of a vol- untary effort of the muscles to open the eyelids, and raise the eyebrow, gives a twinkle to the eye, and a peculiar obliquity to the eyebrow, the outer part of which is most elevated. At the same time, the individual holds his sides, to control the contractions of the muscles of the ribs. The diaphragm is violently agitated. The same influence spreads to the throat, and the sound of laughter is as distinct as the signs in the face. In this movement of expression we have an instance of the asso- ciated action of different parts, which are considered to be under the influence of the respi- Broad Laughter. Fig. 396. Faun Weeping. ratory system of nerves of Sir Charles Bell. The facial expression is under the direction of the portio dura or respiratory nerve of the face. In the face of a faun, (Fig. 396,) sketched by Sir Charles Bell, we have the expression of weeping from pain. In the violence of weep- ing, accompanied with lamentation and out- cry, the face is flushed or suffused from stag- nation of blood in the vessels. The muscles of respiration are af- fected from the com- mencement, and the return of blood from the head is somewhat impeded. The muscles of the cheeks are in movement. Those that GESTURES—CRYING. 349 ■.depress the angles of the mouth are powerfully contracted, and the orbicularis oris is not relaxed, but drawn open by the predominant action of its opponents. A convulsive movement in the muscles about the eyes attends; the eyebrow is drawn down; the eyes are compressed by the eyelids ; the cheek is raised; the nostril drawn out, and the mouth stretched laterally. In weeping, also, unless the con- vulsive movement of the muscles is very strong, the expression of grief affects that part of the eyebrows next the nose. It is turned up with a peevish expression, which corresponds with the depression of the corners of the mouth. This depression gives an air of despondency and languor to the countenance, when accompanied by general re- laxation of the muscles. When the corrugator co-operates, there is mingled in the expression something of mental energy, moroseness, or pain. If the frontal muscle unites its action, an acute turn upwards is given to the inner part of the eyebrow, very different from the effect of the general action of the frontal muscle, and characteristic of anguish, debilitating pain, or discontent, according to the prevailing cast of the rest of the countenance. The depression, however, of the angle of the mouth, that indicates languor and despondency, must be slight; as the depressor anguli oris cannot act forcibly, without the action of the superbus participating—a muscle, which quickly produces a revolu- tion in the expression, and makes the under lip pout contemptuously. The expression at the angles of the mouth demands the careful study of the painter; the most opposite characters being communicated to the countenance by their elevation or depression. When Peter of Cortona was engaged on a picture of the iron age for the royal palace of Pitti, Ferdinand II., who often visited him, and witnessed the progress of the piece, was particularly struck with the exact representation of a child in the act of crying. "Has your majesty," said the painter, "a mind to see how easy it is to make this very child laugh?" The king assented: and the artist, by merely elevating the corner of the lips and inner ex- tremity of the eyebrows, made the child, which at first seemed breaking its heart with weeping, seem equally in danger of bursting its sides with immoderate laughter, after which, with the same ease, he restored to the figure its proper expression of sorrow.1 It is at the angle of the mouth and the inner extremity of the eye- brow that the expression which is peculiarly human is situate. These are the most movable parts of the face. On them the muscles are con- centrated, and it is upon their changes that expression is acknowledged chiefly to depend. All the parts, however, of an impassioned counte- nance are in accordance with each other. When the angles of the mouth are depressed in grief, the eyebrows are not elevated at the outer angles as in laughter. When a smile plays around the mouth, or when the cheek is elevated in laughter, the eyebrows are not ruffled as in grief. In real emotion, these opposite actions cannot be combined; and, when united by the mimic, the expression is farcical and ridiculous. Br. Wollaston2 has shown, that the same pair of eyes may appear to direct themselves either to or from the spectator, by the addition of 1 Good's Book of Nature, iii. 291, Lond., 1834. 2 Philosophical Transactions, for 1824. p. 247; see, also, Letters on Natural Magic, by Sir D. Brewster, Amer. edit., p. 115, New York, 1832. 350 MUSCULAR MOTION. other features in which the position of the face is changed. The nose principally produces the change of direction, as it is more subject to change of perspective than any other feature; and Dr. Wollaston haa shown, that even a small portion of the nose will carry the eyes along with it. He obtained four exact copies of the same pair of eyes look- ing at the spectator, by transferring them upon copper from a steel plate, and having added to each of two pairs of them a nose—in one case directed to the right, and in the other to the left, and to each of the other two pairs a very small portion of the upper part of the nose —all the four pairs of eyes lost their front direction, and looked to the right or to the left, according to the direction of the nose, or of the por- « tion of it that was added. But the effect thus produced is not limited to the mere change in the direction of the eyes; for a total difference of character may be given to the same eyes by a due representation of the other features. A lost look of devout abstraction in an uplifted countenance may be exchanged for an appearance of inquisitive arch- ness in the leer of a younger face turned downwards and obliquely towards the opposite side. This, however, as Sir David Brewster haa remarked, is not perhaps an exact expression of the fact. The new character, which is said to be given to the eyes, is given only to them in combination with the new features; or what is probably more cor- rect, the inquisitive archness is in the other features, and the eye does not belie it. Sir David adds, that Dr. Wollaston has not noticed the converse of these illusions, in which a change of direction is given to fixed features by a change in the direction of the eyes. This effect ia seen in some magic lantern sliders, where a pair of eyes is made to move in the head of a figure, which invariably follows the motion of the eyeballs. In bodily pain, the jaws are pressed together, and there is grinding of the teeth; the lips are drawn laterally, so as to expose the teeth and gums; the nostrils are distended to the utmost, and at the same time drawn up; the eyes are largely uncovered, and the eyebrows elevated; the face is turgid with blood, and the veins of the temple and forehead are distended; the breath being suspended, and the descent of the blood from the head impeded. In anguish, conjoined with bodily suffering, the jaw falls, the tongue is seen; and, in place of the lateral retraction of the lips, the lower lip falls; the eyebrows are knit, whilst their inner extremities are ele- vated ; the pupils of the eyes are in part concealed by the upper eye- lids, and the nostrils are agitated. Agony of mind is here added to the bodily suffering, which is particularly indicated by the change in the eyebrow, and forehead. In rage, the features are unsteady; the eyeballs are largely seen, roll, and are inflamed. The forehead is alternately knit and raised in furrows by the motion of the eyebrows; and the nostrils are inflated to the utmost; the lips are swelled, and, being drawn, open the corners of the mouth. The action of the muscles is strongly marked. The whole countenance is at times pale; at others, inflated, dark and almost livid; the words are passed forcibly through the fixed teeth, and the hair is on end. Fear has different degrees. Mere bodily fear resembles the mean anticipation of pain. The eyeball is largely uncovered; the eyes are GESTURES—FACIAL EXPRESSIONS. 351 staring, and the eyebrows elevated to the utmost stretch. To these are added a spasmodic affection of the diaphragm and muscles of the chest, which affects the breathing, and produces a gasping in the throat, with an inflation of the nostrils, convulsive opening of the mouth, and dropping of the jaw;—the lips nearly concealing the teeth, yet allowing the tongue to be seen, and the space between the nostril and lip being full. There is a hollowness and convulsive mo- tion of the cheeks, and a trembling of the lips and muscles on the sides of the neck. The lungs are kept distended; and the breathing is short and rapid. The surface is pale from the recession of blood; and the hair is lifted up by the creeping of the skin. In fear, where the apprehended danger is more remote, but is approaching, the per- son trembles and looks pale; a cold sweat is on the face; the scream of fear is heard; the eyes start forward; the lips are drawn wide; the hands are clenched, and the expression becomes more strictly animal, and indicative of such fear as is common to brutes. In terror or that kind of fear in which the mind participates more there is a more varying depression in the features, and an action of those muscles, which are peculiar to man, and seem to indicate his superior intelligence and mental feeling. The eye is bewildered; the inner extremity of the eyebrows is turned up, and strongly knit by the action of the corrugator and orbicular muscles; and distracting thoughts, anxiety and alarm are strongly indicated by this expression, which does not belong to animals. The cheek is slightly elevated, and all the muscles, that concentrate about the mouth, are in action. In admiration, the forehead is expanded and unruffled; the eyebrow gently raised; the eyelid lifted so as to expose the coloured circle of the eye, whilst the lower part of the face is relaxed into a gentle smile. The mouth is open; the jaw is a little fallen; and, by the relaxation of the lower lip, we just perceive the edge of the lower teeth and the tongue. In joy, the eyebrow is raised moderately, but without any angu- larity; the forehead is smooth; the eye full, lively and sparkling; the nostril moderately inflated, and a smile is on the lips. This subject is, however, interminable. Enough has been stated to exhibit the anatomy of the varying characters of facial expression. It will be found beautifully treated and illustrated in the work of Sir Charles Bell, to which reference has been made. From all that has been said, it is evident, that the countenance is a good general index of the existing state of the feelings; but farther than this it cannot be depended upon. Yet, in all ages, it has been regarded as the index of individual character. Allusion has been made to the estimate of personal character from the shape of the head, as described by the older poets. Similar indications were conceived to be deducible from the form of the face, expression of the eyes, &c. Thus Shakspeare:— Cleopat. " Bear'st thou her face in mind ? is't long or round ? Messeng. Round, even to faultiness. Cleopat. For the most part, too, They are foolish that are so. Her hair, what colour ? Messeng. Brown, madam, and her forehead As low as she would wish it." Antoxy and Cleopatra, iii. 3, 352 MUSCULAR MOTION. And again:— " Which is the villain ? Let me see his eyes, That when I note another man like him, I may avoid him." Much Ado About Nothing. John Baptist Porta1 and Lavater2 have endeavoured to establish a "science," by which we can be instructed, how to discover the secret dispositions of the head and heart from the examination of particular features. The latter enthusiast, in particular, appears to have carried his notions to the most chimerical extent. " No study," he remarks, " excepting mathematics, more justly deserves to be termed a science than physiognomy. It is a department of physics including theology and belles lettres, and in the same manner with these sciences may be reduced to rule. It may acquire a fixed and appropriate character. It may be communicated and taught." In another place, he remarks, that no person can make a good physiognomist unless he is a well-pro- portioned and handsome man;3 yet he himself was by no means highly favoured in these respects; and it is difficult to say, according to his own theory, how he obtained such progress in the "science"! There is one Fig. 397. Physiognomy of Melancholy. case, and perhaps, one only, in which physiognomy can aid us in the ap- preciation of cha- racter. It has been remarked, that the facial expression may accurately de- pict the existing emotion. If, there- fore, any passion be frequently experi- enced, or become habitual, its charac- ter may remain im- pressed upon the countenance, and admit of an opinion being formed of the individual. No one, who has seen the melancholy mad, can mistake the pi- teous expression produced by brood- ing over the cor- roding idea that en- 1 La Physiognomie Humaine de Jean Baptiste Porta, Rouen, 1655. 2 Works, from the French, by G. Grenville, Esq., Lond. ; or Precis Analytique et Raisonne du Systeme de Lavater, par N. J. Ottin, Bruxelles, 1834. 3 Goods Book of Nature, iii. 309, Lond., 1834. GESTURES. 353 grosses him. In the sketch (Fig. 397), from Sir Charles Bell,1 we have the testy, peevish countenance, bred of melancholy; of one who is incapable of receiving satisfaction from whatever source it may be offered, and who " cannot endure any man to look steadily upon him, even to speak to him, or laugh, or jest, or be familiar, or hem, or point, without thinking himself contemned, insulted, or neglected." Such a countenance no one can misapprehend. In lesser degrees, particular features are found bearing, or seeming to bear, the impress of particu- lar emotions; and, accordingly, we are in the daily habit of forming opinions at first sight, both of the intellectual and moral characteristics of individuals, by the expression of the countenance. Of course, we are frequently led into error; inasmuch as habitual feelings alone are indicated by the physiognomy, whilst the natural disposition may be of an opposite character. The fallaciousness of this mode of judging of mankind has been proverbial in all times. Whenever we attempt to decide upon a man's intellectual powers by the rules laid down by Lavater we are constantly deceived; and, in this respect, he has him- self evidently fallen into gross errors. What may be, not inappropriately, styled "medicalphysiognomy," or the changes of features indicative of, and peculiar to, different diseases and stages of disease, is a subject of moment, and has not met with sufficient attention. In diseases of infancy in particular, the appear- ance of the countenance often materially aids us in discriminating their seat. There is a marked difference between the facial expression of one labouring under violent pain in the head, and of one suffering from excruciating pain in the abdomen, even in the adult. Less degrees of pain are, of course, disregarded; and it is only in severe cases that physiognomy can be inservient to diagnosis; but in the infant, which readily gives expression to pain or uneasiness, the countenance is an excellent medium of discrimination, and frequently indicates, at the first glance, the seat of the derangement. The character, too, of the countenance, in serious disease, as to anxiety, convulsion, &c, is often a subject of watchful interest with the physician.2 Mute expression is not, however, restricted to the face, although, as already remarked, in' civilized man, whose nakedness is covered, we are shut out from the observation of many acts of this nature. During emotion, the skin covering the body may participate with that of the face in its changes from pale to red; and it may be warm or cold; dry or bathed in per- spiration; or, during particular depressing passions, may creep and exhibit the rough character of the cutis anserina or goose skin. Under special emotions, the erectile tissues of the organs of generation, and of the nipple in the female, experience turgescence. All these changes are more or less concealed from view. We are, therefore, more familiar with the sight of phenomena of expression, that affect the whole body, as regards its different attitudes and modes of progression. How tre- mulous and vacillating is the attitude of one labouring under fear; and how different the port of the meek and lowly from that of the proud 1 Anat. of Expression, edit. cit. 2 See, on special medical physiognomy, M. Jadelot, cited by M. de Salle, in Traite des Maladies des Enfans de Michael Underwood, &c.,p. 36 et seq.; and in the author's Commentaries on Diseases of the Stomach and Bowels, p. vii., Lond., 1824. VOL. II.—23 354 MUSCULAR MOTION. and haughty! In walking, we observe a similar difference; and can frequently surmise the passion, whether exhilarating or depressing, under which a person, at a distance, may be labouring, from the cha- racter of his progression. "You may sometimes trace A feeling in each footstep, as disclosed By Sallust, in his Catiline, who, chased By all the demons of all passion^, showed Their work even by the way in which he trode." Byron's "Don Juan." Again, on the communication of sudden tidings of joy, we feel a desire to leap up, and give way to the most wild and irregular motions; whilst the shrinking within ourselves, as it were, and the involuntary shudder, sufficiently mark the reception of a tale of horror. Properly speaking, the subject of cranioscopy belongs to the func- tion of expression, but it has already been considered under another head. Many of the partial movements constitute an important part of the language of expression, especially with the savage, and with those unfortunates who are debarred the advantages of spoken language. In almost all nations, the motions of the head on the vertebral column are used as signs of affirmation or negation;—the former being indi- cated by a sudden and short forward flexion of the head on the column; the latter, by a rapid and short rotation on the axis or vertebra dentata. The shoulders are shrugged in testimony of impatience, contempt, &c. The upper extremities are extensively employed as a part of conven- tional language, and were probably used for this purpose before speech was invented. The open and the closed hands communicate different impressions to the observer; the pointed finger directs attention to the object we desire to indicate, &c. When persons are at such a distance from each other, that the voice cannot be heard, this is the only lan- guage they can have recourse to; and the various important inventions, by which we communicate our feelings to a distance, such as writing and telegraphing, belong to this variety of language. For the deaf and dumb, our ordinary spoken language is translated into gestures, by which a conversation can be held, sufficient for all useful purposes; whilst the deaf, dumb, and blind are mainly restricted to those gestures that are conveyed through their sense of touch. Each acquired gesture is, like each acquired movement of the glottis, an evidence of the possession of intellect. The infant and the idiot have them not, because unable to appreciate their utility. The ges- tures resemble the spoken language in this and many other respects. The eye sees the gesture, to which the intellect attaches an idea as it does to the sound conveyed by the organ of hearing; and the will reproduces the gesture, in the same manner as it reproduces the sound heard. The lower extremities are, also, slightly concerned in the function of expression. They are agitated when impatient, and inces- santly changing their position. The foot is stamped upon the ground in anger; and, like the upper extremity, is employed to convey to the object that has aroused the emotion the most unequivocal evidences of expression. Occasionally, the lower extremity is used as a part of GESTURES—NATURAL SIGNS OF THE PASSIONS. 355 conventional language, as when we tread upon the toes to arouse atten- tion, or to convey insult. Nor are the internal organs foreign to the function of expression. The respiratory movements are affected,—the number of respirations being accelerated or retarded, or manifesting themselves under the different modifications of sighing, yawning, laugh- ing, and sobbing. The heart, too, throbs at times to such an extent, that its action is perceptible externally; or, it may be retarded or hur- ried in its pulsations,—from a state of syncope or fainting to that of the most violent palpitation. Lastly: the excretions, certain of them especially, are greatly impli- cated in many of these moral changes. That of the tears is a well- known and characteristic expression—of grief more especially, but occasionally of joy. The mind, however, may be so possessed by the emotion, that the ordinary power over the sphincter muscles may be more or less destroyed, and the contents of the rectum be spontane- ously evacuated. The action of the stomach is, at times, inverted; and, at others, the peristaltic action is augmented. Who has not felt, whilst labouring under anxiety or dread, the constant desire not only to evacuate the fasces, but also the urinary secretion! It is obvious, from this detail, that there is scarcely a function, which does not express some participation, when the mind is engaged in deep emotion; and that it would be vain to attempt to depict the various forms under which these manifestations may occur. What has been said will suffice to attract attention to the subject, which is not devoid of interest to the anthropologist. In conclusion, we may refer to the question that has often been agi- tated, whether these rapid and violent movements, that characterize the expression of emotions, be instinctive or natural signs of the pas- sion existing in the mind; or whether they be not voluntary muscular exertions, called for by the stress of the case, and constituting the means of resistance, or belonging simply to the outward manifestation of the inward emotion. The supporters of the latter view contend, that the various changes of facial expression or of gesture, which accompany the different mental emotions and indicate their character, are, in all cases, the effect of habit, or are suddenly excited to accom- plish some beneficial purpose. It is difficult, however, to regard the different concomitants of the passion as separate from it. Without them, the expression is incomplete; and, moreover, we observe the different gestures similarly developed in all the various races of man- kind, when affected with the same mental contention. We must, con- sequently, regard the expressions as constituting a natural language, in which each has its appropriate sign; and this view is confirmed by the fact, that there are certain muscles of the face, which seem, in our existing state of knowledge, to be exclusively destined for expression; —those about the eyebrows and angles of the mouth for example. When the triangularis muscle and levator menti combine action, an expression is produced, which is peculiar to man; the angle of the mouth is drawn down, and the lip arched and elevated; hence the most contemptuous and proud expression. A question of a different character has, however, been mixed' up 356 MUSCULAR MOTION. with this:—whether the infant be capable instinctively or naturally of comprehending the difference between the facial expressions of kind- ness or of frowns; some believing, that smiles are merely considered by it to be expressions of kindness, because accompanied by endear- ments,—and frowns to be proofs of displeasure, because followed by punishment. It is certain, however, that the infant interprets the countenance long before it can trace such sequences in its mind; but this does not remove the difficulty. The face of one, whom it has not been accustomed to see, will, at a very early period, impress it unfa- vourably, although the countenance may be unusually prepossessing; and the alteration of the ordinary expression of the maternal counte- nance may be attended with similar results. It is difficult, indeed, to comprehend how the child should be capable of discriminating between the smile and frown, when first presented to it. That organs may be associated in the expression of any encephalic act is intelligible; but that an act of judgment can be executed naturally or instinctively appears inexplicable. Sir Charles Bell,1 who maintains the doctrine of the instinctive character of the expression of human passions, rejects the notion of instinctive expression in the face of the quadruped, con- tending that, even in the passion of rage, which is the most strongly marked of all the changes that occur in the features, are merely mo- tions accessory to the great objects of opposition, resistance, and de- fence. "In carnivorous animals," he remarks, "the eyeball is terrible, and the retraction of the flesh of the lips indicates the most savage fury. But the first is merely the excited attention of the animal, and the other a preparatory exposure of the canine teeth." It appears to be a sufficient answer to this view, that no such expression is ever wit- nessed in other cases of excited attention, or in the simple exposure of the canine teeth, when the animal is devouring its food; unless, indeed, the repast be made during the existence of the passion. On a former occasion, it was remarked, that the encephalon is exclu- sively concerned in the production of the different passions, and that the parts to which they are usually referred, attract our attention to them, principally in consequence of the sensation which accompanies them being there chiefly experienced. The same may be said of the different gestures that accompany the various emotions. They are dependent upon the influence exerted by the function of sensibility on the other functions. Gall,2 in his system, has feebly attempted to show, that each gesture has a reference to the encephalic situation of the organ concerned in the production of the emotion of which it is a con- comitant. The idea was suggested to him, he asserts, by the fact, observed by him a thousand times, that in fractures of the skull, the hand, (naturally we should think,) was carried mechanically to the seat of the fracture. He farther remarks, that the organs of the memory of words and of meditation are seated in the forehead; and that the hand is carried thither, whenever we are engaged in deep study;—that the organ of religious instinct corresponds to the vertex; and hence, in the act of prayer, all the gestures are directed towards that part of 1 Anat. of Expression, edit. cit. 2 Sur les Fonctions du Cerveau, v. 436, Paris, 1825. CILIARY MOTION. 357 the body. Like every professed systematist, Gall is here pushing his principles ad absurdum. They are, indeed, controverted by facts. The hand is usually carried, not to the part of the encephalon in which any passion is effected, but to the part of the body in which its more pro- minent effects are perceptible,—as to the region of the stomach or heart; and frequently the gesture is referable to the determinate action, which must be regarded as a necessary effect of the passion. Finally, sculpture and painting belong properly to the varieties of expression; but they are topics that do not admit of elucidation by physiology. Here terminates the history of the animal functions, which have the common character of being periodically suspended by sleep. By many physiologists, this function has, therefore, been examined in this place; but as the nutritive and generative functions are, likewise, greatly in- fluenced by sleep, we shall follow the example of M. Magendie,1 and defer its study until those functions have been inquired into. 6. CILIARY MOTION. Although not an animal function, it may be convenient to allude, in this place, to the phenomena of vibratory or ciliary motion, which, in recent times, have received the attention of observers. These terms have been employed to express the appearance produced by cilia,—a peculiar sort of mov- ing bodies resembling small hairs, which are visible by the aid of the microscope, on parts that are covered with ciliary or vibratory epithelium.2 This ciliary motion has been seen in different animals, on the external surface, in the aliment- ary canal, the respiratory sys- tem, the female generative or- gans ; and in the cavities of the nervous system. It has not been observed, however, in the va- gina; but may be traced from Cilia. 1. Portion of a bar of the gill of the Mytilis edulis, showing cilia at rest and in motion. 2. Ciliated epi- thelium particles from frog's mouth. 3. Ciliated epi- thelium particle from inner surface of human mem- brana tympani. 4. Ditto, ditto: from the human bronchial mucous membrane. 5. Leucophryspatula, a polygastric infusory animalcule; to show its sur- the lips of the" os uteri through ^ceemc.overed with cilia'and the mouth surr0UIlded ^ its cavity, and through the Fal- lopian tubes to their fimbriated extremities, and Virchow observed it over the surface of all the cerebral ventricles, but it was not marked 1 Precis E16mentaire, i. 366. 2 Sharpey, art. Cilia, Cyclop, of Anat. and Physiol., P. vi., p. 606, Lond., 1836 ; and Henle, Allgem. Anat., or Jourdan's French Translation, p. 251, Paris, 1843; and the excellent article Flimmerbewegung, by Valentin, in Wagner's Handworterbuch der Physiologie, 3te Lieferung, S. 484, Braunschweig, 1842. 358 CILIARY MOTION. in the fourth ventricle. Kolliker,1 however, sought for cilia in vain in the ventricular epithelium of an executed criminal. In the upper classes of animals, it is not witnessed on the external surface except in the embryo. In most ani- Fig- 399. mals, a high magnifying power is necessary to perceive it. A small piece of mucous mem- brane, on which it exists, should be moistened with water, and covered with a plate of glass, by Vibratile or Ciliated Epithelium. which t]f membrane is spread out, and its border rendered a. Nucleated cells, resting on their smaller extre- i i • -t_i Tir-j.T_ ±i • i p mities. b. cilia. clearly visible. With the aid of a powerful microscope, an ap- pearance of undulation is perceptible, and small bodies floating in the water may be seen, near the border of the membrane, to be driven along in a determinate direction. With a still higher magnifying power, the cilia themselves may sometimes be recognized, although seldom very distinctly, owing to the great rapidity of their motion. The influence of the motion on the fluids and small bodies in contact with the membrane may be well exhibited by strewing a fine powder on the surface; as the motion of the cilia has a uniform direction, it gives rise to currents over the surface of the membrane. An easy mode of observing the phenomenon is to scrape with a knife a few scales of epithelium from the back of the throat of a living frog. If these be moistened with water or serum, they will continue to exhibit the motion of the adherent cilia for a very considerable time, if the epithelium be only kept moistened. On one occasion, Messrs. Todd and Bowman observed a piece of epithelium prepared in this manner exhibit motion for seventeen hours; and they thought it would probably have done so for a longer time had not the moist- ure around it evaporated. In the turtle, after death by decapitation, MM. Purkinje and Valentin found it lasted in the mouth nine days; in the trachea and lung, thirteen days; and in the oesophagus, nine- teen days.2 According to M. Donne,3 cilia are seen only on the " true mucous membranes" of his division,4 or those that secrete an alkaline mucus. They are never met with on the acid membranes, which are analogous to the skin, and simple reflections of the cutaneous envelope. Hence, they are not found in the mouth or vagina, but in the nasal and bron- chial mucous membrane. The organs of ciliary motion are delicate transparent filaments, varying in length, according to Purkinje and Valentin, from T3^B7 to T Jfg of an inch, and are generally thicker at the base than at the free extremity. Their motion continues after death as long as the tissues 1 Goodsir's Annals of Anatomy and Physiology for May, 1852, No. 2, p. 113. 2 Physiological Anatomy and Physiology of Man, by Messrs. Todd and Bowman, p. 62, Lond., 1843. 3 Cours de Microscopie, p. 170, Paris, 1844. 4 See Secretion of Mucus in vol. i., p. 502 of this work. CILIARY MOTION. 359 retain their contractility, and often much longer. Miiller1 thus sums up the present state of our knowledge in regard to the phenomenon. That the ciliary motion of the mucous membranes is due to the action of some unknown contractile tissue, which lies either in the substance of the cilia or at their base,—that this tissue resembles in contractility the muscular and other contractile tissues of animals;—that its pro- perties so far agree with those of the muscular tissues—at all events with those of the involuntary muscles of the heart, and the vibratory laminae of the lower Crustacea;—that the motions, which it produces, continue without ceasing with an equable rhythm;—that its properties a°ree also with those of the muscular tissue of the heart in its motions, continuing long after the separation of the part from the rest of the animal body;—that this tissue differs essentially, however, from muscle, in the circumstance of its motions not being arrested by the local ap- plication of narcotics; and lastly, that the ciliary motion presents itself under conditions where it is not probable that a complicated organization exists,—namely, in the undeveloped embryos of polypifer- ous animals. M. Donne'2 regards the cilia as animalcules; resembling in many respects the spermatozoids. They certainly resemble each other; but there is no sufficient reason to believe either of them animalcular. The production of currents by the ciliary motion is not easy of ex- planation. Purkinje and Valentin ascribe them to the return of the cilia from the bent to the erect state, which gives an impulse to the fluid. The direction in which the cilia act is most commonly towards the outlet of the canal on which they are placed; but, as Mr. Paget3 has remarked, their special purpose is in many instances—for example, in the ventricles of the brain—as uncertain as the power by which they act. 1 Elements of Physiology, by Baly, P. iv. p. 866, Lond., 1838. 2 Op. cit., p. 176. 3 Brit, and For. Med. Review, July, 1842, p. 264. 360 GENERATION. BOOK III. REPRODUCTIVE FUNCTIONS. The functions, which we have been hitherto considering, relate ex- clusively to the individual. We have now to investigate those that refer to the preservation of the species, and without which living beings would soon cease to exist. Although these functions are really multiple, it has been the custom with physiologists to refer them to one head—generation—of which they are made to form the subordi- nate divisions. CHAPTEE I. GENERATION. The function of generation, much as it varies amongst organized bodies, is possessed by them exclusively. When a mineral gives rise to another of a similar character, it is at the expense of its own exist- ence ; but the animal and the vegetable produce being after being without any curtailment of theirs. The writers of antiquity considered, that all organized bodies are produced in one of two ways. Amongst the upper classes of both animals and vegetables, they believed the work of reproduction to be effected by a process, which is termed univocal or regular generation,— generatio homogenea, propagatio; but in the very lowest classes, as the mushroom, worm, frog, &c, they conceived that the putrefaction of different bodies, aided by the influence of the sun, might generate life. This has usually been termed equivocal or spontaneous generation,—gene- ratio heterogenea, cequivoca, primitiva, primigena, originaria, spontanea. By some, however, spontaneous generation is made to include the pro- duction of living beings from the mere combination of inorganic ele- ments ; whilst by equivocal generation is meant their evolution from organized beings dissimilar to themselves, through irregularity in their functions, or the incipient decay or degeneration of their tissues. The doctrine of spontaneous generation is supposed to have been devised by the Egyptians to account for the swarms of frogs and flies, which appeared on the banks of tKe Nile after its periodical inundations.' Amongst the ancients, the latter hypothesis was almost universally credited. Pliny unhesitatingly expresses his belief, that the rat and frog are produced in this manner; and in his time it was generally thought, that the bee, for example, was derived at times from a parent; ' Fleming's Philosophy of Zoology, i. 24, Edinb., 1822. GENERATION. 361 but at others from putrid beef.1 The passage of Virgil2—in which he describes how the shepherd Aristaeus succeeded in producing swarms of bees from the entrails of a steer, exposed for nine days to putre- faction—is probably familiar to most readers, and exhibits the same belief. The hypothesis of equivocal generation having been conceived in consequence of the impracticability of tracing ocularly the function jn the minute tribes of animals, it naturally maintained its ground unin- terruptedly, as regarded those animals, until better means of observa- tion were invented. The difficulty of admitting regular generation as applicable to all animals was augmented by the fact, not at first known to naturalists, that many of the lower tribes conceal their eggs, in order that their nascent larvas may find suitable food; but the existence of evident sexual organs in many of these small species induced physiolo- gists, at an early period, to believe, that they also might be reproduced by sexual intercourse: direct proofs were not, however, obtained until the discovery of the microscope; after which the investigations of Eedi, Vallisnieri, Swammerdam, Hooke, Keaumur, Bonnet, and others, clearly demonstrated, that many of the smallest insects have eggs and sexes, and reproduce like other animals. In the case of plants it has been supposed, that the growth of fungi amongst dung, and of the various parasitical plants that appear on putrid flesh, fruit, &c, furnishes facts in support of the equivocal theory; but the microscope exhibits the seeds of many of these plants, and experiments show them to be pro- lific. The characters, by which the different species and varieties are distinguished, although astonishingly minute, are fixed, exhibiting no fluctuation, such as might be anticipated did the plants arise by spon- taneous generation, or by the fortuitous concourse of atoms. The animalcules, that make their appearance in water in which vege- table or animal substances have been infused or are contained, would seem, at first sight, to favour the ancient doctrine. In these cases, however, the species, again, have determinate characters; presenting always the same proportion of parts; and appearing to transmit their vitality to their descendants in a manner not unlike animals and vege- tables higher in the scale. The explanation, offered by the supporters of the univocal theory for those obscure cases, in which direct observa- tion fails us, is, that their seeds and eggs are so extremely minute, that they can be borne about by the winds, or by birds; be readily depo- sited; and, when they find a soil or nidus favourable to their growth, undergo developement. Thus, the soil, in which alone the monilia glauca flourishes, is putrid fruit; whilst the small infusory animal— vibrio aceti or vinegar eel—requires, for its growth, vinegar that has been for some time exposed to the air.3 "That the atmosphere," says Dr. Good,4 "is freighted with myriads of insect eggs, that elude our senses; and that such eggs, when they meet with a proper bed, are hatched in a few hours into a perfect form, is clear to any one who has 1 "Apes nascuntur partim ex apibus, partim ex bubulo corpore putrefacto."—Varro, De Re Rustica, iii. 16. See, also, Plinii Hist. Natural. 2 Georgic, lib. iv. 1. 295. See, also, J. B. Porta, Magise Naturalis libri viginti, cap. 2. i:Animalia qutedam terrestria, quse ex putrefactione gignuntur." Lugd. Bat., 1644. 3 Fleming, op. citat., p. 24. 4 Study of Medicine, CI. i. Ord. 1, Gen. x. Sp. 3. 362 GENERATION. attended to the rapid and wonderful effects of what, in common lan- guage, is called a blight, upon plantations and gardens. I have seen, as probably many, who may read this work, have also, a hop-ground completely overrun and desolated by the aphis humuli or hop green- louse, within twelve hours after a honey-dew (which is a peculiar haze or mist, loaded with a poisonous miasm) has slowly swept through the plantation, and stimulated the leaves of the hop to the morbid secretion of a saccharine and viscid juice, which, while it destroys the young shoots by exhaustion, renders tbem a favourite resort for this insect, and a cherishing nidus for the myriads of little dots that are its eggs. The latter are hatched within eight-and-forty hours after their deposit, and succeeded by hosts of other eggs of the same kind; or, if the blight takes place in an early part of the autumn, by hosts of the young insects produced viviparously; for in different seasons of the year, the aphis breeds both ways. Now it is highly probable, that there are minute eggs or ovula of innumerable kinds of animalcules floating in myriads of myriads through the atmosphere, so diminutive as to bear no larger proportion to the eggs of the aphis than these bear to those of the wren, or the hedge-sparrow; protected, at the same time, from destruction by the filmy integument that surrounds them, till they can meet with a proper* nest for their reception, and a proper stimulating power to quicken them into life; and which, with respect to many of them, are only found obvious to the senses in different descriptions of animal fluids. The same fact occurs in the mineral kingdom: stagnant water, though purified by distillation and confined in a marble basin, will, in a short time, become loaded on its surface or about its sides with various species of confervas; while the interior will be peopled with microscopic animalcules. So, while damp cellars are covered with boletuses, agarics and other funguses, the driest brick walls are often lined with the lichens and mosses. We see nothing of the animal and vegetable eggs or seeds by which all this is effected; but we know, that they exist in the atmosphere, and that this is the medium of their circulation." Any difficulty that might exist in re- gard to the transmission of such minute bodies through the atmosphere is removed, when we reflect on the extreme diffusion of odours, and on the fact that particles of sand are transmitted hundreds of miles from their original seat (see vol. i. p. 718). In dust, which was collected on a vessel three hundred miles from the land, Mr. Darwin1 was much surprised to find particles of stone above the thousandth of an inch square, mixed with finer matter. The view of the extraneous origin of the seeds of the confervse, &c, is corroborated by an experiment of Senebier. He filled a bottle with distilled water, and corked it accurately; not an atom of green matter was produced, although it was exposed to the light of the sun for four years; nor did the green matter, considered as the first stage of spon- taneous organization, exhibit itself in a glass of common water, covefed with a stratum of oil. It is proper, however, to remark, that the ob- servation of others invalidates the results of this experiment; and, 1 Journakof Researches into the Natural History and Geology of the Countries visited during the Voyage of H. M. S. Beagle round the World, by C. Darwin, M. A., F. R. S., Amer. edit., p. 7, New York, 1846. OF ENTOZOA. 363 moreover, it has been said, that if the fact be admitted, the exclusion of air might have prevented some simple condition necessary for the aboriginal developement of life. Burdach,1 assisted by Hensche, and along with Professor von Baer, poured water on marble in a glass vessel, the remainder of the vessel being filled with atmospheric air, oxygen or hydrogen; and placed it in the light of the sun, or in warm sand. No green matter was perceptible, but there was a slimy sub- stance with white threads, part of which had a ramified appearance, and part that of coral. On the other hand, pieces of granite, newly broken from the midst of a block, produced—with fresh distilled water, and oxygen or hydrogen, in the sun—green matter, with threads of confervas; but in the warmth of digestion flocculi only. He next took some mould, which he dug up, and which was inodor- ous, and apparently free from all foreign matter; boiled it in a con- siderable quantity of water, and reduced the decoction to the consist- ence of a thick, partly pulverulent extract. This gave, with common water and atmospheric air—in bottles with ground stoppers, tied over with bladder—in the sun, numerous infusory animalcules and green matter; but with distilled water and oxygen or hydrogen, green mat- ter only appeared at the bottom of the bottles. The subject of intestinal worms has been eagerly embraced by the supporters of the doctrine of equivocal generation, who are of opinion, that the germs need not be received from without; whilst the follow- ers of the univocal doctrine maintain, that they must always be ad- mitted into the system. The first opinion includes amongst its sup- porters the names of Needham,2 Buffon, Patrin, Treviranus,3 Budolphi,4 Bremser,5 Himly, and other distinguished helminthologists. The latter comprises those who believe in the Harveian maxim,—the only one that can be admitted,—omne vivum ex ovo.6 To support the latter opinion, it has been attempted to show, that the worms, found in the human intestines, are precisely the same as others that have been found out of the body; but the evidence in favour of this position is by no means strong or satisfactory. Linnaeus affirms, that taenia vul- garis,—of a smaller size, however,—has been met with in muddy springs; and ascarides vermiculares in marshes, and the putrescent roots of plants. Gadd affirms, that he met with tcenia articulata plana osculis lateralibus geminis in a chalybeate rivulet; Unzer, tcenia in a well; and Tissot says, that he found tcenia, exactly like the human, in a river; whilst Linnseus, Leeuenhoek, Schaffer and others affirm, that they have found distoma hepaticum in water; but 0. F. Miiller,—who took extraordinary pains in the comparative examination of the en- tozoa that infest the human body, and those met with in springs,— states, that he has frequently detected planarice, but never saw one like the distoma hepaticum.1 1 Die Physiologie als Erfahrungswissenschaft, 2te Auflage, i. 23, Leipz., 1835. 2 An Account of some New Microscopical Discoveries, 8vo., Lond., 1745. 3 Biologie, ii. 264. 4 Entozoorum sive Vermium Intestinalium Historia Naturalis, i. 370. 1 Ueber Lebende Wiirmer im Lebenden Menschen, Wien, 1819. 6 " La vie ne nait que de la vie. Tout etre vivant vient d'un parent." Flourens, De la Longevite Humaine et de la Quantite de Vie sur le Globe, 2de edit., p. 166, Paris, 1855. ^ 7 Rudolphi, op. citat. 364 GENERATION. On the other hand, the supporters of the equivocal theory have laboured, with a good deal of success, to show, that a difference is always discoverable between the worms found without, and those found within, the body; but were it demonstrated to a mathematical certainty, that such difference exists, it would not be an invincible argument against the correctness of the univocal theory; as differences of locality, food, &c, might induce important changes in their corporeal develope- ment, and give occasion to the diversity occasionally perceptible amongst these parasites. Yet if we admit, that the germs of the entozoa are always received from without, their occurrence in different stages of developement in the foetus in utero is a circumstance difficult of expla- nation. Small, indeed, must be the germ, which, when received into the digestive organs of the mother, can pass into her circulation, be transmitted into the vessels of the foetus; be deposited in some viscus, and there undergo its full developement; yet such cases have occurred, if the theory be correct. Certain it is,—howsoever the fact may be accounted for,—that worms have been found in the foetus by indivi- duals whose testimony cannot be doubted. Eschholz saw them in the egg of the hen. Fromann found distoma hepaticum in the liver of the foetal lamb; Kerckring,1 ascarides lumbricoides in the stomach of a foetus six and a half months old; Brendel, tcenice in the human foetus in utero; Heim, tcenice in the new-born infant; Blumenbach, tcenice in the intes- tine of the new-born puppy; and Goze, Bloch, and Eudolphi, the same parasite in sucking lambs. Perhaps the conclusion of Cuvier2 is most consistent with analogy, —that these parasites " propagate by germs so minute as to be capable of transmission through the narrowest passages; so that the germs may exist in the infant at birth." We have seen, however, that not simply the germs, but the animals themselves have been found at this early period of existence. The scientific world was, at one time, astounded by the assertion of Mr. Crosse, that he had succeeded in forming infu- sory animalcules from solutions of granite, silex, &c, by the aid of galvanism. He was engaged in some experiments on crystallization, in which a powerful galvanic battery was made to act upon a saturated solution of silicate of potassa, when the insects made their appearance. He subsequently employed nitrate of copper—a poison to mammalia— and from it also the insects emerged. Some years afterwards, these experiments were repeated by Mr. Weekes, of Sandwich, England, and with the same results. Besides employing silicate of potassa, Mr. Weekes tried ferrocyanuret of potassium, on account of its con- taining a larger proportion of carbon, a principal element of organ- ized bodies; and from this the insects were produced in increased numbers. The insects observed by both experimenters appear to have been the same—a species of acarus, minute, semi-transparent, and furnished with long bristles, which can only be seen by the aid of the microscope. The only satisfactory mode of explaining the phenomenon—difficult 1 Spicilegium Anatom. Obs., lxxix. p. 154. Amstel., 1670. 2 Regne Animal, p. 27. See, also, Vogel, The Pathological Anatomy of the Human Body, by Day, p. 454, Lond., 1847, or Amer. edit., Philad., 1847. OF ENTOZOA. 365 of conception under any aspect—is, that ova were existent in the solu- tions, which became developed under the galvanic influence. It has been plausibly argued, however, that the Acarus Crossii was a type of being ordained from the beginning, and destined to be realized under certain physical conditions. "When a human hand," observes an ingenious and able writer,1 " brought these conditions into the proper arrangement, it did an act akin to hundreds of familiar ones which we execute every day, and which are followed by natural results; but it did nothing more. The production of the insect, if it did take place as assumed, was as clearly an act of the Almighty himself, as if he had fashioned it with his hands. For the presumption, that an act of aboriginal creation did take place, there is this to be said, that, in Mr. Weekes's experiments, every care that ingenuity could devise, was taken to exclude the possibility of a developement of the insects from ova. The wood of the frame was baked in a powerful heat; a bell-shaped glass covered the apparatus, and from this the atmosphere was excluded by the constantly rising fumes from the liquid, for the emission of which there was an aperture so arranged at the top of the glass, that only these fumes could pass. The water was distilled and the substance of the silicate had been subjected to a white heat. Thus, every source of fallacy seemed to be shut off. In such circumstances, a candid mind, which sees nothing impious or unphilosophical in the idea of a new creation, will be disposed to think, that there is less diffi- culty in believing in such a creation having actually taken place, than in believing that in two instances, separated in time and place, exactly the same insects should have chanced to arise from concealed ova, and these a species heretofore unknown." For years, we are informed,2 Mr. Weekes continued to subject solutions to electric agency, and in- variably found insects produced in them, whilst they as invariably failed to appear where electric action was not employed, but every other condition was fulfilled. It is stated, however, in answer to these expe- riments, that specimens of the insects were sent to Paris, and found to contain ova; and that other specimens sent to London were dipovered not to be a new species, but one abundant in the country,—" the acarus horridus, which abounds in dirty shops, dusty shelves, and damp outhouses; and having a taste for pure physics, is especially abundant in all laboratories, and among the bottles of a chemist's shop."!3 Another series of facts has been brought forward as deserving not less attention than those already mentioned, and which would seem to show, that new species of animals may result from new circumstances. The pig, in its domestic state, is subject to the attacks of hydatids, from which the wild animal is free, and which constitute the "measles" in pork; and it is argued that as the domestication of the pig is com- paratively a recent event, the hydatid must likewise be of recent origin. So, also, there is a tinea, which attacks dressed wool, but never touches it in its unwashed state. A particular insect disdains all food but 1 Vestiges of the Natural History of Creation, Amer. edit., p. 143, New York, 1845. 2 Sequel to Vestiges of the Natural History of Creation, p. 85, New York, 1846. 3 Edinburgh Review, for July, 1845, Amer. edit., p. 38. 366 GENERATION. chocolate, and the larva of the oinopota cellaris lives no where but in wine and beer—all articles manufactured by man.1 The subject is in- volved in difficulties; yet the univocal theory is, in all respects per- haps, most admissible as regards the whole living creation. " That all animals are produced from eggs (pmne vivum ex ovo)" says Pro- fessor Agassiz,2 " is an old adage in zoology, which modern researches have fully confirmed." Still, there are many distinguished naturalists who esteem it probable, that spontaneous generation may occur in the lowest divisions of the animal series. Amongst these may be men- tioned De Lamarck, Easpail, Burdach, Treviranus, Wrisberg, Schweig- ger, Gruithuisen, Von Baer,—and M. Adelon seems to accord with them. The facts that have been observed, of late, of certain parasites, as the Cercaria, insinuating themselves into the skin and cavities of animals, as well as phenomena like the following, are favourable to the former view. At certain periods of the year, the sculpins of the Baltic are infested by a particular species of taenia, from which they are free at other seasons. Mr. Eschricht observes, that at certain seasons these worms lose a great portion of the long chain of rings of which they are composed; and on a careful examination each ring is found to contain several hundred eggs, which, on being freed from their envelope, float in the water, and are doubtless swallowed by the sculpins, in which, finding a nidus favourable to their developement, the species is propa- gated, and transmitted from one generation of the fish to another.3 AH animals may swallow, in like manner, in their food and the water they drink, numerous eggs of parasites, which may become developed internally when the nidus is favourable to them; and it is probable that the intestines of man afford such a nidus only for the entozoa with which he is known to be infested; and hence we can account for the different parasites that are met with in different animals.4 The views of M. De Lamarck5 regarding the formation of living bodies are strange in the extreme; and exhibit, what we so frequently witness, that, in order to get rid of a subject difficult of comprehension, the philosopher frequently adopts suppositions, that require a much greater sketch of the imagination to invent, and present stronger ob- stacles to belief, than those for which they may have been substituted. M. De Lamarck maintains, that the first organized beings were formed throughout by a true spontaneous generation,—their existence being owing to an excitative cause of life, furnished probably by the circum- ambient medium, and consisting of light and electric fluid. When this cause meets with a substance of a gelatinous consistence, dense enough to retain fluids, it organizes it into areolar tissue; and a living being results. This process, according to De Lamarck, is occurring daily at the extremity of the vegetable and animal kingdoms. The being, thus formed, manifested originally, according to him, three faculties of life,—nutrition, growth, and reproduction; but only in the most simple 1 Vestiges, &c, p. 139. 2 Principles of Zoology, by Louis Agassiz and Augustus A. Gould, p. 103, Boston, 1848. 3 Ibid., p. 141. * See, on the whole subject of the origin of life— Ursprung des Lebens—Eschricht, Das Physische Leben, S. 98, Berlin, 1852. 6 Philosophic Zoologique, vol. i., Paris, 1830 KINDS OF GENERATION. 367 manner. The organization soon, however, became more complicated, for it is, he remarks, a property of the vital movement to tend always to a greater degree of developement of organization; to create particu- lar organs, and to divide and multiply the different centres of activity; and, as reproduction has constantly preserved all that had been ac- quired, numerous and diversified species have in this manner been formed, possessing more and more extensive faculties. So that, ac- cording to this system, nature was directly concerned only iri the first draughts of life; and participated indirectly in the existence of living bodies of a more complex character; and these proceeded from the former, after a lapse of an enormous time, and an infinity of changes in the incessantly increasing complication of organization;—repro- duction continuing to preserve all the acquired modifications and im- provements. The simplest kind of generation does not require sexual organs. The animal, at a certain period of existence, separates into several fragments, which form so many new individuals. This is called fissipa- rous generation or generation by spontaneous division. We have exam- ples of it in the infusory animalcules,—as in vibrio aceti, the vinegar eel. A somewhat more elevated kind of reproduction is the gemmipa- rous,—common in the vegetable kingdom,—which consists in the forma- tion of buds, sporules, or germs on some part of the body. These, at a particular period, drop off, and form as many new individuals; and, according as the germs are developed at the surface of the body, or internally, gemmiparous generation is said to be external or internal. In these two varieties, the whole function is executed by a single indi- vidual. Higher up in the scale, we find special organs—male and female—for the accomplishment of generation. In animals, however, that possess special reproductive organs, some have both sexes in the same individual or are hermaphrodite or androgynous, as is the case with almost all plants,' and some of the lower tribes of animals. In these, again, we notice a difference. Some are capable of reproduction without the concourse of a second individual; others, although possess- ing both attributes, require the concourse of another; the male parts of the one uniting with the female parts of the other. Both, in this way, become impregnated. The helix hortensis or garden snail affords us an instance of this kind of reproduction. They meet in pairs, accord- ing to Shaw,1 and, stationing themselves an inch or two apart, launch several small darts, not quite half an inch long, at each other. These are of a horny substance, and sharply pointed at one end. The ani- mals, during the breeding season, are provided with a little reservoir for them, situate within the neck, and opening on the right side. On the discharge of the first dart, the wounded snail immediately retaliates on its aggressor by throwing a similar dart; the other renews the bat- tle and is wounded in turn. When the darts are expended, the war of love is completed, and its consummation succeeds. In the superior animals, each sexual characteristic is possessed by a separate individual,—the species being composed of two beings, male and female; and the concourse of the two, or of matters proceeding 1 Zoology, or Systematic Natural History, Lond., 1800. 368 GENERATION. from them, being absolutely necessary for reproduction. But here again, two great differences are met with in the process. Sometimes the fecundating fluid of the male is not applied to the ovum of the female, until after its ejection by the latter, as in fishes.1 In other cases, the ovum cannot be fecundated after its ejection, and the fluid of the male sex is applied to it whilst still within the female—as in birds and the mammalia. In such case, the male is furnished with an organ for penetrating the parts of the female, and in this kind of generation there must be copulation. Again, where there is copulation, the following varieties may exist. First. The ovum, when fecundated, may be immediately laid by the female, and be hatched out of the body,—constituting oviparous gene- ration. Secondly. Although the process of laying may commence immediately, the fecundated ovum may pass so slowly through the excretory passages that it may be hatched there; and the new indi- vidual issue from the womb of the parent possessing the proper forma- tion. This constitutes ovo-viviparous generation, of which Ave have examples in the viper and salamander. Thirdly. The fecundated ovum may be detached from the ovary soon after copulation; but, in place of being ejected, may be deposited in a reservoir, termed a womb or uterus ; be fixed there; attract fluids from the organ adapted for its developement; and thus, increasing at the expense of the mother, be hatched, as it were, in this reservoir so that the new being may be born under its appropriate form. In such case, it may be supported for a time, after birth, on a secretion of the mother—the milk. These circumstances constitute viviparous generation ; in which there are copu- lation, fecundation, gestation or pregnancy, and lactation or suckling. Lastly. There are animals, which, like the kangaroo, opossum, and wombat, are provided with abdominal pouches—marsupia—into which the young, born at a very early stage of developement, are received; and nourished with milk secreted from the glands contained within these pouches. Such animals are termed marsupial or marsupiate. There is much difference in animals as regards the nurturing care afforded by the parents to their young. Amongst oviparous animals, many are satisfied with instinctively depositing their ova in situations and under circumstances favourable to their being hatched, and aban- doning them, so that they can. never know their progeny. This is the case with insects. Others, again, as birds, subject their ova to incuba- tion ;. and, after they have been hatched, administer nourishment to their young during the early period of existence. In the viviparous animal, these cares are still more extensive,—the mother drawing from her own bosom the nutriment needed by the infant, or suckling it. 1 The artificial fecundation of fish has of late years received much attention, with the view of introducing valuable species into streams where they have not previously existed, or do not abound. It is but necessary, that the roe of the female, and the melt of the male, shall be brought in contact under favourable circumstances. Professor Coste, who has been employed by the French government on the important subject of pisciculture, exhibited to the author, in the summer of 1854, numerous salmon, in various stages of their growth, which had been raised by him in this manner. In- structions Pratiques sur la Pisciculture suivies de Memoires et de Rapports sur le MSme Sujet. Par M. Coste, Membre de I'lnstitut, &c, Paris, 1853. Translated by W. H. Fry, New York, 1854. KINDS OF GENERATION. 369 There are yet other varieties in the generation of animals. In some, it can be performed but once during the life of the individual; in others, it can be effected repeatedly. At times, one copulation fecun- dates only a single individual; at others, several generations. A fami- liar example of this fecundity occurs in the common fowl, in which a single access may be sufficient to fecundate the eggs for a season. In the°insect tribe, this is still more strikingly exemplified. In the aphis puceronor green plant louse, through all its divisions; and in the mono- cuius pulex, according to naturalists, a single impregnation suffices for at least six or seven generations. There is, in this case, another strange deviation from the ordinary laws of propagation,—that in the warm summer months the young are produced viviparously; and in the cooler autumnal months oviparously. A single impregnation of the queen bee serves to fecundate all the eggs she may lay for two years at least,—Huber1 believes for the whole of her life, but he has had numerous proofs of the former. She begins to lay her eggs forty-six hours after impregnation; and commonly lays about three thousand in two months, or at the rate of fifty daily. The young, again, are some- times born with the shape they have always to maintain; at others, under forms that are subsequently modified materially, as in the papilio or butterfly genus;—and, lastly;—many naturalists admit a series of cases in which the young not only do not resemble the parent at birth, but remain dissimilar during their whole life, so that their relationship is not apparent until a succeeding generation. The son resembles not the father, but the grandfather; and in some cases the resemblance does not reappear until the fourth or fifth generation, and even later. This strange variety of propagation has received the name of alternate reproduction or generation and metagenesis? The phenomena presented by it have been much studied of late, by Professors Agassiz, Carpen- ter,3 and others. Among the parasitic worms is one known under the name Cercaria, which attaches itself to fresh-water shells, particularly the Lymnea and Paludina; and soon becomes changed into the Dis- toma or Fluke; so that the Cercaria can only be considered as the larve of the Distoma; and farther investigation exhibits even larves to the Cercaria themselves. Among the aphides the number of gene- rations is still greater. The first generation, which is produced from eggs, soon undergoes metamorphosis, and gives birth to a second gene- ration, which is followed by a third, and so on; so that it is not at times until the eighth or ninth generation, that the perfect animal appears as male and female,—the sexes being for the first time distinct, and the male provided with wings. The female lays eggs, which are hatched the following year to undergo a similar succession.4 It has been recently proved experimentally by Kuchenmeister,5 that cysticercus cellulosse becomes transformed into tasnia solium in 1 Nouvelles Observations sur les Abeilles, Paris, 1814. 2 Steenstrup on the Alternation of Generations (Generations Wechsel), English edi- tion by the Ray Society, London, 1845. 3 Principles of Comparative Physiology, Amer. edit., p. 481, Philad., 1854. 4 Agassiz and Gould, op. cit., p. 131. See, also, Allen Thomson, art. Ovum, in Cy- clop, of Anat. and Physiol., pt. xliii., p. 24, September, 1852. 5 Correspond. Blatt. der Verein. fiir gemein. Arbeit. S. 158, No. 13, 1855 ; and Brit. and For. Med.-Chir. Rev., Jan., 1856, p. 238. VOL. II.—^4: 370 GENERATION. the intestinal tube of man. A criminal received with his food a num- ber of cysticerci, 72, 60, 36, 24 and 12 hours before his death. On examining his body, forty-eight hours after execution, ten young taenise were found in the duodenum. Eeproduction in the human species requires the concourse of both sexes; the sexes being separate, and each possessed by a distinct indi- vidual—male and female. All the acts comprising it may be referred to five great heads. 1. Copulation, the object of which is to apply the fecundating germ, furnished by the male, to that of the female. 2. Conception or fecundation, the prolific result of copulation. 3. Gesta- tion or pregnancy, comprising the sojourn of the fecundated ovum in the uterus, and the developement it undergoes there. 4. Delivery or accouchement, which consists in the detachment of the ovum; its excre- tion, and the birth of the new individual: and lastly, lactation, or the nourishing of the infant on the maternal milk. 1. GENERATIVE APPARATUS. The part, taken by the two sexes in the process of generation is not equally extensive. Man has merely to furnish the fluid necessary for effecting fecundation, and to convey it within the female. He, conse- quently, participates only in copulation and fecundation; whilst, in addition, the acts of gestation and lactation are accomplished by the female. Her generative apparatus is therefore more complicated, and consists of a greater number of organs. a. Genital Organs of the Male. The generative apparatus of the male comprises two orders of parts: —1. Those which secrete and preserve the fecundating fluid, and those which accomplish copulation. The first consists of two similar glands—testes—which secrete the sperm or fecundating fluid from the blood. 2. The excretory ducts of those glands—vasa deferenlia. 3. The vesiculoe seminales, which communicate with the vasa deferentia and urethra; and 4. Two canals, called ejaculatory, which convey the sperm from the vesiculse seminales into the canal of the urethra, whence it is afterwards projected externally. The second consists of the penis, an organ essentially composed of erectile tissues, and capable of acquiring considerable rigidity. The several parts will require a more detailed notice. Testes.—The testicles are two glands situate in a bag suspended beneath the pubes, called scrotum; the right being a little higher than the left. They are of an ovoid shape, compressed laterally,—their size being usually that of a pigeon's egg, and weight about seyen and a half or eight drachms:—Sir A. Cooper1 says about an ounce; and Mr. Curling2 six drachms. The left testis is generally larger than the right. Like other glands, they receive arterial blood by an appropri- ate vessel, which communicates with the excretory duct. The sper- matic artery conveys the blood, from which the secretion has to be formed, to the testicle. It arises from the abdominal aorta at a very 1 Observations on the Structure and Diseases of the Testis, Amer. edit., p. 25, Philad., 1845. 2 Practical Treatise on Diseases of the Testis, &c, p. 9, Lond., 1843. GENERATIVE APPARATUS—MALE. 371 acute angle; is small, extremely tortuous, and passes down to the ab- dominal ring, through which it proceeds to the testicle. _Wnen it reaches this organ, it divides into two sets of branches, some of which are distributed to the epididymis, and others enter the testicle at its upper margin, and assist in constituting its tissue. The excretory ducts in the testicle form what are called the seminiferous vessels or tubuli seminiferi. These terminate in a white cord or nucleus—situate at the upper and inner part of the organ, where the excretory duct commences—which is called corpus Highmorianum or sinus of the semi- niferous vessels. Besides these anatomical elements of the testes, there are also—1. Veins, termed spermatic, which return1 the superfluous blood to the heart. These arise in the very tissue of the organ, and form the spermatic plexus, the divisions of which collect in several branches, that pass through the abdominal ring, and unite into a single trunk, which subsequently divides again into another plexus, termed corpus pampiniforme. This has been described as peculiar to the human species, and as a diverticulum for the blood of the testicle, whose functions are intermittent. These veins ultimately terminate on the right side in the vena cava, and on the left in the renal vein. 2. Lymphatic vessels, in considerable number, the trunks of which, after having passed through the abdominal ring, open into the lumbar glands. 3. Nerves, partly furnished by the renal and mesenteric plexuses and by the great sympathetic, partly by the lumbar nerves, and which are so minute as not to be traceable as far as the tissue of the testicle. 4. An outer membrane or envelope to the whole»organ, called tunica albuginea or peritestis. This is of an opaque white colour and of an evidently fibrous and close texture; it envelopes and gives shape to the organ, and sends into the interior of the testicle numerous filiform, flattened prolongations, which constitute incom- plete septa. These form triangular spaces, filled with seminiferous vessels, which pass, with considerable regularity, towards the superior margin and corpus Highmorianum. These elements united constitute the testicle, the substance of which is soft, of a yellowish-gray colour, and divided by prolongations of the tunica albuginea, and the tunica vasculosa of Sir A. Cooper, into a number of lobes and lobules. It seems to be formed of an immensity of very delicate, tortuous filaments, interlaced and convoluted in all directions, loosely united, between which are ramifications of the spermatic arteries and veins. According to Dr. Monro, secundus,1 the seminiferous tubes of the testicle do nt>t exceed the 210th part of an inch in diameter, and when filled with mercury, the yioth part. He calculated, that the testis consists of 62,500 tubes, supposing each to be one inch long; and that if the tubes were united they would be 5208 feet four inches long. Lauth estimates their length at 1750 feet, and Krause at 1015. The tubuli seminiferi finally terminate in straight tubes, called vasa recta, which unite near the centre of the testis in a complicated arrangement, bearing the name rete testis or rete vasculosum testis: from this from 12 to 18 ducts proceed upwards and backwards to penetrate the corpus 1 Elements of the Anat. of the Human Body, by Monro (tertius), ii. 179, Edinb., 1825. 372 GENERATION. Fig. 400. Highmorianum and tunica albuginea. These ducts are called vasa efferentia. Each of them is afterwards convoluted upon itself, so as to form a conical body, called co- nns vasculosus, having its base backwards; and at its base, the tube of each cone enters the tube of which the epididymis is formed. The epididymis is the prismatic arch, B, C, Fig. 400, which rests vertically on the back of the testicle, and adheres to it by the reflection of the tunica vaginalis, so as to appear a distinct part from the body of the testis. It is enlarged at both ends;—the upper en- largement being formed by the coni vasculosi, and called globus major; the lower called globus minor. The epididymis is formed by a single convoluted tube, a fourth of a line in diameter. When the tube attains the lower end of the globus minor, it becomes less convoluted, enlarges, turns upwards, and ob- tains the name vas defe- rens. Into the angle made by the epididymis, where it terminates in the vas de- ferens, is poured the se- cretion of thj* appendix or vasculum aberrans, which closely resembles a single lobule in struc- ture. Its use is unknown. The marginal figures exhibit the arrangement of the testis and its ducts. The testes of most ani- mals, that procreate but once a year, are comparatively small during the months when they Male Organs. Left Band Fig. Testicle covered by its membranes, and seem- ing like one body. Right Hand Fig. Testicle freed from its outer coat. A. Body of testicle. B. Commencement of epididy- mis, or globus major. C Small head, or globus minor. D. Vas deferens. Fig. 401. Human Testis injected with Mercury. 1, 1. Lobules formed of seminiferous tubes. 2. Rete testis. 3. Vasa efferentia. 4. Plexuses of efferent vessels passing into the head of the epididymis 5, 5. 6. Body of epididymis. 7. Its appendix. 8. Its tail or cauda. 9. Vas deferens. GENERATIVE APPARATUS—MALE. 373 are not excited. In man, the organ before birth, or rather during the greater part of gestation, is an abdominal viscus; but, about the seventh month of fcetal existence, it gradually Fig. 402. descends through the ab- dominal ring into the scrotum, which it reaches in the eighth month by a mechanism to be de- scribed hereafter. In some cases it never de- scends, but remains in the cavity of the abdo- men, giving rise to con- siderable mental distress in many instances; and exciting the idea, that there may be a total ab- sence of the organs, or that if they exist they cannot effect the work of reproduction. The un- easiness is needless, pro- vided there be other evi- dences of virility,—the descent appearing to be by no means essential. It has been sufficiently demonstrated, that individuals, so circumstanced, are capable of pro- creation. Few opportunities have occurred for observing the condi- tion of the testes in such cases after death; but these have not exhibited any morphological defect, which could lead to the belief, that they were incapable of executing their functions. The genital organs of a gentleman, who committed suicide on account of the non- descent of the testes, are in the Museum of Guy's Hospital, London. Mr. Curling1 examined the preparation, and found the testes, both of which were within the abdomen close to the internal ring, nearly, if not quite, the natural size; and it is stated, that the ducts contained sperm. In many animals, the testicles are always internal; whilst, in some, they appear only in the scrotum during the season of amorous excitement. M. Fodere has' indeed asserted, that the crypsorchides or testicondi,—those whose testes have not descended,—are occasionally remarked for the possession of unusual prolific powers and sexual vigour.2 Dr. Marshall states, that in the examination of 10,800 re- cruits he found 5 in whom the right, and 6 in whom the left testicle 1 Art. Testicle, in Cyclopaedia of Anatomy and Physiology, Pt. xxxviii. p. 990, Feb., 1850. 2 " Ces organes paraissant tirer du bain chaud on ils se trouvent plonges plus d'ap- titude a la secretion que lorsqu'ils sont descendus au dehors dans leurs enveloppes or- dinaires!"—Traite" de Medecine Legale, i. 370, Paris, 1813. Plan of the Structure of the Testis and Epididymis. a, a. Tubuli seminiferi. a*, a*. Their anastomoses. 6. Rete testis, c. Vasa efferentia. d. d. Plexus of efferent vessels pass- ing into the head of the epididymis. e,e,f. Body of epididymis. g. Its appendix, h. Its tail or cauda. i, i. Vas deferens. 374 GENERATION. was not apparent. He met with but one instance in which both tes- ticles had not descended.1 It appears that there is a set of barbarians at the back of the Cape of Good Hope, who are generally possessed of but one testicle, or are manor chides; and Linnaeus, under the belief, that this is a natural de- fect, has made them a distinct variety of the human species. Sir John Barrow noticed the same singularity; but Dr. Good2 thinks it doubt- ful, whether, like the want of beard amongst the American savages, the destitution may not be owing to a barbarous custom of extirpation in early life. The deviation is not, however, more singular than the unusual formation of the nates and genital organs of the female in cer- tain people of those regions, to which we have referred elsewhere. The possession of a single testicle appears to be sufficient for procrea- tion. Occasionally three exist. At times, they are extremely small, but capable of executing all their functions. Mr. Wilson3 was con- sulted by a gentleman, on the point of marriage, respecting the pro- priety of his entering into that state, whose penis and testicles very little exceeded in size those of a youth of eight years of age. He was twenty-six years old, but had never experienced sexual desire until he became acquainted with the lady whom he proposed to make his wife; after which he had repeated erections, with nocturnal emissions. He married; became the father of a family; and when twenty-eight years old the organs had increased to the usual size of those of the adult. In certain cases, the testes are drawn up against the abdominal ring so as to encourage the idea, that there are none in the scrotum. Pro- fessor Gross4 has given the cases of two boys, one fourteen, the other eleven years of age, who were said to have been castrated; and a medical practitioner deposed to the absence of the testes; which, how- ever, were found in the groin, a little below the external ring, whence, by a little traction, they could be easily drawn down into the scrotum. The testicle is connected with the abdominal ring by means of the spermatic cord, a fasciculus of about half an inch in diameter, which can be readily felt through the skin of the scrotum. It is formed essen- tially of the vessels and nerves that pass to or from the testicles;— the spermatic artery, spermatic veins, lymphatics, and nerves of the organ, and the vas deferens, or excretory duct. These are bound to- gether by means of areolar tissue; and, externally, a membranous sheath of a fibrous character envelopes the cord, and keeps it distinct from the surrounding parts, and especially from the scrotum. When the cord has passed through the abdominal ring, its various elements are no longer held together, but each passes to its special destination. The scrotum or purse is a continuation of the skin of the inner side of the thighs, perineum, and penis. It is symmetrical, the two halves being separated by a median line or raphe. The skin is of a darker colour here than elsewhere; rugous; studded with follicles, and spar- ingly furnished with hair. This may be considered its outermost coat. 1 Hints to Young Medical Officers in the Army, p. 83. 2 Physiological Proem to class Genetica, Study of Medicine, vol iv. 8 Lectures on the Structure and Physiology of the Male Urinary and Genital Organs, &c, London, 1821. * Western Journal of Medicine and Surgery, May, 1841, p. 355. GENERATIVE APPARATUS—MALE. 375 Beneath this is the dartos,—a reddish, areolar membrane, which forms a distinct sac for each testicle; and a septum—septum scroti—between them. Much discussion has taken place regarding the nature of the dartos; some supposing it to be muscular, others areolar. Breschet and Lobstein affirm, that it does not exist in the scrotum before the descent of the testes, and, with more recent anatomists, they consider it to be formed by the expansion of the gubernaculum testis. ' Meckel, however, suggests, that it constitutes the transition between the areolar and muscular tissues, and that there exists between it and other mus- cles the same relation as between the muscles of the superior and infe- rior animals. It consists of long fibres considerably matted together, and passing in every direction, but which are easily separable by dis- tension with air or water, and by slight maceration. The generality of anatomists conceive it to be of an areolar character, yet it is manifestly contractile; corrugates the scrotum, and doubtless consists of muscular tissue also; Professor Horner,1 indeed, affirms, that he dissected a sub- ject in January, 1830, in which the fibres were evidently muscular, although interwoven. Beneath the dartos a third coat exists, which is muscular:—it is called cremaster or tunica erythroides; arises from the lesser oblique muscle of the abdomen; passes through the abdominal ring; aids in the formation of the spermatic cord, and terminates insen- sibly on the inner surface of the scrotum. It draws the testicle up- wards. The areolar substance, that connects the dartos and cremaster with the tunica vaginalis, has been considered by some as an additional coat, and termed tunica vaginalis communis. The tunica vaginalis or tunica elytrdides, is a serous membrane, enveloping the testicle and lining the scrotum ; having, consequently, a scrotal and a testicular portion. We shall see, hereafter, that it is a dependence of the peritoneum, pass- ing before the testicle in its descent, and afterwards becoming separated from any direct communication with the abdomen. The vas deferens or excretory duct of the testicle commences at the globus minor of the epididymis, (C, Fig. 400,) itself formed of a convoluted tube. This, when unfolded, according to Monro, measures thirty-two feet. As soon as the vas deferens quits the testicle, it joins the spermatic cord; passes upwards to the abdominal ring; separates from the bloodvessels on entering the abdomen, and descends downwards and inwards to the posterior and inferior part of the bladder, passing between the basfond of the latter and the ureter. It then con verges towards its fellow along the under extremity of the bladder, at the inner margin of the vesicula seminalis of the same side, and ultimately opens into the urethra near the neck of the bladder, At the base of the prostate, it receives a canal from the vesicula, and continues its course to the urethra under the name of ejaculatory duct. The vas deferens has two coats, the outer of which is very firm and almost cartilaginous; but its structure is not manifest; the inner thin, and belonging to the class of mucous mem- branes. The vesiculce seminales, Fig. 403, 4, 4, are considered to be two convoluted tubes,—one on each side,—which are two inches or two inches and a half long, and six or seven lines broad at the fun- dus, and are situate at the lower fundus of the bladder, between it and the rectum, and behind the prostate gland. At the anterior extremi- 1 Special Anat. and Histology, 7th edit., ii. 116, Philad., 1846. 376 GENERATION. Vertical Section of the Union of Vas Deferens and Vesiculae Seminales so as to show their Cavities. 1, 1. Vas deferens with thick parietes and narrow cavity. 2, 2. Portion of the same where the cavity is enlarged. 3, 3. Extre- mities of vas deferens from each side where they join the vesicula seminales and ductus ejaculatorius. 4, 4. Vesical* seminales distended with air and dried. 5,5. Arteries to the vesiculae. 6. Portion of the perito- neum covering the posterior part of the vesi- culae. 7. Ejaculatory ducts. FiS-403- ties they approach each other very closely, being separated only by the vasa deferentia. When inflated and dried, they present the appearance of cells; but are generally conceived to be tubes, which, being convoluted, are brought within the compass of the vesicula). When dissected and stretched out, they are four or five inches long by about one-fourth of an inch in diameter. M. Amussat,1 however, denies this arrange- ment of the vesieulae, and affirms, that he has discovered them to be formed of a minute canal of considerable length, variously convoluted, the folds of which are united to each other by cellular fila- ments, like those of the spermatic vessels. At the anterior part, termed the neck, a short canal passes off, which unites at an acute angle with the vas deferens, to form the ductus ejaculatorius. Between the openings of the ejaculatory ducts at the lateral and anterior part of the verumontanum, there is often a de- pression, sometimes of a large size, which is termed utriculus, vesica seu vesicula prostatica and sinus pocularis, and has been regarded as the analogue to the uterus in the female.2 The vesiculae are formed of two membranes; the more external like that of the vas deferens, and capable of contracting in the act of ejaculation; and an internal mucous lining, of a white, delicate character, a little like that which lines the interior of the gall-bladder. The vesiculae are manifestly cdntractile, owing to unstriped muscular fibres in their second coat. They are filled, in the dead body, with an opaque, thick, yellowish fluid, very different in appearance from the sperm ejaculated during life.3 The prostate gland is an organ of very dense tissue, embracing the neck of the bladder, and penetrated by the urethra, which traverses it much nearer its upper than lower surface. The base is directed back- wards ; the point forwards, and its inferior surface rests upon the rectum, so that, bypassing the finger into the rectum, enlargements of the organ may be detected. The prostate was once universally es- teemed glandular, and is still so termed; but it is generally and cor- rectly regarded as an agglomeration of several small follicles, filled by a viscid whitish fluid. These follicles have numerous minute excre- tory ducts, which open on each side of the caput gallinaginis. The glands of Cowper are two small, oblong bodies; of the size of a pea; of a reddish colour, and somewhat firm tissue. They are situate anterior to the prostate; parallel to each other, and at the sides of the urethra. Each has an excretory duct, which creeps obliquely in the spongy tissue of the bulb, and opens before the verumontanum. 1 Magendie, Precis, &c, ii. 514. 2 E. H. Weber, Muller's Archiv., S. 421, Jihrgang, 1843; and Rud. Leuckart, art. Vesicula Prostatica, in Cyclop, of Anat. and Physiol., iv. 1415, Lond., 1852. 3 S. R. Pittard, Art. Vesiculse Seminales, Ibid., iv. 1429. GENERATIVE APPARATUS—MALE. 377 The male organ or penis consists of the corpora cavernosa and corpus spongiosum; parts essentially formed of an erectile tissue, and sur- rounded by a very firm elastic covering, which prevents over-disten- sion, and gives form to the organ. The corpora cavernosa constitute the great body of the penis. They are two tubes, which are united and separated by an imperfect partition. Within them a kind of cellular tissue exists, into which blood is poured, so as to cause erection. The posterior extremities of these cavernous tubes are called crura penis. These separate in the perineum, each taking hold of the ramus of the pubis; and, at the other extremity, the cavernous bodies terminate in rounded points under the glans penis. The anatomical elements of the internal tissue of the corpora cavernosa are,—ramifications of the cavernous artery, which proceeds from the internal pudic; those of a vein bearing the same name; and probably, nerves,—although they have not been traced so far. All these elements are supported by fila- mentous prolongations from the outer dense envelope. A difference of opinion prevails amongst anatomists with regard to the precise arrange- ment of these prolongations. Some consider them to form cells, or a kind of spongy structure, on the plates of which the ramifications of the cavernous artery and vein and of the nerves terminate, and into which the blood is extravasated. Others conceive, that the internal arrangement consists of a plexus of minute arteries and veins, sup- ported by the plates of the outer membrane, interlacing like the capil- lary vessels, but with this addition, that in place of the minute veins becoming capillary in the plexus, they are of greater size, forming very extensible dilatations and net-works, and anastomosing freely with each other. If the cavernous artery be injected, the matter^rst fills the ramifications of the artery, then the venous plexuses of the cavern- ous bodies, and ultimately returns by the cavernous vein, having pro- duced erection. The same effect is caused still more readily by inject- ing the cavernous vein. Professor J. Miiller, who has investigated the structure of the male organ, discovered two sets of arteries in the organ, differing from each other in size, mode of termination, and uses: the first Fig. 404. he calls rami nutritii, which are distributed upon the parietes of the veins and through- out the spongy 'substance, differing in no respect from the nutritive arteries of other parts. The second set he calls arterice heli- They differ from the nutritive ves- cinai. sels in form, size, and distribution. They are short, and are given off from the larger branches, as well as from the finest twigs of the artery; most of them come off at a right angle, and project into the cavity of the spongy substance, either terminating abruptly or swelling out into a clublike process without again subdividing. Almost all these arteries have this character, that they are bent like a horn, so that the end describes half a circle or somewhat more. Section of the Penis. A. External membrane or sheath of penis. B. Corpus caveruosum. D. Corpus spongiosum urethras. 378 GENERATION. Fig. 405. These arteries have a great resemblance to the tendrils of the vine, whence their name—arterioz helicince. A minute examination of them, either with the lens or with the microscope, shows, that, although they at all times project into the venous cavities of the corpora cavernosa, as in the subjoined figures, they are not entirely naked, but are covered by a delicate mem- brane, which under the microscope appears granu- lar. The views of Miiller are embraced by Erdl, Krause, and Hyrtl,1 but the researches of Valentin' and Berres, of Sappey, J. Beclard, Ch. Robin and Segond,3 are not in accordance with them. The result of numerous examinations has convinced the former, that the helicine arteries are not peculiar vessels, but merely minute fibres that have been of gians/ 6. Prominences divided or torn; and that the real distribution of of glans on each side of. i r> ii fraenum. 7. Furrow which the vessels of the corpora cavernosa follows in every gianflc^ollliandL6 respect the most simple laws. Gerlach and Kolli- ker regard them as true vascular formations not produced artificially. They consider them not to be cascal at their extremities, except in rare Glans Penis injected. 1,1. Portions of corpora cavernosa. 2. Prepuce turned back. 3. Its frae- num. 4, 4. Glandulae odo- riferae Tysoni. 5. Point Fig. 406. instances.4 Kolliker5 states, that *he has observed them giving off minute vessels, which, like the other arterial prolongations, are continued further, and terminate in the venous spaces. The investigations of Miil- ler led him to infer, that, both in man and the horse, the nerves of the corpora cavernosa are made up of branches proceeding from the organic as well as the ani- Fig. 407. Portion of the Erectile Tissue of the Corpus Caverno- sum magnified, to show the areolar structure and the distribution of the arteries. a. A small artery, supported by the larger trabecule, and branching out on all sides, e. The tendril-like arterial _ .. . . tufts, or helicine arteries of MUller. d. The areolar structure A single Tuft or Helicine Artery pro- formed by the finer trabecule. jecting into a Vein highly magnified. 1 Lehrbuch der Anatomie des Menschen, S. 505, Prag., 1846. 2 Muller's Archiv. fiir Anatomie, u. s. w., cited in Lond. Med. Gazette, June 23.1838, p. 543 ; and Valentin, Lehrbuch der Physiologie des Menschen, ii. 843, Braunschweig, 1844. 3 Traite d'Anatomie Generale, p. 314, Paris, 1854. 4 J. W. Ogle, Report of Micrology, Brit, and For. Med. Chir.-Rev., Oct., 1855, p. 515. 5 Mikroskopische Anatomie, ii. 412, Leipz., 1854, and Amer. edit, of Sydenham So- ciety's edit, of his Human Histology, p. 632, Philad., 1854. GENERATIVE APPARATUS—MALE. 379 mal system, whilst the nerves of animal life alone furnish the nerves of sensation of the penis. Attached to the corpora cavernosa, and running in the groove be- neath them, is a spongy body of similar structure,—corpus spongiosum urethroz,—through which the urethra passes. It commences, poste- riorly, at the bulb of the urethra,—already described under the Secre- tion of Urine,—and terminates anteriorly in the glans, which is, in no wise, a dependency of the corpora cavernosa, but is separated from them by a portion of their outer membranes; so that erection may take place in the one, and not simultaneously in the other; and in- jections into the corpora cavernosa of the one do not pass into those of the other. The glans appears to be the final expansion of the erectile tissue which surrounds the urethra. The posterior circular margin of the glans is called corona glandis, and behind this is a de- pression termed cervix, collum or neck. Several follicles exist here, called glandulce odoriferce Tysoni: these have always been considered to secrete an unctuous humour called smegma prcepvtii, which often accumulates largely, where cleanliness is not attended to. The little white elevations that are found around the corona glandis have been generally regarded as Tyson's glands. They have, however, been examined by Dr. G-. Simon,1 who affirms, that they are nothing more than small round elevations of cutis, covered by papillae and epithe- lium. They consist of fibro-areolar tissue, like that of the rest of the cutis; and the papillae on them have no peculiar characters. The sole function which he ascribes to them is that of increasing the sensibility of the glans. The only organs, which Dr. Simon could find for the special secretion of the smegma—and these are not constant—are whitish corpuscles lying in or beneath the cutis, which, with the mi- croscope, appear as small roundish sacculi, closed below, opening by a narrow orifice on the surface, and containing a white substance. These are usually situate on or behind the corona glandis, in front of or near the fraenum, and sometimes on the anterior surface of the glans. Two or three may be found, and, in a few cases, as many as six. The penis is covered by the skin, which forms, towards the glans, the prepuce or foreskin. The areolar tissue which unites it to the organ is lax, and never contains fat. The inner lamina of the prepuce being inserted circularly into the penis, some distance back from the point, the glans can generally be denuded, when the prepuce is drawn back. The under and middle part of the prepuce is attached to the extremity of the glans by a duplicature, called frcemim prceputii, which extends to the orifice of the urethra. The skin is continued over the glans, but it is greatly modified in its structure, being smooth and velvety, highly delicate, sensible, and vascular. Lastly.—In addition to the accelerators urince, transversus perinei, sphincter ani, and levator ani muscles, which we have described as equally concerned in the excretion of urine and semen, the erector penis or ischio-cavernosus muscle is largely connected with the function of 1 Muller's Archiv., 1844, Heft 1, cited in Brit, and For. Med. Rev., April, 1845, p. 567. 380 GENERATION. generation. (See Fig. 181.) The genital organs of man are, in reality, merely an apparatus for a glandular secretion, of which the testicle is the gland; the vesiculae seminales are supposed to be the reservoirs ■ and the vas deferens and urethra the excretory ducts;—the arrange- ment which we observe in the penis being for the purpose of convey- ing the secreted fluid into the parts of the female.1 1. SPEHM. The sperm is secreted by the testicles from the blood of the sperma- tic artery, by a mechanism, which is no more understood than that of secretion in general. When formed, it is received into the tubuli seminiferi, and passes along them to the epididymis, vas deferens, and vesiculae seminales, where it is generally conceived to be deposited, until under venereal excitement it is projected into the urethra. That this is its course is sufficiently evidenced by the arrangement of the excretory ducts, and by the function which it has to fulfil. De Graaf,2 however, adduces an additional proof. On tying the vas deferens of a dog, the testicle became swollen under excitement, and ultimately the duct gave way between the testicle and ligature. The causes of the progression of the sperm through the ducts are,—the continuity of the secretion by the testicle, and the contraction of the excretory ducts themselves. These are the efficient agencies. It has been a question with physiologists, whether the secretion of the sperm be constantly taking place—or whether, as the function of generation is accomplished at uncertain intervals, the secretion may not likewise be intermittent. It is impossible to arrive at any positive conclusion on this point. It would seem, however, unnecessary for the secretion to be effected at all times; and it is more probable, that when the vesiculae seminales are emptied of their contents during coition, a stimulus is given to the testes by the excitement, and they are soon replenished. This, however, becomes more and more difli- cult in proportion to the number of repetitions of the venereal act, as the secretion takes place at best but slowly. By some, the spermatic and pampiniform plexuses have been regarded as diverticula to the testes during this intermission of action. The sperm passes slowly along the excretory ducts of the testicle, owing partly to the slowness of the secretion, and partly to the arrangement of the ducts, which, as we have seen, are remarkably convoluted, long, and minute. The use of the vesiculae seminales has been disputed. The majority of physiologists consider them to be reservoirs for the sperm, and to serve the same purpose as the gall-bladder in the case of the bile. Others, however, have supposed, that they secrete a fluid of a peculiar nature, the use of which may probably be to dilute the sperm; whilst others, again, infer, that they are both seminal reservoirs, and secreting organs,—furnishing mucus, or some other fluid, for admixture with the semen. Dr. John Davy3 found spermatozoids in the fluid of the 1 See Kobelt, De l'Appareil du Sens Genital des deux Sexes, traduit de l'Allemand, par H. Kaula, D. M. Paris, 1851. 2 De Virorum Organ. Gener. inserv., in Med. Oper. Omn., Amstel., 1705. 8 Edinb. Med. and Surg. Journ. for July, 1838, p. 12; and Researches, Physiological and Anatomical, Amer. Med. Libr. edit., p. 3G3, Philad., 1840. GENERATIVE APPARATUS—MALE—SPERM. 381 vesiculae; but except in two instances none could be seen in that ex- pressed from the divided substance of the testes. He invariably observed, however, extremely minute, dense spherules, which he con- jectured to be ova of spermatozoids.1 The vesiculae are manifestly not essential to the function of generation, as they do not exist in all animals; and in several animals in which they do, there is no direct communication between the duct and the vas deferens, which open separately into the urethra. This circumstance, however, with the fact, that they generally contain, after death, a fluid of different ap- pearance and properties from those of the sperm,—with the glandular structure, which their coats seem in many instances to possess,—is opposed to the view, that they are simple reservoirs for semen, and favours that which ascribes to them a peculiar secretion. Where this communication between the duct of the vesiculas and the vas deferens exists, a reflux of the semen and an admixture between the sperm and the fluid secreted by them may take place. It is not improbable, how- ever, as M. Adelon2 suggests, that all the excretory ducts of the tes- ticle may act as a reservoir; and in the case of animals, in which the vesicula? are wanting, they must possess this office exclusively. If we are to adopt the description of M. Amussat as an anatomical fact, the vesiculae themselves are constituted of a convoluted tube, having an arrangement somewhat resembling that which prevails in the excretory ducts of the testes.3 That these excretory ducts may serve as reservoirs is proved by the fact, that impregnation is practicable after thorough castration. This has been doubted both as regards animals and man, but there is no question of the fact as respects the former. Dr. Pue, of Baltimore, related to the author unquestionable instances of the kind. In one case, a boar was observed on one side of a hedge striving to get at some sows in heat on the other side. The boar was castrated, and no inconvenience being apprehended, he was turned loose into the field with the sows. In five minutes after the operation, he had intercourse with one of them, and subsequently with others. The first sow brought forth a litter, but none of the others were impregnated. In another case, after a horse had been castrated, it was recollected, that the male organ had not been washed—which, it seems, is looked upon as ad- visable. To save inconvenience, it was suggested, that the same effect might be produced by putting him to a mare, then in the stable, and in heat. This was done, and, in due time, the mare brought forth a foal, unequivocally the result of this sexual union. Mr. Walton Ha- milton,—a great breeder of horses, in Saratoga county, New York,— informed the author's friend, Mr. Nicholas P. Trist, that he, also, had known several instances of impregnation after castration.4 It is to be presumed, that the power of procreation can exist for a short time only after the operation; yet a secretion may take place from the lining membrane of the ducts, and vesiculae, and from the 1 Researches, Physiological and Anatomical, Amer. Med. Libr. edit., p. 373, Philad., J Physiologie de l'Homme, 2de e"dit., iv. 15, Paris, 1829. 3 Magendie, Precis, &c, ii. 348. * See some remarks, by the author, in American Medical Intelligencer, p. 146, July 15, 1S37 ; and by Dr. Warrington, Ibid., p. 244, Oct. 1. 382 GENERATION. prostate and other follicles; but this secretion cannot supply the place of sperm. Sir A. Cooper gives the case of a man, who stated to him that for nearly the first twelve months after complete castration, he had emissions in coitu, or the sensation of emissions. Afterwards he had erections and intercourse at distant intervals, but without the sen- sation of emission.1 It has been asked, how it happens, that the sperm, in its progress along the vas deferens, does not pass directly on into the urethra by the ejaculatory duct, instead of reflowing into the spermatic vesicles where these exist ? This, it has been imagined, is owing to the exist- ence of an arrangement at the opening of the ejaculatory duct into the urethra, similar to that which prevails at the termination of the chole- doch duct in the duodenum. It is affirmed by some, that the prostate exerts a pressure on the ductus ejaculatorius, and that the opening of the duct into the urethra is smaller than any other part of it; by others, that the ejaculatory ducts are embraced, along with the neck of the bladder, by the levator ani, and consequently, that the sperm finds a readier access into the ducts of the vesiculae. Sperm—sperma, semen, lac maris, male's milk, propagatory or genital liquor, vitale virus, vital or quickening venom—is of a white colour, and of a faint smell, which, owing to its peculiar character, has been termed spermatic. This smell would seem to be derived from the secretions of the vesiculae seminales, prostate, and mucous follicles of the urethra, as pure semen taken from the epididymis or vas deferens does not possess it. It is of viscid consistence, a saline, irritating taste, and appears com- posed of two parts, the one more liquid and transparent, and the other' more grumous. In a short time after emission, these two parts unite, and the whole becomes more fluid. When examined chemically, sperm appears to be of an alkaline and albuminous character. M. Vauquelin2 analyzed it, and found it to be composed,—in 1000 parts,—of water, 900; animal mucilage, 60; soda, 10; calcareous phosphate, 30. John's analysis3 accords with this. Berzelius affirms, that it contains the same salts as the blood, along with a peculiar animal matter—spermatin. After citing these analyses, M. Easpail4 observes, that if any thing be capable of humiliating the pride of the chemist, it is assuredly the iden- tity he is condemned to discover amongst substances, which fulfil such different functions. Of late, the sperm of the carp, the cock, and the rabbit has been subjected to repeated and careful analysis by Professor Frerichs of Gottingen; and the following are the published results. First. The pure semen presents the appearance of a milky fluid, of a mucous consistence and neutral reaction. A slight alkaline reaction was perceived only once. Secondly. The developed spermatozoids con- sist of binoxide of protein; the same substance, which Mulder has proved to be the principal constituent of the epithelia, as well as of the horny tissues in general. Thirdly. The spermatozoids contain about 4 per cent, of a butter-like fat, as well as phosphorus in an unoxidized 1 Observations on the Structure and Diseases of the Testis, Lond., 1830. 2 Annales de Chimie, ix. 64. 3 Chemische Tabellen des Thierreichs, S. 169, Nurnberg, 1814; cited in Burdach'a Physiologie, u. s. w., S. 111. * Chimie Organique, p. 386, Paris, 1833. GENERATIVE APPARATUS—MALE—SPERM. 383 state and about 5 per cent, of phosphate of lime. Fourthly. The fluid part is a thin solution of mucus, which, in addition to the animal matter, contains chloride of sodium and small quantities of phosphate and sul- phate of the alkalies. Fifthly. The imperfectly developed spermatozoids are composed of an albuminous substance, the quantity of which dimi- nishes in proportion to the progress of the morphological developement. Sixthly. The perfectly developed semen contains no longer any albu- minous compound; and Seventhly. The semen in fishes, birds, and the mammalia possesses, essentially, the same chemical composition. The most important inference deducible from these statements com- municated by Professor Frerichs to Messrs. Wagner and Leuckardt,1 is, according to these gentlemen, the fact, that the spermatozoids, in their chemical constitution, belong to the same category as the epithe- lial cells of the animal body, which, they think, removes every doubt respecting the nature of these formations,—every idea, that is, of their being independent animals. That they are not so appears to the author most probable, but not for the chemical reasons given by these gentle- men, whose conclusion can scarcely, indeed, be regarded in any other light than as a non sequitur. No analysis has been made of the sperm as secreted by the testicle. The fluid examined has been the compound of it and the secretions of the prostate gland and those of Cowper. The thicker, whitish portion is considered to be the secretion of the testicles;—the more liquid and transparent, the fluids of the accessory glands or follicles. Some authors have imagined, that a sort of halitus or aura is given off from the sperm, which they have called aura seminis, and have considered to be suffi- cient for fecundation. The fal- lacy of this view will be exhi- bited hereafter. By the microscope, nume- rous minute bodies, already referred to, are seen in the sperm, termed seminal animal- cules, spermatozoa, zoospermes, spermatozoids or seminal or spermatic filaments — which have generally been con- ceived important agents in generation. By careful exa- mination, Wagner2 discovered other minute, round, granu- Spermatozoa from Man, and their developement. A. Spermatozoa from the semen of the vas deferens. 1 to 4. Show their variety of character. 5. Seminal granules.— b. Contents of the semen of the testis. 1. Large round cor- i,i,j. i-i ' ~i L puscle or cell. 2. A cell containing three roundish granu- lated. DOdieS WhlCh may almost lar hodies, from which the spermatozoa are developed. 3. \\a r\ptPCtP(\ • llld ATP A f?sci?ul,Js of spermatozoa, as they are seen grouped to- gether in the testis. always much less numerous than the spermatozoids. These bodies he distinguishes by the name seminal 1 Art. Semen, Cyclop, of Anat. and Physiol., Pt. xxxiv. p. 506, January, 1849; and art. Zeugung, in Wagner's Handworterbuch der Physiologie, iv. 849, Braunschw., 1853. 2 Elements of Physiology, translated from the German, by Robert Willis, M. D., pt. i. p. 4, Lond., 1841; see, also, Mandl, Manuel d'Anatomie Grenerale, p. 494, Paris, 1843. 384 GENERATION. granules, granula seminis. Both elements of the sperm are suspended in a small quantity of fluid perfectly homogeneous, transparent, and clear as water. "Pure semen, therefore, in its most perfect state, con- sists principally of seminal animalcules and seminal granules, both of which are enveloped in a small quantity of fluid." This fluid Wagner called liquor seminis; and he suggested,1 in connexion with the disco- veries of Schwann and Schleiden, (referred to at page 463-of the first volume,) whether, in the developement of the spermatozoids, the liquor seminis may not be regarded as a matrix (Zellenkeimstoff, cyto- blastema, Schwann), in which the granular nuclei are developed as cyto- blasts, which again put forth their covering or cyst as a cellular wall. The finely granular contents would then have to be considered as the cell-fluid. The cytoblasts disappear as soon as the spermatozoids are evolved in their contents; and Fig. 409. the cells burst and cast out the c D fancied animalcules, as the cells of the algae scatter abroad their sporules. More recently, Wag- ner, in conjunction with Leuck- ardt, has published the results of his farther observations and of those of others on this matter. Among the mammalia, they af- firm, the developement of sperm- atozoids takes place in the inte- Developing Vesicles of Spermatozoids from the ^OT of Vesicle-shaped globules, Testicle of the Dog. which fill up the minute ducts of the testicles in great quantity. Fig- 41°- Most of these vesicles, " vesicles A b c d of evolution," are free within the ducts, as represented in the mar- ginal figures, A, B, c, Fig. 409; and are frequently surrounded by a membrane, either singly, as in D, or in numbers of from three to seven, E ; and, according to Spermatozoid of the Dog in the Interior of the ^Uiker, °™ Cyst may Contain Vesicle of Developement. as many as twenty. All these cells of evolution or develope- ment are formed within other cells; and it is often difficult to deter- mine, whether an individual cell or vesicle is destined for the produc- tion of other cells—daughter cells—or immediately for the formation of a spermatozoid. Wherever free vesicles of developement are found, they have—in the opinion of Wagner and Leuckardt2—been produced in the interior of other cellular formations, and have been set free by their dissolution. Each spermatozoid would seem to be produced in a separate cyst, and where many of these are seen in one cyst, it is owing to the different vesicles having burst and discharged their spermatozoids into the external cyst. The number of enclosed sperm- 1 Op. cit., p. 27. 2 Op. cit., p. 477. GENERATIVE APPARATUS—MALE—SPERM. 385 atozoids will thus be an index of the number of vesicles of develope- ment. A, B, c, D, Fig. 410, exhibit the mode in which the spermatozoid lies in the vesicle of developement; and in which it is occasionally seen projecting from it. Great difference of sentiment has existed in regard to the nature of those bodies. M. Virey1 conceives, that as the pollen of vegetables is a collection of small capsules, containing within them the true fecun- dating principle, which is of extreme subtilty, the pretended spermatic animalcules are tubes containing the true sperm, and the motion we observe in them is owing to the rupture of the tubes; whilst M! Kas- pail2 is led to think, that they are mere shreds, (lambeaux,) of the tissues of the generative organs, ejaculated with the sperm, which describe involuntary movements by virtue of the property they pos- sess of aspiring and expiring. In confirmation of this view, he states, that if we open an ovary of the mussel, we may observe alongside the large ovules myriads of moving shreds, whose form and size are infinitely varied, and which possess nothing resembling regular organ- ization. They bear evident marks of laceration. These shreds, he conceives, may affect greater regularity in certain classes of animals of a more elevated order; but he concludes, that howsoever this may be, the spermatic animalcules, which have hitherto beeti classed amongst those incertce sedis, may be provisionally placed in the genus cercaria,— that is, amongst infusory, agastric animals having a kind of tail,— which M. Easpail considers the simplest of animated beings, and to live only by " aspiration and expiration." Wagner also remarks, that the expression cercaria seminis, applied to spermatozoids, can only be a collective title, and that the manifold forms of spermatozoids, which he has found in the seminal fluid of a great number of animals, must be viewed in the light of so many different species. Ehrenberg refers them to the haustellate entozoa. The author has repeatedly examined the sperm with microscopes of high magnifying power, but without being able to satisfy himself, that the minute caudate bodies, contained in it, are animalcular. Sir Everard Home3 and Mr. Bauer were equally unsuccessful, and they were led to conclude, that the appearance of living animalcules in the semen is not real, but the effect of a microscopic deception. Wagner4 formerly considered, that they are essential elements of the seminal fluid, and bear a specific relation to the generative act, and that they are thus far comparable to the blood-globules, which present them- selves in the same manner, as essential typically organized constituents of the blood amid the liquor sanguinis, just as the spermatozoids pre- sent themselves amid the liquor seminis. The question of the ani- mality of these spermatozoids he considered to be undetermined, as their internal organization had not been detected. In the appendix, however, to the translation of his work, Dr. Willis5 remarks, that in the examination of the spermatozoids of the bear, Valentin6 had set- 1 Art. Generation, in Diet, des Sciences Medicales ; and Philosophie d'Histoire Na- turelle, Paris, 1835. 2 Op. citat., p. 389. 3 Lect. on Comp. Anat., v. 337, Lond., 1828. 4 Op. citat., p. 34. 6 Ibid., p. 228. 6 Nov. Act. Acad. C. L. Natur. Curios., vol. xi. 1839. VOL. II.—25 386 GENERATION. tied the question of the organization, and consequently true animal nature, of the seminal animalcule; but the matter was not determined by this statement, nor by the categorical declaration of M. Pouchet ■ that " every mode of investigation presented to the human mind ap. pears to speak in favour of the animality of the spermatozoids. In- ward feeling (le sens interne), observation, experiment, and reflection unite in expressing, that they can be nothing else than animals." On the other hand, M. Donne,2 like M. Kaspail, regards them as resulting from a kind of desquamation of the parietes of the seminiferous tubes* whilst Carpenter,3 Dujardin,4 and others consider, that there is little reason to regard them as independent animalcules. The former esteems them to be bodies having an inherent power of motion, not exceeding in their activity ciliated epithelium cells, and even blood corpuscles* and he thinks there is no evidence, that their function is any higher than that of the pollen-tube of plants, which conveys into the ovulum the germ of the first cells of the embryo. The whole of this subject has been since re-examined by Wagner in connexion with Leuck- ardt; and in an able view by these gentlemen,5 of the morphology and developement of the spermatozoids, we have the following remarks:— '; At the period when the spermatozoa were still considered as indi- vidual animated creatures, it was natural, that those qualities should be sought for, which distinguish animals generally; and it was fre- quently asserted, that the distinct traces of an internal organization had been found in them. Even Leeuwenhoek,6 the oldest observer of these structures, describes in the body of the spermatozoa of the ram and of the rabbit indications, which were subsequently interpreted by Ehrenberg7 and Valentin8 to be intestines, stomachic vesicles, and even generative organs. Other histologists,—for instance, Schwann and Henle,—thought themselves justified in calling a dark spot, which shows itself occasionally on the body of the spermatozoon in man, but which is decidedly a mere accidental formation, as a suctorial cavity. But all these statements are now no longer believed in, as our present knowledge of the developement of these formations has entirely re- moved the idea of their parasitic nature. Indeed, the subject requires no further refutation, as an unprejudiced observation proves that the spermatozoa are everywhere void of a special organization, and con- sist of a uniform homogeneous substance, which exhibits, when exa- mined by the microscope, a yellow amber-like glitter. The above- mentioned investigators have by this time undoubtedly seen their error." The view, that they are reproductive particles, but not animalcules, appears to the author to be the most in accordance with the pheno- mena. 1 Theorie Positive de POvulation Spontanee, et de la Fecondation, &c, p. 363, Paris, 1847. * Cours de Microscopie, p. 176, Paris, 1844. 3 Human Physiology, § 733, Lond., 1842 ; also, Amer. edit., p. 750, Philad., 1855. 4 Annates des Sciences Natur. Zoologie, viii. 291; and Manuel de l'Observateur au Microscope, p. 96, Paris, 1843. 4 Art. Semen, in Cyclop, of Anat. and Physiology, part xxxiv. p. 502, Jan., 1849. 6 Opera, iv. 168, 284. * Infusoriensthierchen, S. 465. 8 Nov. Act. Acad. Leopold, xix. 239. GENERATIVE APPARATUS—FEMALE. 387 The presence of spermatozoids, whole or broken in fragments, may aid in detecting nocturnal emissions, and be of assistance in cases of alleged rape. It would seem, however, that they are not found solely in the sperm: for Mr. Liston and Mr. Lloyd,1 of St. Bartholomew's Hospital, London, stated to the Medico-Chirurgical Society, that in cases of common hydrocele, in which they examined microscopically the fluid withdrawn by tapping, they found a great number of them. Mr. Lloyd counted forty in one drop. Some were observed to retain their power of motion for three hours after the fluid had been with- drawn. In the fluid of many other cases of hydrocele, he was unable to detect them. Since these remarks were made, however, by Mr. Lloyd, they have been observed repeatedly in the fluid of common hydrocele of the tunica vaginalis testis, and in encysted hydroceles.2 This may be owing to the rupture of a seminal duct; but Mr. Paget3 considers, that the most probable explanation of their occurrence in the fluid of cysts connected with the testicle seems to be, that certain cysts, seated near the organ which naturally secretes the materials for semen, may possess the power of forming a similar fluid. It must be borne in mind, however, as before remarked, that bodies resembling spermatozoids were found by M. Donne in the nasal mucus. The agency of the sperm in fecundation will be considered here- after. The sperm being the great vivifying agent,—the medium by which life is communicated from generation to generation,—it has been looked upon as one of the most—if not the most—important of animal fluids; and hence it is regarded, by some physiologists, as formed of the most animalized materials, or of those that constitute the most elevated part of the new being—the nervous system. The quantity of sperm se- creted cannot be estimated. It varies according to the individual, and to his extent of voluptuous excitement, as well as to the degree of previous indulgence in venereal pleasures. Where the demand is frequent, the supply is larger; although when the act is repeatedly performed, the absolute quantity at each copulation may be less.4 b. Genital Organs of the Female. The genital organs of the male effect fewer functions than those of the female. They are inservient to copulation and fecundation only. Those of the female,—in addition to parts, which fulfil these offices,— comprise others for gestation and lactation. The soft and prominent covering to the symphysis pubis—which is formed by the common integument, elevated by fat, and, at the age of puberty, covered by hair, formerly termed tressoria—is called mons 1 Provincial Medical Journal, cited in Medical Examiner, July 22,1843, p. 168. 2 Medico-Chirurgical Transactions, vol. xxvii., Art. 25, London, 1844; Dr. R. L. Macdonnell, British American Journal of Medicine, Montreal, 1849; and Mr. Curling, Edinb. Monthly Journal of Med. Science, May, 1843; and Art. Testicle, in Cyclop, of Anat. and Physiol., Pt. xxxviii. p. 998, Feb. 1850. 5 Brit, and For. Med. Rev., January, 1844, p. 270. 4 Theophrastus, Pliny, and Athenseus assert, that with the help of a certain herb, an Indian prince was able to copulate seventy times in twenty-four hours!—Theophr. 1. c. v., Plin. 1. xxvi. c. 9, and Athemeus, 1. i. c. 12. See, also, Art. Cas rares, in Diet. des Sciences Medicales. 388 GENERATION. veneris. The absence of this hair has, by the vulgar, been esteemed a matter of reproach; and it was formerly the custom, when a female had been detected a third time in incontinent practices, in the vicinitv of the Superior Courts of Westminster, to punish the offence by cut- ting off the tressoria1 in open court. Occasionally its growth is ex- cessive. Below this are the labia pudendi or labia majora, which are two large, soft lips, formed by a duplicature of the common integu- ment, with adipose matter interposed. The inner surface is smooth and studded with sebaceous follicles. The labia commence at the symphysis pubis, de- Fig- 4U- scend to the perinceum, which is the portion of integument, about an inch and a half in length, between the lit J^ ° e ;':%ffS,filMMP?" ^\\%^ posterior commissure of the labia and the anus. This commis- sure is called frcenum labiorum, frcenulum pe- rinei orfourchette. The opening between the labia is the vulva or External Organs of Generation in the Unmarried Female— fossa magna. At the the Vulva being partially opened. Upper junction of the 1,1. Labia majora. 2. Fourchette. 3. Moils veneris. 4. Prfepu- lnKifl ar\c\ witVnn thpm Hum clitoridis around glans clitoridis. 5. Vestibulum. 6. Nymphje. i*^'i <*iiu wiuuu mem, 7. Meatus urinarius. 8. Hymen, open in its central portion and ft, small OrffaU exists surrounding inferior extremity of the vagina. 9. Perineum. 10. -., -. -.. . Anus. called clitoris or super- labia, which greatly resembles the penis. It is formed of corpora cavernosa, and is ter- minated anteriorly by the glans, which is covered by a prepuce con sisting of a prolongation of the mucous membrane of the vagina. Unlike the penis, however, it has no corpus spongiosum or urethra attached to it; but is capable of being made erect by a mechanism similar to that which exists in the penis; and it has two erector mus- cles, the erectores clitoridis, similar to the erectores penis. Anciently, if a female was detected a fourth time in incontinence in the vicinity of the Superior Courts of Westminster, the clitoris was amputated in open court.2 Extending from the prepuce of the clitoris, and within the labia majora, are the labia minora or nymphoz, the organization of which is similar to that of the labia majora. They gradually enlarge as they pass downwards, and disappear when they reach the orifice of the vagina. A singular variety is observed in the organization of those parts amongst the Bosjesmen or Bushmen, a tribe to whose peculiarities of organization we have already had occasion to refer. Discordance has, however, prevailed regarding the precise nature of this peculiarity,— some describing it as existing in the labia; others in the nymphse, and 1 Chitty*s Practical Treatise on Medical Jurisprudence, Pt. i. p. 390, American edit., Philad., l**Jb'. * Chitty, op. cit., Pt. i. p. 391, Amer. edit., Philad., 1836. GENERATIVE APPARATUS—FEMALE. 389 others again, in a peculiar organization; some, again, deeming it natu- ral, others artificial. Dr. Somerville,1 who had numerous opportuni- ties for observation and dissection, asserts, that the mons veneris is less prominent than in the European, and is either destitute of hair, or thinly covered by a small quantity of a soft, woolly nature; that the labia are very small, so that they seem at times to be almost wanting ; that the loose, pendulous, and rugous growth, which hangs from the pudendum, is a double fold; and that it is proved to be the nymphae, by the situation of the clitoris at the commissure of the folds, as well as by all other circumstances; and that they sometimes reach five inches below the margin of the labia: Le Vaillant2 says nine inches. Cuvier3 examined the Hottentot Venus, and found her to agree well with the account of Dr. Somerville. The labia were very small; and a single prominence descended between them from the upper part. It divided into two lateral portions, which passed along the sides of the vagina to the inferior angle of the labia. The whole length was about four inches. When she was examined naked by the French Savans, this formation was not observed. She kept the tablier, ventrale cuta- neiiri),or, as it is termed by the Germans, S c h ii r z e (" apron,") carefully con- cealed, either between her thighs, or yet more deeply; and it was not known, until after her death, that she possessed it. Both Sir John Bar- row4 and Dr. Somerville deny, that the peculiarity is induced artificially. In warm climates, the nymphae are often greatly and inconveniently elon- gated, and amongst the Egyptians and other Af- rican tribes, it has been the custom to extirpate them, or diminish their size. This is what is meant by circumcision in the female. The vagina is a canal, which extends between the vulva and uterus, the neck of which it em- 1 Medico-Chirurgical Transactions, vii. 157. 2 Voyage dans l'lnterieur d'Afvique, p. 371. 3 Memoir, du Museum, iii. 2b'6; and Broc, Essai sur les Races Humaines, p. 87, Paris, 1835. 4 Travels into the interior of Southern Africa, p. 279 ; also, Lawrence's Lectures on Comparative Anatomy, Physiology, Zoology, &c, 9th edit., p. 289, Lond., 1844. Fig. 412. Side View of Viscera of Female Pelvis. 1. Symphysis pubis. 2. Abdominal parietes. 3. Fat forming the mons veneris. 1. Bladder, a. Entrance of left ureter. 6. Canal of urethra. 7. Meatus urinarius. 8. Clitoris and its pre- puce. 9. Left nympha. 10. Left labium majus. 11. Orifice of vagina. 12. Its canal and transverse rugae. 13. Vesico-vaginal septum. 11. Vagino-rectal septum. 15. Seetiou of perineum. 16. Os uteri. 17. Cervix uteri. 18. Fundus uteri. 19. Rectum. 20. Anus. 21. Upper portion of rectum. 22. Eecto-uterine fold of peritoneum. 23. Utero-vesical reflection of peritoneum. 24. Peritoneum reflected on the bladder from abdominal parietes. 2.5. Last lumbar vertebrse. 26. Sacrum. 27. Coccyx. 390 GENERATION". braces. It is sometimes called vulvo-uterine canal, and is from four to six inches long, and an inch and a half, or two inches, in diameter. It is situate in the pelvis, between the bladder before, and the rectum behind; is slightly curved, with the concavity forwards, and narrower at the middle than at the extremities. Its inner surface has numerous —chiefly transverse—rugae, which become less in the progress of ao-e after repeated acts of copulation, and especially after accouchement. It is composed of an internal mucous membrane, supplied with nume- rous follicles, of a dense areolar membrane; and, between these, a layer of erectile tissue, which is thicker near the vulva; but is, by some, said to extend even as far as the uterus. It is termed the corpus spongiosum vaginoz. It is chiefly situate around the anterior extremity of the- va- gina, below the clitoris, and at the base of the nymphae; and the veins of which it is constituted are called plexus retiformis. The upper portion of the vagina, to a small extent, is covered by peritoneum. The sphinc- ter or constrictor vaginoz muscle sur- rounds the orifice of the vagina, and covers the plexus retiformis. It is about an inch and a quarter wide, and ordinarily about six inches in length; arises from the body of the clitoris, and passes backwards and downwards, to be inserted into the dense, white substance in the centre of the perineum, which is common to the transversi perinei muscles, and the anterior point of the sphincter ani. Near the external aperture of the vagina is the hymen or virginal or vaginal valve, which is a more or less extensive, membranous duplicature, of variable shape, formed by the mu- cous membrane of the vulva, where it enters the vagina, so that it closes the canal more or less completely. It is generally very thin, and easily lacerable: but is sometimes extremely firm, so as to prevent penetra- tion. It is usually of a semilunar shape; sometimes oval from right to left, or almost circular, with an aperture in the middle; whilst, occa- sionally, it is entirely imperforate, and of course prevents the issue of the menstrual flux. It is easily destroyed by mechanical violence of any kind, as by strongly rubbing the sexual organs of infants with coarse cloths, and by ulcerations of the part; hence its absence is not an abso- lute proof of the loss of virginity, as it was of old regarded by the Hebrews, nor is its presence a positive evidence of continence. Indi- viduals have conceived, in whom the aperture of the hymen has been so small as to prevent penetration. Its general semilunar or crescentic shape has been considered to explain the origin of the symbol of the Fig. 413. Lateral View of the Erectile Structures of the External Organs of Generation in the Female, the Skin and Mucous Membrane being removed. a. Bulbus vestibuli. c. Plexus of veins named pars intermedia, e. Glans of the clitoris. /.Body of the clitoris, h. Dorsal vein. I. Right crus of clitoris, m. Vulva, n. Right gland of Bartholine. GENERATIVE APPARATUS—FEMALE. 391 crescent assigned to Diana, the goddess of chastity. Around the part of the vagina where the hymen was situate, small, reddish, flattened, or rounded tubercles—carunculce myrtiformes seu hymenales—afterwards exist, which are of various sizes; and are formed, according to the Fig. 414. Front View of the Erectile Structures of the External Organs of Generation in the Female. ^ a. Bulbus vestibuli. 6. Sphincter vaginae muscle, e, e. Venous plexus, or pars intermedia. /. Glans of the clitoris, g. Connecting veins, h. Dorsal vein of the clitoris, k. Veins going beneath pubes. I. The obturator vein. general opinion, by the remains of the hymen. MM. Beclard and J. Cloquet1 consider them to be folds of mucous membrane. Their num- ber varies from two to five, or six. Fig. 415. Anterior View of the Uterus and Appendages. n. Fundus, 6, body, and c, cervix or neck of the uterus, e. Front of the upper part of the vagina, n, n. Round ligaments of the uterus. r,r. Broad ligaments, s, s. Fallopian tubes, t. Fimbriated extremity. u. Ostium abdominale. The position of the ovaries is shown through the broad ligaments ; and also the cut edge of the peritoneum, along the lower border of the broad ligaments and across the uterus. 1 Dictionnaire de Medecine, &c, art. Caroncule, Paris, 1821. 392 GENERATION. At either side of the entrance of the vagina, beneath the integument covering its inferior part, as well as the superficial perineal fascia, and the constrictor vaginae muscle, are situate the glinds of Duverney or of Bartholin. The space they occupy lies between the lower end of the vagina, the ascending ramus of the ischium, the crus clitoridis, and the erector clitoridis muscle. The excretory duct is at the anterior edge of the superior part of the gland, and runs beneath the constrictor vaginae, horizontally forwards and inwards, to the inner face of the nympha, Fig. 416. Posterior View of the Uterus and its Appendages : the Cavity of the Uterus being shown by the removal of its Posterior Wall; and the Vagina being laid open. a. Fundus, b, body, and c. cervix of the uterus, laid open. The arbor vitas is shown in the cervix. d. The os uteri externum, laid open. e. The interior of the upper part of the vagina. /. Section of the walls of the uterus, i. Opening into Fallopian tube. o. Ovary, p. Ligament of ovary, r. Broad liga- ment. 8. Fallopian tube. t. Fimbriated extremity. opening in front of the carunculas myrtiformes in the midst of a num- ber of small mucous follicles. These glands secrete a thick, tenacious, grayish-white fluid, which is emitted in considerable quantity towards the termination of sexual intercourse, and—it has been suggested— through the spasmodic contraction of the constrictor vaginae muscle under which they lie. When proper attention to cleanliness is not paid, so that the secre- tion from the mucous membrane of the vagina is no longer healthy, an animalcule—the trichomonas vaginalis—has been detected in it by M. Donne;1 with occasionally small vibriones, which can only be seen when magnified three or four hundred times. (Fig. 417.) Donne, Dujardin, and Kaspail regard it as an infusory animalcule; Froriep and Ehren- berg as a species of acarus; whilst Gluge, Lebert, Valentin, Siebold, Wagner, and Vogel2 are of opinion, that it is not an animal, but ciliated epithelium separated from the uterus. Kolliker and Scanzoni3 have, 1 Cours de Microscopie, p. 157, Paris, 1844; and Atlas, Paris, 1845. 2 The Pathological Anatomy of the Human Body, by Julius Vogel, translated, &c, by G. E. Day, p. 440, Lond., 1847. 3 Gazette Hebdomadaire, Mai 18, 1855 ; and Edinb. Med. Journ., Oct., 1855, p. 367. GENERATIVE APPARATUS—FEMALE. 393 however, made it a subject of fresh research, and have discovered in it all the characters of the true infusoria, and such as closely resemble those described by M. Donne'. Fig. 417. Vaginal Mucus containing Trichomonads, magnified 400 diameters. b, b, b. Purulent globules, c, c, c, c. Trichomonads. The vagina is at times double. Three such cases have been recorded by Professor Meigs.1 The uterus is a hollow organ for the reception of the foetus, and its retention during gestation. It is situate in the pelvis, between the bladder—which is before, and the rectum behind, and below the con- volutions of the small intestines. Fig. 412 gives a lateral view of their relative situation. It is of a conoidal shape, flattened on the anterior and posterior surfaces; rounded at the base, which is above, and trun- cated at its apex, which is beneath. It is of small size; its length being only about two and a half inches; breadth one and a half inch at the base, and ten lines at the neck; thickness about an inch. It is divided into the fundus, body, and cervix or neck. The fundus is the upper part of the organ above the insertion of the Fallopian tubes. The body is the part between the insertion of the tubes and the neck; and the neck is the lowest and narrowest portion, which projects and opens into the vagina. At each of the two superior angles are—the opening of the Fallopian tube, the attachment of the ligament of the ovary, and that 1 Medical Examiner, for December, 1846, p. 703. 394 GENERATION. 6f the round ligament. The inferior angle is formed by the neck, which projects into the vagina to the distance of four or five lines, and terminates by a cleft, situate crosswise, called os tincoz, os uteri or vaginal orifice of the uterus. The aperture is bounded by two lips, which are smooth and rounded in those that have Fig. 418. not had children; jagged and rugous in those who are mothers,—the anterior lip being somewhat thicker than the posterior. It is from three to five lines long, and is generally more or less open, especially in those who have had child- ren. The internal cavity of the uterus is very small in proportion to the bulk of the organ, owing to the thickness of the parietes, which almost touch in- ternally. It is divided into the cavity of the body, and that of the neck. (Fig. 418.) The former is triangular. The tubes open at its upper angles. The second cavity is more long than broad; is broader at the middle than at either end; and at the upper part where it communicates with the cavity of the body of the uterus an opening exists, called internal orifice of the uterus; the external orifice being the os uteri. The Section of Uterus. inner surface has several transverse rugae, which are not very prominent. It is covered by fine villi, and the orifices of several mucous follicles are visible. The precise organization of the uterus has been a topic of interesting inquiry amongst anatomists. It is usually considered to be formed of two parts, a mucous membrane internally, and the proper tissue of the uterus, which constitutes the principal part of the substance. The mucous membrane has been esteemed a prolongation of that which lines the vagina. It is very thin; of a red hue in the cavity of the body of the organ; white in that of the neck. Chaussier, Eibes, and Madame Boivin, however, deny its existence. Chaussier asserts, that having macerated the uterus, and a part of the vagina, in water, vinegar, and alkaline solutions; and having subjected them to continued ebullition, he always observed the mucous membrane of the vagina stop at the edge of the os uteri; and Madame Boivin,—a well-known French authoress on obstetrics, who has attended carefully to the anatomy of those organs during pregnancy,—says, that the mucous membrane of the vagina terminates by small expansible folds, and by a kind of pre- puce, under the anterior lip of the os uteri. In their view, the inner surface of the uterus is formed of the same tissue as the rest of it. The epithelium of the vagina differs, however, from that of the uterus. It is columnar and ciliated as far down as the middle of the cervix uteri, below which it becomes tesselated or squamous, like that of the vagina. GENERATIVE APPARATUS—FEMALE. 395 When examined with a lens, the mucous membrane is found to be marked over with minute dots, which are the orifices of numerous simple tubular glands; some of these are branched and others slightly twisted into a coil. They can be seen in the virgin uterus; but become enlarged on impregnation. The proper tissue of the organ is dense, compact, not easily cut, and somewhat resem- bles cartilage in colour, resistance, and elasti- city. It is a whitish, ho- mogeneous substance, penetrated by numerous minute vessels. In the unimpregnated state, the fibres, which enter into the composition of the tissue, appear liga- mentous, and pass in everydirection,but so as to ])< rmit the uterus to be more readily lacerated from the circumference to the centre than in any other direction. The precise character of the tissue has been a matter of contention amongst anatomists. The microscope shows it to be composed of muscular fibres of the unstriped variety, inter- lacing with each other, but disposed in bands and layers, intermixed with much fibro-areolar tissue, a large number of bloodvessels and lymphatics, and a few nerves. The arrangement of the muscular fibres is best studied at an advanced period of utero-gestation. Besides the usual organic constituents, the uterus has arteries, veins, lymphatics,and nerves. The arteries proceed from two sources;—the spermatic, which are chiefly distributed to the fundus of the organ, and towards the part where the Fallopian tubes terminate; and the hypogastric, which are sent especially to the body and neck. Their principal branches are readily seen under the peritoneum, which covers the organ ; they are very tortuous; frequently anastomose, and their ramifications are lost in the tissue of the viscus, and on its inner surface. The veins empty themselves partly into the spermatic, and partly into the hypogastric. They are even more tortuous than the arteries; and, during pregnancy, dilate and form what have been termed uterine sinuses. The nerves are derived partly from the great sympathetic, and partly from the sacral pairs. The arrangement of the uterine nerves has given rise to much difference of sentiment. Whilst Dr. Lee1 considers that the uterus is 1 The Anatomy of the Nerves of the Uterus, Lond., 1841; Philosophical Transactions for 1842; and Lectures on the Theory and Practice of Midwifery, Amer. edit., p. 10S, Philad., 1S44 ; see, also, W. Tvler Smith, Parturition, and the Principles and Practice of Obstetrics, p. 79, Philad., 1849. Fig. 419. Section of the Paries of the Uterus magnified three diameters. The right hand portion is the fibrous structure of the uterus ; the left hand the lining membrane and tubular glands. The arrange- ment of the vessels accompanying these is shown. 396 GENERATION. most copiously supplied with them; others—as Mr. Beck,1 Dr. Sharpey1 and M. Boulard3—have supposed, that he mistook for nerves other structures; and that the number of uterine nerves is by no means great. The uterus is sometimes absent.4 The appendages of the uterus are:—1. The ligamenta lata or broad ligaments, which are formed by the peritoneum. This membrane is reflected over the anterior and posterior surfaces and over the fundus of the uterus; and the lateral duplicatures of it form a broad expansion, and envelope the Fallopian tubes and ovaria. These expansions are the broad ligaments. (See Figs. 415 and 416.) 2. The anterior and posterior ligaments, which are four in number and are formed by the peritoneum. Two of these + Fig. 420. pass from the uterus to the bladder,—the anterior; and two between the rectum and uterus—the posterior. 3. The lignmenta rotunda or round ligaments, (Fig. 415,) which are about the size of a goose- quill, arise from the superior angles of thefundus uteri, and, proceeding obliquely down- wards and outwards, pass out through the abdominal rings to be lost in the areolar tissue of the groins. They are whit- ish, somewhat dense cords, formed by a collection of tor- tuous veins and lymphatics, nerves, andlongitudinal fibres, which were, at one time, be- lieved to be muscular, but a re now generally considered to consist of condensed areolar tissue. 4. The Fallopian or uterine tubes; two conical, tortuous canals, four or five inches in length; situate in the same broad ligaments that contain the ovaries, and extending from the superior angles of the uterus as far as the lateral parts of the brim of the pelvis. (Figs. 415, 416, and 411.) The uterine extremity of the tube (Figs. 416 and 421) is extremely small, and opens into the uterus by an aperture so minute as scarcely 1 Philosophical Transactions, part 2, for 1846. 2 Quain's Human Anatomy, by Quain and Sharpey, Amer. edit., by Dr. Leidy, ii. 356, Philad., 1849. 3 Comptes Rendus des Seances et Mcmoires de la Societe de Biologie, Tom. 3, p. 86, Annee, 1851. 4 For such cases, see Dr. Chew, Amer. Journ. Med. Sciences, May, 1840, p. 39; also, Dr. Meitw, translation of Colombat de l'lsere on Diseases of Females, p. 119, Philad., 1845. Nerves of the Uterus. GENERATIVE APPARATUS — FEMALE. 397 to admit a hog's bristle. The other extremity is called pavilion. It is trumpet-shaped, fringed, and commonly inclined towards the ovary, to which it is attached by one of its longest fimbriae. This Fig. 421. fringed portion is called corpus jimbriatum or morsus diaboli. The Fallopian tubes, conse- quently, open at one end into the cavity of the uterus, and at the other, through the peri- toneum into the cavity of the abdomen. They are covered externally by the broad liga- ment or peritoneum; are Fallopian Tube. lined internally by a mucous membrane, which is soft, villous, and has many longitudinal folds; and between these coats is a thick, dense, whitish membrane, which is pos- sessed of contractility; although muscular fibres cannot be detected in it. Santorini asserts that in robust females the middle membrane of the tubes has two muscular layers; an external, the fibres of which are longitudinal; and an internal, whose fibres are circular. » M. Kaciborski,1 in a memoir read to the Academie Royale des Sciences of Paris, states it to be a general rule, that the extremities of the Fal- lopian tube in domestic animals are so placed during the act of fecun- dation as to envelope the entire ovary, either directly by means of the open trumpet-shaped extremity, or indirectly by the aid of the fimbri- ated extremity. In women, however, the fimbriated extremity embraces but a small portion of the ovary; and he thinks, that this anatomical peculiarity is the cause of extra uterine conception being so much more common in them than in domestic animals. In the latter, indeed, it is very rare. The ovaries (Figs. 416 and 422) are two ovoid bodies, of a pale red colour; rugous, and nearly of the size of the testes of the male. They are situate in the Fig- 422- cavity of the pelvis, and are contained in the posterior fold of the broad ligaments of the uterus. At one time they were conceived to be glandular, and were called the female testes; but as soon as the notion prevailed that they contained ova, the term ovary or egg vessel was given to them. The external extremity of the ovary has attached to it one of the prin- Section of Ovary. cipal fimbriae of the Fallopian tube. The inner extremity has a small fibro-vascular cord inserted into it; this passes to the uterus, to which it is attached behind the insertion of the Fallopian tube ; and a little lower. It is called ligament of the ovary, and is in the posterior ala of the broad ligament. It is solid, and has no canal. The surface of the ovary has many round prominences, and the peritoneum—forming the indusium—envelopes the whole of it, 1 Gazette MJdicale de Paris, 25 Juin, 1S42. 398 GENERATION. except at the part where the ovary adheres to the broad ligament. The precise nature of its parenchyma or stroma is not determined. When torn or divided longitudinally, as in Fig. 422, it appears to be constituted of a cellulo-vascular tissue. In this, there are spherical vesicle—ovula Graafiana, folliculi Graafiani, follicles of De Graafi Graafian follicles ovi-capsules or ovisacs. Roederer1 asserts, that he found in the ovary of one woman thirty, in that of another about fifty. These are filled with an albuminous fluid, which is colourless or yellowish, and may be readily seen by dividing the vesicles carefully with the point of a fine scissors. The examinations of recent histologists, however, show, that the number is far beyond that mentioned by Roederer and others. At the period of puberty, the stroma of the ovary is crowded with ovisacs, which are still so minute, that in the cow, according to the computation of Dr. Barry, a cubic inch would contain 200 millions of them. Fluid from the ovary of a mare was examined by M. Las- saigne, and found to contain albumen, with chlorides of sodium and potassium. In the lower animals, the ovary consists of a loose tissue, containing many cells, in which the ova are formed, and from which they escape by the rupture of the cell-walls: in the higher animals, as in the human female, tl»e tissue is more compact, and the ova, except when they are approaching maturity, can only be distinguished by the aid of a high magnifying power. The microscopic analysis of the ovum has greatly engaged the atten- tion of modern histologists, who have materially extended our knowledge in regard to it; although wehavestill much to learn. In the egg of the fowl, the parts more interesting in the present relation are the yolk membrane and its contents; for neither the albumen which forms the white, nor the shell membrane with its calcareous covering, exists in the ovum whilst in the ovary. They are added during its passage through the oviduct. Within the yolk, or vitellary membrane—cuticula vitelli—is the yolk —vitellus—consisting partly of albumi- nous granules, and partly of oil globules. Towards the centre, the yolk changes in some degree, being of a lighter co- lour, and the granules having more the appearance of cells, with minuter glob- ules in their interior. The central portion is termed discus vitellinus. In the centre of the yolk of the unripe ovule is a larger cell, distinct in appearance from the rest, and having a nucleus in its walls. This is the germinal vesicle, or vesicle of Purkinje, so called from its first describer, and the nucleus is the germinal spot. In man and the mammalia, the ova contain the same Fig. 423. New-laid Egg with its Molecule, &c. 1 Stannius, art. Eierstock, in Encyclop. Worterb., u. s. w., x. 188, Berlin, 1836. GENERATIVE APPARATUS—FEMALE. 399 parts; but, even when advanced, they are exceedingly minute, owing to the small quantity of vitellus that enters into their composition. The ripest ovum in the ovary of the human subject, and of the mam- malia, does not generally measure more than from the fifteenth to the twentieth part of a line in diameter: it rarely happens, that they are as much as y^th of a line. They vary, according to Bischoff, from 5|5th to y^oth of an incn> Under the microscope, the Graafian vesicle is found to consist of an external and an internal membrane. The former—tunic of the ovisac, of Dr. Barry,1 is extremely vascular; the latter, ovisac of the same observer—membrana propria of some—vesicule ovulifh-e of M. Pouchet2—is smooth and velvety, and derives its vessels from the former. The cavity, enclosed by these membranes, is far from being filled by the ovum; it contains, besides, a whitish or yel- lowish albuminous mass, which consists chiefly of granules, from the three hundredth to the two hundredth part of a line in diameter, con- nected together by a tenacious fluid, forming the membrana granulosa, —couche celluleuse of M. Coste.3 Its density is unequal, and, towards some part of the periphery of the vesicle, these granules are accumu- lated in a disk-like form, making a slight prominence, in which there is a depression. The disk is termed by Von Baer discus proligerus ; and it has been called discus vitellinus. The prominence has been Fig. 424. Constituent parts of Mammalian Ovum. A. Entire. B. Ruptured, with the contents escaping, m v. Vitelline membrane, j. Yolk, v g. Ger- minal vesicle, t g. Germinal spot. named cumulus, germinal cumulus, cumulus proligerus, nucleus cicatri- culoz and nucleus blastodermatis. Dr. Barry likewise observed certain granular cords, resembling both in appearance and function the chalazae of the egg, which he has called retinacula, but which Bischoff does not admit. A small cup-like cavity in the cumulus receives the ovum. The ovum is surrounded by a thick white ring, which has been called zonapellucida, and has been considered to be a membrane; but, accord- ing to Mr. T. W. Jones, is now pretty generally acknowledged to be "the optical expression of the circumferential doubling of a thick trans- parent membrane, which encloses the yolk." Within this, is a granular 1 Philos. Transact, for 1838. 2 Theorie positive de l'Ovulation spontanee, p. 44, Paris, 1847. 3 Histoire generate et particuliere du Developpement des Corps Organises, i. 163, Paris, 1847. 400 GENERATION. layer—the vitellus or yolk—the larger granules of which are superficial and compact; whilst, internally, it is a clear albuminous fluid almost Fig. 425. Fig. 426. Ovum of the Sow. 1. Germinal spot. 2. Germinal vesi- cle. 3. Yolk. 4. Zona pellucida. 5. Discus proligerus. 6. Adherent gra- nules or cells. Diagram of a Graafian Vesicle, containing an Ovum. 1. Stroma or tissue of the ovary. 2 and 3. External and in- ternal tunics of the Graafian vesicle. 4. Cavity of the vesicle, ;">. Thick tunic of the ovum or yolk-sac. 6. The yolk. 7. The germinal vesicle. 8. The germinal spot. Fie. 427. Ovarium laid open, with Graafian vesicles in various stages of evolution. At p, is shown the expanded fimbria of the Fallopian tube, near which is seen to project from the sur- face of the ovary a Graafian vesicle, v, the rupture of which has allowed an ovule, ce, surrounded by its discus proligerus, c, to escape;—in the centre of the upper part of the figure is shown an emptied Graa- fian vesicle, v, laid open by the incision, and showing the irregular cavity, g ;—further up, towards the left, is seen another Graafian vesicle, with the ovum c, not yet discharged. Other Graafian vesicles, v, v, t), in earlier stages of developement, are seen in different parts of the figure. GENERATIVE APPARATUS—FEMALE. 401 devoid of granules. Imbedded in the vitellus, but nearer its circum- ference than its centre, is the germinal vesicle or vesicle of Purkinje, first seen in the mammalia by M. Coste,1 which appears like a clear ring of very small size, and measures in man and the mammalia not more than B',,th part of a line in diameter. Upon a particular part of the germinal vesicle is observed the macula germinativa or germinal spot, which pre- sents itself as a rounded granular formation attached to the inner wall of the germinal vesicle. All these parts are represented in Fig. 426. Wagner2 thinks the germinal vesicle may be viewed as a cell—a pri- mary cell—of which the germinal spot forms the nucleus, and that it would perhaps be well to style the germinal spot germinal nucleus. It was elsewhere remarked,3 that the formation of the ovule by the Graafian follicle must be regarded as a true secretion,—the yolk of which it is mainly composed as well. as the membrana granulosa essentially resembling each other in histolo- FiS-42s- gical and chemical cha- racter. When maturated, the ovum, pressed for- ward probably by fresh depositions of the yellow matter which goes to the formation of the granu- lar membrane and the yolk, is discharged from the ovary, and laid hold of by the Fallopian tube, which acts as an excre- tory duct, and conveys it into the interior of the uterus. The observations of Cams4 have shown, that the vesicles of De Graaf exist even in the foetus; and according to Dr. Ritchie,5 it would seem that during the period of childhood, there is a continual rupture of ovi- sacs, and discharge of ova at the surface of the ovarium.6 The ovaria are studded with numerous minute copper-coloured spots; and their surface presents delicate vesicular elevations, occasioned by the most 1 Bischoff, Traite" du Developpement de l'Homme et des Mammiferes, traduit par Jourdan, p. 6, Paris, 1843. 2 Human Physiology, translated by R. Willis, p. 43, Lond., 1841. 3 Vol. i. p. 507. 4 Gazette Medicale de Paris, Aug. 12, 1837. 6 Lond. Med. Gazette, 1844. 6 Kirkes and Paget, Handbook of Physiology, Amer. edit., p. 461, Philad., 1849. VOL. II.—2b' Ovarium of the living Hen, natural size. ferent stages of evolution The Ova at dif- 402 GENERATION. matured ovisacs: the escape of these takes place by minute puncti- form openings in the peritoneal coat, and no cicatrix is left. The different conditions of progress towards maturation are well seen in the ovary or yolk bag of the common fowl. > The arteries and veins of the ovaries belong to the spermatic. The arteries pass between the two layers of the broad ligament to the ovary, assuming there a beautiful convoluted arrangement, very simi- lar to the convoluted arteries of the testis. These vessels traverse the ovary nearly in parallel lines, as in the marginal figure, forming numerous minute twigs, which have an irregular knotty appearance, from their tortuous condition; and appear to be chiefly distributed to the Graafian vesicles. The nerves of the ovaries, which are extremely delicate, are from the renal plexuses; and their lymphatics communi- cate with those of the kidneys.1 Such is the anatomy of the chief organs concerned in the function of generation. Those of lactation will be described hereafter. 1. MENSTRUATION. Before proceeding to the physiology of generation, there is a func- tion, peculiar to the female, which requires consideration. This con- sists in a periodical discharge of blood from the vulva, occurring from three to six days in every month, during the whole time that the female is capable of conceiving,—or from the period of puberty to what has been termed the critical age. This discharge is called cata- menia, menses, flowers, he., and the process menstruation. It has been considered peculiar to the human species; but MM. Geoff'roy St. Hi- laire, and F. Cuvier, assert, that they have discovered indications of it in the females of certain animals. It has been denied, however, that this is anything more than the exudation of a bloody mucus. At the present day, however, menstruation is maintained by many to be iden- tical with the rut of animals. In some females, it is established suddenly, and without any premo- nitory phenomena; but in the greater number it is preceded and ac- companied by some inconvenience. The female complains of signs of plethora or general excitement,—indicated by redness and heat of skin, heaviness in the head, oppression, quick pulse, and pains in the back or abdomen. The discharge commences drop by drop, but con- tinuously ; during the first twenty-four hours, the flow is not as great as afterwards, and is more of a serous character; but, on the following day, it becomes more abundant and sanguineous, and gradually sub- sides, leaving, in many females, a whitish, mucous discharge, techni- cally termed leucorrhoza, and, in popular language, the whites. The quantity of fluid lost, during each menstruation, varies greatly according to the individual and the climate. Its average is supposed to be from six to eight ounces in temperate regions. By some, it haa been estimated as high as twenty. Dr. Meigs2 states, that he has met with many healthy women, who informed him, that they never used a napkin; so that, he observes, it is not possible to conceive, that in such 1 See Kobelt De l'Appareil du Sens Genital des deux Sexes, traduit de l'Allemand, par H. Kaula, D. M., Strasbourg & Paris, 1851. 2 Edit, of Colombat de l'Isere on the Diseases, &c, of Females, p. 33, Philad., 1845. MENSTRUATION. 403 persons the loss amounts to more than three or four ounces. It is dif- ficult, indeed, to imagine that it can amount to so much. On the other hand, he is confident, that many healthy females lose at least 20 ounces at each period. The fluid proceeds from the interior of the uterus, and not from the vagina. At one time, it was believed, that in the intervals between the flow of the menses, the blood gradually accumulates in some parts of the uterus, and when these parts attain a certain degree of fulness, they give way, and it flows. This office was ascribed to the cells, which were conceived to exist in the substance of the uterus between the uterine arteries and veins,—and, by some, to the veins themselves, which, owing to their great size, were presumed to be reservoirs, and hence called uterine sinuses. The objection to these views is,—that we have no evidence of the existence of any such accumulation; and that when the interior of the uterus of one who has died during menstruation is examined, there are no signs of any such rupture as that described; the enlarged vessels exist only during pregnancy or during the expanded state of the uterus; the veins in the unimpreg- nated organ are small, and totally inadequate for such a purpose. The menstrual fluid is\a true exhalation, effected from the inner sur- face of the uterus. This is evident from the change in the lining mem- brane of the organ during the period of its flow, which is rendered softer and more villous, and exhibits bloody'spots, with numerous pores from which the fluidf may be expressed. An injection, sent into the arteries of the uterus, also readily transudes through the lining mem- brane. The appearance of the menstrual fluid in the cavity of the uterus, during the period of its flow; its suppression in various morbid conditions of the organ; and the direct evidence, furnished to Euysch, Blundell,1 Sir C. Clarke,2 and others, in cases of prolapsus or inversio uteri, where the fluid has been seen distilling from the uterus, likewise show that it is a uterine exhalation. Much discussion has occurred as to whether the catamenia are the result of simple hemorrhage; or are a true secretion from the uterine blood. From ordinary blood they may be distinguished by the smell, which is sui generis, and also by not being coagulable. " It [the men- strual fluid] is," says Mr. Hunter, "neither similar to blood taken from a vein of the same person, nor to that which is extravasated by acci- dent in any other part of the body, but is a species of blood, changed, separated, or thrown off from the common mass by an action of the vessels of the uterus, similar to that of secretion, by which action the blood loses the principle of coagulation, and, I suppose, life." The principle of coagulation does not exist,—according to Lavagna, Toul- mouche, J. Miiller and others,3 owing to the absence of fibrin. Ret- zius4 asserts, that he has detected it in free phosphoric and lactic acids, by the presence of which, he conceives, the fibrin is kept in a state of 1 Principles and Practice of Obstetricy, Amer. edit., p. 49, Washington, 1834. * On Diseases of Females attended with Discharges, Amer. edit., Philad., 1824. 8 Handbuch der Physiologie, Baly's translation, p. 256, Lond., 1837, and p. 1481, Lond., 1842. * Ars. Berattelse af Setterblad, 1835, Seite 19—cited in Zeitschrift fiir die Gesammte Medicin, Marz, 1837, S. 390. 404 GENERATION. solution, and prevented from coagulating. The fluid has the proper- ties, according to Mr. Brande, of a very concentrated solution of the colouring matter of the blood in a dilute serum.1 Dr. Burow2 ex- amined twelve ounces of menstrual blood, which had been retained in the uterus by an imperforate hymen. It was of a dirty reddish-brown colour, of the consistence of syrup, very adhesive, and entirely devoid of odour; abounded in albumen, and was very little susceptible of pu- trefaction. When examined with the microscope, almost all the blood- corpuscles were found to have lost their regular form, and to resemble the granules observed in pus which has been for a long time exposed to the air, or retained within the cavity of an abscess. These blood- corpuscles were suspended in a transparent fluid. On stirring the blood for a considerable time, no perceptible change was produced to the eye; but under the microscope numerous delicate, transparent lamella? were seen floating in the serum, which Dr. Burow regarded as portions of fibrin, a substance sparingly present—as has been re- marked—in menstrual blood. The red colour of the menstrual fluid was found by Remak3 to be owing to the presence of blood-corpuscles, and the intensity of the colour to their number. M. Bouchardat4 analyzed the menstrual fluid, obtained from a female who permitted a speculum to remain in the vagina for ten hours in order that an ounce might be procured. Without this precaution, the fluid becomes mixed with vaginal mucus and urine, as the presence of ammoniaco-magnesian phosphate demonstrates. The following were the results of the analy- sis :—Water, 90*8; fixed matters, 6*92. The fixed matters were com- posed of—fibrin, albumen, and colouring matter, 75*27; extractive matter, 0*42 ; fatty matter, 2*21; salts, 5*31; mucus, 16*79. The female was a patient of M. Briere de Boismont, who considers, that the large proportion of water was due to the delicacy of her frame, and to her subsisting on vegetable diet(?). A specimen of menstrual blood was examined by M. Simon,5 and found to be composed of water, 785*000; solid constituents, 215*000; fat, 2*580; albumen, 76*540; hemato-globulin, 120*400; extractive matters and salts, 8*600. It contained no fibrin. Its most striking peculiarities were;—the total absence of fibrin, and the increase of solid constituents caused by the excess of blood-corpuscles. The hemato-globulin was found to be very rich in hematin, combined, un- doubtedly, with a considerable amount of hemaphsein. The colouring matter amounted to 8*3 g of the hemato-globulin. Dr. Day6 has, how- ever, little doubt that fibrin exists in the menstrual secretion; but its detection is usually rendered impracticable, owing to the presence of a large amount of mucus, which seems to deprive the blood of its power of coagulating. In an analysis made by M. Denis, and cited by M. Coste,7 the men- 1 Philos. Transact., ciii. 113; and Blundell, op. cit., p. 46. 2 Muller's Archiv., No. vii. 1840; and Brit, and For. Med. Rev., July, 1840, p. 287. 3 Medicinische Zeitung, 25 Dec, 1839. « Briere de Boismont, De la Menstruation, &c, Paris, 1842. 6 Animal Chemistry, by Day, Sydenham edit., p. 337, Lond., 1845. 6 Ibid. 7 Histoire Generale et Particuliere du Developpement des Corps Organises, p. 224, Paris, 1847. MENSTRUATION. 405 strual fluid was found to consist of water, 82*50; fibrin, 0*05; hema- tosin, 6*34; mucus, 4*53; albumen, 4*83; oxide of iron, 0*05; red phosphuretted fat and traces of white phosphuretted fat, 0*39 ; osma- zome and cruorin, of each, 0*11; subcarbonate, chlorohydrate of soda, and chlorohydrate of potassa, of each, 0*95; carbonate of lime and sulphate of lime, 0*25 ; traces of phosphate of magnesia:—the whole consisting of 82*50 watery parts; 10*70 parts in suspension and in globules; and 6*58 parts in solution. Rindskopf analyzed the menstrual discharge of a healthy vigorous girl. It was extremely acid, and contained, on the first anatysis, water, 820*830; solid residue, 179*170; salts, 10*150;—in the second, water, 822*892; albumen and hemato-globulin, 156*457; extractive matter and salts, 20*651. Another specimen of menstrual fluid, ex- amined by M. Donne', presented the following appearances under the microscope. 1. Abundance of ordinary corpuscles of the blood. 2. Vaginal mucus, formed of epidermic scales from the mucous mem- brane. 3. Mucous globules, furnished by the neck of the uterus (?). In more than fifty specimens of the ordinary menstrual fluid, ex- amined by Mr. Whitehead,1 the following were the results:—its acid nature was in every instance unequivocal; its colour was similar to that of healthy venous blood, never so florid as that from the arteries; and it was less viscid than either; it did not coagulate, but occasion- ally—when very profuse owing to over-exertion, mental anxiety, or confinement to a heated atmosphere—clots were observed, which always had an alkaline reaction: under the microscope blood-corpus- cles in linear or irregular groups were always observable, floating in a pale, pinkish serum; and occasionally a few lymph globules were perceptible, with a number of small granular bodies like oil globules: there was always, also, in it a great quantity of epithelial scales of dif- ferent shapes and sizes. So far, therefore, as examinations go, they show, that there is much resemblance between the catamenial discharge and blood. M. Donne,2 indeed, affirms, that they appear to him to differ in no respect; and, that if the former has occasionally an acid reaction, in place of being alkaline like ordinary blood, this is simply owing to its being mixed with a considerable quantity of vaginal mucus, which is always ex- tremely acid; whilst uterine mucus, he affirms, is always alkaline.3 In an analysis, however, by Dr. Letheby,4 of menstrual fluid retained by an imperforate hymen, no fibrin was detected, and it had an alka- line reaction. The question, whether it be a secretion or a periodical hemorrhage is one of slight moment. They, who are of the former opinion, be- lieve, that the fluid differs somewhat from blood as contained in the vessels; and if such difference really exists, they must regard it as a secretion. Moreover, at the commencement and termination of the sanguineous flow, the discharged fluid is certainly a secretion; and prior to, and during the whole of the menstrual period the lining 1 On the Causes and Treatment of Abortion and Sterility, Amer. edit., p. 40, Philad., 2 Cours de Microscopie, p. 139. Paris, 1844. 3 Ibid., p. 155. 4 Lancet, Aug. 2, 1845. 406 GENERATION. membrane is in a state of erethism, and, doubtless, the seat of increased and modified secretion. The occurrence of menstruation is commonly indicated by a peculiar odour in the secretions from the vulva, so cha- racteristic of the act which it announces, that, according to Pouchet from it alone the approach of the catameuia may be predicted.1 They on the other hand, who maintain the latter opinion, believe the fluid to be pure blood, which subsequently becomes mixed with the utero-vagi- nal secretions; and that the peculiar odour is occasioned by such admix- ture. The author has been assured, however, by one observer, that in a case of vicarious catamenial discharge, which took place from the hairy scalp, the peculiar odour was distinctly evinced. This is a point which merits farther observation. That the flow takes place from the arteries and not from the veins, is favoured by the fact, that when injections are sent into the uterine arteries they transude through the lining membrane of the uterus; and the analogy of all the other exhalations is confirmatory of the position. The efficient cause of menstruation has afforded ample scope for speculation and hypothesis. As its recurrence corresponds to a revo- lution of the moon around the earth, lunar influence has been in- voked ; but, before this solution can be admitted, it must be shown, that the effect of lunar attraction is different in the various relative positions of the moon and earth. There is no day in the month, in which numerous females do not commence their menstrual flux; and, whilst the discharge is beginning with some, it is at its acme or decline with others. The hypothesis of lunar influence must therefore be rejected. In the time of Van Helmont,2 it was believed, that a fer- ment; exists in the uterus, which gives occasion to a periodical intes- tine motion in the vessels, and a recurrence of the discharge; but independently of the want of evidence of the existence of such a fer- ment, the difficulty remains of accounting for its regular renovation every month. Local and general plethora have been assigned as causes; and many Of the circumstances, that modify the flow, favour the opinion. The fact of what has been called vicarious menstruation, has been urged in support of this view. In these cases, instead of the menstrual flux taking place from the uterus, hemorrhage occurs from various other parts of the body, as the breast, lungs, ears, eyes, nose, &c, which would appear to indicate, that there is a necessity for the monthly evacuation or purgation, Reinigung, as the French and Germans term it; and that if this be obstructed, a vicarious hemor- rhage may be established; yet the loss of several times the quantity of blood from the arm, previous to, or in the very act of, menstruation does not always prevent, or interrupt the flow of the catamenia; and in those maladies, which are caused by their obstruction, greater relief is afforded by the flow of a few drops from the uterus itself, than of ten times the quantity from any other part. Some of the believers in local plethora of the uterus have main- tained, that the arteries of the pelvis are more relaxed in the female than in the male, and the veins more unyielding; and hence, that the 1 Coste, Histoire Generale et Particuliere du Developpement des Corps Organises, i. 203, Paris, 1847. 2 Opera, edit. 4, p. 440, Lugd. Bat., 1667. MENSTRUATION. 407 first of these vessels convey more blood than the second return. It has been, also, affirmed, that whilst the arteries of the head predomi- nate in man by reason of his being more disposed for intellectual me- ditation, the pelvic and uterine arteries predominate in the female, owing to her destination being more especially for reproduction. Set- ting aside all these gratuitous assumptions, it is obvious that a state, if not of plethora, at least of irritation, must occur in the uterus every month, which gives occasion to the menstrual secretion; but as M. Adelon1 has properly remarked, it is not possible to say why this irri- tation is renewed monthly, any more than to explain, why the predo- minance of one organ succeeds that of another in the progress of age. The function is as natural, as instinctive to the female, as the deve- lopement of the whole sexual system at the period of puberty. That it is connected most materially with the capability of reproduction is shown by the fact, that it does not make its appearance until puberty, —the period at which the young female is capable of conceiving,— and disappears at the critical time of life, when conception is imprac- ticable. It is arrested, too, as a general rule, during pregnancy and lactation; and in amenorrhcea or obstruction of the menses, fecunda- tion is not readily effected. In that variety, indeed, of menstruation, which is accomplished with much pain at every period, and is accom- panied by the secretion of a membranous substance having the shape of the uterine cavity, conception may be esteemed impracticable. Professor Hamilton, of the University of Edinburgh, was in the habit of adducing this in his lectures, as one of two circumstances—the other being the want of a uterus—that are invincible obstacles to fe- cundation. Yet, in the case of dysmenorrhoea of the kind mentioned, if the female can be made to pass one monthly period without suffer- ing, or without the morbid secretion from the uterine cavity, she may become pregnant, and the whole of the evil be removed: for, the effect of pregnancy being to arrest the catamenia, the morbid habit is usually got rid of during gestation and lactation ; and may not subsequently recur. Gall2 strangely supposed, that some general but extraneous cause of menstruation exists, other than the influence of the moon; and affirms, that in all countries females generally menstruate about the same time;—that there are, consequently, periods of the month in which none are in that condition; and he affirms, that all females may, in this respect, be divided into two classes;—the one comprising those who menstruate in the first eight days of the month, and the other, those who are " unwell"—as it is termed by them in some countries— in the last fortnight. He does not, however, attempt to divine what this causB is. We are satisfied, that his positions are erroneous. Ob- servation has led to the knowledge, already stated, that there is no period of the moon at which the catamenial discharge is not taking place in some; and we have not the slightest reason for supposing, that, on the average, more females are menstruating at one part of the month than at another. It would seem, however, that there are cir- 1 Physiologie de l'Homme, 2de edit., iv. 48, Paris, 1829. 1 Sur les Fonctions du Cerveau, iv. 355. 408 GENERATION. cumstances in the economy, which, as in the case of fevers, give occa- sion to something like periodicity at intervals of seven days;—for ex- ample, Mr. Roberton,1 of Manchester, England, asserts, that of 100 women, the catamenia returned every fourth week in 68; every third week in 28; every second week in 1; and at irregular intervals in 10* these varieties usually existing as family and constitutional peculiarities. It is scarcely necessary to notice the visionary speculations of those who have regarded menstruation as a mechanical consequence of the erect attitude; or the opinion of Roussel,2 that it originally did not exist, but was produced artificially by too succulent and nutritious a regimen, and afterwards propagated from generation to generation; or, finally, that of Aubert, who maintained, that if the first amorous incli- nations were satisfied, the resulting pregnancy would totally prevent the establishment of menstruation. The function, it need scarcely be repeated, is instinctive; and forms an essential part of the female con- stitution. MM. Negrier, Gendrin,3 and others, have revived a view entertained by Mr. Cruikshank, Dr. Power,4 and others, that menstruation is de- pendent upon changes occurring periodically in the ovary. Many cases have been re- Fig. 429. lated by Cruikshank, Robert Lee, Gendrin, Negrier, Bischoff, Pouchet, and others,1 in which, on the dis- section of females, who had died during menstruation, evi- dences have been af- forded of the rupture of an ovarian vesicle, and of a small, irre- gular rupture or ci- catrix in the coats of Ovary of a Female dying during Menstruation. the Ovarium, as re- presented in the mar- ginal figure, which communicated with the remains of a Graafian vesi- cle ; whence it has been inferred, that during the whole of that period of life when the capability for conception continues, there is a con- stantly successive developement of vesicles and their contained ovules in the ovary, and that, at each epoch of menstruation, a vesicle having reached the surface of the ovary becomes the seat of a peculiar organic action, in which all the organs of generation participate; and that the result of this action is the rupture of the vesicle, and the loss of the infecund ovum, either by expulsion from the uterus or by destruction 1 Edinb. Med. and Surg. Journal, xxxviii. 237. 2 Systeme Physique, &c, de la Femme, p. 13, Paris, 1809. 3 Traite Philosophique de M decine Pratique, Paris, 1838-9. * An Essay on the Periodical Discharge, &c, London, 1832. 5 See, on this subject, Coste, Histoire G<-ntrale et Particuliere du Dcveloppement des Corps Organises, p. 19&, Paris, 1847. MENSTRUATION. 409 in the ovary. Subsequently, M. Raciborski1 maintained as the result of his researches,—First. That there exists the most intimate con- nexion between the Graafian vesicles and menstruation. When the vesicles arrive at their full developement, menstruation commences, and when they are destroyed it ceases. Secondly. At each menstrual period, a follicle projects like a nipple on the surface of the ovary, where it afterwards bursts, without requiring for that purpose any venereal excitement. Thirdly. The rupture of the follicles generally appears to take place at the period when the menstrual discharge is stopping; and Fourthly. The ovaries do not act alternately, as has been affirmed;—in this respect not seeming to be under any fixed law. In a more recent work,2 he asserts the doctrine, that the catamenia are but a secondary phenomenon in menstruation properly so called; that the capital phenomenon is the maturation and periodical discharge (ponte) of ova; and hence a woman may give birth to several children with- out ever having seen the catamenia.3 Of late years, much attention has been given to this subject, and by none more than by Dr. Ritchie,4 of Glasgow. As before re- marked, this gentleman affirms, that even during the period of childhood, there is a continual rupture of ovisacs, and discharge of ova at the surface of the ovary. About the period of puberty— he states—a marked change usually takes place in the mode in which the ovisacs discharge their contents; but this change does not necessarily occur simultaneously with the first appearance of the catamenia. The ovaries now receive a much larger supply of blood, and the ovisacs exhibit a great increase of bulk and vascularity, so that when they appear at the surface of the ovary, they resemble pisiform turgid elevations; and the discharge of their contents leaves a much larger cicatrix, and is accompanied by an effusion of blood into their cavities. It would appear, however, from Dr. Ritchie's observa- tions, that although this discharge takes place most frequently at the menstrual period, the two occurrences are not necessarily coexistent; for menstruation may occur without any such rupture; and, on the other hand, the maturation and discharge of mature ova may occur in the intervals of menstruation, and even at periods of life when that function is not taking place—as before the age of puberty;5 and Dr. Ashwell6 has related three cases in which he examined the ovaria of 1 Bullet, de FAcadem. Royale de Me"d., Jan., 1843. 2 De la Puberty et de PAge Critique chez la Femme, et sur la Ponte des Mammiferes, &c, Paris, 1844. s On the other hand, a case has been recently published by Mr. Godard, in which it appeared to him, from the phenomena observed after death, that in a first menstrua- tion the sanguineous discharge had preceded, for a long time, the rupture of the ova- rian vesicle; and he expresses the opinion that it alone may constitute the menstrual phenomenon. Comptes Rendus des Seances de la Societe de Biologie, p. 110, Annee 1854. 4 London Medical Gazette, 1843 ; Lond. and Edinb. Monthly Journal of Med., Aug., 1845, or Amer. Journal of Med. Sciences, Oct., 1845, p. 431, and Jan., 1846, p. 185. 0 The same view is maintained by Mr. Kesteven, London Medical Gazette, for Nov., 1849; see, also, Whitehead, On the Causes and Treatment of Abortion and Sterility, Amer. edit., p. 49, Philad., 1848. 6 A Practical Treatise on the Diseases Peculiar to Women, 3d edit., Lond., 1848. 410 GENERATION. women, who had died during the menstrual flow, and in none was there the physical evidence of a maturated or rent Graafian vesicle; and he properly remarks, that it is by observation on the human female alone that the point can be settled. Moreover, it is impor- tant to bear in mind, in connexion with this subject, that although the discharge of ova may, and does, occur independently of sexual inter- course and excitement, M. Coste—as elsewhere remarked—has shown, that sexual intercourse may hasten their discharge, and he draws at- tention to what is observed in animals in the wild and in the domes- ticated state. In the former condition, "incessantly occupied with their own preservation, often exposed to the inclemency of the wea- ther, and unable to procure sufficient nutriment, the functions of the ovaries are executed at rare intervals. But when they are sheltered in our dwellings, and are subjected to all the favourable conditions that domestication procures them, the maturation of ova may become so frequent that, with certain species, the ponte may be almost daily."1 He has satisfactorily shown, also, that the recurrence of the period of heat is amazingly hastened by the presence and efforts of the male; and judiciously concludes:—"If, in birds, shelter, warmth, and nourishment can multiply the periods for the maturation and discharge of ova, and if in the mammalia the same causes, combined with the excitement of the male, are powerful enough to produce the same result, it would not be rational to suppose that the human species, which can be placed at its pleasure under all these conditions, and gathers around it all the benefits of civilization, should be inaccessi- ble to these influences; and, by an inexplicable exception, should remain invariably restricted within the insurmountable limits of the menstrual periods. Such a supposition would be the more unrea- sonable, seeing—as I have already remarked—that woman has, and the females of the mammalia have not, the privilege of a permanent aptitude for sexual intercourse; and, consequently, the activity which the male influence can impress on the functions of her ovaries ought to be more intense than in the mammalia, in which such influence is much less direct, as it is reduced to simple efforts, that are resisted by the female." The essential condition of menstruation would seem to be increased turgescence of the vessels of the uterus, and hypertrophy of the lining membrane, the morphology of which is analogous to that of the de- cidua of pregnancy. M. Coste2 affirms, that he is possessed of twenty wombs of persons who were suicides, or died of some violent death, in which there was hypertrophy of the lining membrane of the uterus, the result of erethism; but in no case were there the floating villosi- ties mentioned by Baer and E. Weber, or the pseudo-membranous exudation which may remain for at least two weeks described by almost all physiologists. It has been much urged of late, as it was formerly, that there is a striking analogy between menstruation, and the rut or period of heat in animals; and so far as regards the maturation of ova, and the peri- odical secretion from the genital organs in the two conditions there 1 Op. cit., p. 224. 2 Op. cit., p. 210. MENSTRUATION. 411 may be ground for the analogy; but in other respects it is forced, and unsatisfactorily supported. Heat in animals means " venereal heat"— ardor venereus—and at that time only does'the female admit the male ; whilst the human female receives him at all times. It has been at- tempted, indeed, to show, that the human female, during menstruation, has the same increase of venereal ardour, and that the capability for impregnation is at this time at its acme; but this is not in accordance with exact observation. That the aptitude is greater immediately after menstruation has been maintained since the time of Hippocrates.1 It has been an old remark, too, that some are only capable of conception during the flow of the catamenia.2 Miiller,3 Burdach,4 and others, have denied the greater sexual feeling during the flow; and the author, after careful inquiry, has met with nothing to confirm it. After the menstrual period, it can be understood, that more feeling may exist, owing to sexual intercourse having been for a time interrupted; yet it would appear, that impreg- nation frequently occurs immediately before the last catamenial dis- charge. " The fact," says Dr. Carpenter,5 " that conception often takes place before the last appearance of the catamenia (and not after it, as commonly imagined), is one well known to practical men." He is one of those who think " there is good reason to believe, that in women the sexual feeling becomes stronger at that epoch [the menstrual]; and "it is quite certain," he says, that "there is a greater aptitude for con- ception immediately before-and after menstruation than there is at any intermediate period." It would be strange, however, if the period of greatest aptitude for conception should be the one at which there is, anfl always has been, a repugnance to sexual union on the part of both sexes. Bischoff and Mr. Girdwood,6 consider this repugnance as the result of habit, and the natural delicacy of the sex, rather than of actual disrelish ; but this is by no means proved: on the contrary, facts would seem to establish the reverse. As confirmatory of the view, it has been affirmed by M. Raciborski7—who is, by the way, an ardent and enthusiastic observer— that the exceptions to the rule, that conception occurs immediately before, or immediately after, or during menstruation, are not more than six or seven per cent.; and that "of fifteen women, who specified accu- rately the period of their latest menstruation, as well as the dates of the connubial act, five conceived from coitus taking place from two to four days previous to the period at which the catamenial discharge was due; in seven, conception was dated from coitus occurring two or three days after menstruation; in two, it took place at the actual period of the catamenia; and in only one so long as ten days after." Even in 1 De NaturaPuer., cap. iii.; Pliny, Hist. Nat., sect. vii. lib. 18 ; Galen, De Semine, lib. i. 2 Aristotle, Hist. Animal, lib. vii. cap. ii., Ambrose Pare, De Homin. Gener. liber. See, on all this subject, Prof. Litzmann, art. Schwangerschaft, Wagner's Handworter- buch der Physiologie, 13te Lieferung, S. 47, Braunschweig, 1846, and Coste, op. cit., p. 190. 3 Physiology, by Baly, p. 1482. * Die Physiologie als Erfahrungswissenschaft, i. 250, 2te Auflage, Leipz., 1835. 6 Op. cit. 6 London Lancet, Dec. 7 and 14, 1844. 7 London Lancet, Jan. 28,1843, and in op. cit. 412 GENERATION. the exceptional case—we are told—the catamenia made their appear- ance shortly after the coitus, which took place at about the middle of the interval between the two regular periods. These statements may be taken for what they are worth. Even if the facts were accurately observed, of which doubt may be entertained, they are numerically insufficient to enable any positive conclusions to be drawn: certainly, we are not sanctioned in inferring, that excepting within a short period before and after menstruation, the female is not likely to conceive, when—as before remarked—it has been sufficiently proved, that she is throwing off from the ovary infecund ova at other periods than the menstrual, and when there are unquestioned examples of fecundation resulting from a single coitus at an advanced stage of the intermenstrual period. All that we are perhaps justified in admit- ting, from recent observations, is, that there is a connexion between menstruation and the condition of the ovaries, regarding which, indeed, there ought to have been no doubt, as in a celebrated case of removal of both ovaries by Mr. Pott, menstruation entirely disappeared, al- though, previous to the removal, puberty existed, and the function had been well executed; and in disorganization of both ovaries the same thing has been observed j1—that ova are at this time, as at others, ma- turated and discharged into the Fallopian tubes;—and that changes occur in the lining of the uterus accompanied by a peculiar discharge; —the ovarian and uterine changes being simultaneous, and perhaps the latter being consequent on the former; but we have not approached, in the slightest degree, to a knowledge of the purpose served by the periodical catamenial secretion. If the periodical discharge of ova be menstruation, why is it, that the catamenial flow does not always accompany the maturation and discharge of ova ? The bearing of these views on impregnation and the formation of corpora lutea will be given hereafter. The age, at which menstruation commences, varies in individuals and climates. It has been esteemed a general law, that the warmer the climate, the earlier the discharge takes place, and the sooner it ceases; but there is reason for doubting the correctness of this preva- lent belief. With us, the most common period of commencement is from thirteen to seventeen years. Mahomet is said to have consum- mated his marriage with one of his wives, " when she was full eight years old."2 Of 450 cases, observed at the Manchester Lying-in Hos- pital, in England,3 menstruation commenced in the eleventh year in 10 ; in the twelfth in 19 ; in the thirteenth in 53 ; in the fourteenth in 85 ; in the fifteenth in 97 ; in the sixteenth in 76; in the seventeenth in 57; in the eighteenth in 26; in the nineteenth in 23; and in the twentieth in 4. Menstruation commonly ceases in the temperate /one at from forty to fifty years. These estimates are, however, liable to many exceptions, dependent upon individual differences. In rare cases, the catamenia have appeared at a very early age, even in child- hood ; and again, the menses with powers of fecundity have continued, 1 Ashwell, A Practical Treatise on the Diseases peculiar to Women: Amer. edit, by Dr. Goddard, p. 49, Philad., 1845. 2 Prideaux, Life of Mahomet, p. 30, London, 1718. 3 Roberton, op. citat. MENSTRUATION. 413 i in particular instances, beyond the ages that have been specified: in some of these protracted cases the catamenia have been regular; in others, the discharge, after a long'suppression, has returned. Of 77 individuals, they ceased in 1 at the age of 35; in 4 at 40; in 1 at 42; in 1 at 43; in 3 at 44; in 4 at 45; in 3 at 47; in 10 at 48; in 7 at 49; in 26 at 50; in 2 at 51; in 7 at 52 ; in 2 at 53; in 2 at 54; in 1 at 57; in 2 at 60; and in one at 70. Of 10,000 pregnant females, registered at the Manchester Hospital, 436 were upwards of 40 years of age; 397 from 40 to 45; 13 in their 47th year; 8 in their 48th; 6 in their 49th; 9 in their 50th; 1 in her 52d; 1 in her 53d; and 1 in her 54th. Mr. Roberton asserts, that as far as he could ascertain,— and especially in the three cases above 50 years of age,—the catamenia continued up to the period of conception. The following table, founded on the results of 2352 cases, has been published by M. Briere de Boismont.1 It will be seen, that by far the greatest number of women begin to menstruate during the 14th or loth year. Paris, Paris, Lyons, Marseilles, Manchester, Giittingen, Age. 1200 cases by 85 cases by 432 cases by 68 cases by 450 cases by 137 cases by Meniers. Marc D'ES-pine. P6trequin. Marc D'Es-pine. Roberton. Osiander. 5 1 0 0 0 0 0 7 1 0 0 0 0 0 8 2 0 0 0 0 0 9 10 1 0 0 0 0 10 29 0 5 0 0 0 11 93 3 14 6 10 0 12 105 14 26 10 19 3 13 132 6 47 13 53 8 14 194 18 50 9 85 21 15 190 14 70 16 97 32 16 141 7 79 8 76 24 17 127 6 58 4 57 11 18 90 5 38 2 26 18 19 35 8 21 0 23 10 20 30 3 9 0 4 8 21 8 0 5 0 0 1 22 8 0 1 0 0 0 23 4 0 0 0 0 1 24 0 0 3 0 0 0 Dr. Guy2 has furnished some valuable statistics in regard to the period at which the function commences and ceases amongst females in Eng- land. From observations on 1500 cases, it appeared, that the greatest number first menstruated at the age of 15; the 14th year came next in order; then the 16th; whilst the number at 13 and 17, at 12 and 18, and at 11 and 19, approximated very closely to each other. Before the 11th, and after the 19th year, the numbers were very small. In more than half the cases, menstruation made its first appearance at 14, 15, and 16 years of age. The earliest period was 8, and the latest 25. In regard to the period at which it ceases, he deduced from the results of 400 cases, that independently of disease, this might be at any period from the 27th to the 57th year. In the majority of cases it occurred 1 De la Menstruation, &c, Paris, 1842. 2 Medical Times, Aug. 9, 1845. 414 GENERATION. » between 40 and 50 years,—the number from 45 to 50 being greater than that from 40 to 45 years. Mr. Roberton1 has attempted,"and successfully, to show, that the age of puberty is about as early in the cold, as in the tropical regions of the earth; and, that were marriages to take place in England at as juve- nile an age as they do in Hindostan, instances of very early fecundity would be as common in England as they are in that country. He is of opinion, that early marriage and early intercourse between the sexes where found prevailing generally, "are to be attributed, not to any peculiar precocity, but to a moral and political degradation, exhibited in ill laws and customs, the enslavement more or less of the women, ignorance of letters, and impure or debasing systems of religion." He has also shown, from statistical evidence, that menstruation does not occur more early in the negress than in the white female; Dr. Vaigas, of Caraccas, indeed, in a letter to Professor Meigs, of Philadelphia, affirms, that precocious menstruation is more common in the white than in the coloured.2 It would seem, too, that when accurate investigations have been made, there is no striking difference between the age of puberty in the Esquimaux and in the women of Great Britain and this country. It is neither later owing to the rigour of the climate, nor earlier owing to race. Of 16 Esquimaux women, in regard to whom data on this subject were furnished to Air. Roberton,3 none menstruated under the age of 14; but, on the other hand, half the 16 Esquimaux menstruated under 16 years of age; whilst in corresponding data in regard to English women furnished by these observers, there was but one. In the statement sent to Parliament by Bartholomew Mosse, when endeavouring to procure a grant for the Dublin Lying-in Hospital, he mentions, that 84 of the women delivered under his care were between the ages of 41 and 54; 4 of these were in their 51st year, and 1 in her 54th. A relation of Haller had two sons after her 50th year; and children are said to have been born even after the mother had attained the age of 60. A woman at Whitehall, New York, was delivered of a child at the age of 64.4 Holdefreund relates the case of a female, in whom menstruation continued till the age of 71; Bourgeois till the age of 80; and Hagendorn till 90; it is probable, however, that these were not cases of true menstruation, but perhaps of irregularly periodical discharges of blood from the uterus or vagina. On the other hand, it may be remarked, that in the year 1828, a lady was a visitor at Ballston Springs, who was a grandmother, although only 28 years of age.4 A case is, also, recorded of a female, who menstruated when one year old, and was pregnant at a little over 9. On the 20th of April, 1834, being 10 years and three days old, she was delivered of a child 1 Edinburgh Med. and Surg. Journal, Oct., 1832, July, 1842, and July, 1845, p. 156; and London Med. Gazette, July 21, 1843. 2 A Treatise on the Diseases and Special Hygiene of Females, by Colombat de l'lsere, translated by Dr. Meigs, p. 21, Philad., 1845. 3 Edinburgh Medical and Surgical Journal; cited in London and Edinburgh Monthly Journal of Medical Science, March, 1845. p. 232. ' T. D. Mitchell, Western Lancet, Nov., 184tf p. 277. 5 Mitchell, op. cit., p. 276. MENSTRUATION. 415 weighing 7f lbs.1 Sir George Simpson2 states, that during his visit to Woahoo, a woman, twelve years of age, was living, "who had already presented to an English husband three thriving pledges of connubial love;" and the case of a young girl has been recorded by Mr. John Smith,3* who began to menstruate when ten years and six months old, and was delivered of a child at 11 years and seven months.4 As a general rule, the appearance of the menses denotes the capa- bility of being impregnated, and their cessation the loss of such capa- bility, yet, as already remarked, females have become mothers without ever having menstruated. Fodere5 attended a woman, who had men- struated but once—in her 17th year,—although 35 years of age, healthy, and the mother of five children. Morgagni instances a mother and daughter, both of whom were mothers before they menstruated. Sir E. Home6 mentions the case of a young woman, who was married before she was seventeen, and, having never menstruated, became pregnant: four months after her delivery, she became pregnant again; and four months after the second delivery, she was a Jhird time pregnant, but miscarried: after this she menstruated for the first time, and continued to do so for several periods, when she again became pregnant; and Mr. Harrison,7 at a meeting of the Westminster Medical Society, remarked, that he knew an instance in which the mother of a large family had never menstruated;—yet Dr. Dewees8 and Dr. Campbell9 assert, that there is not a properly attested instance on record of a female con- ceiving previous to the establishment of the catamenia: the latter gentleman admits, however, that when an individual has once been impregnated, she may conceive again several times in succession, with- out any recurrence of the catamenia between these different concep- tions,—because he has known a case of this kind, but not of the other! During the existence of menstruation, the system of the female is more irritable than at other times; so that all exposure to sudden and irregular checks of transpiration should be avoided, as well as every kind of mental and corporeal agitation, otherwise the process may be impeded, or hysterical and other troublesome affections be excited. The sacred volume exhibits the feeling entertained towards the female, whilst performing this natural function. Not only was she regarded "unclean" in antiquity: she was looked upon, as Dr. Elliotson has remarked,10 to be mysteriously deleterious. In the time of Pliny,11 a menstruating female was considered to blight corn, destroy grafts and hives of bees, dry up fields of corn, cause iron and copper to rust and smell, drive dogs mad, &c, &c; and it is firmly believed by many, that meat will not take salt if the process be conducted by one so circum- 1 Transylvania Med. Journ., vii. 417 ; cited by Mitchell, op. cit. 2 An Overland Journey round the World, Amer. edit., Part 2, p. 61, Philad., 1847. 3 Lond. Med. Gaz., Nov. 3, 1848. * Other cases are given in Taylor, Medical Jurisprudence, 3d Amer. from 4th Lond. edit., p. 440, Philad., 1853. 5 Medecine Legale, i. 393, Paris, 1813. 8 Philosoph. Transact., cvii. 258 ; and Lect. on Comp. Anatomy, iii. 298. 7 London Lancet, Jan. 19, 1839, p. 619. 8 Compend. System of Midwifery, 8th edit., Philad., 1836. 9 Introduction to the Study of Midwifery, Edin., 1833. 10 Elliotson's Blumenbach, p. 465; Lond., 1828. " Histor. Natural., xxvii. 416 GENERATION. stanced. La Motte1 had implicit belief in this opinion, and carried the absurdity so far as to assert, that red-haired women are worse thau others in this respect; and he gives an anecdote of a red-haired servant of his who spoiled some choice wine, as he was about to sit down to enjoy it. He asserts positively, that the instant she touched the bottles the wine was converted into vinegar,—much to the annoyance of him- self and guests. The temperature of the vagina does not appear to be affected by menstruation or pregnancy.2 c. Sexual Ambiguity. The sexual characteristics, in the human species, are widely sepa- rate ; and two perfect sexes are never united in the same individual. Yet such an unnatural union has been supposed to exist; from the fabulous son of 'Ep^j and A^poSt^,—Mercury and Venus,—to his less dignified representative of modern times:— p " Nee foemina dici, Nee puer ut possent, neutrumque et utrumque videntur."—Ovid.3 We have already remarked, that in the lower animals, and in plants, such hermaphrodism is common; but, in the upper classes, and espe- cially in man, a formation that gives to an individual the attributes of both sexes has never been witnessed. Monstrous formations are occa- sionally met with; but if careful examination be made, it can usually be determined to what sex they belong. Cases, however, occur, in which it is difficult to decide, although we may readily pronounce, that the being is totally incapable of the function of reproduction. The generality of cases are produced by unusual developement of the clitoris in the female, or by a cleft scrotum "in the male. Only two instances of the kind have fallen under the observation of the author, both of which were females, as they usually are. One of these has been described by the late Professor Beclard, of Paris, whose details we borrow.4 Marie-Madeleine Lefort, aged sixteen years, seemed to belong to the male sex, if attention were paid merely to the proportions of the trunk, limbs, shoulders, and pelvis; the conformation and dimensions of the pelvis; the size of the larynx; the tone of the voice; the developement of the hair; and the form of the urethra, which extended beyond the symphysis pubis. An attentive examination, however, of the genital organs showed, that she was of the female sex. The mons veneris was round, and covered with hair. Below the symphysis pubis was a clitoris, resembling a penis in shape, twenty-seven millimetres or about an inch long, in the state of flaccidity; and susceptible of slight elongation during erection ; having an imperforate glans, hollowed beneath by a duct or channel, at the inferior part of which were five small holes situate regularly on the median line. Beneath and behind the clitoris, 1 Traite des Accouchemens, p. 57. 2 Fricke, Zeitschrift fiir die gesammte Medicin, Nov., 1838. 3 " Both bodies in a single body mix, A single body with a double sex."—Addison. 4 Marc, art. Hermaphrodite, in Diet, des Sciences Medicales, xxi. 98, Paris, 1817. SEXUAL AMBIGUITY. 417 a vulva existed, with two narrow, short and thin labia furnished with hair, devoid of anything like testicles, and extending to within ten lines of the anus. Between the labia was a superficial cleft, pressure upon which communicated a vague sensation of a void space in front of the anus. At the root of the clitoris was a round aperture, through which a catheter could not be passed into the bladder. It could be readily introduced, however, towards the anus, in a direction parallel to the perineum. When the catheter was passed a little backwards and upwards to the depth of eight or ten centimetres, it was arrested by a sensible obstacle; but no urine flowed through it. It seemed to be in the vagina. At the part where the vagina stopped, a substance could be distinguished through the parietes of the rectum, which seemed to be the body of the uterus. Nowhere could testicles be discovered. She had menstruated from the age of eight years; the blood issuing in a half coagulated state through the aperture at the root of the clitoris. She experienced, too, manifest inclination for the male, and a slight operation only would probably have been necessary to divide the apron, which closed the vulva from the clitoris to the posterior commissure of the labia. The urethra extended, in this case, for some distance beneath the clitoris, as in the penis; and from all the circumstances, M. Bcclard concluded, that the person subjected to the examination of the Societe de Medecine of Paris was a female; that she possessed several of the essential organs of the female,—the uterus and vagina,—whilst she had only the secondary characters of the male—as the proportions of the trunk and limbs, shoulders and pelvis; the conformation and dimensions of the pelvis; the size of the larynx; tone of the voice; developement of the hair; the urethra extending beyond the symphysis pubis, &c. In the year 1818, a person was exhibited in London, who had a sin- gular union of the apparent characteristics of both sexes. The coun- tenance resembled that of the male, and there was a beard, but it was scanty. The shape, however, of the body and limbs was that of the female. The students of the Anatomical Theatre of Great Blenheim Street, London, of whom the author was one, offered her a certain sum, provided she would permit the sexual organs to be inspected by the veteran head of the school—Mr. Brookes: to this she consented.. She was, accordingly, exposed before the class; and her most striking pecu- liarities exhibited. The clitoris was large, but not perforate. Mr. Brookes, desirous of trying an experimentum crucis, passed a catheter into the vagina, and attempted to introduce another into the urethra; but fearing discovery, and finding that the mystery of her condition was on the point of being unveiled, she started up and defeated the experiment. No doubt existed in the mind of Mr. Brookes, that there were two distinct canals,—one forming the vagina; the other the ure- thra,—and that she was, consequently, female. One of the most complete cases of admixture of the sexes was de- scribed by Rudolphi before the Academy of Sciences of Berlin, at the sitting of October 22, 1825.1 It was met with in the body of a child, which died, it was said, seven days after birth; but the developement 1 American Journal of the Medical Sciences, p. 499, Feb., 1832. VOL. II.—27 418 GENERATION. of parts led to the supposition, that it was three months old. The penis was divided inferiorly; the right side of the scrotum contained a testicle; the left was small and empty. There was a uterus, which communicated at its superior and left portion with a Fallopian tube behind which was an ovary destitute of its ligament. On the' right side, there was neither Fallopian tube, nor ovary, nor ligament, but a true testicle, from the epididymis of which arose a vas deferens. Below the uterus was a hard, flattened ovoid body, which, when divided, ex- hibited a cavity with thick parietes. The uterus terminated above in the parietes of this body, but without penetrating its cavity. At its inferior part was a true vagina, which ended in a cul-de-sac. The urethra opened into the bladder, which was perfect; and the anus, rectum, and other organs were formed naturally. Rudolphi considered the ovoid body, situate beneath the uterus, to be the prostate, and vesiculae seminales, in a rudimental state. A curious case of doubtful sex was seen by Dr. Pue, of Baltimore. It occurred in a negro, who had the appearance of a woman, and passed for such. On examination, at the request of her owner, Dr. Pue found no signs of female organs of generation. There was a penis of some developement—the size of a boy's 12 or 14 years old. The glans was well formed, but the urethra did not terminate at the extremity of the organ. It opened at the frsenum. There was some appearance of scrotum, but no testes were perceptible. Menstruation took place regularly, but with great pain, the fluid passing through the urethra. During this period, the breasts—which were natural, and of the size of a girl's of 14—became tender and swollen, and she had sexual desire at this time only. The pubes was well covered with hair. Dr. Pue's impression was, that her inclinations were for the male. A similar case has been described by Dr. S. II. Harris, of Clarksville, Virginia.1 Cases like the above,—and we have such on the authority of Baillie, Verdier, Giraud, Ackermann, Handy, Sir E. Home, Pinel, Maret, Sue, Bouillaud, and others,—have led to the belief, that hermaphrodism is possible. Such is the opinion of Tiedemann, Meckel, and others. The varieties of these sexual vagaries are extremely numerous; and occa- sionally form the subject of medico-legal inquiry. A singular case, in which a question of civil rights was involved, has been detailed by Dr. William James Barry.2 At a warmly contested election in Connecticut, in the spring of 1843, a person named Suydam was brought forward as a voter, who was challenged by the opposite party, on the ground that he was more female than male, and that he partook of the attri- butes of both sexes. On examining him, Dr. Barry found the mons veneris covered with hair in the usual way; there was an imperforate penis, subject to erection, about two inches and a half long. It had a well formed glans, with a depression in the usual seat of the orifice of the urethra, and a well defined prepuce and foramen. The scrotum was not more than half the usual size, and not pendulous. In it, on the right side, was a testicle, of the size of a common filbert, with a spermatic cord. At the root of the corpora cavernosa in the perineum, ' American Journal of the Medical Sciences, for July, 1847, p. 121. 2 New York Journal of Medicine, &c, Jan., 1847. SEXUAL AMBIGUITY. 419 there was an aperture, through which the urine was discharged, large enough to permit the introduction of an ordinary sized catheter. From these appearances, Dr. Barry gave it as his opinion, that the person was a male citizen, and, consequently, entitled to vote. This decision was contested by Dr. Ticknor, who, however, after an examination, suggested by Dr. Barry, admitted, that Suydam was a male. He was accordingly allowed to vote; and the party ticket was carried by a majority of one. A few days after the election, Dr. Barry was informed, that Suydam had catamenia; and testimony was afforded, that he menstruated as regularly, but not as profusely, as most women. Drs. Barry and Tick- nor now examined him together, with the following results. His height was five feet two inches; hair light coloured; complexion fair; chin beardless; temperament decidedly sanguineous; shoulders narrow; hips broad; and in short the figure was in all respects that of a female. The mammas were well developed, with nipples and areolae. On passing a female catheter into the opening through which the urine, as well as a monthly sanguineous flow, was discharged, the catheter, in place of entering the bladder, passed into a canal, similar to the vagina, three or four inches deep, in which the instrument had considerable play. Suydam stated, that he had erotic desires for the male sex, and his tastes and bodily powers resembled those of the female. It appeared, too, from proper testimony, that the aperture, through which the urine was discharged, was made by the accoucheur at the time of birth. Drs. Barry and Ticknor had, therefore, to renounce their previously ex- pressed conviction that Suydam belonged to the male sex. The case of an ourang-outang, described by Dr. Harlan,1 affords as near an approach to a complete union of the sexes in the same indi- vidual as has been recorded. It had ovaries, Fallopian tubes, uterus, and vagina, and also testes, epididymis, vasa deferentia, and a highly erectile penis. Dr. Carpenter2 states, that it is not certain, that the co-existence of testes and ovaria on the same side has ever been ob- served in the human species; yet a case has been described by Prof. Mayer,3 of Bonn, in which the mixed attributes of male and female were well marked. On the one hand, there was a testicle slightly atrophied, a penis, and a prostate gland; on the other, a vagina and uterus with its Fallopian tubes; and, on the left side, a body analo- gous to an ovary. Dr. Blackman,J also, has recorded a singular case of admixture of sexes, which occurred to Dr. Ackley, of the Cleveland Medical College. It occurred in a person of large stature; external conformation, with the exception of the hips, male; beard moderate; penis large; scrotum of natural appearance, but empty; habits solitary, and disliking women; menstruation per penem monthly, attended with much suffering; and during one of these periods death occurred from cerebral congestion. The body was examined by Prof. Ackley. B'ig. 430 will convey a good idea of the condition of the organs. h 1 Medical and Physical Researches, p. 22, Philad., 1835. 2 Principles of Human Physiology, Amer. edit., p. 803, Philad., 1855. See, also, on this subject, Prof. Simpson, art. Hermaphroditism, in Cyclop, of Anat. and Phy- siol., ii. 684, London, 1839. 3 Gazette Medicate de Paris, Sept. 24, 1836, and Philadelphia Med. Examiner, April 10, 1841, p. 232. * Amer. Journal of the Medical Sciences. July, 1853, p. 66. 420 GENERATION. The vagina opened into the neck of the bladder, and thus communi- cated with the urethra. Its inner surface was reddened, and the Fig. 430. 1. Male organ. 2. Scrotum, empty. 3. Prostate gland. 4. Vagina. 5. Os uteri. 6. Uterus. 7. Blad- der. 8 and 9. Right and left Fallopian tubes. 10 and 11. Right and left testes. 12 and 13. Right and left ovaries. 14. Rectum. 15 and 16. Right and left vas deferens. cavity contained menstrual blood. The Fallopian tubes were per- vious, and the excretory ducts of the testes perfect. " Here, then," says Dr. Blackman, " we have an example of a monster with a testicle and ovary on each side; and with a prostate gland and uterus, the co-exist- ence of which in the same being has been so flatly denied." Monstrous productions, with a mixture of the male and female or- gans, seem to occur in neat cattle, and have been called free-martins. When a cow brings forth twin calves, one a male and the other appa- rently a female, the former always grows up to be a perfect bull; but the latter appears destitute of all sexual functions, and never propa- gates. This is the free-martin. It was the opinion of Mr. Hunter, that SEXUAL AMBIGUITY. 421 it never exhibits sexual propensities; but this has been controverted by Mr. Alluatt.1 A clergyman of great respectability informed him, that he had bred a free-martin upon his estate, which had not only shown a natural desire for the male, but had admitted him—of course, ineffectually. Mr. Allnatt farther remarks, that he had seen, the day before, working in harness, a true, apparently female, adult free-mar- tin, which occasionally manifested its male propensities in an intelli- gible manner. When the cows amongst which this free-martin is kept, exhibit their inclination for the male, the creature—unlike the spayed heifer or common ox—is peculiarly on the alert, and has been observed to leap them like the entire male. A gentleman of Mr. All- natt's neighbourhood had a true free-martin, which had received the bull several times, but had never propagated. After death the animal was examined. Scarcely a vestige of uterus could be discovered. From Mr. Hunter's observations'3 it would seem, that in all the instances of free-martins, examined by him, no one had the complete organs of the male and female, but partly the one and partly the other; and, in all, the ovaria and testicles were too imperfect to perform their functions. In noticing this phenomenon, Sir Everard Home3 remarks, that it may account for twins being most commonly of the same sex: "and when they are of different sexes," he adds, " it leads to inquire, whether the female, when grown up, has not less of the true female character than other women, and is incapable of having children." " It is curious," says Sir Everard, " and in some measure to the purpose, that, in some countries, nurses and mid wives have a prejudice, that such twins sel- dom breed." Dr. Burns, too,4 states it to be a popular opinion, and he does not know any instance to discountenance it, that if twins be of different sexes the female is sterile. These remarks are singularly unfortunate, and ought not to have been hastily hazarded, seeing that a slight inquiry would have exhibited, that there is no analogy be- tween the free-martin and the females in question; and, more espe- cially, as the suggestion accords with a popular prejudice, highly inju- rious to the prospects, and painful to the feelings of all who are thus circumstanced. In the London Medical Repository,4 Mr. Cribb, of Cambridge, England, has properly observed, that the external charac- ters and anatomical conformation of the free-martin are totally unlike those of the human female. In external appearance, it differs con- siderably from the perfectly formed cow;—the head and neck, in par- ticular, bearing a striking resemblance to those of the bull. More- over, it is not true, that the free-martin cows never breed: Professor Simpson,6 of Edinburgh, has referred to cases in which they were fecund. Mr. Cribb has, however, brought forward most decisive evi- dence in favour of the fallacy of the popular prejudice, by the history ' of seven cases, which are of themselves sufficient to put the matter for ever at rest. Of these seven, which are all that he had ever known, of v 1 London Medical Gazette for July 2d, 1836. 2 Animal fficonomy, edit, by Mr. Owen, Amer. edit., p. 70, Philad., 1840. 8 Philosoph. Transactions for 1799 ; and Lectures on Comparative Anatomy, iii. 311, London, 1823. 4 Principles of Midwifery, edit, of 1843. s Sept. 1823, and Ibid., 1827. 8 Edinb. Med. and Surg. Journ., Jan., 1844, p. 109, and Obstetric Memoirs and Con- tributions, p. 314, Edinb., 1855. 422 GENERATION. women, born under the circumstances in question, having been mar- ried,—six had children. The fullest and most satisfactory essay on this subject is, however, the one already referred to by Professor Simp. son. By uniting together all the various cases, which he could collect he found that he possessed the married history of 123 females born co-twins with males. The results, so far as they refer to this subject, are as follows: of 123, 112 had families, and 11 no issue, although married for several years. In other words, the marriages of females, born under such circumstances, were infecund in the proportion of 1 in 10. From other investigations he deduced, that this proportion does not exceed the degree of unproductiveness of marriages in the general community; and from the whole of his inquiries he arrives at the following important conclusions. First. That in the human sub- ject, females, born co-twins with males, are, when married, as likely to have children as any other females belonging to the general com- munity. Secondly. That when they are married and become mothers, they are, in respect to the number of their children, as productive as other females; and Thirdly. That the same law of fecundity of the female in opposite-sexed twins seems to hold good amongst all the uniparous domestic animals, with the exception of the cow. It is certainly strange, that this exception should apply to the cow only; and that when she carries twins of the same sex—two males, or two females—they should be in all cases perfectly formed in their sex- ual organization, and both be capable of propagating. The whole series of circumstances, when considered in conjunction with each other—as is well remarked by Professor Simpson—seems to form, in relation to the origin of malformations, one of the strangest and most inexplicable facts to be met with in the study of abnormous develope- ment.1 2. PHYSIOLOGY OF GENERATION. In man and the superior animals, in which each sex is possessed by a distinct individual, it is necessary that there should be a union of the sexes, and that the fecundating fluid of the male should be conveyed within the appropriate organs of the female, in order that, from the con- course of the matters furnished by both sexes, a new individual may result. To this union they are incited by an imperious instinct, esta- blished within them for the preservation of the species, as hunger and thirst are placed within them for the preservation of the individual. This has been termed the desire or instinct of reproduction; and for wise purposes its gratification is attended with the most pleasurable feelings, that man or animals can experience. Prior to the period of •puberty, or whilst the individual is incapable of procreation, this desire does not exist; but it suddenly makes its appearance at puberty; persists 0 vehemently during youth and the adult age, and disappears in advanced life, when procreation becomes again impracticable. It is strikingly exhibited in those animals, in which generation can only be effected at 1 See on the subject of Hermaphrodism, Prof. Simpson, art. Hermaphroditism, in op. cit., Marc, art. Hermaphrodite, op. cit., and J. G. St. Hilaire, Histoire Generate et Par- ticuliere des Anomalies de I'Organisation, ii. 23, Bruxelles, 1837; also, Taylor, Medical Jurisprudence, Amer. edit., by Dr. E. Hartshorne, p. 425, Philad., 1853. COPULATION. 423 particular periods of the year, or whilst they are in heat;—as in the deer, during the rutting season. The views that have been entertained regarding the seat of this instinct—whether in the encephalon or genital organs—are considered under the head of the mental and moral manifestations. It is there stated, that MM. Cabanis and Broussais consider, that internal impres- sions proceed from the genital organs, and form part of the psychology of the individual; and that Gall assigns an encephalic organ—the cere- bellum—for their production, ranking the instinct of reproduction amongst the primary faculties of the mind,—with what degree of truth, is there investigated. In many cases, the desire is produced through the agency of vision ; when the brain must necessarily be first excited, and, through its influence, the generative apparatus. Its immediate cause has been ascribed by some, to the presence of sperm, in the requisite quantity, in the vesicula? seminales; but in answer to this, it is urged, that eunuchs under the circumstances above mentioned, and females, in whom there is no spermatic secretion, have the desire. The fact is, we have no more precise knowledge of the nature of this in- stinct, than we have of any of the sensations or moral faculties. We know, however, that it exhibits itself in various degrees of intensitv, and occasionally assumes an opposite character—constituting anaphro- disia. a. Copulation. In the union of the sexes, the part performed by the male is the in- troduction of the penis,—the organ for the projection of the sperm towards the uterus,—and the excretion of that fluid during its intro- duction. In the flaccid state of the organ penetration is impractica- ble ; it is first of all necessary, that under the excitement of venereal desire the organ should attain a necessary degree of rigidity, which is termed erection. In this state it becomes enlarged, and raised towards the abdomen; its arteries beat forcibly; the veins are tumid; the skin is more coloured, and the heat augmented. It becomes also of a trian- gular shape, and these changes are indicated by an indescribable feel- ing of pleasure. Erection is not dependent upon volition. At times, it manifests itself against the will; at others refuses to obey it; yet it requires, apparently, the constant excitement of the encephalic organ concerned in its production,—the slightest distraction of the mind put- ting an end to it. The modest and retiring spouse is, at times, unable to consummate the marriage for nights, perhaps weeks; yet, he is only temporarily impotent; for the inclination and consequent erection supervene sooner or later. Pills of crumb of bread, and a recom- mendation to the individual not to approach his wife for a fortnight, whatever may be his desire, have, in almost all cases, removed the im- potence. The state of erection is not long maintained, except under unusual excitement;—the organ soon returning to its ordinary condition of flaccidity. Its cause is a congestion of blood in the erectile tissue of the corpora cavernosa, urethra, and glans. Swammerdam and De Graaf cut off the penis of a dog during erection, and found the tissue gorged with blood, and that the organ returned to its flaccid condition 424 GENERATION. as the blood flowed from it. The same fact, according to M. Adelon,1 has been observed in the human subject, when erection has continued till after death. The author's late friend, Mr. Callaway,2 of Guy's Hospital, London, has described the case of an individual, who, in a state of inebriation, had communication three times with his wife the same night, without the consequent collapse succeeding, although emis- sion ensued each time. This state persisted for sixteen days, notwith- standing the use of appropriate means ; at this time, an opening was made with a lancet into the left crus of the penis, below the scrotum; when a large quantity of dark, grumous blood, with numerous small coagula, escaped. By pressing the penis, the corpora cavernosa were immediately emptied, and each side became flaccid,—the communication by the pecten or septum penis permitting the discharge of the contents of both corpora by the incision. After recovery, the person remained quite impotent, the organ being incapable of erection,—probably owing, as Mr. Callaway suggests, to the deposition of coagulable lymph in the cells of the corpora cavernosa preventing the admission of blood, and the consequent distension of the organ. Artificial erection can, like- wise, be induced in the dead body by injections, so that but little doubt need exist, that the enlargement and rigidity of the penis during erec- tion are caused by the larger quantity of blood sent into it. The dif- ficulty has been to account for this increased flow. The older writers ascribed it to the compression of the internal pudic vein against the symphysis pubis, owing to the organ being raised towards the abdomen by the ischio-cavernosi muscles; and as the cavernous vein empties its blood into the internal pudic, stagnation of blood in the corpora caver- nosa ought necessarily to result from such compression, and consequent distension of the organ; whilst the cavernous arteries, being firmer, could not yield to the compression, and would, therefore, continue to convey blood to the penis. It is obvious, however, that here,—as in every case, where the erectile tissue is concerned,—the congestion must be of an active kind; the beating of the arteries and the coloration of the organ indicate this; and, besides, compression of the pudic vein cannot precede erection; it must, if it occurs at all, be regarded rather as a consequence of erection than as its cause. The case of the nipple of the female affords us an instance of erectility, where no compression can be invoked, and where the distension must be caused by augmented flow of blood by the arteries. If the nipple be handled, particularly whilst she is under voluptuous excitement, it enlarges, and becomes rigid, or is in a true state of erection. The correct opinion seems to be, that irritation of this erectile tissue is the first link in the chain of phenomena constituting erection. The feeling of pleasure is certainly experienced there, prior to, and during erection; and this irritation, like every other, solicits an increased flow of blood into the erectile tissue, which, by organization, is capable of considerable distension. The erectile tissues of the corpora cavernosa, corpus spongiosum ure- thral, and glans, are concerned in the process; but in what precise manner physiologists are not entirely agreed. Some have supposed, 1 Physiologie de l'Homme, edit, citat., iv. 57. 2 London Medical Repository, for April, 1824. COPULATION. 425 that the blood is effused into the cells, and is consequently out of the vessels. Another view, supported by certain eminent anatomists and physiologists, is, that the blood simply accumulates in the venous plexuses of the corpora cavernosa. Such seems to have been the opinion of Tiedemann, Stieglitz, and J. Miiller,1 and of Cuvier, Chaus- sier, and Be'clard, from their injections; and the rapidity, with which erection disappears, favours the notion. The discovery of the helicine arteries of the penis by Professor Miiller, described at page 577, has led to the inference that the peculiar arrangement may be concerned in the function in question, but in what manner the circulation in the male organ, or its erection, is modified by them has not been deter- mined; Valentin, indeed,—as we have seen,—denies their existence. It has been asked again, whether this accumulation of blood be, as we have remarked, an increased afflux by the arteries, or a diminished action of the veins; or these two states combined. The last opinion is probably the most correct. The arteries first respond to the appeal; the organ is, at the same time, raised by the appropriate muscles; its tissue becofnes distended; the plexus of veins turgid, and the return of blood impeded. In this way, the organ acquires the rigidity necessary for penetrating the parts of the female. The friction, which then occurs, keeps up the voluptuous excitement, and the state of erection. This excitement is extended to the whole generative system; the secre- tion of the testicles is augmented; the sperm arrives in greater quan- tity in the vesiculae seminales; the testicles are drawn up towards the abdominal ring by the contraction of the dartos and cremaster, so that the vas deferens is rendered shorter, and, in the opinion of some, the sperm filling the excretory ducts of the testicle is in this manner forced mechanically forwards towards the vesicles. When these have attained a certain degree of distension, they contract suddenly and powerfully, and the sperm is projected through the ejaculatory ducts into the urethra. At this period, the pleasurable sensation is at its height. When the sperm reaches the urethra, the canal is in the highest degree of excitement; and the ischio-cavernosi and bulbo- cavernosi muscles, with the transversi perinei, and levatores ani, are thrown into violent contraction; the first two holding the penis straight, and assisting the others in projecting the sperm along the urethra. By the agency of these muscles and of the proper muscular structure in the urethra, the fluid is expelled, not continuously, but in jets, as it seems to be sent into the urethra by the alternate contractions of the vesiculae seminales. These muscular contractions are of a reflex cha- racter, being independent of the will, and incapable of being controlled by any exertion of it. They are induced, as in deglutition, by a* spe- cial excitant,—the sperm in one case; the food in the other.2 The quantity of sperm discharged varies materially according to the circumstances previously mentioned; its average has been estimated at about two drachms. Along with the true sperm, the fluids of the prostate and glands of Cowper are discharged; so as to constitute the 1 Art. Erection, in Encyclop. Worterb. der Medicin. Wissenschaft., xii. 460, Berlin, 1834. 2 For an elaborate inquiry into the physiology of erection, see Beraud, Manuel de Physiologie de l'Homme, pp. 385-400, Paris, 1853. 426 GENERATION. semen as we meet with it. When the emission is accomplished, the penis gradually returns to its ordinary state of flaccidity; and it is usually impracticable, by any effort, to repeat the act without the in- tervention of a certain interval of repose, to enable the due quantity of sperm to collect in the spermatic vessels and vesicles. In some persons, however, the excitability is so great, and the secretion so ready, that little or no interval is required between the first and second acts. A singular case of satyriasis, well observed by Mr. Nor- ris, of London, is recorded by him in the Latin language.1 For two months the man had intercourse with his wife, according to his and her testimony, fifteen times each night, and occasionally twenty times, and always with emission! This comprises the whole of the agency of the male in the function of generation. In man, the emission of sperm is soon effected ; but in certain ani- mals it is a long process. In the dog, which has no vesiculae semi- nales, the penis swells so much, during copulation, that it cannot be withdrawn until the emission of sperm removes the erection11! In the female, during copulation, the clitoris is in the same state of erection as the penis; so is the spongy tissue lining more especially the entrance of the vagina; and it is in these parts, particularly in the clitoris, that pleasure is experienced during sexual desire, and copula- tion. This feeling persists the whole time of coition, and ultimately attains its acme, as in the case of the male, but without any spermatic ejaculation. It is not owing to the contact of the male sperm,—for it frequently occurs before or after emission by the male, but is depend- ent upon some inappreciable modification in the female organs,—in the ovaries or Fallopian tubes, it is supposed by some physiologists. In most—if not in all—cases, an increased discharge suddenly takes place, during the orgasm, from the mucous follicles of the vagina and vulva, but chiefly from the glands of Duverney, the admixture of which with the male sperm is supposed to have some connexion with impregnation, and to be, perhaps, the vehicle for the fecundating prin- ciple of the sperm. After the kind of convulsive excitement into which the female is thrown, a sensation of languor and debility is ex- perienced, as in the male,—but not to the same extent;—and, in con- sequence of no spermatic emission taking place in her, she is capable of a renewal of intercourse more speedily, and can better support its frequent repetition. The comparative degree of voluptuous excitement experienced by the male and female during sexual union has been an oft agitated question. It is of course impracticable to arrive at any positive or even approximative decision. Kobelt2 expresses the opinion, that the great size of the bulbi vestibuli (Fig. 414), and the energetic com- pression they experience from the male organ; and especially the vast amount of nerves concentrated in so small a space, joined to her great general sensibility are ample reasons for inferring that the part of the female in the act is more considerable. 1 Transactions of the Medical Society of London, vol. i. part i. p. 176, Lond., 1^-10. 8 De l'Appareil du Sens Genital des deux Sexes, traduit de l'Allemand, par H. Kaula, D. M., p. 116, Strasbourg & Paris. 1851. FECUNDATION. 427 b. Fecundation. An admixture having, in this manner, been effected between the materials furnished by the male and female,—after a fecundating co- pulation conception or fecundation results, and the rudiments of the new being are instantaneously constituted. The well-known fact, that, after the removal of the testicles, the individual is incapable of pro- creation although the rest of the genital organs may remain entire, is of itself sufficient to show, that the fecundating fluid is the secretion of those organs, and that this fluid is indispensable. Physiologists have not, however, been satisfied with a knowledge of this fact. Spal- lanzani1 examined frogs with great attention, whilst in the act of copulation, both in and out of water; and he observed, that, at the moment when the female deposits her eggs, the male darts a transpa- rent liquid through a tumid point which issues from its anus. This liquid moistens the eggs, and fecundates them. To be certain that it is the fecundating agent, he dressed the male in waxed taffeta breeches; when he found, that fecundation was prevented, and sperm enough was contained in the breeches to be collected. This he took up by means of a camel's-hair pencil, and all the eggs which he touched with it were fecundated. Three grains of the sperm were sufficient to ren- der a pound of water fecundating; and a drop of a solution, which could not contain more than the 2,994,687,500th part of a grain, was enough for the purpose. To diminish the objection, that the frog is too remote in organization from man to admit of any analogical deduc- tion, Spallanzani took a spaniel bitch, which had engendered several times; shut her up some time before the period of heat, and waited until she exhibited evidences of being in that condition, which did not happen until after a fortnight's seclusion. He then injected into the vagina and uterus, by means of a common syringe warmed to 100° of Fahrenheit, nineteen grains of sperm obtained from a dog. Two days afterwards, she ceased to be in heat, and, at the ordinary period, brought forth three young ones, which not only resembled her but the dog from which the sperm had been obtained. This experiment has been repeated by Eossi, of Pisa, and Buffolini, of Cesena, with similar results.2 The success of an analogous experiment on the human spe- cies rests on the authority of John Hunter. He recommended an individual, affected with hypospadias, to inject his sperm through a warm syringe. His wife became pregnant.3 In some experiments on generation, MM. Prevost and Dumas fe- cundated artificially the ova of the frog. Having expressed the fluid from several testicles, and diluted it with water, they placed ova in it. These were observed to become tumid and developed; whilst other ova, placed in common water, merely swelled up, and in a few days became putrid. They observed, moreover, that the mucus, with which the ova are covered in the oviduct,—the part corresponding to the Fallopian tube in the mammalia,—assists in the absorption of the sperm, and in conducting it to the surface of the ovum; and that in 1 Sur la Generation, par Senebier, Genev., 1783. 2 Adelon, Physiologie de l'Homme, iv. 66, Paris, 1829. 3 Sir E. Home, Lect. on Comp. Anat., iii. 315. 428 GENERATION. order to succeed in these artificial fecundations, the sperm must be diluted; if too much concentrated its action is less. They satisfied themselves likewise, that the chief part of the sperm penetrates as far as the ova, as animalcules could be detected moving in the mucus covering their surface, and these animalcules, they conceive, are the active part of the sperm. It is not, however, universally admitted, that positive contact of sperm with the ovum is indispensable to fecun- dation. Some physiologists maintain, that the sperm proceeds no fur- ther than the upper part of the vagina; whence it is absorbed by the vessels of that canal, and conveyed through the circulation to the ovary. This is, however, the most improbable of all the views that have been indulged on this topic; for if such were the fact, impregna- tion ought to be effected as easily by injecting sperm into the blood- vessels,—the female being, at the time, in a state of voluptuous excite- ment. It has been directly overthrown, too, by the experiments of Dr. Blundell1 on the rabbit, who found, that when the communication between the vagina and the uterus was cut off, impregnation could not be accomplished, although the animal admitted the male as often as fifty times, generally at intervals of two or three days or more. Yet it was evident that much of the male fluid had been deposited in the vagina, and absorbed by veins or lymphatics.2 Bischoff3 states, that he has frequently extirpated the uterus in rabbits, leaving the vagina and ovaries with the tubes; and in no case was the animal fecundated after the operation, although it admitted the male freely. Others have presumed, that when the sperm is thrown into the vagina, a halitus or aura—aura seminis—escapes from it, makes its way to the ovary, and impregnates an ovum; whilst others, again, are of opinion, that the sperm is projected into the uterus, and in this cavity undergoes admixture with the germ furnished by the female; and a last class, with more probability in their favour, maintain, that the sperm is thrown into the uterus, whence it passes through the Fal- lopian tube to the ovary, by the fimbriated extremity of the tube embracing at the time the latter organ. Dr. Dewees4 suggested, that after the sperm is deposited on the labia pudendi or in the vagina, it may be taken up by a set of vessels—which, he admitted, had never been seen in the human female—whose duty it is to convey it to the ovary. This conjecture, he conceived, had been in part confirmed by the discovery of ducts, leading from the ovary to the vagina, in the cow and sow, by Dr. Gartner, of Copenhagen. The objections that may be urged against his hypothesis, Dr. Dewees remarks, " he must leave to others." We have no doubt, that his intimate acquaintance with the subject could have suggested' many that are pertinent and cogent. It will be obvious, that if we admit the existence of the ducts described by Gartner, it by no means follows, that they are inservient to the function in question. Independently, too, of the objection, that they have not been met with in the human female, it may be urged, 1 Principles and Practice of Obstetricy, Amer. edit., Washington, 1834. 2 See the details of an experiment with a similar object by Harlan, Medical and Physical Researches, p. 627, Philad., 1835. 3 Developpement de l'Homme, &c, traduit par Jourdan, p. 20, Paris, 1843. 4 A Compendious System of Midwifery, 7th edit., i hilad., 1835. FECUNDATION. 429 that if we grant their existence there would seem to be no reason, why closure of the os uteri after impregnation, or interruption of the vulvo- uterine canal by division of the vagina—as in the experiments of Dr. Blundell on rabbits—or division of the Fallopian tubes, should prevent subsequent conception,—in the first case during the existence of preg- nancy,—in the last two for life. These vessels ought, in both cases, to continue to convey sperm to the ovary; and extra-uterine preg- nancies or superfcetation ought to be constantly occurring. MM. PreVost and Dumas,1 and Dr. Ritchie,2 are amongst the most recent writers, who maintain, that fecundation takes place in the uterus, and the former gentlemen assign the following reasons for their belief. First. In their experiments, they always found sperm in the cornua of the uterus, and they conceive it natural, that fecundation should be effected only where sperm is. Secondly. In animals, whose ova are not fecundated until after they have been laid, fecundation must neces- sarily be accomplished out of the ovary; and, Thirdly. In their experi- ments on artificial fecundation, they have never been able to fecundate ova taken from the ovary. In reply to the first of these positions it has been properly remarked by M. Adelon,3 that the evidence of MM. Prevost and Dumas with regard to the presence of sperm elsewhere than in the uterus is only of a negative character; and that, on the other hand, we have the positive testimony of physiologists in favour of its existence in the Fallopian tubes and ovary. Haller asserts, that he found it there; and MM. Prevost and Dumas afford us evidence against their position respecting the seat of fecundation. They affirm, that on the first day after copulation, sperm was discoverable in the cornua of the uterus, and it was not until after the lapse of twenty-four hours, that it had attained the summits of the cornua. Once they detected it in the Fallopian tubes;—a circumstance, which is inexpli- cable under the view, that fecundation is accomplished in the uterus. Leeuenhoek and Hartsoker, also, found it in some cases in the Fallo- pian tube; and Bischoff, Wagner,4 and Dr. M. Barry5 discovered sper- matozoids in the fluid collected from the surface of the ovary, and within the capsular prolongations of the Fallopian tubes that enclose the ovaries. Still more recently, Dr. Barry,6 in two cases, found sper- matozoids within an ovum of the rabbit taken from the Fallopian tube. They were within the thick transparent membrane—zona pellucida— brought with the ovum from the ovary; and it will be shown pre- sently, that the positive penetration of the ovum by the spermatozoids has been confirmed by other observers. M. Pouchet,7 however, whilst he gives delineations of spermatozoids found in the middle of the Fal- lopian tubes of a rabbit on the surface of an ovum fifteen hours after copulation, denies that in the mammalia the sperm can ascend to the ovary. The contractions of the tubes; their ciliary movements ; the capillarity of the ducts, and the impassable mucus (mucus infranchis- 1 Annates des Sciences Naturelles, iii. 113. 2 Lond. Med. Gazette, cited in Amer. Journ. of the Med. Sciences, Jan., 1846, p. 187. 3 Physiologie de l'Homme, 2de edit., iv. 68, Paris, 1829. 4 Elements of Physiology, translated by Dr. R. Willis, p. 66, Lond., 1841. 5 Philosophical Transactions for 1839, p. 315. 6 Proceedings of the Royal Society, Dec. 8, 1842. ' Tliilorie Positive de l'Ovulation Spontanee, Atlas, Planche xv. fig. 9, Paris, 1847. 430 GENERATION. sable) he regards as invincible impediments; and maintains, categori- cally,—or, to employ the language of M. Raciborski,1 cited by M. Pouchet himself, " with a vigour and energy of dialectics hitherto unused in science," that " even if it could reach the germiferous organ it assuredly could not traverse the thick coats, which protect the ovules and arrive at them."2 He believes, moreover, that observers must have taken for spermatozoids on the ovary certain moving bodies, which he calls pseudo-zoo-spermes, and which, he says, can only be either micro- scopic entozoa, or the extremities of certain of the digitations, which form the fimbriated extremity of the Fallopian tube,—more probably the latter.3 He admits, however, that it seems to be almost certain, that these pseudo-zoo-spermes are exactly the same bodies as were seen by M. Donne',4 on the nasal mucous membrane of a man. M. Donnd observed epithelial shreds of this membrane separate spontaneously into minute conical portions, each of which had its own movement, like that of the spermatozoids; and we have elsewhere shown,—con- trary to the opinion of M. Pouchet,—that the spermatozoids them- selves are not perhaps entitled to any higher rank than that of ciliated epithelial cells. In reply to the second argument, it may be remarked, that analo- gies drawn from inferior animals are frequently loose and unsatisfac- tory ; and ought, consequently, to be received with caution. This is peculiarly one of those cases; for fecundation, in many animals, is always accomplished out of the body; and analogy might with equal propriety be invoked to prove, that in the human female the same thing must occur. Moreover, in certain oviparous animals—as in the common fowl—a single intercourse with the male may fecundate all the eggs she may lay in a season. In answer to the third negative position of MM. Prevost and Dumas, the positive experiments of Spal- lanzani may be cited, who succeeded in producing fecundation in ova that had been previously separated from the ovary. The evidence that conception—as the rule—takes place in the ovary, appears to be convincing. Ovarian pregnancy offers proof of it. Of this, Mr. Stanley, of Bartholomew's Hospital, has given an instructive example;5 and a still Fig. 431. more extraordinary one is related by Dr. Gran- ville.6 Other varieties of extra-uterine preg- nancy are confirmative of the same position. At times, the fcetus is found in the cavity of the ab- domen,—the ovum seem- ing to have escaped from the Fallopian tube when its fimbriated extremity Tubal Pregnancy. grasped the ovary to re- 1 De la Puberte et de l'Age Critique, p. 519, Paris, 1844. 2 Op. cit., p. 449. 3 0p. cit>) p> 416< 4 Cours de Microscopie, p. 175, Paris, 1844. b Medical Transactions, vol. vi. s Philosophical Transactions for 1820. FECUNDATION. 431 ceive and convey it to the cavity of the uterus. At other times, the foetus is developed in the Fallopian tube,—as in the marginal figure (Fig. 431),—some impediment having existed to the passage of the ovum from the ovary to the uterus. This impediment can be excited artificially, so as to give rise to tubal pregnancy. Nuck applied a liga- ture around one of the cornua of the uterus of a bitch, three days after copulation; and found, afterwards, two foetuses arrested in the Fallo- pian tube between the ligature and ovary. Von Baer1 detected an ovule in its passage along the Fallopian tube in a bitch; and Raspail asserts, that he once met with an ovule still attached to the ovary, which contained an embryo.2 It is obvious, then, from these facts, either that fecundation occurs in the ovary, or else that the ovum, when fecundated in the uterus, travels along the Fallopian tube to it; and thence back again to the uterus, which is not probable. It has been said, indeed, that ovarian and tubal pregnancies are exceptions to the rule; but no adequate evi- dence has been afforded of this. They certainly establish, that fecun- dation does take place in the ovary, and we are in want of positive, well authenticated cases of its having been accomplished elsewhere. To this conclusion M. Coste—who formerly was of opinion that fecun dation is effected normally in the Fallopian tube, and probably about its middle—has come of late. He frankly declared to the French Institute, that the result of his recent experiments had led him to renounce his former opinion, and to embrace that of the ancients, who placed the seat of fecundation in the ovary.3 But, to prevent impregnation, it is not necessary that the ovaries should be removed. It is sufficient to deprive them of all immediate communication with the uterus, by simply dividing the Fallopian tubes. On this subject, Dr. Haighton4 instituted numerous experiments, the result of which was, that after the operation a foetus was in no instance produced. The operation is much more simple than the ordinary method of spaying by the removal of the ovaries, and it has been suc- cessfully practised, at the recommendation of the author, on the farm of his friend, Thomas Jefferson Randolph, Esq., of Virginia. Simple division of the Fallopian tubes does not take away the sexual desire, as Haighton supposed; for the ovaries are still existent; but if they be removed, all desire is lost. A case is detailed of a natural defect of this kind in an adult woman, who had never exhibited the slightest desire for commerce with the male, and had never menstruated. On dissection, the ovaries were found deficient; and the uterus was not larger thau an infant's.5 Dr. Blundell has proposed the division of the tubes, and even the removal of a small portion of them, so as to render them completely impervious, when the pelvis is so contracted as not to admit of the birth of a living child in the seventh month; and he goes so far as to affirm, that the operation is much less dangerous than delivery by perforating the head, when the pelvis is greatly contracted. We have already remarked, that sperm has been found in the cavity 1 De Ovi M.'immalium et Hominis Genesi, Lips., 1827. 2 Chimie Organique, p. 262, Paris, 1833. ' Beraud, Manuel de Physiologie de l'Homme, &c, p. 439, Paris, 1853. 4 Philosoph. Transact, for 1797. fi Philosoph. Transact, for 1805. 432 GENERATION. of the uterus, and even in the Fallopian tubes. Fabricius ab Acqua- pendente maintained, that it could not be detected there; and Harvey contended, that in the case of the cow, whose vagina is very long, as well as in numerous other animals, it cannot possibly reach the uterus and that there is no reason for supposing it ever does. In addition, however, to the facts already cited, we may remark, that Mr. John Hunter1 killed a bitch in the act of copulation, and found the semen in the cavity of the uterus, conveyed thither, in his opinion, per saltum. Ruysch2 discovered it in the uterus of a woman taken in adultery by her husband and killed by him; and Haller3 in the uterus of a sheep killed forty-five minutes after copulation. An interesting case, in relation to this point, was published by Dr. Henry Bond,4 of Phila- delphia. A young woman, after having passed a part of the night with a male friend, destroyed herself early in the morning, by taking laudanum. On cutting open the uterus, it was found to be thickly coated with a substance having the appearance, and strong peculiar odour of sperm. One of the Fallopian tubes was laid open, and found to contain apparently the same matter; but it was not ascertained whether it possessed the seminal odour. More recently, Bischoff,5 in his investigations, found few or no spermatozoids in the vagina of bitches and rabbits, after coitus; but the uterus was quite full of them. This favours the view of Blumenbach,6 who supposes, that during the venereal orgasm, the uterus sucks in the sperm. It is impossible to explain the mode in which this is accomplished, but the fact of the entrance of the fluid into that organ, and even as far as the ovary, seems unquestionable. This Dr. Blundell7 admits, but he is disposed to think, that, in general, the rudiments from the mother, and the fecundating fluid meet in the uterus; as, in his experiments on rab- bits, he found—from the formation of corpora lutea, the developement of the uterus, and the accumulation of water in the uterine cavity— that the rudiments may come down into the uterus, without a previous contact with the sperm. His experiments, however, appear to prove nothing more, than that infecund ova may be discharged from the ovarium; and that if they are prevented from passing externally, owing to closure of the vagina or cervix uteri, the uterine phenomena alluded to may occur. They do not invalidate the arguments already brought forward to show, that the ovum must be fecundated in the ovarium. It has been suggested by Dr. Bostock,8 that the ciliary motions, which have been observed by Purkinje, Valentin,9 and others, on the 1 Philosoph. Transact, for 1817. 2 Thesaur. Anat. iv.; and Adversaria Anat. Med.-Chirurg., Dec. 1. 3 Element. Physiol., viii. 22. 4 American Journal of the Medical Sciences, No. xxvi., February, 1834, p. 403. 5 Entwickelungsgeschichte des Kaninchen-Eies, u. s. w., Leipz., 1842 ; cited by Mr. T. W. Jones, in Brit, and For. Med. Rev., Oct., 1843, p. 513 : and Op. cit. Also,,E. Thomas, Die Physiol, des Menschen, S. 52, Leipz, 1853; and J. Beclard, Trait j Ele- mentaire de Physiologie, p. 866r Paris, 1855. 6 Elements of Physiology, by Elliotson, 4th edit., p. 467, Lond., 1828. See, also, Giinther, Untersuchungen und Erfahrungen, Hannover, 1837, cited by Bischoff. 7 Principles, &c, of Obstetricy, Amer. edit., p. 56, Washington, 1834. 8 Physiology, 3d edit., p. 654, Lond., 1836. 9 Muller's Archiv., B. i. ; and translation in Dublin Journal of Med. Science, May, 1835; and in Edinb. New Philos. Journal, for July, 1835. FECUNDATION. 433 mucous membrane of the air-passages, and likewise on that of the generative organs, and whose office appears to be to propel substances along them, may have something to do with the propulsion of the sperm towards the ovary; and J. Miiller1 affirms, that " the mode in which the semen is conducted so far through the female generative organs, is no longer a problem requiring solution; for the discovery of the ciliary motion affords a solution of it." Dr. Sharpey,2 however, remarks, that the direction of these motions is from within outwards, so that he conceives it to be difficult to assign any other office to them than that of conveying outwards the secretion of the membrane; unless we suppose that they also bring down the ovum into the uterus. Prof. Wagner3 considers that the sperm reaches the ovary, partly by ciliary motion, which begins in the cervix uteri, partly by the contraction of the tubes, and partly by the motility of the spermatozoids; whilst Dr. Carpenter4 thinks it not unreasonable to suppose, that the last is the sole power; and that the transit of the spermatozoids from the vagina to the ovaries is effected by the same kind of action as that which causes them to traverse the field of the microscope. We have seen, however, that not only spermatozoids, but sperm itself, have been found in the uterus and Fallopian tubes. Future observations may shed farther light on this obscure subject. When treating of the views recently embraced by many physiologists as to the ovarian cause of menstruation, it was stated, that conception has been believed to be more easy during menstruation, or immediately before, or immediately after. Some, indeed, as M. Pouchet,5 have asserted, in the absence of adequate numerical evidence, the dangerous doctrine, that the aptitude scarcely exists at the middle of the interval between two menstrual periods, although there are numerous facts to show, that fecundation occurs in intermenstrual periods.6 M. Coste7 affirms, that the Morgue of Paris has, for years, yielded him many oppor- tunities for establishing this. The generality of those physiologists believe, that it is not necessary for the fecundating material of the male to come in contact with the ovum in the ovary—although in the vegetable, which is often taken as the analogue, such contact is known to be indispensable. They believe, that after an ovum has escaped, it may meet and be acted upon by the male sperm, either in the Fallopian tubes or in the uterus; and some think, notwithstanding the facts already mentioned of ovarian pregnancy, and of spermato- zoids having been found in the ovary, that neither the sperm nor any part of it can reach the ovary, and therefore impregnation can never be effected in it. A recent writer8 considers it most probable, that in the human female, as well as in the females of animals, the desire for 1 Elements of Physiology, translated by Baly, p. 1491, Lond., 1842. 2 Art. Cilia, Cyclop, of Anat. and Physiology, part vii. p. 633, July, 1836. 3 Elements of Physiology, translated by R. Willis, part i. p. 72, Lond., 1841. 4 Principles of Human Physiology, Amer. edit., p. 758, Philad., 1855, and Elements of Physiology, Amer. edit., p. 456, Philad., 1846. 6 Theorie Positive de la Fecondation des Mammiferes, Paris, 1842; Bulletin de l'Academie, Jan., 1845, p. 64; and especially his Theorie Positive de l'Ovulation Spon- tanee, &c, 9eme Loi, p. 170, Paris, 1847. 6 Ritchie, op. cit. ■" Op. cit., p. 203. 8 Girdwood, in London Lancet, Dec. 7 and 14,1844. VOL. II.—28 434 GENERATION. sexual intercourse is greatest at the menstrual period " or heat," espe- cially towards the decline of the discharge; at which latter period, he says, from observation on animals, it is proved that ova are usually discharged. Bitches, he says, are generally observed to be languid and to refuse the male during the first few days of heat; but after this they become lively, and readily admit of being lined; and analogous to this is the indisposition of the human female during the early part of each menstrual period, previous to the discharge becoming fully esta- blished; It could be understood, that a fecundating copulation might occur in the last days of menstruation, and perhaps soon after its ces- sation, through the male sperm coming in contact with an ovum sepa- rated from the ovary, and in the Fallopian tubes, or uterus;—for we are told authoritatively, by M. Pouchet,1 it is a " law," that, in the mammalia, fecundation never occurs unless the emission of ova coin- cides with the presence of seminal fluid, although the menstrual secre- tion itself—it might be presumed—would tend rather to throw out of the body the fecundating material; but if, as elsewhere said, and gene- rally believed, fecundation often occurs a short time before menstrua- tion, then the ovum could not have left the ovary,—if the facts above cited be correct,—and impregnation must have been effected in it. In the existing state of knowledge, then, this organ appears to be the seat of fecundation,—although the author" is not disposed to assert, that it cannot be accomplished at the time of, or soon after, the escape of the ovum from the ovarium. If the views of M. Coste, however, are correct, the contact of the sperm must take place early after the escape of the ovum, inasmuch as he found on opening birds and mam- miferous animals—which were kept separate from the males—that the ova, ten or twelve hours after their spontaneous separation from the ovaries, presented evident signs of decomposition; whence he infers, that fecundation can only be effected in the ovary, in the pavilion of the tube, and perhaps, also, in its upper third, and he regards the facts observed by him to be fatal to the views of those who consider fecun- dation practicable in other portions of the tube, and in the uterus.2 By many modern writers on the ovular theory of menstruation, it is maintained that a period of about eight days is needed for the passage of the unimpregnated ovum from the ovarium to the uterus, and its discharge from the female; M. Pouchet,3 however,—according to whose "tenth fundamental law," in the human species and the mammalia, the ovum and the sperm meet normally in the uterus, or in the portion of the Fallopian tubes near it, and there fecundation is accomplished,— extends the time much beyond this. His view is, that in the human species, a vesicle of De Graaf is torn normally at each menstruation, which spontaneously discharges its contained ovule, either immediately afterwards, or within the first four days following. A period of from two to six days is generally required for it to clear the tube, and it is subsequently retained in the uterus for from two to six days by the decidua. "If"—he adds—"during the time of its translation and so- 1 Theorie Positive de POvulation, &c, p. 209. * Comptes Rendus, xxx. 691, Paris, 1850. » Op. cit., pp. 297 and 467. FECUNDATION. 435 journ in the genital apparatus—that is, during the first twelve days that follow menstruation, and rarely up to the fourteenth day—there is sexual intercourse, fecundation may take place; but it can never be effected at a later period, because the ovum must manifestly have been dragged out by the decidua." It is an overwhelming objection, however, to these views, that the Jewish women are bound to observe abstinence from sexual intercourse for eight days; and it is affirmed by Dr. Girdwood,1 that "it is the cus- tom amongst Jews, who are scrupulous, for the wife to retire from the society of her husband for a period of thirteen days, reckoning from the first day of being 'nyddar;'—that is to say, by those who are strict, five days are kept, as prescribed by the Rabbinical law (for the pur- pose of making security doubly sure) in addition to the eight days enforced by the law of Moses,"2 and he adds "as a fact, that in general, among this singular people, no female is found to be a mother before at least nine calendar months and a half have elapsed,"—whence, he infers, that fecundation must have taken place immediately before the catamenial period. How fatal are such facts, observed on a large scale, to the dangerous doctrine of M. Pouchet and others, that intercourse cannot prove fecundating after twelve or fourteen days from the sepa- ration of the ovule from the ovary, especially when it is borne in mind, that the Jewish women are celebrated for being prolific. One single well observed antagonistic case would, indeed, be sufficient to disprove it, and such a one, recorded by Dr. Montgomery, of Dublin, is referred to hereafter, under the head of Duration of Pregnancy. In that case, the last menstruation occurred on the 18th of October; and the fecun- dating intercourse took place on the 10th of November, or twenty-three days afterwards. The case referred to by Dr. Dewees under the same head is equally opposed to the presumption. A similar case is given by Hirsch;3 and Dr. James Reid4 has collected several cases to deter- mine the duration of pregnancy in the human female, which establish the same point. Moreover, from the data afforded by MM. Pouchet and Raciborski, M. Coste infers, that "there is not in the entire month a single moment in which the emission of ova and impregnation are impossible."5 Granting that conception occurs in the ovarium, and that sperm is projected into the uterus, with or without the actions referred to; in what manner does the sperm exert its fecundating agency on the ova- rium? It is manifestly impossible, that the force of projection from the male can propel it not only as far as the cornua of the uterus, but also through the narrow media of communication between the uterus and ovary by the Fallopian tubes. This difficulty suggested the idea of the aura seminis or aura seminalis, which, it was supposed, might readily pass into the uterus, and through the tubes to the ovary. Dr. 1 Appendix to W. Tyler Smith, Parturition and the Principles and Practice of Ob- stetrics, Amer. edit., p. 386, Philad., 1849. 2 See, on this point, Hirsch, Jr., Einige praktische Bedenken gegen die jezt herr- schende Zeugungstheorie, in Henle und Pfeuffer's Zeitschrift, neue lolge, 1852, Bd. ii. S. 127 ; and in Canstatt's Jahresbericht, 1852, S. 209. 8 Op. cit. 4 Lancet, July 20, 1850; and Amer. Journ. of the Med. Sciences, Oct., 1850. p. 522. 6 Iiistoire Generate et Particuliere du Developpement, &c, p. 199, Paris, 1847. 436 GENERATION. Haighton, indeed, embraced an opinion more obscure than this, believ- ing, that the semen penetrates no farther than the uterus, whence it acts on the ovaria by sympathy;—and this obscure view has been adopted by some distinguished individuals. In opposition to the notion of the aura seminis, we have some striking facts and experiments. In all those animals, in which fecundation is accomplished out of the body, direct contact of the sperm appears necessary. Spallanzani and MM. Prevost and Dumas found, in their experiments on artificial fecundation, that they were always unsuccess- ful when they simply subjected ova to the emanation from sperm. Spal- lanzani took two watch-glasses capable of being fitted to each other, the concave surface of the one being opposed to that of the other. Into the lower he put ten or twelve grains of sperm, and into the upper about twenty ova. In the course of a few hours the sperm had evapo- rated, so that the ova were moistened by it; yet they were not fecun- dated; but fecundation was readily accomplished by touching them with the sperm that remained in the lower glass. A similar experiment was performed by MM. Pre'vost and Dumas. They prepared about an ounce and a half of a fecundating fluid from the expressed humour of twelve testicles, and as many vesicular seminales. With two and a half drachms of this fluid they fecundated more than two hundred ova. The remainder of the fluid was put into a small retort, to which an adopter was attached. In this, forty ova, were placed, ten of which occupied the hollowest part, whilst the rest were placed near the beak of the retort. The apparatus was put under the receiver of an air- pump, and air sufficient was withdrawn to diminish the pressure of the atmosphere one-half. The rays of the sun were now directed upon the body of the retort, until the temperature within rose to about 90°; and after the lapse of four hours, the experiment was stopped; and the following were the results. The eggs at the bottom of the adopter were bathed with a transparent fluid, the product of distillation. They had become tumid, as in pure water,but had undergone no developement. The eggs near the beak of the retort were similarly circumstanced, but all were readily fecundated by the thick sperm that remained at the bottom of the retort. No aura nor emanation from the sperm, conse- quently, appeared to be capable of impregnating the ova. Absolute contact was indispensable. This is probably the case with the human female, and if so, the sperm must proceed from the uterus along the Fallopian tube to the ovarium. The common opinion is, that during the intense excitement at the time of copulation, the tube is raised, and its digitated extremity applied to the ovary. The sperm then proceeds along it,—in what manner impelled we know not,—and attains the ovary. According to Dr. Blundell and others, during the time of inter- course, the whole of the tube is in a state of spontaneous movement. Mr. Cruikshank pithed a female rabbit when in heat, and examined the uterine system minutely. The external and internal parts of gene- ration were found black with blood; the Fallopian tubes were twisted like writhing worms, and exhibited a very vivid peristaltic motion; and the fimbriae embraced the ovaries—like fingers laying hold of an object—so closely and firmly as to require force, and even slight lace- ration to disengage them. Haller states, that by injecting the vessels FECUNDATION—AURA SEMINIS. 437 of the tube in the dead body, it assumed this kind of action. De Graaf, too, affirms, that he has found the fimbriated extremity adhering to the ovary, twenty-seven hours after copulation; and M. Magendie has seen the extremity of the tube applied to a vesicle. As excitement of some form would appear to be necessary to cause the digitated extremity of the tube to embrace the ovary, it would seem probable, that a female could not be impregnated without some consciousness of sexual union. This may be imperfect, as during sleep, or when in a state of stupor—either from spirituous liquors or narcotics—but still some impression must be made in order that fecun- dation may take place. It would not seem to be necessary, how- ever, that the excitement should be venereal, or appreciated by the brain, inasmuch as when infecund ova pass from the ovaries into the tubes, as during menstruation, the same application of the fringed extremities of the tubes to the ovary probably takes place. This may be owing to a reflex or excito-motory action commencing in the uterus or ovary. As the aura seminis appears to be insufficient for impregnation, it is obviously a matter of moment, that the sperm should be projected as high up the vagina as possible. It has been often observed, that where the orifice of the urethra does not open at the extremity of the glans, but beneath the penis, or at some distance from the point, the individual has been rendered less capable of procreation. In two cases, that fell under the care of the author, the urethra was opened opposite the corona glandis by a sloughing syphilitic sore; and the aperture continued, in spite of every effort to the contrary. The indi- viduals were married, and the fathers of three or four children; but after this occurrence they had no increase of their families. Many medico-legal writers have considered, that when the urethra terminates at another than its natural situation, impotence is the necessary re- sult,—and that although copulation may be effected, impregnation is impracticable. Zacchias,1 however, gives a case to the contrary. M. Belloc,2 too, asserts, that he knew of a person, in whom the orifice of the urethra terminated at the root of the fraenum, who had four child- ren that resembled the father, two having the same malformation; and Dr. Francis refers to the case of an inhabitant of New York, who, under similar circumstances, had two children. Many such cases, are, indeed, on record.3 We cannot, therefore, regard it as an absolute cause of impotence; but the inference is just, that if the semen be not projected far up the vagina, and in the direction of the os uteri, im- pregnation is not likely to be accomplished; a fact, which it might be of moment to bear in mind, where the rapid succession of children is an evil of magnitude. ' Yet, notwithstanding this weight of evidence, it has been affirmed by Professor Heim,4 that impregnation may take place by the simple contact of sperm with the lower part of the abdo- men. The answer to this view, by M. D'Outrepont,5 appears, however, 1 Quaestiones Medico-Legates, Lugd., 1674. 2 Cours de Medecine Legale, p. 50, Paris, 1819. 3 Beck's Elements of Medical Jurisprudence, 6th edit., p. 71, Philad., 1838. 4 Wochenschrift fiir die Gesammte Heilkunde; and Gazette M dicale, Sept. 25,1836. 5 Neue Zeitschrift fiir Geburtskunde, von Busch, d'Outrepont und Ritgen, B. iv. H. ii., Berlin, 1836; cited in Amer. Med. Intelligencer, p. 275, Nov. 1, 1837. 438 GENERATION. overwhelming. Heim relies on statements made by the parties that no penetration existed; but M. D'Outrepont properly observes, that whenever this has been alleged in a case of pregnancy, he has found if the parties were strictly questioned, that one or both of them admit ted, that the male organ might have been in the vagina, or at least in the vulva. The part, then, to which sperm is applied is the ovary,1 and by some it has been believed, that the liquor seminis is the substance that passes through the parietes of the follicle by imbibition, in order to reach the ovum. Mr. T. W. Jones2 states, that although he is not pre- pared to deny this; yet, when he takes into consideration all the evi- dence on the subject, he is of opinion, that there is no proof, that fecundation takes place until the ovum has escaped from the Graafian follicle, and comes into direct contact with the sperm. Bischoff and Wagner3 were, until recently, of opinion, that fecundation is accom- plished by the liquor sanguinis; but the latter now considers the view to be less admissible than he did formerly; urging, amongst other reasons, that a liquor seminis is positively not traceable in many, espe- cially of the lower, animals,—as worms, insects, &c,—the whole mass of the sperm being formed by spermatozoids alone. He urges further against the idea of the liquor seminis being the agent in fecundation, that its action on the ova would be impossible in many cases,—for instance, where fecundation takes place in water without any real act of copulation,—the sperm being ejected, and left to chance as to whe- ther it may come in contact with ova or not.4 Bischoff, too, has aban- doned his former opinion, and now maintains, that " spermatozoids and ova are constituents of an organism;" and that a positive contact of the two is necessary for the formation of a new being.5 It was before remarked, that Dr. Barry6 had seen spermatozoids within the ova of the rabbit; and their entrance into the ova of ani- mals has been confirmed by many observers; as by Dr. Neilson,7 Mr. Newport,8 Keber,9 and others. Bischoff, who opposed the view, now admits their passage into the ova of the frog and the rabbit. Meissner found them often within the ova of the former animal; and he de- scribes the ova of several insects with their micropyles, through which the spermatozoids enter;—and similar observations have been made by Leuckart.10 1 Brachet, Physiologie Elementaire de l'Homme, 2de edit., ii. 315. Paris et Lyon, 1855. 2 Report on the Ovum of Man and the Mammifera, in Brit, and For. Med. Rev., Oct., 1843, p. 525. 3 Elements of Physiology, by R. Willis, p. 74, Lond., 1844. 4 Art. Semen, Cyclopaedia of Anat. and Physiology, Pt. xxxiv. p. 507, Lond., Jan., 1849. 5 Muller's Archiv. fiir Anatom., No. v. p. 441, Berlin, 1847. 6 See, also, Monthly Journ. of Med. Science, Jan., 1855, p. 33, and Apr., 1855, p. 313, 7 Philosophical Transactions, 1852. 8 Philosophical Transactions, 1853, pp. 266-281; Carpenter, Principles of Human Physiology, Amer. edit., p. 764, Philad., 1855. 9 Ueber den Eintritt der Samenzellen in das Ei, Konigsberg, 1853, or De Spermato- zoorum Introitu in Ovula, Autore G. A. F. Keber, p. 18, Konigsberg, 1853, and Wagner, Nachtrag zum Nachtrag des Artikels Zeugung, in Wagner's Handworterbuch der Phy- siologie, iv. 1017, Braunschweig, 1853. 10 Hermann Weber, Annals of Physiology, in Brit, and For. Med.-Chir. Rev., Jan., 1856, p. 237. OVUM AFTER FECUNDATION. 439 Let us now inquire into the changes experienced by this body after a fecundating copulation. Fabricius, of Acquapendente,1 having killed hens a short time after they had been trodden, examined their ovaries, and observed,—amongst the small yellow, round granules, arranged racemiferously, which constitute those organs,—one having a small spot, in which vessels had become developed. This increased in size, and was afterwards detached, and received by the oviduct; becoming covered, in its passage through that tortuous canal and the cloaca by particular layers, especially by the calcareous envelope; and being ultimately extruded in the form of an egg. Harvey,2 in his experi- ments on the doe, made similar observations. He affirms, positively, that the ovary furnishes an ovum, and that the only difference, which exists amongst animals in this respect, is, that in some the ovum is hatched after having been laid; whilst in others it is deposited in a reservoir—a womb—where it undergoes successive changes. De Graaf3 instituted several experiments on rabbits for the purpose of detecting the series of changes in the organs from conception till delivery. Half an hour after copulation, no alteration was perceptible, except that the cornua of the uterus appeared a little redder than usual. In six hours, the coverings of the ovarian vesicles seemed reddish. At the expira- tion of a day from conception, three vesicles in one of the ovaries, and five in the other, appeared changed, having become opaque and red- dish. After twenty-seven, forty, and fifty hours, the cornua of the uterus and the tubes were very red, and one of the tubes had laid hold of the ovary; a vesicle was in the tube, and two in the right cornu of the uterus. These vesicles were as large as mustard seed. They were formed of two membranes, and were filled by a limpid fluid. On the fourth day, the avary contained only a species of envelope, called, by De Graaf, a follicle; this appeared to be the capsule that had con- tained the ovum. The ovum itself was in the cavity of the uterus; had augmented in size, and its two envelopes were very distinct. Here it remained loose until the seventh day, when it formed an adhesion to the uterus. On the ninth day, De Graaf observed a small opaque point, a kind of cloud, in the transparent fluid that filled the ovum. On the tenth day, this point had the shape of a small worm. On the eleventh, the embryo was clearly perceptible; and from this period, it underwent its full developement, until the thirty-first day, when de- livery took place. Malpighi4 and Vallisnieri5 also observed, in their experiments, that after a fecundating copulation, a body was developed at the surface of the ovary, which subsequently burst, and suffered a smaller body to escape. This was laid hold of by the tube, and con- veyed to the uterus. It is not, however, universally admitted, that this body is the impregnated ovum; some affirming, that it is a sperm similar to that of the male; and others, that it is an amorphous sub- stance, which, after successive developements, becomes the new in- dividual.6 1 Opera., Lips. 2 De Generatione, p. 228. 3 Tom. i. 310. 4 De Formatione Pulli in Ovo, Lond., 1673; and De Ovo Incubato, Lond., 1686. s Istoria della Generazione dell'Uomo, Discorsi Academ. iv., Venez., 1722-1726. 6 Adelon, Physiologie de l'Homme, iv. 74. 440 GENERATION. Haller exposed the feniales of sheep and other animals to males on the same day, and killed them at different periods after copulation for the purpose of detecting the whole series of changes by which the vesi- cle is detached from the ovary and conveyed to the uterus. Half an hour after copulation, one of the vesicles of the ovary appeared to be prominent; to have on its convexity a red, bloody spot, and to be about to break; in an hour or more, the vesicle gave way, and its interior seemed bleeding and inflamed. What remained of the vesicle in the ovary, and appeared to be its envelope, gradually became inspissated and converted into a body of a yellowish color, to which he gave the name corpus luteum. The cleft, by which the vesicle escaped, was observable for some time; but, about the eighth day, it disappeared. On the twelfth day, the corpus luteum became pale, and began to dimi- nish in size. This it continued to do until the end of gestation; and ultimately became a small, hard, yellowish or blackish substance, which could always be distinguished in the ovarium by the cicatrix left by it. Its size was greater, the nearer the examination was made to the period of conception. In a bitch, for example, on the tenth day, it was half the size of the ovary; yet it proceeded, in that case, from one vesicle only. In multiparous animals, as many corpora lutea existed as foetuses. The experiments of Haller1 have been frequently repeated with similar results. M. Magendie,2 whose trials were made on bitches, observed, that the largest vesicles of the ovary were greatly augmented in size, thirty hours after copulation; and that the tissue of the ovary surrounding them had acquired greater consistence; changed colour, and became of a yellowish-gray. This part was the corpus luteum. It, as well as the vesicles, increased for the next tlyee or four days; and seemed to contain, in its areolae, a white, opaque fluid, similar to milk. The vesicles now successfully ruptured the external coat of the ovary, and passed to the surface of the organ, still adhering to it, how- ever, by one side. Their size was sometimes that of a common hazel- nut ; but no germ was perceptible in them. The surface was smooth, and the interior filled with fluid. Whilst they were passing to the uterus, the corpus luteum in the ovary underwent the changes referred to by Haller. In similar experiments, instituted by MM. Prdvost and Dumas,3 no change was perceptible in the ovary during the first day after fecunda- tion ; but, on the second, several vesicles enlarged, and continued to do so for the next four or five days, so that from being two or three milli- metres in diameter, they were eight. From the sixth to the eighth day, the vesicles burst, and allowed an ovule to emerge, which often escaped observation, owing to its not being more than half a millimetre in diameter; but was clearly seen by MM. Prevost and Dumas by the aid of the microscope. This part they termed ovule, in contradistinc- tion to that developed in the ovary, which they called vesicle. The latter had the appearance, on its surface, of a bloody cleft, into which a probe might be passed; and in this way it could be shown, that the 1 Element. Physiologic, lib. xxix. sect. 1, Bern., 1766. 2 Precis de Physiologie, edit, citat., ii. 5:34. 3 Annates des Sciences Naturelles, iii. 135. OVUM AFTER FECUNDATION. 441 vesicle had ah interior cavity, which was the void space left by the ovule after its escape from the ovarium into the Fallopian tube. On the eighth day, in the bitch, the ovule passed into the uterus. All the ovules did not, however, enter that cavity at the same time,—an inter- val of three or four days sometimes occurring between them. When they attained the cavity, they were at first free and floating; and if examined with a microscope magnifying twelve diameters, seemed to consist of a small vesicle, filled with an albuminous, transparent fluid. If examined in water, their upper surface had a mammiform appearance, with a white spot on the side. This was the cicatricula. These ovules speedily augmented in size, and, on the twelfth day, foetuses could be recognised in them. Similar experiments, with like results, were made by Von Baer,1 Seiler,2 and others; and much minute attention has been paid to the subject by recent histologists,—by Wagner, Barry, Bischoff, T. W. Jones, Pouchet and Coste, more especially. As regards the ovarian changes, Wagner affirms, that after a fecundating intercourse, an in- creased flow of blood takes place to the ovaries; the vascular membrane of the Graafian vesicle enlarges; the granules mingled with its contents become greatly developed, and changed; and thickening and general increase of its walls, particularly of the base and sides, supervene; the ovum and other contents of the follicle are by this pressed forwards, or against that aspect of the follicle, which is in contact with the perito- neum, and which now becomes thinner and thinner, and finally bursts, so that the ovum escapes, and a cavity is left in the ovary, which is soon obliterated by the growth on all sides of the inner membrane of the follicle; a reddish, fleshy-looking mass sprouts from the walls towards the shrinking cavity, and the rent by which the ovum had escaped is finally closed. The follicle, thus altered, constitutes the corpus luteum. This is the generally received opinion, and it is analogous to that long since entertained by Haller. The outer layer of the Graafian follicle is considered to be of a fibrous structure, and therefore more elastic than the internal, whose structure is cellulo-vascular. The former, therefore, contracts more; and the latter being intimately united with it follows its movement, and consequently becomes thrown into folds or wrinkles, which project into the cavity: at the same time, accord- ing to M. Coste,3 it becomes hypertrophied, and a plastic secretion takes place into the cavity, which unites the folds together and is the blastema in the filling up of the follicle. The cicatrix left by the aper- ture in the follicle through which the ovum has escaped differs in form in different animals. In the human female it is an irregular and generally stelliform cleft.—But the corpus luteum will receive further attention presently. From the above facts, then, we may conclude, that the effect of fecun- dation is to excite the vesicles in the ovaries to developement; that the ova, within the germinal part, burst their covering; are laid hold of by 1 De Ovo Mammalium, &c, Epist., Lips., 1827. 2 Das Ei und Die Uebarmutter des Menschen, Dresd., 1832. 8 Histoire Generate et Particuliere du Developpement des Corps Organises, p. 249, Paris, 1S49; and Baly and Kirkes, Recent Advances in the Physiology of Motion, Senses, Generation and Developement, p. 52, Lond., 1848. 442 GENERATION. the Fallopian tube, and conveyed to the uterus, where they remain during the period of gestation. In the passage of the ova along the Fallopian tube it has generally been believed, that they experience but little change. They carry off according to Wagner, a small portion of the granular stratum of the vesicle with them, which appears hanging to them at first as an irregu- lar, ragged, discoidal appendage; but this is soon detached. The ovum gains a little in size; but there is still no trace of any special spot where the embryo originates. It would seem, however, from the researches of British embryologists, that the outer membrane of the ovum, which it acquired in the ovary, becomes swollen with moisture in the tube, and assumes the appearance of a thick, gelatinous-looking membrane, formed probably by cells—the proper chorion ; and by and by, the zona pellucida having disappeared, the newly-formed chorion comes to be the only investment of the yolk. All the observations on the ovum in the Fallopian tubes have, however, been made on animals. Of the human ovum whilst in the tubes, little or nothing is known. The exact time required by the ovum or ova to make their way into the uterus, has not been accurately determined. Mr. Cruikshank1 found, that in rabbits forty-eight hours were necessary. Dr. Haighton2 divided one of the Fallopian tubes in a rabbit; and, having exposed the animal to the male, he observed that gestation occurred only on the sound side. On making this section after copulation, he found, that if it were executed within the first two days, the descent of the ovules was prevented; but if it were delayed for sixty hours, the ovules had passed through the tube and were in the cavity of the uterus. A case is quoted by writers on this subject, on the authority of a surgeon named Bussieres, who observed an ovoid sac, about the size of a hazelnut and containing an embryo, half in the Fallopian tube and half adherent to the ovary.3 The minuteness of the calibre of the E'allopian tube is not as great a stumbling-block in the way of understanding howythis passage is effected as might appear at first sight. The duct is, doubtless, ex- tremely small in the ordinary state; but it admits of considerable dila- tation. M. Magendie4 asserts, that he once found it half an inch in diameter; and the size of the ovum, we have seen, is only about 2o5th part of an inch. The period that elapses between a fecundating copulation and the entrance of the ovum into the uterus is different in different "animals. In sheep, according to Haller5 and Kuhlemann,6 it happens on the seven- teenth day. In rabbits, it is uncertain, but occurs generally ou the third or fourth day after copulation ;7 in bitches on the fifth, according to some, but not till after the lapse of ten or twelve days, according to others; and in the human female, perhaps about the same time; yet Mr. Burns infers from analogical evidence, that we should be more 1 Philosoph. Transactions for 1797. 2 Ibid., lxxxvii. 304. 3 Adelon, Physiologie de l'Homme, edit, cit., iv. 78. 4 Precis, &c, edit, cit., p. 535. 5 Element. Physiol., viii. 59. 6 Observ. quaedam circa Negotium Generationis in Ovibus fact., Gotting., 1753. 7 Recherches sur la Generation des Mammiferes par Coste, suivies de Recherches sur la Formation des Embryons, par Delpech et Coste, Paris, 1834. OVUM AFTER FECUNDATION. 443 justified'in the belief, that the ovum, in the human female, does not enter the uterus until at least three weeks after conception.1 M. May- grier refers to a case of abortion twelve days after copulation; the abortment consisting of a vesicle, shaggy on its surface, and filled by a transparent fluid. A case that has by many been considered one of the most instructive that we possess on this subject is„given by Sir Everard Home,2 and although, as Dr. Granville3 has remarked, it has lately been the fashion to doubt its accuracy, or to esteem it morbid, there is not sufficient reason, perhaps, to discard it, more especially as Mr. Bauer's microscopic examination of the ovule, and description of its structure correspond with the more recent discoveries of Professor Boer. A servant-maid, twenty-one years of age, had been courted by an officer, who had promised her marriage, in order that he might more easily accomplish his wishes. She was but little in the habit of leaving home, and had not done so for several days, when she requested a fellow-servant to remain in the house, as she was desirous of calling upon a friend, and should be detained some time. This was on the 7th of January, 1817. After an absence of several hours, she returned with a pair of new corsets, and other articles of dress which she had purchased. In the evening she got one of the maidservants to assist her in trying on the corsets. In the act of lacing them, she complained of considerable general indisposition, which disappeared on taking a little brandy. Next day, she was much indisposed. This was attri- buted to the catamenia not having made their appearance, although the period had arrived. On the following day, there was a wildness in her manner, and she appeared to suffer great mental distress. Fever supervened, which confined her to her bed. On the 13th, she had an epileptic fit followed by delirium, which continued till the 15th, when she expired in the forenoon. On making inquiries of her fellow-ser- vants, many circumstances were mentioned, which rendered it highly probable, that on the morning of the 7th, when she was immediately on the point of menstruating, her lover had succeeded in gratifying his desires; and that she had become pregnant on that day; so that, when she died, she was in the 7th or eighth day of impregnation. Dissection showed the uterus to be much larger than in the virgin state; and con- siderably more vascular. On accurately observing the right ovarium, in company with Mr. Clift, Sir Everard noticed, upon the most promi- nent part of its outer surface, a small ragged orifice. This induced him to make a longitudinal incision in a line close to the orifice, when a canal was found leading to a cavity filled with coagulated blood, and surrounded by a narrow yellow margin, in the structure of which the lines had a zigzag appearance. The cavity of the uterus was then opened, by making an incision through the coats from each angle; and from the point where these incisions met, a third incision was continued down through the os uteri to the vagina. The os uteri was found com- pletely blocked up by a plug of mucus, so that nothing could have escaped by the vagina; the orifices leading to the Fallopian tubes were 1 The Principles of Midwifery, &c, 3d edit, p. 132, Lond., 1814. 2 Philosophical Transactions for 1807, p. 252; and Lectures on Comparative Ana- tomy, iii. 288, Lond., 1823. 3 Graphic Illustrations of Abortion, &c, p. 7, Lond., 1834. 444 GENERATION. both open, and the inner surface of the uterine cavity was composed of a beautiful efflorescence of coagulable lymph resembling the most delicate moss. By attentive examination, Sir Everard discovered a small, spherical, transparent body concealed in this efflorescence, which was the impregnated ovum. This was submitted to the microscopic investigation* of Mr. Bauer, who made various drawings of it, and detected two projecting points, which were considered to mark out even at this early period, and before the ovum was attached to the uterus, the seat of the brain and spinal marrow. This case—if admitted as a correct observation—shows, that an ovum had left the ovary, and was in the interior of the uterus, prior to the seventh or eighth day after impregnation. AVeber and Von Baer, however, have each recorded a case in which there was an opportunity for examining the embryo, probably eight days after a fecundating copulation; but no ovum was detected either in the uterus or tube, and it must be admitted, that some of the best observers—as will be stated hereafter—do not consider that the ovum enters the uterus before the 10th or 12th day after it quits the ovary. On comparing the degree of advancement of the foetus in the human ovum, as described by dif- ferent observers, with that of fthe foetus in the dog, cat, and sheep, at known periods, Dr. Allen Thomson1 hazards the opinion, that it does not arrive in the uterus before the eleventh or twelfth day after con- ception :—Valentin, indeed, thinks, the twelfth or fourteenth day. From this discrepancy amongst observers, it is manifest, that our knowledge on the matter is by no means definite. But—it has been asked—is it a mere matter of chance which of the ovarian vesicles shall be fecundated; or are there not some riper than the rest, that receive, by preference, the vivifying influence of the sperm? MM. PreVost and Dumas have shown, that such is the case with oviparous animals. They found, in their experiments, that nut only were the vesicles of the ovaries of frogs of different sizes, but that the largest were always laid first, whilst the smallest were not to he deposited until subsequent years. In all animals, whose eggs were fecundated externally, they seemed evidently prepared or maturated. We have, too, the most indubitable evidence that birds—although unquestionably virgins—may lay infecund eggs; and analogy would lead us to believe, that something similar may happen to the vivipa- rous animal; a position which has been confirmed by direct observa- tion. In all cases in which an ovum has escaped, a cavity of course is left in the ovarium, which is filled up, in the manner already mentioned, by a growth from the Graafian follicle, which constitutes the corpus luteum. Not longer ago than the year 1808, the existence of this body in the ovarium was held to be full proof of impregnation. In that year, Charles Angus, Esq., of Liverpool, England, was tried at the Lancaster Assizes, for the murder of Miss Burns, a resident of his house.2 The symptoms previous to her decease, and the appearances observed on 1 Art. Generation, in Cyclop, of Anat. and Physiol., part. xiii. p. 454, Feb., 1838. 2 Edinb. Med. and Surg. Journal, v. 220. OVUM AFTER FECUNDATION. 445 dissection, were such as to warrant the suspicion that she had been poisoned. The uterine organs were also found to be in such a state as to induce the belief, that she had been delivered a short time before her death of a foetus, which had nearly arrived at maturity. It was not, however, until after the trial, that the ovaria were examined in the pre- sence of a number of physicians; when a corpus luteum was distinctly perceived in one of them. The uterus was taken to London, and shown to several of the most eminent practitioners; all of whom appear to have considered, that the presence of a corpus luteum proved the fact of pregnancy beyond a doubt. Such, indeed, is the positive averment of Haller,1 an opinion which was embraced by Dr. Haighton,2 who maintained, that they furnish "incontestable proof" of previous im- pregnation. It was this belief,—coupled with the fact, that division of the Fallopian tubes, in his experiments, prevented impregnation, whilst corpora lutea were found, notwithstanding, in the ovary,—which led him to the strange conclusion, that the semen penetrates no farther than the uterus, and acts upon the ovaria by sympathy. Sir Everard Home3 affirmed, that corpora lutea exist independently of impregnation. "Upon examining," said he, "the ovaria of several women, wrho had died virgins, and in whom the hymen was too perfect to admit of the possibility of impregnation, there were not only distinct corpora lutea, but also small cavities around the edge of the ovarium, evidently left by ova, that had passed out at some former period;" and he affirms, that whenever a female quadruped is in heat, one or more ova pass from the ovaria to the uterus, whether she receives the male or not. This view of the subject appears to have been first propounded by Blumenbach,4 who remarks that the state of the ovaria of females, who have died under strong sexual passion, has been found similar to that of rabbits during heat; and he affirms, that in tfte body of a young woman, eighteen years of age, who had been brought up in a convent, and had every appearance of being a virgin, Vallisnieri found five or six vesicles pushing forward in one ovarium, and the corresponding Fallopian tube redder and larger than usual, as he had frequently ob- served in animals during heat. Bonnet, he adds, gives the history of a young lady, who died vehemently in love with a man of low station, and whose ovaria were turgid with vesicles of great size; and similar facts have been recorded by numerous observers.5 It has been already remarked, under Menstruation, that the periodical recurrence of that function has been supposed by some to consist in the production and developement of vesicles in the ovary; that is, of a matured ovum which is periodically brought forward either to be expelled with the menstrual flux, or to be destroyed in the genital organs. Buffon, again, maintained, that instead of the corpus luteum of Hal- ler being the remains of the ovule, it is its rudiment; and that the corpus exists prior to fecundation,—as he, also, found it in the virgin. 1 Element. Physiolog., xxix. 1. 2 Philosoph. Transact., lxxxvii. 159. 3 Philosoph. Transact, for 1817 and 1819; and Lectures on Compar. Anat., iii. 304. 4 Comment. Soc. Roy. Scient., Gotting., ix. 128 ; and Elliotson's edit, of Blumen- bach's Phy*iology, 4th edit., p. 468, Loud., 1828. b Pouchet, Thuorie Positive de l'Ovulation Spontanee, &c, p. 127, Paris, 1847. 446 GENERATION. Lastly, Dr. Blundell1 states, that he has in his possession a prepara- tion, consisting of the ovaries of a young girl, who died of cholera under seventeen years of age, with the hymen, which nearly closed the entrance of the vagina, unbroken. In these ovaries the corpora lutea are no fewer than four; two of them being a little obscure, but easily perceptible by an experienced eye. The remaining two are very dis- tinct, and differ from the corpus luteum of genuine impregnation merely by their more diminutive size and the less extensive vascularity of the contiguous parts of the ovary. "In every other respect," says Dr. Blundell, "in colour and form, and the cavity which they contain, their Fig. 432. Corpora Lutea of different periods. B. Corpus luteum of about the sixth week after impregnation, showing its plicated form at that period. 1. Substance of the ovary'. 2. Substance of the corpus luteum. 3. A grayish coagulum in its cavity; after Dr. Patterson. A. Corpus luteum, two days after delivery, d. In the twelfth week after delivery. appearance is perfectly natural,—indeed, so much so, that I occasion- ally circulate them in the class-room, as accurate specimens of the luteum upon the small scale." Mr. Stanley2 confirms the fact of the corpora lutea of virgins being of smaller size than those that are the consequences of impregnation; and Dr. Montgomery3 says, he has seen many of these virgin corpora lutea, "as they are unhappily called," and has preserved several specimens of them ; but not in any instance did they present what he would Fig. 433. regard as even an approach to the as- semblage of characters belonging to a true corpus luteum,—the result of im- pregnation ; from which, according to him, they differ in the following particu- lars:—1. There is no prominence or enlargement of the ovary over them. Corpus Luteum in the Third Month. 2. The external cicatrix is almost always wanting. 3. There are often several of them found in both ovaries, especially in subjects who have died of tubercular diseases, such as phthisis, in which case they appear to be 1 Researches, Physiol, and Pathological, p. 49, Lond., 1825. 2 Transactions of the Royal College of Physicians of London, vol. vi. s An Exposition of the Signs and Symptoms of Pregnancy, &c, p. 245, Lond., 1837, or Amer. Med. Lib. edit., Philad., 1839 ; or art. Signs of Pregnancy and Delivery, in Cyclop, of Pract. Medicine, Amer. edit, by the author, Philad., 1844. CORPUS LUTEUM. 447 merely depositions of tubercle, and are fre- quently without any discoverable connexion with the Graafian vesicles. 4. They present no trace whatever of vessels in their sub- stance, of which they are, in fact, entirely destitute, and of course cannot be injected. 5. Their texture is sometimes so infirm, that it seems to be merely the remains of a coagu- lu/n, and at others appears fibro-cellular like that of the internal structure of the ovary; but never presents the soft, rich, lobulated, and regularly glandular appearance, which Hunter meant to express, when he described them as " tender and friable like glandular flesh." 6. In form they are often triangular, „ , . . t, , , ., „ ■' _ iiii Corpus Luteum at the end of the or square, or of some figure bounded by Ninth Month. straight lines; and 7. They never present either the central cavity or the radiated or stelliform white line, which results from its closure. Figures 433 and 434, from Dr. Montgomery, represent the corpus luteum in the third, and at the end of the ninth month respectively. Dr. William Davidson,1 of Edinburgh, however, has published three dissections of females—not one of whom was pregnant—and in each, corpora lutea were found. They all possessed the characters assigned them by Dr. Montgomery, a central cavity, or fibrous coagulum; an oval form, and a radiated white cicatrix in the centre, just about the central body, which was immediately under the peritoneal coat. This last point is dwelt upon by Dr. Bobert Lee, who maintains, that false corpora lutea are never observed in immediate connexion with the peritoneum,—a small portion of stroma intervening. One of the females had been in a weakly condition for some years, and had no children; another was unmarried, and had menstruated three days previous to her death ; of the third, there was no history, but all the organs were healthy, and the Fallopian tubes and uterus in every respect natural. Dr. Davidson expresses his confident opinion, that in none of the cases had there been impregnation prior to the appear- ance of these bodies; and he refers to Professors Alison, Allen Thom- son, John Reid, and Goodsir, in proof of the accuracy of his statement, and of their perfect resemblance to true corpora lutea. He states, as the result of his investigations, the belief, that impregnation cannot take place without the appearance of a true corpus luteum, but that a true corpus luteum may appear independently of' impregnation. That the latter is the case in animals has been shown by the recent re- searches of Bischoff2 and others. It is not yet decided at what*period the central cavity disappears or closes up to form the stellated line. Dr. Montgomery thinks he has invariably found it existing up to the end of the fourth month. He has one specimen in which it was closed in the fifth, and another 1 Lond. and Edinb. Monthly Journal of Med. Science, Dec, 1841. 2 Beweis der von Begattung unabhiingigen periodischen Reifung und Loslosung der Eier, Giessen, 1844 ; translated in Lond. Med. Gaz., Jan. 13, 17, &c, 1845. Fig. 434. 448 GENERATION. in which it was open in the sixth; but later than this he has never found it. Fig. 435. e / g h Successive Stages of the Formation of the Corpus Luteum, in the Graafian follicle of the Sow, as seen in Vertical Section. At a is shown the state of the follicle immediately after the expulsion of the ovum, its cavity being filled with blood, and no ostensible increase of its epithelial lining having yet taken place; at b, a thick- ening of this lining has become apparent; at c, it begins to present folds which are deepened at d, and the clot of blood is absorbed pari passu, and at the same time decolorized ; a continuance of the same process as shown at e, /, g, h, forms the Corpus Luteum, with its stellate cicatrix. The structure of the corpus luteum is of a peculiar kind, and is not distinctly seen in small animals, or in those that have numerous lit- ters; but in the cow, which commonly has only one calf at a birth, it is so large, according to Sir Everard Home,1 that, when magnified, the structure can be made out. It is a mass of thin convolutions, bearing a greater resemblance to those of the brain than to any other Fig. 436. Fig. 437. Corpora Lutea. organ. Its shape is irregularly oval, with a central cavity, and in some animals, its substance is of a bright orange colour, when first exposed. The corpora lutea are found to make their appearance im- 1 Lect. on Comp. Anat., iii. 303. CORPUS LUTEUM. 449 mediately after puberty, and they continue to succeed each other, as the ova are expelled, till the period arrives when impregnation can no longer be accomplished. Sir Everard's theory, regarding these bodies, is that they are glands, formed purposely for the production of ova,— and a similar view is entertained by Seiler j1 that they exist previous to and are unconnected with sexual intercourse; and, when they have fulfilled their office of forming ova, they are removed by absorption, whether the ova be fecundated or not. Figures 436 and 437 afford an external and internal view of a hu- man ovary, that did not contain the ovum, from which a child had been developed. It was taken immediately after the child was born. Fig. 438. Fig. 439. Corpora Lutea. The corpus luteum is nearly of the full size. Figs. 438 and 439 afford an external and internal view of the ovary, from which the impreg- nated ovum had escaped. Figure b exhibits how much the corpus luteum had been broken down. In it is seen a new corpus luteum forming. From all these facts, it was at one time concluded by Sir Everard Home,2 Messrs. Blundell, Saumarez,3 Cuvier, and others,4 that some- thing resembling a corpus luteum may be produced independently of sexual intercourse, by the mere excitement of high carnal desire, and perhaps without it, during which the digitated extremity of the Fallopian tube embraces the ovary, a vesicle bursts its covering, and a yellow body remains. The ovule conveyed along the tube into the uterus being infecund, undergoes no farther developement; so that unimpregnated ova may,—it was inferred,—under such circumstances, 1 Das Ei und die Gebarmutter des Menschen, u. s. w., Dresd., 1832. 2 Op. cit., iii. 304. 3 A New System of Physiology, i. 337. 4 For a history of the opinions entertained at various times regarding the corpus lu- teum, see Dr. Patersou, Edinb. Med. and Surg. Journal, April, 1841, p. 402. VOL. II.—29 450 GENERATION. be discharged, as we observe in the oviparous animal. That infecund ova are thus discharged by the mammalia is now universally admitted. It has been generally denied, however, of late, that the intervention of the male has any influence whatever over it; but the observations of M. Coste1 demonstrate, that this opinion is too exclusive. He found in rabbits killed from ten to fifteen hours after intercourse, that the ova had generally quitted the ovaries; whilst they were as generally re- tained where the female was carefully kept from the male. When pregnancy is over, the corpus luteum gradually diminishes in size, and disappears. Dr. Montgomery was unable to fix the exact period of its total disappearance; but he has found it distinctly visible so late as the end of five months after delivery at the full time, but not beyond this period. It would seem, therefore, that a few months after the termination of pregnancy, all traces of the corpus luteum are lost; and that, consequently, it must be impracticable to decide how frequently impregnation has taken place, by examining the ova- ries. Such have been the sentiments of physiologists in regard to the formation of corpora lutea;—a marked difference being admitted by most of them to exist between those that result from the escape of in- fecund ova, and those that are the consequence of the escape of the impregnated: whilst others have regarded them as identical. With those, however, who maintain that ova always leave the ovary prior to fecundation, it would seem to be consistent to presume, that the corpora lutea are alike in all cases; and hence, that the ovaries can furnish no probable solution after death, by the appearance presented by the corpora lutea, of the question, whether the female had been impregnated or not. M. Eaciborski at one time maintained this doc- trine, affirming, that not merely as a result of conception, but at each menstrual period, the discharge of an ovum is followed by the forma- tion of a corpus luteum. Since then, however, he appears to have changed his sentiments as regards the human female, but maintains that such is the fact in animals,—after each period of heat a corpus luteum being formed, which is undistinguishable from that formed after fecundation. The conclusions to which he now arrives are the following. First. Corpora lutea are produced by hypertrophy of the granular substance which lines the internal membrane of the Graafian vesicle. Secondly. The transformation of this substance commences as soon as the ovule attains maturity, and the vesicle is then prepared to break and give passage to it. Thirdly. As soon as the Graafian folli- cles burst, the transformation is rapidly developed. But an important distinction occurs. If the ovum has been expelled spontaneously—as at every menstrual period—the granulations increase in number and size, under the form of a thin, yellowish membrane, adherent to the membrane of the vesicle; and, in the cavity which it forms a small clot of blood is to be found. If, on the contrary, conception coincides with the expulsion, the elements of the granular tunic increase so much in size and number, that in a little time they form a voluminous 1 Histoire Generale et Particuliere du Developpement des Corps Organises, p. 183, Paris, 1847. CORPUS LUTEUM. 451 mass, which fills the whole cavity of the vesicle. In the centre of this yellow mass, a small whitish fibrinous tissue—the cicatrix indicating a former cavity—is with difficulty distinguishable. Fourthly. In all females delivered at the full period, corpora lutea of this description exist; but they rapidly waste and disappear after delivery. Fifthly. It results from the above, that by simple inspection cases of simple spontaneous expulsion of ova may be readily distinguished from those that have been followed by impregnation.1 They, who consider that fecundation is not accomplished in the ovary, must believe, that the ovarian changes, which accompany and signalize fecundation are produced by some reflex action from the uterus; and such is the view embraced by Dr. Ritchie, who has made elaborate in- quiries on this whole subject. A similar view is maintained by M. Coste.2 " When the fecundated ovum"—he remarks—" has attached itself to the uterus, it impresses on that organ an increase of activity, which lasts through the whole term of utero-gestation; extends its in- fluence to the ruptured ovarian capsule, and gives a greater intensity to the process of cicatrization." It has been a matter of discussion with histologists, whether the sub- stance of the corpus luteum is deposited within the Graafian vesicle, externally to it, or between its layers, or whether it does not consist of a hypertrophied condition of the inner layer or ovisac. Von Baer, Valentin, Wagner, Bischoff, Raciborski, Zwicky, and others embrace the first and most probable opinion; and from an examination of many human corpora lutea in various stages of their growth, Dr. Baly3 is satisfied, that this is the correct opinion; whilst MM. Pouchet and Coste embrace the last view; Dr. Robert Lee, Mr. T. Wharton Jones, the second; and Drs. Montgomery, Barry, Paterson, Ritchie, F. Renaud, and others, the third. Dr. Ritchie4 has shown, that a great variety of changes may take place in the ovary after the ovum has been discharged, amongst which may be included all the appearances depicted by those observers. Besides varying in seat, they differ considerably, he states, in aspect and character;—some being of a white colour, corpora albida; others brain-like,—corpora cephaloidea; and others, at first, similar to the last, but becoming subsequently of a decidedly red colour—corpora rubra. The corpora albida may exist under two forms;—first as soft bodies of a yellowish fatty appearance, having the outer coat much thickened, whilst the inner remains as a delicate diaphanous pellicle; these, after a long period, present themselves as yellowish-white, and generally globular bodies, more or less fissured from their contraction, and sometimes in process of absorption; having a granular looking structure, and seldom divisible into laminae by dissection; and secondly, as dense bodies of a whitish, shining, firm structure, the inner coat being the seat of those changes, and the outer adhering loosely as a 1 Bulletin de l'Academie Royale de Medecine, Oct. and Nov., 1844 ; cited in Med. Examiner, June, 1845, p. 384. 2 Op. cit., p. 259. 3 Baly and Kirkes, Recent Advances in the Physiology of Motion, the Senses, Genera- tion and Developement, p. 54, Lond., 1848. 4 Op. cit.; also, Carpenter, Principles of Human Physiology, 2d Amer. edit., p. 597. 452 GENERATION. transparent pellicular layer. The inner layer has the appearance of a thick, opaque, deeply wrinkled cyst; or is at times partially diapha- nous, and of a shining pearly aspect, and white colour; and sometimes contains a yellow, greenish, transparent fluid, or a clot of blood, either unchanged, or converted into a yellow or black pigment. Of the cor- pora cephaloidea Dr. Ritchie depicts many varieties, according as the cerebriform matter is deposited between the laj-ers of ruptured follicles, having transparent pellicular walls, or having their inner or outer coat thickened; or externally to the two inner layers of the follicle. The last variety only was met with exclusively in the fecundated female. They were generally distinguished by large, persistent, white, glisten- ing cavities. The granular cephaloid matter was sometimes found quite absorbed a few days after delivery; but, in other instances, it underwent changes characteristic of the next class. The corpora rubra are peculiar to the impregnated and suckling female—in the period between the eighth and thirteenth months after conception. They appeared to Dr. Ritchie to be a conversion of the corpora cephaloidea, arising out of a higher and more perfect organiza- tion. Down to the seventh month of utero-gestation, the cysts con- tained in the ovaries do not differ from the cephaloid bodies found in the unimpregnated state,* except that they are sometimes plumper; more vascular; better developed, and have their inner layer more fre- quently thickened. A change of the granular hue then commences, which becomes more and more decided ; so that by the end of the first month after delivery, it is of a decided rose colour, changing to a still more florid hue on exposure to air. Its cavity also contracts, so as to leave only a stellated point, or a curved groove, with a fibrous appear- ance in the surrounding substance. Although corpora rubra are found exclusively in the latter months of pregnancy, or in the puerperal state, yet, they are not always present in those conditions. The form of corpora cephaloidea described above, and the corpora rubra, according to Dr. Ritchie, alone coincide with pregnancy. The cause of the yellow colour of the corpora lutea has been, a ground of dispute; but it is obviously of no more moment than that of the other varieties of colour presented by those bodies. By MM. Pouchet,1 Raciborski,2 and others, it has been ascribed to extravasation and imbi- bition by the hypertrophied lining membrane, similar to that which occurs in ecchymosis, or in the neurine in cases of encephalic hemor- rhage; but others3 do not accord with this view. From the appear- ances presented under the microscope, Dr. Meigs argues, that the yolk of eggs and the yellow matter from a corpus luteum "are of the same ap- parent constitution, form, colour, odour, coagulability, refractive power, and microscopic appearance;" and M. Coste appears to be of the same opinion. Dr. Meigs,4 for these reasons, considers it a true " vitellary x Theorie Positive de l'Ovulation Spontanee, p. 146, Paris, 1847. 2 De la Puberte et de l'Age Critique chez la Femme, p. 437, Paris, 1844. s Coste, Op. cit., and Kirkes and Paget, Manual of Physiology, 2d Amer. edit., p. 497, Philad., 1853. 4 Transactions of the American Philosophical Society for 1847, p. 131; and Obste- trics : the Science and the Art, by Charles D. Meigs, M. D., p. 107, Philad., 1*49. CORPUS LUTEUM. 453 matter." The propriety of such a name may be questioned, however, upon the same ground, that we might hesitate in calling a substance which contains cholesterin, biliary matter; as cholesterin is a constitu- ent of many morbid formations totally unconnected with the liver, or its secretion. That the colouring matter of the vitellus or yolk and that of thecorpus luteum are analogous—if not identical—is probable, under the view which we embrace,—that the corpus luteum is constituted essentially of the enlarged cells and granules of yellow fatty matter that line the Graafian vesicle and form the membrana granulosa. The enlargement of the cells, according to Zwicky,1 who minutely examined the corpora lutea in cows and sows, appears to depend on an accumu- lation of the fat granules which the Graafian vesicles always contain; and the yellow colour, when it exists, is contained in those fat granules and other fatty particles. When it is borne in mind, that the vitellary matter of the ovum must be secreted from the same lining membrane of the Graafian vesicle as the membrana granulosa, thpre need be no difficulty in comprehending, that the yolk and the corpus luteum may be of identical or analogous composition, and conduct themselves alike under the microscope, and the employment of reagents. In function, however, they are in no respect identical or analogous. It is obvious, that the value of the corpora lutea as an index of fecundation is in an unsettled condition; and, consequently, the medi- cal jurist must be exceedingly cautious, from their appearance, in giving decided testimony in a court of justice; for although, as has been seen, some observers—Dr. Montgomery and Dr. Dalton,2 for ex- ample—have pronounced strougly in regard to the markedly distinc- tive characters of the corpora lutea of impregnation; and M. Coste3 expresses his belief in the possibility of distinguishing by them whe- ther a female was or was not pregnant, and is persuaded that important applications will ultimately be made of this knowledge in legal medi- cine; others—as Dr. Davidson—have deposed as strongly to the ab- sence of such characteristics; and all must admit, that in the present state of knowledge, the mere fact of the existence of a'corpus luteum ought scarcely to be taken as a positive evidence of previous impreg- nation; yet, if it were larger than a common pea, it might be regarded as strong presumptive evidence in the affirmative.4 M. Longet5 affirms, that the corpora lutea of the unfecundated state rapidly run through their stages; never attain a high degree of developement; have a size not much less than the corpora lutea of impregnation; rapidly assume the yellow hue; become shrivelled in a few days; and, before a month or two, are retracted into, and completely confounded with the tissue of the ovary; whilst the corpora lutea of impregnation, participating in the congestion and activity of the physiological process in all the sexual organs, and especially in the uterus during gestation, attain a 1 De Corporum Luteorum Origine atqiie Transformatione, cited by Mr. Paget in his Report on the Progress of Human Anatomy and Physiology, in the years 1844-5, in British and Foreign Medical Review, July, 1846, p. 290; also, Baly and Kirkes, op. cit., p. 53. 2 Prize Essay on the Corpus Luteum of Menstruation and Pregnancy, in Transactions of the Amer. Med. Assoc, iv. 547, Philad., 1851. 3 Op. cit., ]>. 2(30. * Baly and Kirkes, op. cit., p. 57. 6 Traite de Physiologie, ii. 88, Paris, 1850. 454 GENERATION. considerable size; and pass so slowly through the stages of formation and decrease, that they are still perceptible at the end of pregnancy. They gradually diminish in size as the foetus becomes developed, and the term of gestation approaches. In an elaborate monograph, by Dr. Dalton,1 he confirms the views of Longet, and considers that whilst the statements of the latter are altogether under the form of general deductions, no series of observations having been given by him to establish a conviction of their reliability, he alone—so far as he is aware—has absolutely demonstrated the difference between the two species of corpora lutea by recorded facts. The difficulty of accurate decision in every case, however, is shown by a controversy between two distinguished observers and writers on this matter,—Dr. R. Paterson, and Dr. Robert Lee. Dr. Paterson2 had described what he conceived to be an early corpus luteum. This was designated by Dr. Lee, in his lectures, as a mere clot of blood; and he afterwards affirmed, that " the said clot oi blood did not present one of the characters of a true corpus luteum;" and that if he "was summoned into a court of justice, he would have no hesitation in declaring upon oath, from the evidence furnished, that the proofs of pregnancy were wholly want- ing." Dissatisfied with these remarks, Dr. Paterson forwarded, through a friend, the specimen in question, without stating what it was, to obtain Dr. Lee's unbiassed opinion of it from personal inspection; when, after a careful examination, Dr. Lee returned an answer, declar- ing it to be an early true corpus luteum, and requested permission to % describe it as such before the Royal Medico-Chirurgical Society of London !3 In regard to the offices performed by corpora lutea, difference of sentiment has existed, and still exists: Sir Everard Home—as has been seen—adopts the opinion of Vallisnieri, that they are glandular formations concerned in the production of ova. Others have supposed, that they furnish the ovum with the first materials that are needed for its developement.4 The generality of physiologists, perhaps, regard them as the result of a simple process of cicatrization set up in the emptied vesicle,—a process, which, according to Bischoff,5 bears the greatest analogy to that of the closure and healing of an abscess. c. Theories of Generation. We have now endeavoured to demonstrate the part performed by the two sexes in fecundation. It has been seen, that the material fur- nished by the male is sperm; that afforded by the female an ovum. The most difficult topic of inquiry yet remains,—how the new indi- vidual results from their commixture ? Of the nature of this myste- rious process we are profoundly ignorant; and if we could make any comparison between the extent of our ignorance of the different vital phenomena, we should be disposed* to decide, that the function of generation is one of the least intelligible. The new being must be 1 Op. cit., p. 642. 2 Edinb. Med. and Surg. Journ., No. 142. 3 R. Paterson, in Edinb. Med. and Surg. Journ., Oct., 1844, p. 467. 4 Montgomery, On the Signs and Symptoms of Pregnancy, &c, Amer. Med. Libr. edit., p. 149, Philad., 1839. 5 Developpement de l'Homme, &c, traduit par Jourdan, p. 44, Paris, 1843. THEORIES—EPIGENESIS. 455 stamped instantaneously as by a die. From the very moment of the admixture of the materials at a fecundating copulation, the embryo must have within it the powers necessary for its own formation,—im- pulses communicated by each parent, as regards likeness, hereditary predisposition, &c. From that moment the father has no communica- tion with it; yet we know, that it may resemble him in its features and predispositions to certain morbid states,—whilst the mother pro- bably exerts but a slight and indirect control over it afterwards; her office being chiefly to furnish the homunculus with a nidus, in which it may work its own formation, and with the necessary pabu- lum. We have seen, that even so early as the seventh and eighth day after fecundation, two projecting points—it has been asserted—have been observed in the ovum, which indicate the future situations of the brain and spinal marrow. [?] Our want of acquaintance with the pre- cise character of this impenetrable mystery will not, however, excuse us from passing over some of the ingenious hypotheses, that have been entertained. These have varied according to the views that prevailed respecting the nature of the sperm; and to the opinions indulged re- garding the matter furnished by the ovary. Drelincourt,1 who died in 1697, collected as many as two hundred and sixty hypotheses of generation; but they may all, perhaps, be classed under two,—the sys- tem of epigenesis and that of evolution. 1. Epigenesis.—According to this system, which is the most ancient of all, the new being is conceived to be built of materials furnished by both sexes, the particles composing those materials having pre- viously possessed the arrangement necessary for constituting it,—or having suddenly received such arrangement. Still, it is requisite that these particles should have some controlling force to regulate their affinity, different from* the ordinary forces of matter; and hence one has been imagined to exist, which has been termed cosmic, plastic, essential, nisus formativus—B ildungstrieb, of the Germans—force of formations, &c. Hippocrates2 maintains, that each of the two sexes possesses two kinds of seed, formed by the superfluous nutriment, and by fluids con- stituted of materials proceeding from all parts of the body, and espe- cially from the most essential,—the nervous. Of these two seeds, the stronger begets males, the weaker females. In the act of generation, these seeds are commingled in the uterus; and through the influence of the heat of that organ, they form the new individual—by a kind of animal crystallization—male or female, according to the predominance of the stronger or the weaker seed. Aristotle3 thought, that it is not by seed that the female participates in generation, but by menstrual blood. This he conceived is the basis of the new individual, whilst the principles furnished by the male communicate to it the vital move- ment, and fashion it. Empedocles, Epicurus, and various other ancient physiologists, contended, that the male and female respectively contri- bute a seminal fluid, which co-operate equally in the generation and developement of the foetus; and that it belongs to the male or female 1 Novem Libelli de Utero, Coneeptione, Footu, &c, Lugd. Bat., 1632. 2 nsji yov«c; in Oper. Omnia, edit. A. Foesio. Genev., 1657-1662. 3 De Generatione Animalium, &c, i. 19. 456 GENERATION. sex, or resembles more closely the father or the mother, according as the orgasm of the one or the other predominates, or is accompanied by a more copious emission. " Semper enim partus duplici de semine constat; Atque utrique simile est magis id quodcumque creatur." Luceet., lib. iv. Lactantius, on quoting the views of Aristotle, fancifully affirms, that the right side of the uterus is the proper chamber for the male fetus* the left for the female,—a belief, which appears to be still prevalent amongst the vulgar in many parts of Great Britain. But he adds; if the male or stronger semen should, by mischance, enter the left side of the uterus, a male child may still be conceived ; yet, as it occupies the female department, its voice, face, &c, will be effeminate. On the con- trary, if the weaker or female seed should flow into the right side of the uterus, and a female foetus be engendered, it will exhibit evidences of a masculine character. The idea of Aristotle with regard to the menstrual blood has met with few partisans, and is undeserving of farther notice. That of Hip- pocrates, notwithstanding the objections,—that the female furnishes no sperm, and the ovaria are in no respect analogous to the testes,—has had numerous supporters amongst the moderns, modified, however, to suit the scientific ideas of the time, and the individual. Des Cartes, for example, considered the new being to arise from a kind of fermenta- tion of the seed furnished by both sexes. Pascal, that the sperm of the male is acid; that of the female alkaline; and that they combine to form the embryo. Maupertius1 maintained, that, in each seed parts exist adapted for the formation of every organ of the body, and that, at the time of the union of the seed in a fecundating copulation, each of the parts is properly attracted and aggregated by a kind of crystal- lization.2 The celebrated hypothesis of the eloquent and enthusiastic Buffon3 is but a modification of the Hippocratic doctrinei of epigenesis. Ac- cording to him, there exist in nature two kinds of matter,—living and dead; the former perpetually changing during life, and consisting of an infinite number of small, incorruptible particles or primordial monads, which he called organic molecules. These molecules, by com- bining in greater or less quantity with dead matter, form all organized bodies; and without undergoing destruction are incessantly passing from vegetables to animals in the nutrition of the latter, and are re- turned from the animal to the vegetable by the death and putrefaction of the former. These organic molecules, during the period of growth, are appropriated to the developement of the individual; but as soon as he has acquired his full size the superfluous molecules are sent into depot in the genital organs, each molecule being invested with the shape of the part sending it. In this way, he conceived, the seed of both sexes is formed of molecules obtained from every part of the sys- tem. In the commixture of the seeds during a fecundating copulation, 1 Vi'nus Physique, Paris, 1751. 2 Adelon, Physiologie de l'Homme, iv. 85, 2de edit., Paris, 1829. 3 Histoire Naturelle, torn, xvii., &c, Paris, 1799. THEORIES—EPIGENESIS. 457 the same force that assimilates the organic molecules to the parts of the body for their nourishment and increase causes them to congregate for the formation of the new individual; and according as the mole- cules of the male or female predominate, so is the embryo male or female. The ingenuity of this doctrine was captivating; and it appeared so well adapted for the explanation of many of the phenomena of genera- tion, that it had numerous and respectable votaries. It accounted for the circumstance of procreation not being practicable until the s}7stem has undergone its developement at puberty. It explained why excess- ive indulgence in venery occasions emaciation and exhaustion; and why, on the other hand, the castrated animal is disposed to obesity,—■ the depot having been removed by the mutilation. The resemblance of the child to one parent rather than to the other was supposed to be owing to the one furnishing a greater proportion of organic molecules than the other; and as more males than females are born, the circum- stance was ascribed to the male being usually stronger, and therefore furnishing a stronger seed, or more of it. Prior to this hypothesis, Leeuenhoek1 had discovered what he con- sidered to be spermatic animalcules in the semen; but Buffon contested their animalcular nature, and regarded them as his vital particles or organic molecules; whilst he looked upon the ovarian vesicle as the capsule that contains the sperm of the female. The opinions of Buffon were slightly modified by Blumenbach2 and Darwin.3 The former, like Buffon, divided matter into two kinds, possessing properties essentially different from each other;—the inorganic and the organized; the latter possessing a peculiar creative or formative impulse, which he termed Bildungstrieb or nisusformativus,—a principle in many respects resembling gravitation, and endowing every organized tissue with a vita propria. This force, he conceived, presides over the arrangement of materials furnished by the sexes in generation. Darwin preferred to the term "organic molecules" that of vital germs, which, he main- tains, are of two kinds, according as they are secreted or provided by male or female organs, whether animal or vegetable. In the subdivi- sion, however, of the germs he retained the term molecule; but limited it to those of the female;—the vital germs or particles, secreted by the female organs of a bud or flower, or the female particles of an animal, being denominated by him molecules with formative propensities; whilst those secreted from the male organs he termed fibrils with forma- tive appetencies. To the fibrils he assigned a higher degree of organi- zation than to the molecules. Both, however, have a propensity or appetency to form or create, and "they reciprocally stimulate and em- brace each other and instantly coalesce; and may thus be popularly compared to the double affinities of chemistry." Subtile as are these hypotheses, they are open to forcible objections, of which a few only will suffice. The notion of this occult force is identical with that, which has prevailed in regard to life in general, 1 Arcana Naturae, Lugd. Bat., 1685. 2 Ueber den Bildungstrieb, Getting., 1791; Comment. Societat. Gotting., torn. viii.; and Institutiones Physiologies, sect. xl. p. 459. Gotting., 1798. 8 Zoonomia, vol. ii. sect, xxxix., 8, 10, 3d edit., London, 1801. 458 GENERATION. and leaves the subject in the same obscurity. What do the terms plastic, cosmic, or vegetative force, or Bildungstrieb express, which is not equally conveyed by vital force,—that mysterious power, on which so many unfathomable processes of the animal body are depend- ent, and of the nature or essence of which we know absolutely nothing? The objection, urged against the doctrine of Hippocrates,—that we have no evidence of the existence of female sperm,—applies equally to the hypotheses that have been founded upon it; and even were we to grant, that the ovarium is a receptacle for female sperm, the idea that such sperm is constituted of organic molecules derived from every part of the body would still be gratuitous. We have no facts to de- monstrate the affirmative; whilst there are many circumstances, that favour the negative. A person, for example, who has lost some part of his person—nose, eye, or ear, or has had a limb amputated, or been circumcised—still begets perfect children. Whence can the molecules in such cases, have been obtained ? It is true, that if the mutilation affect but one parent, the organic molecules of the lost part may still exist in the seed of the other; but we ought, at least, to expect the part to be less perfectly formed; which is not the case. Where two docked horses are made to engender, the. result ought, d fortiori, to be imperfect, as the organic molecules of the tail could not be furnished by either parent, yet we find the colt in such cases, perfect in this appendage. An elucidative case is afforded by the foetus. If we admit the possibility of organic molecules constituting those parts that exist in the parents, how can we account for the formation of such as are peculiar to fcetal existence? Whence are the organic molecules of the umbilical cord, or umbilical vein, or ductus venosus, or ductus arteriosus, or umbilical arteries obtained ? These and other objections have led to the abandonment of the theory of Buffon, which remains a monument of the author's ingenuity and elevation of fancy, —not of his solidity. 2. Evolution.—According to this theory, the new being pre-exists in some shape in one sex, but requires to be vivified by the other in the act of generation; after which it commences a series of develope- ments or evolutions, which lead to the formation of an independent being. The great differences of sentiment that have prevailed under this view have been as regards the part, which each sex has been conceived to play in the function. Some have considered the germ to exist in the ovary, and to require the vivifying influence of the male sperm to cause its evolution. Others have conceived the male sperm to contain the rudiments of the new being, and the female to afford it merely a nidus, and pabulum during its developement. The former class of physiologists have been called ovarists or ovists;—the latter spermatists, seminists, and animalculists. The ovarists maintain, that the part furnished by the female is an ovarian ovum, which, they con- ceive, is formed of an embryo and particular organs for its nutrition and first developement;—the embryo adapted for becoming, after a series of changes or evolutions, a being similar to the one whence it has emanated. This hypothesis was suggested by the fact, that in many animals a single individual only is necessary for reproduction, and its being easier, perhaps, to conceive this individual to be female than THEORIES—EVOLUTION. 459 male; as well as by what is noticed in many oviparous animals. In them, the part, furnished by the female, is manifestly an ovum or egg; and in many, such egg is laid before the union of the sexes; and fecundated externally. By analogy, the inference was drawn, that this may happen to the viviparous animal likewise. The notion is said, but erroneously, to have been first advanced by Joseph de Aromatariis.1 It was developed by Harvey,2 who strenuously maintained the doctrine —omne vivum ex ovo. The anatomical examinations of Sylvius, Vesa- lius, Fallopius, De Graaf,3 Malpighi,4 Vallisnieri5 and others,—by show- ing, that what had been previously regarded as female testes, and had been so called, were organs containing minute vesicles or ova, and hence termed by Steno ovaria,—were strong confirmations of this view, and startling objections to the ancient theory of epigenesis; and the problem appeared to be demonstrated, when it was discovered, that the vesicle or ovum leaves the ovary and passes through the Fallopian tube to the uterus. The chief arguments that have been adduced in favour of the doctrine are:—First. The difficulty of conceiving the formation, ab origine, of an organized body, as no one part can exist without the simultaneous exist- ence of others. Secondly. The presence of the germ in many living beings prior to fecundation. In plants, for example, the grain exists in a rudimental state in the flower, before the pollen, which has to fecundate it, has attained maturity. In birds, too, the egg must pre- exist, as we find that those, which have never had intercourse with the male, can lay. This is more strikingly manifest in many fishes, and in the batracia or frog kind, where the egg is not fecundated until after it has been extruded. Spallanzani, moreover, asserts, that he could distinguish the presence of the tadpole in the unfecundated ova of the frog; and Haller, that of the chick in the infecund egg: he has seen them containing the yolk, which, in his view, is but a dependence of the intestine of the foetus, and if the yolk exist, the chick, he argues, must exist also.[!] Thirdly. The fact, before referred to, that in certain animals, a single copulation is capable of fecundating several successive generations. In these cases, it is argued, the germ of the different generations must have existed in the first. Fourthly. The fact of natural and accidental encasings, inclusions or emboitements,—as in the bulb of the hyacinth, in which the rudiments of the flower are distinguishable; in the buds of trees, in which the branches, leaves, and flowers, have been detected in miniature, and greatly convoluted; in the jaws of cer- tain animals, in which the germs of different series of teeth can be de- tected ; in the volvox, a transparent animal, which exhibits several young encased in each other; in the common egg, which occasionally has another within it; and in the instances on record, in which a human foetus has been found encased—foetus in fcetu—many cases of which are referred to by Professor Vrolik ;6 and of which there is a striking 1 Epist. de Generatione Plantarum ex Seminibus, Venet., 1625. 2 Kxercitationes de Generatione Animalium, Lond., 1651. 3 De Organis Mulierum, &o., Lugd. Bat., 1672. 4 Append, ad Opera Omnia, Ludg. Bat., 1687. 6 Istoria della Generazione dell'Uomo, Discorsi Acad, i.-iv., Venez., 1722-1726. 6 Art. Teratology, in Cyclopaedia of Anat. and Physiology, iv. 967, London, 1852. 460 GENERATION. example in a youth in the Museum of the Royal College of Surgeons of London; and a similar one, in a boy fourteen years of age, has been recorded by Dupuytren. A most singular case of the kind occurred to M. Velpeau.1 A tumour was removed from the scrotum of a young man aged 27, which was found to contain almost all the elements of a human body. Its exterior was evidently tegumentary, and the greater part of its substance, a mixture of lamellae and fibres like areolar, adipous, muscular, and fibrous tissues. In the interior, there were two cysts filled with a substance like albumen or the vitreous humour; another cyst, as large as a partridge's egg, containing a greenish semi- fluid matter like meconium; and a fourth contained a dirty yellow grumous mass surrounded by hairs: the mass consisted of sebaceous matter and scales of epidermis; the hairs had no bulbs. A tuft of hair, which protruded externally from a kind of ulcer at the posterior part, —and which, with the fact of the tumor being congenital, induced M. Velpeau to consider it to be fcetal,—proceeded from the cyst that con- tained the meconium-like substance, and gave the opening into it somewhat the appearance of an anus. In the midst of all these, numer- ous perfectly organized portions of a skeleton were found, consisting of bones resembling more or less the clavicle, scapula, humerus, sphe- noid bone, sacrum, portions of vertebrae, and others whose names could not be determined. A peculiarity of this case of monstrosity by in- clusion was, that the second foetus did not act as a foreign body in the other, but had a separate and independent existence and power of growth within itself. The tumour had its own colour and consistence, and a sensibility entirely independent of the person to whom it was attached. The man himself pierced it several times with a knife with- out feeling the least pain; and yet, all the wounds that were made in it bled, inflamed and cicatrized like those of any other part of the body. Perhaps, the explanation of these extraordinary cases by Dr. Blun- dell2 is as philosophical as any that could be devised. A seed or egg, though fecundated, may lie for years without being evolved. A ser- pent may become enclosed under the eggshell of the goose; the shell probably forming over it as the animal lies in the oviduct of the bird. These facts Dr. Blundell applies to the phenomenon in question. When the boy was begotten, a twin was begotten at the same time,—but, while the former underwent his developement in the usual manner, the impregnated ovum of his companion lay dormant, and unresistingly became closed up within the fraternal structure, as the viper in the eggshell. For a few years, these living rudiments generally lie quiet within the body, and ultimately become developed so as to occasion the death of both. " The boy," he remarks—speaking of one of the cases—"became pregnant with his twin brother; his abdomen formed the receptacle, where, as in the nest of a bird, the formation was ac- complished." Cases of this kind of arrest of developement occasion- ally occur, where two or more ova are fecundated at the same time, or in succession. To this we shall refer under Superfcetation. Fifthly. 1 Gazette Medicale, 15 Fev., 1840. 2 Principles and Practice of Obstetricy, edited by Dr. Castle, London, 1834; Ameri- can edition, Washington. ' THEORIES—EVOLUTION. 461 * The fact of the various metamorphoses that take place in certain ani- mals. Of these we have the most familiar instances in the batracia, and in insects. The forms which they have successively to assume are evidently encased within each other. In the chrysalis, the outlines of the form of the future butterfly are apparent; and in the larva we observe those of the chrysalis. The frog is apparent under the skin of the tadpole. Sixthly. The fact of artificial fecundation, which has been regarded by the ovarists as one of the strongest proofs of their theory;—the quantity of sperm employed, as in the experiments of Spallanzani already detailed, being too small, in their opinion, to assist in the formation of the new individual, except as a vivifying material. Lastly. They invoke the circumstance of partial reproduction, of which all living bodies afford more or less manifest examples;—as that of the hair and nails of man; the teeth of the rodentia; the tail of the lizard ; the claw of the lobster; the head of the snail, &c, &c. All these phe- nomena, according to them, are owing to each part possessing within itself germs destined for its reproduction; and requiring only favoura- ble circumstances for their developement. The partisans of the doc- trine of epigenesis, however, consider these last facts as opposed to the views of the ovarists; and maintain, that, in such cases, there is throughout a fresh formation. The chief objections, that have been urged against the hypothesis of the ovarists, are:—First. The resemblance of the child to the father —a subject to be referred to presently. The ovarists cannot of course deny that such resemblance exists; and they ascribe it to the modify- ing influence exerted by the male sperm; but without being able to explain the nature of such influence. They affirm, however, that the likeness to the mother is more frequent and evident. But certain cases of resemblance are weighty stumbling-blocks to ovism or the doctrine of a pre-existing germ in the female. It is a well-known fact, that six-fingered men occasionally beget six-fingered children. How can we explain this upon the principle of the pre-existence of the germ in the female, and of the part played by the male sperm being simply that of vivifying? and must we suppose, in the case of monstrosities, that such germs were originally monstrous ? Secondly. The produc- tion of hybrids is one of the strongest counter-arguments. They are produced by the union of the male and female of different species. Of these, the mule is the most familiar instance,—the product "of the ass and the mare. It strikingly participates in the qualities of both parents; and, consequently, the pre-existing germ in the female must have been more than vivified by the sexual intercourse. Its structure must have been altogether changed, and all the germs of its future offspring annihilated, for the mule is seldom fertile. If a white woman marries a negro, the child is a mulatto; and if the successive genera- tions of this be united to negroes, the progeny will ultimately become entirely black; or, at least, the white admixture will be so small as to escape recognition. As a general rule, the offspring of different races has an intermediate tint between that of the parents. The proportions of white and black blood, in different admixtures, have even been sub- jected to calculation, in countries where negroes are common. The • 462 GENERATION. following table represents these proportions, according to principles sanctioned by custom :— Parents. Negro and white, White and mulatto, Negro and mulatto, White and terceron, Negro and terceron, White and quarteron Negro and quarteron, Offspring. mulatto, terceron, f griffo, griff, or zambo,) { or black terceron, j quarteron, quadroon, black quarteron or quadroon, quinteron, black quinteron, Degrees of Mixture. £ white, J black. I - i - i - f - * - * - If rV The last two, in the British West India Islands,1 are considered to be respectively white and black; and the former were white by law, and consequently free, when slavery existed there. The following table is given by Tschudi2 to exhibit the parentage of the different varieties of half casts, and their proper designations:— White father and negro mother, White father and Indian mother, Indian father and negro mother, White father and mulatto mother, White father and mestiza mother, 1 White father and China mother, White father and cuarterona mother, White father and quintera mother, Negro father and mulatto mother, Negro father and mestiza mother, Negro father and China mother, Negro father and zamba mother, Negro father and cuarterona or quintera mother, Indian father and mulatto mother, Indian father and mestiza mother, Indian father and China mother, Indian father and zamba mother, Indian father and China-chola mother, Indian father and cuarterona or quintera mother. Mulatto father and zamba mother, Mulatto father and mestiza mother, Mulatto father and China mother, Children. mulatto. mestizo. Chino. cuarteron. Creole (only distinguished from the white by a pale brownish com- plexion). Chino-blanco. quintero. white. zambo-negro. mulatto-oscuro. zambo-Chino. zambo-negro (perfectly black). mulatto (rather dark). Chino-oscuro. mestizo-claro (frequently very beau- tiful). Chino-cholo. zambo-claro. Indian (with rather short frizzy hair). mestizo (rather brown). zambo (a miserable race). Chino (of rather clear complexion). Chino (rather dark). All these cases exhibit the influence exerted by the father upon the character of the offspring, and are great difficulties in the way of sup- posing, that the male sperm is simply a vivifier of the germ pre-existing in the female. Thirdly. The doctrine of the ovarists does not account for the greater degree of fertility of cultivated plants and domesticated ani- mals. Fourthly. The changes, induced by the succession of ages on the animal and vegetable species inhabiting the surface of the globe, have been adduced against this hypothesis. In examining the geologi- cal character of the various strata that compose the earth, it has been 1 Lawrence, Lectures on Physiology, Zoology, and Natural History of Man, p. 299, Lond., 1819. 2 Travels in Peru, during the years 1838-1842; translated from the German by Thomasine Ross, Amer. edit., p. 81, New York, lb47. THEORIES — EVOLUTION. 463 observed by geologists, that many of these contain embedded the fossil remains of animals and vegetables. Now the rocks on which others rest are the oldest, and the successive strata above these are more and more modern; and it has been found, that the organic fossil remains in the different strata differ more and more from the present inhabitants of the surface of the globe in proportion to the depth we descend ; and that the remains of those beings, that have always been the companions of man, are found only in the most recent of the alluvial deposits,—the upper crust of the earth. It was an opinion, at one time universally embraced, that geological evidence is in favour of animals having been created in the order of their relative perfection, so that the lowest animals; as the polyps and echinoderms occupied the most ancient formations; and to these succeeded the mollusks; then the articulated animals, and, lastly, the vertebrate. More recent investigation has, however, satisfied the geologist, that fossils, belonging to each of the four departments, have been found in the fossiliferous deposits of every age. Four ages of nature, according to Professor Agassiz,1 may be distinguished, which correspond with the great geological divisions. First. The Primary or Paleozoic age, comprising the lower Silurian, the upper Silurian, and the Devonian; during which there were no air- breathing animals. Fishes were the masters of creation, and hence—it has been suggested—this may be called the Reign of Fishes. Secondly. The secondary age, comprising the carboniferous formation, the trias, the oolitic, and the cretaceous formations, in which air-breathing ani- mals first appear; and as the reptiles predominate over the other classes, this has been termed the Reign of Reptiles. Thirdly. The Tertiary age, comprising the tertiary formations, during which terres- trial mammals of great size abounded. This was the Reign of Mam- mals; and Fourthly; the Modern age, characterized by the appearance of the most perfect of all created beings. This has been called the Reign of Man. In the older rocks the impressions are chiefly of the less perfect plants, and of the lower animals. In the more recent strata, the remains of reptiles, birds, and quadrupeds are apparent; but they differ essen- tially from existing kinds, and in none of the formations of more ancient date has the fossil human skeleton been met with. The skeleton of the savage Galibi, from Guadaloupe deposited in the British Museum, is em- bedded in a calcareous earth of modern formation; and the pretended human bones, conveyed by Spallanzani from the Island of Cerigo—the ancient Cythera—are not those of the human species, any more than the bones of the Homo diluvii testis of Scheuchzer. Hence it has been concluded, that man is of a date posterior to animals in all countries where fossil bones have been discovered. It has been attempted to ex- plain these singular facts, furnished by modern geological inquiry, by the supposition, that the present races of animals are the descendants of those whose remains are met with in the rocks, and that their difference of character may have arisen from some change in the physical consti- tution of the atmosphere, or of the surface of the earth, producing a corresponding change in the forms of organized beings. It has been ' Agassiz and Gould, Principles of Zoology, p. 190, Boston, 1848. 464 GENERATION. properly remarked, however, by Dr. Fleming,1 that the effect of cir- cumstances on the appearance of living beings is circumscribed within certain limits, so that no transmutation of species was ever ascertained to have taken place, whilst the fossil species differ as much from the recent kinds as the last do from each other; and he adds, that it re- mains for the abettors of the opinion to connect the extinct with the living races, by ascertaining the intermediate links or transitions. This will probably never be practicable. The difference, indeed, be- tween the extinct and living races is in several cases so extreme, that many naturalists have preferred believing in the occasional formation of new organized beings. Linnseus was bold enough to affirm, that in his time, more species of vegetables were in existence than in former periods, and hence, that new vegetable species must necessarily have been ushered into being; and Wildenow embraced the views of Lin- naeus. De Lamarck,2 one of the most distinguished naturalists of his day, openly professed the belief, that both animals and vegetables are incessantly changing under the influence of climate, food, domesti- cation, crossing of breeds, &c, and he remarks, that if the species now in existence appear to us fixed in their characters, it is because the modifying circumstances require an enormous time for action, and would, consequently, require numerous generations to establish the fact. The manifest effect of climate, food, &c, on vegetables and ani- mals, he thinks, precludes the possibility of denying those changes on theoretical considerations; and what we call lost species are, in his view, the actual species before they experienced modification. It is proper, however, to observe, that the representations on the wall of one of the sepulchres in the valley of Beban el Molook, at Thebes, which are re- garded by Champollion as having been executed upwards of two thou- sand years before the Christian era, enable the features of the Jew and the negro, amongst others, to be recognized as easily as the represen- tations of their descendants of the present day; so that, for the space of at least three thousand eight hundred years, no modification of the kind referred to by De Lamarck seems to have occurred in the human species.3 Another explanation has been offered for these geological facts, and for the rotation, which we observe in the vegetable occupants of par- ticular soils in successive years. It has been supposed, that as the seeds of plants and the ova of certain animals are so excessively minute as to penetrate wherever water or air can enter; and as they are capable of retaining the vital principle for an indefinite length of time, of which we have many proofs, and of undergoing evolution whenever circum- stances are favourable, the crust of the earth may be regarded as a receptacle of germs, each of which is ready to expand into vegetable or animal forms, on the occurrence of conditions necessary for their 1 Philosophy of Zoology i. 26, Edinb., 1822. 2 Philosophie Zoologique, edit, cit., torn, i., p. 218, Paris, 1830. 3 " Nous avons sous les yeux des Momies Humaines; le squelette de I'homme d'au- jourdhui est le meme, absolument le meme que le squelette de I'homme de 1'antique Egypte. Ainsi done, depuis deux ou trois mille ans, depuis les observations d'Aristote depuis les momies conservees d'Egypte, aucune espece n'a changeV' Flourens, De la Longevite Humaine et de la Quantite de Vie sur le Globe, 2de e"dit.,p. 143, Paris, 1855. THEORIES—EVOLUTION. 465 developement.. This is the hypothesis of panspermia or dissemination of germs, according to which the germs of the ferns and reeds were first expanded, and afterwards those of the staminiferous or more perfect vegetables; and, in the animal kingdom, first the polyp, and gradually the being more elevated in the scale; the organized bodies of the first period flourishing, so long as the circumstances favourable to their developement continued, and then making way for the evolution of their successors,—the changes effected in the soil by the growth and decay of the former probably favouring the evolution of the latter; which, again, retained possession of the soil so long as circumstances were propitious.1 The changes that take place in forest vegetation are favourable to this doctrine. If, in Virginia, the forest trees be removed so as to make way for other growth, and the ground be prepared for the first cultivation, the Phytolacca decandra or poke, which was not previously perceptible on the land, usurps the surface. When Mr. Madison went with General Lafayette to the Indian treaty, they dis- covered, wherever trees had been blown down by a hurricane in the spring, that white clover had sprung up in abundance, although the spot was many miles distant from any cleared land ; and it has often been remarked, that where, during a drought in the spring, the woods have taken fire, and the surface of the ground has been torrefied, the water-weed has made its appearance in immense quantities, and occu- pied the burnt surface. The late Judge Peters, having occasion to cut ditches on his land, in the western part of Pennsylvania, was surprised to find every subterranean tree met with differing from those occupy- ing the surface at the time; and President Madison informed the author, that, in the space of sixty or seventy years, he had noticed the follow- ing spontaneous rotation of vegetables:—1. Mayweed; 2. Blue cen- taury; 3. Bottle-brush-grass; 4. Broom-straw; 5. White clover; 6. Wild carrot; and the last was then giving way to the blue grass. The doctrine of panspermia is, however, totally inapplicable to the viviparous animal, in which the ovum is hatched within the body, and which, consequently, continues to live after the birth of its progeny; and the facts furnished by geology seem clearly to show, that the developement of the animal kingdom has been successive, not simul- taneous ; but under what circumstances the different animals were suc- cessively ushered into being, we know not. Lastly, as regards the ovarists themselves;—they differ in essential points: whilst some are favourable to the doctrine of the dissemination of germs, believing, as we have seen, that ova or germs are dissemi- nated over all space, and that they only undergo developement under favourable circumstances,—as when they meet with bodies capable of retaining them, and causing their growth, or which resemble them- selves,—others assert, that the germs are enclosed in each other, and are successively aroused from their torpor, and called into life, by the influence of the seminal fluid; so that not only did the ovary of the first female contain the ova of all the children she had, but one only of these ova contained the whole of the human race. This was the celebrated system of emboitement des germes or encasing of germs, already vol. ii.—30 1 Fleming, op. citat., i. 28. 466 GENERATION. referred to, of which Bonnet1 was the propounder, and Spallanzani the promulgator. Yet how monstrous for us to believe, that the first female had within her the germs of all mankind born, and to be born * or to conceive, that a grain of Indian corn contains within it all the seed, that may hereafter result from its culture. In this strange hypo- thesis—as Professor Blliotson2 observes—there must have been an uncommon store of germs prepared at the beginning, for the ovaria of a single sturgeon have contained 1,467,500 ova. Many of the ovarists, again, and they alone have any thing like probability in their favour, believe, that the female forms her own ova, as the male forms his own sperm, by a secretory action; and so far as the female is concerned in the generative process, we shall find that this is the only philosophical view; but it is imperfect in not ad- mitting more than a vivifying action in the materials furnished by the male. The view formerly advanced by Bischoff,3—who now admits the positive entrance of the spermatozoid into the ovum4—that the spermatozoids act in a catalytic manner,—a certain internal movement being transferred from them to the molecules of the ova, which previously remained dormant,—appears to be liable to the same ob- jections. About the middle of the seventeenth century, Hamme or Van Ham- men, Leeuenhoek5 and Hartsoker,8 discovered a prodigious number of small moving bodies in the sperm of animals, which they regarded as animalcules. This gave rise to a new system of generation, ab ani- malculo maris,—directly the reverse of that of Harvey. As, in the Harveian doctrine, the germ was conceived to be furnished by the mother, and the vivifying influence to be alone exerted by the male; so, in this doctrine, the entire formation was regarded as the work of the father, the mother affording nothing more than a nidus, and ap- propriate pabulum for the homunculus or rudimental foetus. The spermatic doctrine was soon embraced by Boerhaave, Keill, Cheyne, Wolff, Lieutaud, and others. The pre-existing germ was accordingly now referred exclusively to the male; and, by some, the doctrine of emboitement or encasing was extended to it. Nor is the view aban- doned at the present day; for a recent writer7 has maintained, that "the male furnishes the germ; and the female supplies it with nutri- ment, during the whole period of its early developement." In support of this hypothesis, the spermatists urged,—that the animalcules they discovered were peculiar to the semen, and that they exist in the sperm of all animals capable of generation; that they differ in different species, but are always identical in the same animal, and in individuals of the same species;—that they are not perceptible in the sperm of any animal until the age at which generation is prac- ticable, and are wanting in infancy and decrepitude;—that their num- ber is so considerable, that a drop of the sperm of a cock, scarcely 1 Considerat. sur les Corps Organises, Amst., 1762. 2 Blumenbach's Physiology, by Elliotson, 4th edit., p. 494, Lond., 1828. 3 Muller's Archiv. fiir Anat., No. v. S. 436, Berlin, 1847. 4 Page 438. 6 Oper., iii. 285, and iv. 169, Lugd. Bat., 1722. 6 Journal des Scavans, pour 1678 ; and Essai de Dioptrique, p. 227, Paris, 1694. 7 Carpenter, Principles of Human Physiology, 4th Amer. edit., p. 720, Philad., 1850. THEORIES—EVOLUTION. 467 equal in size to a grain of sand, contains 50,000;—and lastly, that their minute size is no obstacle to the supposition, that generation is accomplished by them,—the disproportion between the trees of our forest and the seed producing them being nearly, if not entirely, as great as that between the animalcule and the being it has to develope. Leeuenhoek estimated the dimensions of those of the frog at about the l-10,000th part of a human hair, and that the milt of a cod may con- tain 15,000,000,000,000,000 of them. The difficulty with the spermatists or animalculists was to determine the mode in which the homunculus attains the ovary, and effects the work of reproduction. Whilst some asserted it to be only requisite, that the sperm should enter the uterus, and attract the ovum to it from the ovarium; others imagined, that the animalcule travelled along the Fallopian tube to the ovary; entered one of the ovarian vesicles; shut itself up there for some time, and then returned into the cavity of the uterus, to undergo its first developement through the medium of the nutritive substance contained in the vesicle; and a celebrated pupil of Leeuenhoek even affirmed, that he not only saw these animalcules under the shape of the tadpole, as they were generally described, but that he could trace one of them, bursting through the envelope that retained it, and exhibiting two arms, two legs, a human head and a heart I1 This doctrine was extremely captivating; and, for a time, kept the minds of many eminent philosophers in a state of delusive enthusiasm; so much so, that Dr. Thomas Morgan,2 in a work published in 1731, thus expresses himself regarding it:—" That all generation is from animalculum pre-existing in semine maris, is so evident in fact, and so well confirmed by experience and observation, that I know of no learned men, who in the least doubt of it." It was soon, however, strongly objected to by many; and the great fact on which it rested—the very existence of spermatic animalcules was, and—we have seen—is, strenu- ously contested. Linnaeus3 discredited the observations of Leeuenhoek. Verheyen denied the existence of the animalcules, and undertook to demonstrate, that the motion, supposed to be traced in them, was a mere microscopic delusion:—whilst Needham4 and Buffon regarded them as organic molecules. Subsequently, MM. Prevost and Dumas3 directed their attention to the subject; and their investigations, as on every other topic of physiological inquiry, are worthy of the deepest regard. The results of their examinations led them to confirm the existence of these animalcules, and likewise to consider them as direct agents in fecundation. By means of the microscope they detected them in all the animals, whose sperm was examined by them; and these were numerous. Whether the fluid was observed after its excretion by a living animal, or after death, in the vas deferens or the testicle, animalcules were detected in it with equal facility. They consider 1 Adelon, Physiologie de l'Homme, edit, cit., iv. 94. * Mechanical Practice of Physic, Lond., 1731. 3 Bostock's Physiology, 3d edit., p. 643, Lond., 1836. 4 New Microscopical Discoveries, Lond., 1745. 6 Mem. de la Societe Physique de Geneve, i. 180, and Annales des Sciences Natu- relles, torn. i. and ii. 468 GENERATION. these bodies to be characteristic of the sperm, as they found them only in that secretion,—being wanting in every other humour of the body, even in those that are excreted with the sperm, as the fluids of the prostate, and glands of Cowper; and although similar in shape, and size, and in the character of their locomotion in individuals of the same species, they are of various shapes and dimensions in different species. In passing through the series of genital organs they expe- rience no change, being as perfect in the testicle as at the time of their excretion; and the remark of Leeuenhoek, that they are met with apparently of different ages, is unfounded. They were manifestly endowed with spontaneous motion, which gradually ceased, in the course of two or three hours, in the sperm obtained during life by ejaculation,—in that taken from the vessels after death, in fifteen or twenty minutes,—and in that left in its vessels after death, in eighteen or twenty hours. In farther proof of the position, that these presumed animalcules are the fecundating agents, MM. PreVost and Dumas assert, that they are only met with whilst reproduction is practicable;—that, in the human species, they are not found in infancy or decrepitude; and, in the majority of birds, are only apparent in the sperm at periods fixed for their copulation;—facts which, in their opinion, show, that they are not mere infusory animalcules. MM. PreVost and Dumas affirm, moreover, that they appear to be connected with the physiolo- gical condition of the animal furnishing them;—their motions being rapid or languishing, according as it is young or old, or in a state of health or disease. They state, also, that in their experiments on the ova of the mammiferous animal, they observed animalcules filling the cornua of the uterus, and remaining there alive and moving, until the ovule descended into that organ, when they gradually disappeared; and in favour of the influence of these animalcules they urge—that the positive contact of sperm is necessary for fecundation, and that the aura seminis is totally insufficient;—that the sperm, in twenty-four hours, loses its fecundating property, and it requires about this length of time for the animalcules to gradually cease their movements and perish;—and, lastly, that having destroyed the,animalcules in the sperm, it lost its fecundating property. One of these experiments consisted in killing all the animalcules in a spermatized fluid, whose fecundating power had been previously tested, by repeated discharges of a Leyden phial: another consisted in placing a spermatized fluid on a quintuple filter, and repeating this until all the animalcules were retained on the filter; when it was found, that the fluid that passed through had no fecundating power, whilst the portion retained by the filter had; a result which had been obtained by Spallanzani, who found, moreover, that he was capable of effecting fecundation with water in which the papers employed as filters had been washed. M. Donne"1 has investigated the mode in which the zoospermes are affected in blood, milk, the vaginal and uterine mucus in the healthy state, the purulent matter of chancres, and of blennorrhcea, in saliva, urine, &c. He observed them continue to live, and move in certain of those fluids; whilst in others they died instantaneously. For instance, 1 Gazette Medicale de Paris, No. xxii., 3 Juin, 1837; and Cours de Microscopie, p. 291, Paris, 1845. THEORIES—EVOLUTION. 469 blood, milk and pus did not affect them: in the mucus of the vagina and uterus they generally lived well; but in saliva and urine they died almost instantaneously. He affirms, too, that there are cases in which the mucus of the vagina and uterus acquires properties that are dele- terious to them, and is of opinion, that this is one cause of sterility. This deleterious property, according to M. Donne', occasionally resides in the vaginal mucus; but at others, in a still higher degree, in the mucus of the uterus: he endeavoured to discover, whether the mucus of the two membranes presented any peculiar characters or signs of disease, and states, that he particularly noticed the excessive acidity of the one, and the marked alkaline character of the other. Independently of its physical characters, the mucus secreted by the vagina as far as the orifice of the os uteri differed from that which flowed from within the cervix uteri by a different reaction. He found the vaginal mucus always acid,—the uterine alkaline, and he thinks, that the deleterious influence exerted on the zoospermes is dependent on excess of acid in the one, and of alkali in the other. All this, however, it need scarcely be said, requires substantiation. Professor Wagner,1 who has entered at great length into the consideration of the spermatozoids, accords with the general conclusions of M. Donne': some of his experi- ments, however—instituted for the most part on the spermatozoids of the lower animals—led him to different conclusions. He found, for example, that they almost always lived in saliva; and in urine kept warm and not too concentrated. He repeatedly detected them in the urine of persons whom he suspected of masturbation. Dr. John Davy2 states, that on examining the fluid from the urethra after stool in a healthy man, he always detected spermatozoids in it; and Dr. Robt. Willis,3 under the same circumstances, and even after the mere evacua- tion of the bladder, several times discovered spermatozoids in the fluid of the urethra; but the subjects of his observations were never strong or healthy men: they mostly laboured under anomalous nervous symp- toms, which, he thinks, were in all likelihood connected with an irri- table or disordered state of the vesiculae seminales and prostatic part of the urethra. MM. Prevost and Dumas, and Rolando, conjecture, that the sperm- atozoids form the nervous system of the new being, and that the ovule furnishes only the areolar framework in which the organs are formed; but this is mere hypothesis. All that is demonstrated is the existence of those peculiar bodies in the sperm, and their manifest agency in the generative process; and it is scarcely necessary to remark, that every objection urged against the system of the ovarists, as regards the proofs in favour of an active participation of both sexes in the work of reproduction, are equally applicable to the views of those who refer generation exclusively to the spermatozoids.4 Such are the chief theories that have been propounded on the sub- ject of generation. It has been already observed, that the particular 1 Elements of Physiology, translated by Dr. Willis, p. 20, Lond., 1841. 2 Edinburgh Medical and Surgical Journal, vol. i. 3 Wagner, op. citat., p. 21 (note). 4 For a history of opinions in regard to the agency of the sperm, see Coste, Histoire Generale et Particuliere du Dcveloppement des Corps Organises, p. 335, Paris, 1849. 470 GENERATION. modifications are almost innumerable. They may all, however, be classed, with more or less consanguinity, under some of the doctrines enumerated. Facts and arguments are strongly against any view that refers the whole process of formation to either sex.1 There must be a union of materials furnished by both, otherwise it is impossible to ex- plain the similarity in conformation to both parents, which is often so manifest. Accordingly, this modified view of epigenesis is now adopted by most physiologists;—that at a fecundating copulation, the secretion of the male is united to a material, furnished by the ovary of the fe- male;—that from the union of these elements the embryo results, im- pressed, from the very instant of such union, with life, and with an impulse to a greater or less resemblance to this or that parent, as the case may be; and that the material furnished by the female is as much a secretion resulting from the peculiar organization of the ovary, as the sperm is from that of the testicle,—life being susceptible, in this manner, of communication from father to child, without there being a necessity for invoking the incomprehensible and revolting doctrine of the pre-existence of germs. This admixture of the materials furnished by both sexes accounts for the likeness that the child may bear to either parent, whatever may be the difficulty in understanding the precise mode in which each acts in the formation of the foetus. It has been attempted, however, by some, to maintain, that the influence of the maternal imagination during a fecundating copulation may be sufficient to impress the germ within her with the necessary impulse; and the plea has been occasionally urged in courts of justice. Of this we have an example in a well-known case, tried in New York about fifty years ago. A mulatto woman was delivered of a female bastard child, which became chargeable to the authorities of the city. When interrogated, she stated that a black man of the name of Whis- telo was the father, who was accordingly apprehended for the purpose of being assessed with the expenses. Several physicians, who were summoned before the magistrates, gave it as their opinion, that it was not his child, but the offspring of a white man. Dr. S. Mitchill, how- ever, who, according to Dr. Beck, seemed to be a believer in the in- fluence of the imagination over the foetus, thought it probable that the negro was the father. Owing to this difference of sentiment, the case was carried before the mayor, recorder, and several aldermen. It appeared in evidence, that the colour of the child was somewhat dark, but lighter than the generality of mulattoes, and that its hair was straight, and had none of the peculiarities of the negro race. The court very properly decided in favour of Whistelo, and of course against the testimony of Dr. Mitchill, who, moreover, maintained, that as alteration of complexion has occasionally been noticed in the human subject,—as of negroes turning partly white,—and in animals, this might be a parallel instance.2 The opinion does not seem, however, entitled to much greater estimation than that of the poor Irishwoman, 1 See, on all this subject, Flourens, De la Longevite Humaine et de la Quantite de Vie sur le Globe, 2de edit., p. 174, Paris, 1855. 2 Beck's Medical Jurisprudence, 6th edition, i. 500, Philad., 1838. For some ridicu- lous stories of this kind, see Demangeon, Du Pouvoir de Hmagination sur la Physique et le Moral de l'Homme, p. 201, Paris, 1834. INFLUENCE OF THE MATERNAL IMAGINATION. 471 in a London police report, who ascribed the fact of her having brought forth a thick-lipped, woolly-headed urchin to her having eaten some black potatoes during her pregnancy! It is obvious, that the effect of the maternal imagination can only be invoked—by those who believe in its agency on the future appearance of the foetus—in the case of animals in which copulation is a part of the process. Where the eggs are first extruded and then fecundated, all such influence must be out of the question; and as regards the vivipa- rous animal we have seen that experiments on artificial impregnation have shown, not only that the bitch has been fecundated by sperm in- jected into the vagina, but that the resulting young have resembled the dog, whence the sperm had been obtained.1 But the strongest case in favour of the influence of the maternal imagination is given by Sir Everard Home.2 An English mare was covered by a quagga,—Equus quaccha,—a species of wild ass from Africa, which is marked somewhat like the zebra. This happened in the year 1815, in the park of Earl Morton, in Scotland. The mare was only covered once; went eleven months, four days, and nineteen hours, and the produce was a hybrid, marked like the father. The hybrid remained with the dam for four months, when it was weaned and removed from her sight. She probably saw it again in the early part of 1816, but never afterwards. In February, 1817, she was covered by an Arabian horse, and had her first foal—a filly. In May, 1818, she was covered again by the same horse, and had a second. In June, 1819, she was covered again, but this year missed: in May, 1821, she was covered a fourth time, and had a third;—all being marked like the quagga. Haller3 remarks, that the female organs of the mare seem to be corrupted by the unequal copulation with the ass, as the young foal of a horse from a mare, which previously had a mule by an ass, has something asinine in the form of its mouth and lips; and Becher4 says, that when a mare has had a mule by an ass, and afterwards a foal by a horse, there are evidently marks, in the foal, of the mother having retained some ideas of her former paramour—the ass; whence such horses are commended on account of their tolerance and other similar qualities. It has even been affirmed, that the human female, when twice married, occasionally bears children to the second husband, which resemble the first in bodily structure and mental pow- ers.* The mode in which the influence is exerted, in this and similar cases, is unfathomable; and the fact itself, although indisputable, as- - founding. Sir Everard Home6 thinks, that it is one of the strongest proofs of the effect of the mind of the mother upon her young that has ever been recorded. Although we are totally incapable of suggesting any satisfactory solution, it appears more probable, that the impression must have been made on the genital system, and probably on the cells 1 See page 427 of this volume. * Philosoph. Transact, for 1821, p. 21; and Lectures on Comparative Anatomy, iii. 307. 3 Element. Physiol., lib. xxix. sect. ii. § 10, Bern., 1766. 4 Physic. Subterran., Lips., 1703. 6 Art. Generation, by Dr. Allen Thomson, Cyclop. Anat. and Physiol., part xiii., p. 468, for Feb., 1838. 6 Lectures, &c, iii. 308. 472 GENERATION. of nutrition of the ovaria, rather than on the mind of the animal. Yet it must be admitted, that even this explanation does not well ac- count for a case, recorded by a recent writer.1 When Dr. Hugh Smith, of England, was travelling in the country, the dogs, as is cus- tomary, ran out and barked as he passed through a village, and amongst these he observed a little ugly cur, "that was particularly eager to ingratiate himself with a setter bitch that accompanied him. While stopping to water his horse he remarked how amorous the cur continued, and how courteous the setter continued to her admirer." Provoked at the sight, he shot the cur, and carried the bitch on horse- back for several miles. "From that day, however, she lost her appe- tite ; ate little or nothing; had no inclination to go abroad with her master, or to attend to his call; but seemed to pine like a creature in love, and express sensible concern for the loss of her gallant. Part- ridge came; but Dido had no nose. Some time after, she was put to a setter of great excellence, which had, with great difficulty, been pro- cured for the purpose; yet not a puppy did Dido bring forth, which was not the picture and colour of the cur, that the Doctor had, many months before, destroyed; and in many subsequent litters, Dido never produced a whelp that was not exactly similar to the unfortunate cur already mentioned!" The whole of this subject, as well as that of hybridity, is full of interest to the physiologist, and has recently been subjected to fresh investigation. The case of the quagga is a striking one, and the more so as it occurred in animals of different species. Many cases, however, have been observed, in which mares, covered in every in&iJnce by different horses, brought forth foals, which always partook of the cha- racters of the horse by which impregnation was first effected. In several foals in the Royal stud at Hampton Court, got by the horse Actaeon, there were unequivocal marks of the horse Colonel,—the dams of these foals having been bred from by Colonel the previous year. Again; a colt, the property of the Earl of Sheffield, got by Laurel, so resembled another horse, Camel, that it was asserted at New Market, that he must have been got by Camel. It was ascertained, however, that the mother of the colt had been covered the previous year by Camel.2 In the dog, sow, and cattle, these phenomena have been often observed; and facts have been brought forward to show, that the same thing may happen in the human species; but all observation sufficiently demonstrates that if it ever occurs it must be rare. Dr. Harvey3 has given two cases in support of the view; one of them that of a woman who was twice married, and had issue by both husbands. The children of the first marriage were five in number; of the second, three. One of these three, a daughter, bears an unmistakable resemblance to her mother's first husband; and, what makes the likeness the more striking, there was the most marked difference between the two husbands in their features and general appearance. The phenomena of hybridity have been referred to before. It is 1 J. S. Skinner, The Dog and the Sportsman, p. 19, Philad., 1845. 2 McGillivray, Aberdeen Journal, Mar. 28, 1849 ; quoted by Dr. Alexander Harvey, in Monthlv Journal of Medical Science, Oct., 1849. 3 Op. cit. HYBRIDITY. 473 undoubtedly a general rule, that hybrids do not procreate. Buffon, Mr. Hunter, and others, indeed, considered the rule absolute; but it is not admitted to be a test of specific character. Dr. Morton1 has enumerated various forms of hybridity in animals and plants; and has shown, that it occurs, not only amongst different species, but amongst different genera; and that the cross breeds have been prolific in both cases. There is great probability, that if animals were so situ- ate, that the want of inclination for each other, or the natural repug- nance could be overcome, so that sexual desire should arise, cases of hybridity would be much more frequent than they are. In the year 1848, a remarkable filly—seven months old—was found in the New Forest, England, which is evidently—from the sketch of it2—a mixed breed between the horse and the deer. The mother—a pony mare— was observed to associate with some red deer stags, and at length the foal in question was seen by her side. The nose shows an approxima- tion both to the stag and the horse; the forehead is round like that of the deer; the legs are slender and distinctly double; and the hoofs pointed, and partly double; the colour is brown, light under the belly; and the tail is like that of the deer. In cases of infertile or barren hybrids, there would appear to be a radical change produced in the germ-forming organs of both sexes. Of the modifications in the female genital system we know nothing. In the male, in many cases, no spermatozoids are found in the semen. Such has been shown to be the case with the mule by Bonnet, Pre"- vost and^)umas, Hausmann and others; and the same thing has been observed in the hybrids of goldfinches and canary birds.3 In others, real spermatozoids have been seen, but they were smaller than, and shaped differently from, the natural. The sperm of procreating hybrids does not appear to have been examined. The fact, that various different species of animals are capable of producing a prolific hybrid is fatal—as Dr. Morton4 has remarked—to the notion, that hybridity is "a test of specific affiliation; and, " con- sequently,"—he adds—" the mere fact, that the several races of man- kind produce with each other a more or less fertile progeny, consti- tutes, in itself, no proof of the unity of the human species." It has been a common opinion, not confined to the vulgar only, that the mulatto is not as fertile as the white or the negro; and the proba- ble extermination of the two races has been suggested, if the whites and blacks were allowed to intermarry;5 but the assertion can scarcely be esteemed to rest on sufficient actual observation. Were it so, it might be interesting' to inquire, whether the infertility applies rather to the female than to the male. It would probably be found, that the former would be in fault. It is affirmed by an excellent and talented traveller,6 with whom the author had the pleasure of a personal ac- 1 Hybridity in animals and plants, considered in reference to the question of the unity of the human species, New Haven, 1847, from Amer. Journ. of Science and Arts, vol. iii., second series, 1847. 2 Illustrated London News, Dec. 9, 1848. 8 Art. Semen, Cyclopaedia of Anatomy and Physiology, Pt. xxxiv. p. 508, Jan., 1849. 4 Op. cit., p. 23. 6 J. C. Nott, American Journal of the Medical Sciences, July, 1843, p. 252. 6 P. E. de Strzelecki, Physical Description of New South Wales and Van Diemen's Land, p. 346, London, 1845. 474 GENERATION. quaintance in this country, that examinations among the oldest abori- gines of every country render it evident " that their longevity has not been abridged; that the rate of mortality has not increased, but that the power of continuing or procreating the species appears to- have been curtailed. On further inquiry, this curtailment of power was not found to originate with the male, so far at least as could be observed* but some startling facts, disclosed in the course of the investigation, seem to confine it to the female." Of these the most remarkable according to Count Strzelecki, is, that whenever a union takes place between an aboriginal female and a European male, " the native female is found to lose the power of conception on a renewal of intercourse with the male of her own race, retaining only that of procreating with the white man." " Hundreds of instances"—he adds—" of this extra- ordinary fact are on record in the writer's memoranda, all tending to prove, that the sterility of the female being relative only to one, and not to another male,—and recurring invariably, under the same cir- cumstances, amongst the Hurons, Seminoles, Red Indians, Yakies (Sinaloa), Mendoza Indians, Araucos, South Sea Islanders, and natives of New Zealand, New South Wales, and Van Diemen's Land,—is not accidental, but follows laws as cogent, though as mysterious, as the rest of those connected with generation." These statements are worthy of attention, but they require fresh investigations before they can be regarded as established, especially as they certainly do not apply to the negro,—repeated opportunities occurring in this country and elsewhere to show, that the impreg- nation of a coloured woman by a white man does not deprive her of the power of subsequent procreation with an individual of her own race. They have, moreover, been contradicted, as regards the aboriginal females of Australia, by Dr. T. R. H. Thompson, R. N., who affirms, as the result of personal inquiries among several different tribes, that for a native female to bear children to a native male, after having borne half-caste children to a European father, is by no means an uncommon occurrence.1 d. Conception. Conception usually takes place without the slightest consciousness on the part of the female; hence the difficulty of reckoning the pre- cise period of gestation. Certain signs, as shivering, pains about the umbilicus, &c, are said to have occasionally denoted its occurrence; but they are rare exceptions, and the indications afforded by one female are often extremely different from those presented by another. In animals, in which generation is only accomplished during a period of generative excitement, the period of conception can be determined with accuracy; for, in by far the majority of such cases, a single copu- lation fecundates,—the existence of the state of heat indicating, that the generative organs are ripe for conception. In the human female, where sexual intercourse can take place at all periods, conception is by no means as likely to follow a single intercourse; for, although she 1 Dr. Carpenter, art. Varieties of Mankind, in Cyclop, of Anat. and Physiol., iv. 1365, Lond., 1852. >~ CONCEPTION. 475 may be always susceptible of fecundation, her genital organs are rarely, perhaps, so powerfully excited as in the animal during the season of love. It is not for the physiologist to inquire into the morbid causes of sterility in either male or female; nor is it desirable to relate all the visionary notions which have prevailed regarding the circumstances that favour conception. The ovarian conditions under which it is effected have already been canvassed under Fecundation. It has been attempted to ascertain what age and season are most prolific. From a register kept by Dr. Bland, of London, it would appear, that more women bear children between the ages of twenty- six and thirty years, than at any other period. Of two thousand one hundred and two women delivered, eighty-five were from fifteen to twenty years of age; five hundred and seventy-eight from twenty-one to twenty-five; six hundred and ninety-nine from twenty-six to thirty; four hundred and seven from thirty-one to thirty-five; two hundred and ninety-one from thirty-six to forty; thirty-six from forty-one to forty-five; and six from forty-six to forty-nine. At Marseilles, accord- ing to Raymond, women conceive most readily in autumn, and espe- cially in October; next in summer; and lastly in winter and spring,— the month of March having fewest conceptions. Morand says, that July, May, June, and August have the most; and November, March, April, and October, successively, the fewest. At the Havana, accord- ing to tables published by Don Ramon de la Sagra,1 the monthly number of births, amongst the white population, during a period of five years,—from 1825 to 1829 inclusive—was in the following order:—October, September, November, December, August, July, June, April, May, January, March, and February. February, January, March, and April are, therefore, the most favourable for conception at the Havana; June, July, May, and September the least so. Dr. Burns2 asserts, that the register for ten years of an extensive parish in Glasgow, renders it probable that August and September are most favourable. M. Villerme, from an estimate founded on eight years' observations in France, comprising 7,651,437 births, makes the ratio as follows:—May, June, April, July, February, March and December, January, August, November, September, and October:—and Dr. Gou- verneur Emerson,3 who has employed himself most profitably on the Medical Statistics of Philadelphia, has furnished a table of the number of births, during each month, for the ten years ending in 1830; accord- ing to which the numbers are in the following order:—December, September, January, March, October, August, November, February, July, May, April, and June,—the greatest number of conceptions occurring, consequently, in April, January, and May,—the least in October, August, and September. The proportion will, of course, be regulated to a great extent by the time of marriage. In England,4 the greatest number of these occurs in autumn, and consequently we should expect the ratio of births to be greatest in winter, which is the fact. The following table 1 Ilistoria Economico-Politica y Estadistica de la Isla de Cuba, Habana, 1833. 2 Principles of Midwifery, 3d edit., p. 126, London, 1814. 8 Arner**Joum. of the Med. Sciences, for Nov., 1831. 4 Filth Annual Report of the Registrar-General, &c, London, 1843, 476 GENERATION. shows the relative number of marriages, births, and deaths, in the seasons of the year, corrected for inequality of time. Autumn. Spring. Summer. Winter. Marriages, . . . 36,306 31,355 29,634 25,482 Births, . . . 131,257 129,677 121,053 120,356 The human female is uniparous,—one ovum only, as a general rule, being fecundated: numerous other animals are multiparous or bring forth many at a birth. The law on this subject is not fixed, however. Occasionally, the human female brings forth twins, triplets, or quad- ruplets ; and the multiparous animal is not always delivered of the same number. It is impossible to account for those differences. The ovarists refer them to the female; the animalculists to the male; and facts have been found to support both views. Certain females, who have been frequently married, have been multiparous with each hus- band ; and analogous facts have occurred to males under similar cir- cumstances. Menage cites the case of a man, whose wife brought him twenty-one children in seven deliveries; and the same individual having impregnated his servant-maid, she brought forth triplets like- wise. It is asserted, that, in 1755, a peasant was presented to the Empress of Russia, who was seventy years of age, and had been twice married. His first wife had fifty-seven children at twenty-one births. In four deliveries she had four children at each; in seven, three; and in six, two. This appears to be the ne plus ultra of such cases! In the Hospice de la Maternite, of Paris, it has been observed, that twins occur once in about eighty cases. In the Westminster Hos- pital, the same ratio has been found to prevail. In 1840, of 547,293 births in the kingdom of Prussia, 6,381 were twin cases, or 1 in 90. In the British Lying-in Hospital, the proportion was not greater than 1 in 91; whilst in the Dublin Lying-in Hospital, the cases were nearly twice as frequent, or about 1 in 57. Dr. Collins1 remarks on the sin- gular circumstance, that in Ireland the proportional number of women giving birth to twins, is nearly a third greater than in any other country of which he had been able to obtain authentic records. Ho states the proportion in France to be one in 95 births; in Germany, one in 80 ; in England, one in 92; in Scotland, one in 95 ; and in Ireland, one in 62. According to the report of Dr. Simpson,2 in the Edinburgh Royal Maternity Hospital, of 1417 women delivered, 17, or 1 in 83, gave birth to twins. Of 129,172 women delivered in the Lying- in Hospital, Dublin, 2062 gave birth to twins; 29 produced three at a birth, which is in the proportion of one in 4450; and one only gave birth to four. In this country, the average of twin cases, according to Dr. Dewees, is about 1 in 75. Triplet cases were found to occur in the Hospice de la Maternite, of Paris, about once in 9000 times; and in the Dublin Hospital once in 5050 times; the balance, again, being largely in favour of the prolific powers of the Irish. Dr. Dewees affirms, that in more than 9000 cases, he had not met with an instance of triplets. Of 36,000 cases in the Hospice de la Maternite not one 1 A Practical Treatise on Midwifery, London, 1835 : republished in Bell's Select Library, Philad., 1838. 2 Monthly Journal and Retrospect of the Medical Sciences, Nov. 1848, p. 334. CONCEPTION. 477 brought forth four children. In 1849, a woman, a native of Ireland, living in Southwark, Philadelphia, was delivered of four children,— all boys, each weighing about five pounds:—three of them were born alive. This woman, who was about 19 years of age, is said to have had six children by a former husband at three parturitions. At the first, she was delivered of a boy and a girl; at the second of a girl, and at the third of two boys and a girl. There are cases on record where five have been born. Beyond this number the tales of authors ought perhaps to be esteemed fabulous. The statistics of the Lying- in Hospital of Vienna and of Belgium, in reference to this subject, are given hereafter.' On inspecting the following table, it will be found to be a general rule amongst quadrupeds, that the largest and most formidable bring forth the fewest young, and that the lower tribes are unusually fruit- ful,—the number produced compensating, in some measure, for their natural feebleness, which renders them constantly liable to destruction. On the other hand, were the larger species to be as prolific as the smaller, the latter would soon be blotted from existence. What would have been the condition of animated nature, if the gigantic mastodon, once the inhabitant of our plains, could have engendered as frequently and as numerously as the rabbit! For wise purposes, it has been or- dained, that the more formidable animals seldom begin the work of reproduction until they have nearly attained their full size; whilst those that bring forth many commence much earlier. Lastly, there is some correspondence between the duration of gestation and the size of the animal. Animals. Duration of Gesta- Number of Animals. Duration of Gesta- Number of tion. Young. tion. Young. Ape . . about 9 months, 1 Lioness . ... 4 or 5 Bat . . . 2 Tigress . . 4 or 5 Rat . . 5 or six weeks, 5 or 6 Cat . . 8 weeks, 4 or 5 Mouse ... 6 to 10 Seal . . ... 2 Hare . . 30 days, 4 or 5 11 months ") Rabbit . Guinea-pig Do. Do. Mare . . and some > 1 3 weeks, 5 to 12 days, J Squirrel . 6 weeks, 4 or 5 Ewe . . 5 months, lor 2 Mole . . ... 4 or 5 Goat . . 4£ months, 1, 2, or 3 Bear . . . . . 2 or 3 Cow . . 9 months, lor 2 Otter . . 9 weeks, 4 or 5 Reindeer. 8 months, 2 Bitch . . 9 weeks, 4 to 10 Hind . . Do. 1 or 2 Ferret Wolf . . 6 weeks, 10 weeks, 6 or 7 5 to 9 Sow . . 4 months, 6 to 12 \ and more J Opossum. . 4 or 5 Camel 12 months, 1 Kangaroo ... 1 Walrus . 9 months, 1 Jackall . . 6 to 8 Elephant. 2 years, 1 Fox . . 10 weeks, 4 or 5 Whale . 9 or 10 months, 1 or 2 Conception being entirely removed from all influence of volition, it is obviously impracticable, by any effort of the will, either to modify the sex of the foetus or its general physical and moral characters. Yet 1 See, on all this subject, F. H. Ramsbotham, The Principles and Practice of Obste- tric Medicine and Surgery, &c, Amer. edit, by Dr. W. V. Keating, p. 640, Philad.,1855. 478 GENERATION. idle and absurd schemes have been devised for both one and the other. The older philosophers, as Hippocrates and Aristotle, believed that the right testicle and ovary furnish the rudiments of males, and the same organs, on the left side, those of females: and some of the old writers de Re Rusticd, assert that such was the result of their experiments with the ram. These statements gave rise to a pretended " art of procreat- ing the sexes at pleasure," which has been seriously revived in our own time. Mr. John Hunter published the details of an experiment in the " Philosophical Transactions," which was instituted for the purpose of determining, whether the number of young be equally divided between the ovaries. He took two sows from the same litter, deprived one of an ovary, and counted the number of pigs produced by each during its life. The sow with two ovaries had one hundred and sixty-two: the spayed one only seventy-six. Hence he inferred, that each ovary had nearly the same proportion. In this experiment, he makes no mention of the interesting fact—the proportion of the males in the two cases, and whether they were all of the same sex in the sow that had been spayed. Had his attention been drawn to this point, the results would doubtless have been sufficient to subvert the strange hypothesis brought forward by M. Millot,1 that males are produced by the right ovary; females by the left; and the wild assertion, that he could so manage the position of the woman during copulation, that she should certainly have a boy or girl, as might have been determined upon; in confirmation of which he published the names of mothers, who had followed his advice, and succeeded to their wishes! A case, related by Dr. Granville, of London, to the Royal Society,2 has com- pletely exhibited the inaccuracy of this notion. A woman, forty years of age, died at the Hospice de la Maternite of Paris, six or seven days after delivery, of what had been supposed to be disease of the heart. The body was opened in the presence of Dr. Granville, and the disease was found to be aneurism of the aorta. On examining the uterus, it was discovered to be at least four times the size of the unimpregnated organ. It had acquired its full developement on the right side only, where it had the usual pyriform convexity; whilst the left formed a straight line scarcely half an inch distant from the centre, although it was more than two inches from the same point to the outline of the right side. The Fallopian tube and ovary, with the other parts on the right side, had the natural appearance; but they were not to be found on/ the left. Yet this woman had been the mother of eleven children of both sexes; and a few days before her death had been delivered of twins,—one male and one female.3 M. Jadelot has given the dissection of a female, who had been delivered of several children—boys and girls; yet she had no ovary or Fallopian tube on the right side. 'M. Lepelletier4 asserts, that he saw a similar case in the Hospital at Mans, in 1825; and the Recueils of the Societe de Medecine, of Paris, contain the history of an extra-uterine gestation, in which a male foetus was contained in the left ovary. 1 L'Art. de Procter les Sexes a Volonte; nouvelle e"dit., par M. Breschet, Paris, 1829. 2 Philos. Transact, for 1808, p. 308. 3 Sir E. Home, Lect. on Comp. Anat., iii. 300. * Physiologie Medicale et Philosophique, iv. 333, Paris, 1833. LEGITIMATE AND ILLEGITIMATE CONCEPTIONS. 479 Independently of these decisive cases, it has been found, that when one of the ovaries has been entirely disabled by disease, the other has conceived of both sexes. In rabbits, an ovary has been removed; yet both male and female foetuses have subsequently been engendered; and if the gravid uterus of one of those animals be examined, male and female foetuses may be found in the same cornu of the uterus, all of which, owing to peculiarity of construction of the uterus,—the cornu forming the main part of the organ,—must manifestly have proceeded from the corresponding ovary. We are totally unaware, therefore, of the circumstances that give rise to the sex of the new being; although satisfied that it is in no respect influenced by the desires of the parents. We shall see, hereafter, that some distinguished physiologists believe, that the sex is not settled at the moment of conception, and that it is determined at a later period, after the embryo has undergone a certain degree of developement. It is an ancient opinion, which seems to be in some measure con- firmed by what we notice in certain animals, that the character of the offspring is largely dependent upon the moral and physical qualities of the parent; and a M. Robert, of Paris, in a dissertation under the pompous title of Megalanthropogenesis, has fancifully maintained, that the race of men of genius may be perpetuated by uniting them to women possessed of the same faculties. Similar views are maintained by Claude Quillet.1 It is an old view, that the procreative energy of the parents has much to do with the mental and corporeal activity of the offspring. Hence it is, that bastards have been presumed to excel in this respect. Such is the view of Burton,2 and the same idea is put, by Shakspeare, into the mouth of Edmund. " Why brand they us With base ? with baseness ? bastardy ? base ? base ? Who in the lusty stealth of nature take More composition and fierce quality Than doth within a dull, stale, tired bed Go to the creating a whole tribe of fops Got 'tween sleep and wake 1"—King Leak, i. 2. Much doubtless, depends upon the condition of the parents as regards their organization and strength of constitution. The remark— " fortes creantur fortibus et bonis"—is true within certain limits; but we have no proof, that the ardour of the procreative effort can have any such influence; and the ratio of instances of bastards, who have been sig- nalized for the possession of unusual vigour—mental or corporeal—to the whole number of illegitimates, is not greater than in the case of those born in wedlock. It has been stated that the number of male children is greater in cases of legitimate than of illegitimate births. Mr. Babbage3 has compared the ratio in different countries, from which he has formed the following table:— 1 Callipaedia, sive de Pulchrae Prolis Habendse Ratione, &c, Lond., 1708. 2 Anatomy of Melancholy. 3 Brewster's Journal of Science, New Series, No. 1. 480 GENERATION. Legitimate Births. Number of Births obserred. Illegitimate Births. Number of Births observed. Females. Males. Females. Males. France, Naples, Prussia, Westphalia, Montpellier, 10,000 10,000 10,000 10,000 10,000 10,657 10,452 10,609 10,471 10,707 9,656,135 1,059,055 3,672,251 151,169 25,064 10,000 10,000 10,000 10,000 10,000 10,484 10,267 10,278 10,039 10,081 673,047 51,309 212,804 19,050 2,735 Mean, 10,000 10,575 10,000 10,250 Of 248,544 children registered in England,1 15,389 were illegiti- mate; so that 1 in 16 of the children born in England is not born in wedlock. In Austria, in the year 1843, 1 child in 4 was illegitimate; and in Vienna, 1 in 2.2 From the statistics of the Gebaranstalt, the Imperial Lying-in Hospital of Vienna, which is the great receptacle of illegitimate con- ceptions, it would seem that the number of female children born in it actually exceeds that of males. Of 21,212 children born "there in the seven years prior to 1838, the sexes were in the proportion of 10,584 males to 10,628 females.3 It is proper, however, to remark, that the Registrar-General found the reverse of this to be the fact in England.4 Of the legitimate births, the boys were to the girls as 1054 to 100*0; whilst of the illegitimate, they were as 108*0 to 100*0. "It is, I believe, assumed"—he remarks—"in the French returns, that foundling children are^ illegitimate. If it be true, as is stated by those acquainted with the matter, that many of the children sent to the found- ling hospitals in France are the offspring of married people, who pro- bably abandon a greater proportion of girls than boys, it will follow;— first, that the proportion of children born out of wedlock is nearly the same in England as in France; and, secondly, that the inference from the returns of Continental States having foundling hospitals as to the relative predominance of females among natural children is fallacious." It is obvious, that these authoritative statistical conclusions must make us pause before we can regard it as at all established, that the ratio of boys to girls is less amongst illegitimate than legitimate conceptions. To elucidate the effect of the condition of the parent on the future progeny, M. Girou de Buzareingues5 gave a violent blow to a bitch whilst lined; in consequence of which she was paraplegic for some days. She brought forth eight pups, all of which, except one, had the hind legs wanting, malformed, or weak. It has been attempted to show, also, that the corporeal vigour of the parents has much to do even with the future sex. M. Girou instituted a series of experiments on differ- 1 Fifth Annual Report of the Registrar-General of Births, Deaths, and Marriages, in England, Lond., 1843. 2 Knolz, Jahresbericht, u. s. w. in der Provinz Oesterreich unter der Enns, vom Jahre, 1843, S. xlix. Wien, 1844. 3 Austria: its Literary, Scientific, and Medical Institutions, by W. R. Wilde, p. 22, note, Dublin, 1843. 4 Fifth Annual Report, &c, Lond., 1843. 5 Memoire sur les Rapports des Sexes, &c, Paris, 1836; and a farther Memoir, in Revue Medicale, 1837. PROPORTION OF MALE TO FEMALE BIRTHS. 481 ent animals, but especially on sheep, to discover, whether a greater number of male or female lambs may not be produced at the will of the agriculturist. The plan adopted to insure this result was to employ very young rams in that division of the flock where it was desired to obtain females; and strong and vigorous rams, of four or five years of a<*e, in that from which males were to be procured. The result would seem to show, that the younger rams begat females in greater propor- tion; and the older, males. M. Girou asserts, that females commonly predominate amongst animals that live in a state of " polygamy," and it is affirmed, that the same fact has been observed, in Turkey and Persia, in the human species; but statistical data are wanting. These and other facts have seemed, however, to show, that in the act of gene- ration, it is, as a general rule, the stronger individual that regulates the sex of the progeny. M. Moreau1 has arrived at this conclusion as the result of long observation. He is of opinion, that, to a certain extent, a boy or girl may be begotten at will by strengthening or weakening the father or mother, previous to the act of generation ; and he states, that by acting on this rule he has seen, in numerous instances, his ad- vice followed by the desired results. From the researches of Hofacker2 and Sadler,3 it would appear, that, as a general rule, when the mother is older than the father, fewer boys are born than girls, and the same is observed where they are of equal age; but the greater the excess of age on the part of the father, the greater will be the ratio of boys. The fact deduced from the observa- tions of these gentlemen has been characterized by a recent writer as "one of the most remarkable contributions that have yet been made by statistics to physiology."4 The following table gives the average results obtained by them; the numbers indicating the proportion of male births to 100 females. Hofacker. Sadler. Father younger than mother, 90*6 Father younger than mother, 86'5 Father and mother of equal age, 90-0 Father and mother of equal age, 94-8 Father older by 1 to 6 years, 103-4 Father older by 1 to 6 years, 103*7 6 to 9 124-7 6 to 11 126-7 9 to 18 143-7 11 to 16 147-7 18 and more, 200-0 16 and more, 163-2 Researches by Dr. Emerson,5 have led him to the conclusion, that the extensive prevalence of every severe zymotic disease; and in- deed any occurrence, which directly or indirectly exerts a decidedly depressing effect upon a community, will be indicated in the record of births by a conspicuous reduction in the proportion of males. The ordinary average excess of male births was found, by former calcula- tions, to be, in Philadelphia, about 7 per cent.; and during the cholera months of August and September, 1832, the diminution of male con- ceptions was at the rate of more than 17 per cent.; and a similar dimi- nution occurred in Paris, and other places, during the existence of the same malady. 1 Edinb. Med. and Surg. Journ., Oct., 1844 ; from L'Expe"rience, 4 Juillet, 1844. 2 Annates d'Hygiene, p. 537, July, 1829. 3 The Law of Population, ii. 343, Lond., 1830. ' Carpenter, Human Physiology, § 771, Lond., 1842. s American Journal of the Medical Sciences, for July, 1848, p. 78. VOL. II.—31 482 GENERATION. It appears, that the general proportion of males born to females is everywhere pretty nearly the same. The calculations of Hufeland give the numbers'in Germany as 21 to 20; those of Girou, in France, as 21 to 19*69 ; and in Paris, 21 to 20*27; the census of Great Britain taken in 1821, estimates it as 21 to 20*066, and the Registrar-General of England,1 at 21 to 20*026. In the Dublin Lying-in Hospital during ten years, the ratio was 21 to 19*33; in the Eastern District of the Royal Maternity Charity, of London, during the year 1830, 21 to 19*64; and in the province of Austria, in the year 1823,8 21 to 20. In Philadelphia, according to the tables of Dr. Emerson,3 the proportion from 1821 to 1830, was 21 to 19*43. In the whole of Europe it is estimated to be 21 to 19*81. Although, however, a greater number of males may be born, they seem more exposed to natural or accidental death; for amongst adults the balance is much less in their favour; and, indeed, the number of adult females rather exceeds that of the males. Dr. Emerson4 states, that of the children born in Philadelphia during the ten years included between 1821 and 1830, amounting, according to the returns made to the Board of Health, to 64,642,— there were 2,496 more males than females. But, notwithstanding the males at birth exceeded the females about 1\ per cent., the census of 1830 shows, that by the fifth year, the male excess is reduced to about 5 per cent., and at ten years to only 1 per cent.; and that, the reduc- tion still going on, the number of females between the ages of 10 and 15 exceeds that of the males about 8 per cent.; and between 15 and 20, 7*3 per cent.: facts, which clearly authorize the deduction of M. Quetelet,5 that during the early stages of life there are agencies ope- rating to reduce the proportion of the male sex. Dr. Emerson's inves- tigations exhibit clearly, that the greater liability of males to accidenta did not furnish a sufficient reason for their greater mortality;—the deaths reported in the Philadelphia bills, under the head of casualties, constituting but a small proportion of the whole mortality; and this— when burns and scalds are included—being more considerable in the case of the female. The gross male mortality under the twentieth year, for the ten years above mentioned, exceeded the female mor- tality in the ratio of 7*94 per cent. The diseases, which seemed to be particularly obnoxious to the male sex, were, according to the Phila- delphia bills, the following—arranged in the order of their decreasing mortality:—inflammation of the brain, inflammation of the bowels, bronchitis, croup, inflammation of the lungs, fevers of all kinds (except scarlet), convulsions, general dropsy, dropsy of the head, and smallpox. To these sources of mortality may be added those under the head of casualties, and others vaguely designated debility, decay, &c. The few cases in which the deaths of females predominated were,—consumption, dropsy of the chest, scarlet fever, burns and scalds, and hooping-cough. In subsequent statistical researches on this interesting topic, Dr. Emer- 1 Fifth Annual Report of the Registrar-General of Births, Deaths, and Marriages in England, Lond., 1843. 2 Knolz, op. cit. 9 Amer. Journ. of the Med. Sciences, for Nov., 1835. « Ibid., for Nov., 1835, p. 56. » Sur l'Homme, i. 156, Paris, 1835. PROPORTION OF STILLBORN. 483 son1 found, that in Philadelphia, the diseases, which prove especially fatal to male children, are—inflammation of the brain and its conse- quences, convulsions and hydrocephalus, inflammation of the lungs, stomach, bowels, &c, and fevers of all kinds,—some of the eruptive excepted. On the other hand, the diseases in which the deaths of female children preponderate are few in number,—the chief being hooping-cough, scarlet-fever, and consumption; whence he concludes, that the maladies most fatal to male children seem to be of the sthenic class,—to females, of the asthenic. It would appear, that on the average, about one infant in twenty is still-born. The cause of this is a difficult inquiry; as well as that of the greater ratio—double—in cities than in the country; in some cities than in others; amongst male infants rather than females; in winter than in summer; and amongst the illegitimate rather than the legitimate. It is an interesting topic of investigation for the medical statistician. The following table, embracing the statistics of the Impe- rial lying-in Hospital of Vienna, which as before remarked, is the great receptacle for illegitimate conceptions, is interesting on account of the number of cases observed. It is given by Mr. Wilde,2 of Dublin, who states, that it was collected and arranged with much care from the un- published records of the hospital for the eight years ending Dec, 31, 1840, and exhibits the results of 25,906 deliveries, and 26,149 births. NUMBER OF BIRTHS, 26,149. f Single births, 25,638 Children, \ Twins, 248 times, 496, or 1 in 105-43 ( Triplets, 5 " 15, or 1 in 5229-8 Total births, 26,149 o • oo /mo v_iv / Boys, 11,717 \ Proportion of Males Sex in 23,413 births, | ^ n*696 } J1(H) Femaleg( 100.n f Boys, 48 "j Sex of still-born children J Girls, 45 I Proportion of Males to in 2201 births, — f 100 Females, 106-66 1 Total, 93 J Total still-born in 23,413 births, 939, or 1 in 24-92 Died before the ninth day in 23,222, 1482, or 1 in 15-66 Sexes in 95 of these i BoyS> 49 1 ProPortion of Males to bexes in 95 ol tnese, \GiriSf 46 ] 100 Females, 106-52 Abortions and premature deliveries ) _„. , . on 10 in 25,705, } 674, or 1 in 38-13 It will be observed, that the ratio of still-born is smaller than the average; yet it is much higher than in the whole of the Austrian dominions, in which the proportion, according to Mr. Wilde, was 1 in 30*62; and according to Knolz,3 in 1843, in the province of Austria, 1 in 36*4. It is difficult, however, to believe, that Mr. Wilde's statis- tics can be accurate, when we observe the ratio in Linz stated to be 1 in 155*35 only!4 If all the statistical observations be esteemed accu- rate, they certainly exhibit a great and inexplicable difference in countries on all these topics. The official records of Belgium,5 for ex- 1 Amer. Journ. of the Med. Sciences, for Jan., 1846, p. 92. 1 Op. cit., p. 223. 5 Op. cit. « Ibid., 225. * Statintique de la Belgique.—Population, Mouvement de 1'E.tat Civil pendant l'Anme 1844, p. vi., Bruxelles, Novemb., 1845. 484 GENERATION. ample, give the number of still-born legitimate males to that of still- born legitimate females as 1*39 to 1; whilst the ratio of still-born ille- gitimate males to females is only 1*14 to 1. The legitimate males born alive were to the females in the ratio of 1*05 to 1; the illeo-itimate of 1*04 to 1. The following was the proportion of single births, of the born alive, of the still born, and of twins to the whole number of births, including the still-born, in four successive years:— 1841. 1842. 1843. 1844. Single births, 1 in 1-02 1-02 1-02 1-02 Born alive, 1 in 1-04 1-04 1-04 1-04 Born dead, 1 in 25-97 25-67 24-09 23-76 Twins, 1 in 58-38 54-88 53-44 52-40 In 1841, there were 9 triple births (8 boys and 19 girls); in 1842 16 (25 boys and 23 girls); in 1843, 10 (11 boys and 19 girls); and in 1844, 11 (20 boys and 13 girls). In 1842, there was one quadruple birth (all females); and in 1844, there were 2 (2 males and 6 females). A recent German author, Dr. G. Thomas,1 has estimated twin cases at 1 in 80; triplets at 1 in 6 to 7000; and quadruplets at 1 in 20 to 50,000 cases. A statistical contribution to obstetrical physiology has been made by Professor J. Y. Simpson, of Edinburgh,2 which is full of interest in this relation. From elaborate tables contained in Dr. Collins's Treatise on Midwifery, he deduces the following propositions. First. That the dangers and difficulties of parturition are greater to the mother in male than in female births. Secondly. That the dangers and accidents from parturition and its results are greater to the child in male than in female births: and Thirdly. That for the very marked difference between the difficulties and perils, both to the child and the mother, in male, from that which exists in female births, there is no other traceable cause in the mechanism of parturition, than the larger size of the head of the male child. The records of the Dublin hospital showed, that there died during the process of parturition, "and probably as a consequence of the injuries to which they were subjected," 151 male children for every 100 female. There was thus an excess of 50 male deaths in every 250 children, or 20 in every 100;—referable, according to Dr. Simpson, to the greater size of the head of the male infant. " Further," he adds, " we may take it for granted, that, on a low computation, 1, in every 50 children born, dies during labour, about 1 in every 25 cases being a still birth. To be certain, however, not to overstep our limits, let us reckon only 1 in every 75 children to die during parturition, and 1 in every 5, or 20 per cent, of those that thus perish, to be formed by that excess of mortality of males over females, which we can trace to no other cause than the influence of the greater dimensions of the male head. In England and Wales about 500,000 births take place annu- ally. By the above computation, more than 6500 of the offspring of these births die during labour, and one-fifth of that number are lost in consequence of the sex and size of the male child. In Great 1 Die Physiologie des Menschen, S. 60, Leipz., 1853. 2 Edinb. Med. and Surg. Journal, Oct., 1844. SUPERFCETATION. 485 Britain, therefore, the lives of 15,000 infants are annually lost in child- birth, from the operation of this agency." Applying a similar mode of reasoning to account for the excess of male infants, who die within the first year after birth, Dr. Simpson concludes, that there perish annually in Great Britain, upwards of 5000 children within the first year after birth, whose death is referable to the influence of the sex, and greater size of the male head during labour. e. Superfcetation. It has been an oft-agitated question, whether, after an ovule has been impregnated and passed down into the cavity of the uterus, an- other ovule may not be fecundated; so that the products of two con- ceptions may undergo their respective developements in the uterus, and be delivered at an interval corresponding to that between the con- ceptions. Many physiologists have believed this to be possible, and have given it the name superfcetation. The case, cited from Sir Eve- rard Home, of a young female, who died on the seventh or eighth day after conception, exhibits that the mouth of the womb is at an early period completely obstructed by a plug of impervious mucus—mucus infranchissable of M. Pouchet, and that the inner surface of the uterus is lined by an efflorescence of plastic matter, the nature of which will be described under the next head. When such a change has been effected, it would seem to be impossible for the male sperm to reach the ovary; and accordingly, the general belief is, that superfcetation is only practicable prior to these changes, and when there is a second vesicle ripe for impregnation. Of this kind of superconception or super- fecundation it is probable, that twin and triplet cases are often, if not always, examples;—one ovule being impregnated at one copulation, and another at the next.1 This seems to be common in animals. The dog-breeders have often remarked, that a bitch, after having been lined, will readily admit a dog of a very different kind to copulate with her; and different descriptions of puppies have been brought forth,—some resembling each of the fathers. Sir Everard Home2 states, that a setter bitch was lined in the morning by a pointer. The bitch went out with the gamekeeper, who had with him a Russian setter of his own, which also lined her in the course of the afternoon. She had a litter of six puppies; two only of which were preserved. One of these bore an exact resemblance to the pointer; the other to the Russian setter,—the male influence being predominant in each. Of this kind of superfcetation or double conception we have several instances on record, of which the following are amongst the most strik- ing;—the male parent of the respective foetuses having differed in colour. The first is the well-known case cited by Buffon3 of a female at Charleston, South Carolina, who was delivered dn 1714 of twins, within a very short time of each other. One of these was black; the other white. This circumstance led to an inquiry, when the woman confessed, that on a particular day, immediately after her husband had 1 Art. Zwillinge, in Pierer's Anat. Physiol. Real. Worterb., Band viii., Altenb., 2 Lect. on Comp. Anat., iii. 302. 3 Hist. Nat. de l'Homme, Puberte. 486 GENERATION. left his bed, a negro entered her room, and compelled her to gratify his wishes, under threats of murdering her. Several cases of women in the West India Islands having had, at one birth, a black and a white child, are recorded; and Dr. Moseley1 gives the following case, which is very analogous to that described by Buffon. A negro woman brought forth two children at a birth, both of a size, one of which was a negro, the other a mulatto. On being interrogated, she said, that a white man belonging to the estate came to her hut one morning before she was up, and that she received his embraces soon after her black husband had quitted her. Sir Everard Home2 likewise asserts, that a particular friend of his " knows a black woman, who has two children now alive, that are twins and were suckled together; one quite black, the other a mulatto. The woman herself does not hesitate in stating the circumstances: one morning just after her husband had left her, a soldier, for whom she had a partiality, came into her hut, and was con- nected with her, about three or four hours after leaving the embraces of her husband." One of the author's pupils, Dr. N. J. Huston, then of Harrisonburg, Virginia, also communicated to him the case of a female who was delivered, in March, 1827, of a negro child and a mu- latto on the same night. Where negro slavery exists, such cases are sufficiently numerous:3 two have been recorded recently.4 So far, therefore, as regards the possibility of a second vesicle being fecun- dated, prior to the closure of the os uteri by the tenacious impenetrable mucus (mucus infranchissable of Pouchet), and the flocculent membranous secretion from the interior of the uterus, or by the decidua, no doubt, we think, can be entertained: but, except in cases of double uterus, it would seem to be impracticable afterwards; although cases have been adduced to show its possibility. Still, these may perhaps be explained under the supposition, that the uterine changes, above referred to, may not be as rapidly accomplished in some cases as in others; and, again, the period of gestation is not so rigidly fixed, but that children, begot- ten at the same time, or within a few days of each other, may still be born at a distance of some weeks. A case happened to the author in which nearly three weeks elapsed between the birth of twins, in whose cases the ova were probably fecundated either at the same copulation, or within a few hours of each other. It may happen, too, that although two ova may be fecundated, both embryos may not undergo equal developement. One, indeed, may be arrested at an early stage, although still retaining the vital force. In such a case, the other will generally be found larger than common. A case of the kind occurred in the practice of Professor Hall, of the University of Maryland, and many such are on record. On the 4th of October, 1835, a lady was delivered of a female foetus, 2 inches and 10 lines in length. This occurred about half-past eight in the morning; and at two o'clock on the following morning, she was delivered of a second child, which weighed 9| pounds. The foetus, whose develope- 1 A Treatise on Tropical Diseases, p. 111. 2 Op. cit. 5 See, for an enumeration of cases, Beck's Medical Jurisprudence, 6th edit., i. 222; and Dr. Allen Thomson, in Cyclop. Anat. and Physiol., part xiii. p. 469, for Feb. 1 b38. 4 Thomas B. Taylor, New Orleans Journal of Medicine, Nov. 1848 ; and R. Carter, Medical Examiner, Sept. 1849, p. 523. PREGNANCY—DECIDUA. 487 ment was arrested, was seen by the author. When first extruded, it gave no evidences of decay, and in colour and general characters resembled the foetus of an ordinary abortion.1 Still, there are many cases recorded, in which the interval between the births of the children has been from 110 to 170 days, and neither of the children was in appearance premature; so that the possibility of a second conception, when the uterus already contains an ovum some months old, can scarcely, perhaps, be denied, however improbable it may seem; and, indeed, if the facts be admitted, the deduction seems to be irresistible. f. Pregnancy. When the fecundated ovum has been laid hold of by the fimbriated extremity of the Fallopian tube, and through this channel,—perhaps by the contraction of the tubes and the ciliary motions of its lining membrane,—has reached the cavity of the uterus, it forms a union with that viscus, to obtain the nutritive fluids which may be required for its developement, and to remain there during the whole period of preg- nancy or utero-gestation;—a condition that will now require considera- tion. Immediately after a fecundating copulation, and whilst the chief changes are transpiring in the ovary, certain modifications occur in the uterus. According to some, it dilates for the reception of the ovum. Bertrandi found this to be the case in extra-uterine pregnancy, and in females whom he opened at periods so near to conception, that the ovum was still floating in the uterus. Its substance appeared at the same time redder, softer, less compact, and more vascular than usual. In the case from Sir Everard Home,2 to which allusion has been made more than once, the lining of the uterus was covered by a beau- tiful flocculent exudation about the seventh or eighth day after impreg- nation. The soft membrane, which forms in this way, is the membrana caduca seu decidua externa, first de- Fig- 440. Bcribed by Hunter; the epichorion of Chaussier; tunica exterior ovi, t. caduca, t. crassa membrana cribrosa, mem- brana ovi materna, membrana mucosa, decidua cellularis et spongiosa, of others. In a case, observed by Von Baer at a very early period, when the decidua Vas still in a pulpy state, the Decldua Uten- villi of the lining membrane of the uterus, which in the ov^an/between^he unimpreernated state are very short, were found to be ;™m>** l¥ decidua. *■ *—* \J I J. fl© UtCrillG V6SS618 remarkably elongated; and between the villi, and pass- are seen extending ing over them, was a substance not organized, but forming loops there! merely effused, and evidently the decidua at an ex- tremely early age.3 Others, as Weber4 and Sharpey,5—and the view 1 For similar cases, of which many are on record, see Dr. Samuel Jackson, formerly of Northumberland, Pa., now of Philadelphia, in American Journal of the Medical Sciences, May, 1838, p. 237, and May, 1839, p. 256; also, Dr. J. G. Porter, ibid., Aug., 1840, p. 307; Mr. Streeter, Lond. Lancet, Oct. 30, 1841; Dr. H. N. Loomis, Buffalo Medical Journal, June, 1845; and Dr. E. Horlbeck, Charleston Medical Journal and Review, Jan., 1848. * Lect. onComp. Anat., iii. 209, Lond., 1823. 8 Op. citat. ; and Wagner's Physiology, by Willis, p. 184, Lond., 1841. 4 Hildebrandt, Ilandbuch der Anatomie, iv. 486 and 515, Braunschweig, 1832. s Muller's Elements of Physiology, by Baly, note at p. 1574, Lond., 1838. 488 GENERATION. Fig. 441. has been embraced by many eminent observers,—have maintained that the decidua is composed of the mucous membrane itself, which has undergone a considerable change in its character, and in the secre- tion from its follicles. The arrangement of this membrane has given rise to much discus- sion. The opinions of most of the anatomists of the present day are in favour of one of two views. It is main- tained by some, that one of the first effects of conception is to cause the secretion of a quanti- ty of a sero-albuminous substance from the inner surface of the uterus; so that the organ becomes filled with it. At first, when the ovum arrives in it, it falls into the midst of this secretion, gradually absorbing a part for its nutrition by its outer surface. The remain- der is organized into a double membrane, one corresponding to the uterus, the other adher- ing to the ovum. This sero-albuminous sub- stance has been assimilated both to the white with which the eggs of birds become invested in passing through the oviduct; and to the Section of the Uterus about eight days after Impregna- tion. a. Cervix. 6 Fallopian tubes.' c. Decidua vera. d. Cavity of uterus. viscid substance that envelopes the mem- orifices of branous ova of certain reptiles. It is con- Fig. 442. Section of the Uterus when the Ovum is entering its Cavity. Ovum, /, surrounded by its chorion g. a. Cervix, b, b. Fallopian tubes, c. Decidua vera. d. Cavity of the uterus, e. Decidua refiexa. ceived, by some, to plug up both the orifices of the Fallopian tubes, and that of the uterus; and, according to Krum- macher1 and Dutrochet,2 it has been seen extending into the tubes; whilst the remains of that which plugged up the os uteri has been recognised in the shape of a nipple on the top of the aborted ovum. To this substance M. Breschet3 has given the name Hy- droperione. By others, it has been held, that a decidua is formed prior to the arrival of the ovum, lines the whole of the cavity and is devoid of apertures; so that when the ovum passes along the tube and attains the cornu of the uterus, it pushes the de- cidua before it;—the part so pushed forwards constituting the tunica de- cidua refiexa or ovuline, and enveloping the whole of the ovum except at the part where the decidua leaves the uterus to be reflected over it. This 1 Diss. Sistens Observationes quasd. Anatom. circa Velamenta Ovi humani, Duisb., 2 M'm. de la Societe M'dicaled'Kmulation, viii. p. i. 1817. 3 Etudes Anatomiques, Physiologiques, et Pathologkues de l'ffiuf dans l'Espece Humaine, &c, Paris, 1832. * PREGNANCY—DECIDUA REFLEXA. 489 is the seat of the future placenta. Such is the view of MM. Velpeau,1 Wao-ner,2 Kirkes and Paget3 and others. An objection to it, however, is the difficulty of so small a body pushing the decidua Fig- 443- before it; and a still strong- ? / er is the assertion of Pro- fessor Sharpey, that the structure of the decidua and of the decidua refiexa is different, a fact long since mentioned by Dr. William Hunter,4 who describes the decidua refiexa as a mem- brane of considerable thick- ness, and of a yellower co- lour than the decidua vera.5 Hence, it has been thought more probable, that the lat- ter is almost entirely a new production, the growth of which is simultaneous with the enlargement of the ovum; and that the decidua vera has no more share in its formation than by sup- plying, through its vessels, the necessary materials. At the point of supposed re- flection of the decidua re- fiexa, there is a thick stra- tum of a substance precisely similar to the decidua re- fiexa, which attaches the ovum to the side of the ute- rus, and blends intimately on the outer side of the reflex fold with the decidua vera. This is termed decidua serotina, from its appearing to have been formed at a later period. It is represented in Pig. 443. The view of Dr. Burns6 differs from this in supposing that the de- cidua consists of two layers, the innermost of which has no aperture, so that the ovum, on attaining the cornu of the uterus, pushes it for- 1 Traite Elementaire de l'Art des Accouchemens, i. 231, Paris, 1829, or Prof. Meigs's translation, 2d edit., p. 246, Philadelphia, 1838 ; also, Embryologie ou Ovologie Hu- maine, Paris, 1833. 2 Op. citat., p. 188. 3 Manual of Physiology, Amer. edit., p. 481, Philad., 1849 : see, on this subject, Baly and Kirkes, Recent Advances in the Physiology of Motion, the Senses, Generation, and Developement, p. 90, Lond., 1848. 4 Anatomical Description of the Gravid Uterus and its Contents, Lond., 1799. 6 Miiller, loc. cit. 8 Principles of Midwifery, 3d edit., p. 147, Lond., 1814. Section of the Uterus with the Ovum somewhat ad- vanced. ^ a. Muco-gelatinous substance, blocking up os uteri, b, b. Fallopian tubes, c, e. Decidua vera prolonged, at c 2, into Fallopian tube. d. Cavity of uterus, almost completely occu- pied by ovum (compare with Fig. 442). e, e. Angles at which decidua vera is reflected. /. Decidua serotina. g. Allantois. ft. Umbilical vesicle, i. Amnion, ft. Chorion, lined with outer fold of serous tunic. 490 GENERATION. wards, and it forms the decidua protrusa or decidua refiexa ; and a some- what modified view of the same kind appears to be entertained by Prof. Weber. Impregnation, according to M. Velpeau, occasions a specific excitation in the uterus, promptly followed by an exhalation of coagulable matter. This concretes, and is soon transformed into a kind of cyst or ampulla, filled with a transparent or slightly rose- coloured fluid. This species of cyst is in contact with the whole sur- face of the uterine cavity, and sometimes extends into the commence- ment of the tubes, and most frequently into the upper part of the cer- vix uteri, in the form of solid concrete cords; but is never, he says, perforated naturally, as Hunter, Bojanus, Lee, and others have main- tained. The decidua uteri, according to M. Velpeau, retains a pretty considerable thickness, especially around the placenta, until the end of gestation: the decidua refiexa, on the contrary, becomes insensibly thinner and thinner, so that at the full period it is at times of extreme tenuity. Towards the third or fourth month—a little sooner or later— they touch and press upon each other, and remain in a more or less perfect state of contiguity, until the expulsion of the secundines; but M. Velpeau asserts they are never confounded; and such appears to be the view of Bischoff.1 The decidua—the true as well as the reflected— is esteemed by M. Velpeau a simple concretion—a layer without regu- lar texture—the product of an excretion from the lining membrane of the uterus: on this account, he terms it, "anhistous membrane," (from av, privative, and loio$, "a web") or "membrane without texture." There has, indeed, been a striking dissatisfaction with the name " de- cidua." Besides the appellatives already given, M. Dutrochet has pro- posed to call it epione, M. Breschet, perione, Seiler, membrana uteri in- terna evoluta, and Burdach, nidamentum. A difficulty exists in understanding how the decidua is formed con- tinuously over the orifice of the Fallopian tubes, and the upper surface of the cervix uteri. A new production must evidently take place there. By some, however, it is not presumed to exist in the latter situation; but a plug of muco-gelatinous matter is found there, as in Fig. 443, a. The use of the decidua is, in M. Velpeau's opinion, to retain the fecundated ovum to a given point of the uterine cavity; and if his views of its arrangement were correct, the suggestion would be good. In favour of it a good deal might be said. If there were apertures in the decidua corresponding to the Fallopian tubes, it would seem, that the ovum ought more frequently to fall into the sero-albuminous mat- ter about the cervix uteri, and attachment of the placenta over the os uteri ought, perhaps, to occur more frequently than it is known to do. When placenta praevia does exist, it is owing, in the opinion of Dr. Doherty,2 to the decidua being imperfect, or to the ovum descending into the uterine cavity before that membrane has acquired sufficient consistence and tenacity to resist its weight: the consequence is, that the ovum must make i^s way to the cervix uteri and give occasion to implantation of the placenta there. Under M. Velpeau's doctrine, the attachment of the placenta ought generally to be near the cornu 1 Wagner, op. citat. p. 190 (note). 2 The Dublin Journal of Medical Science, July, 1845, p. 333. PREGNANCY—DECIDUA REFLEXA. 491 of the uterus, which is, in fact, the case. Of 34 females, who died in a state of pregnancy at the Hdpital de Perfectionnement, an examina- tion of the parts exhibited, that in twenty the centre of the placenta corresponded to the orifice of the Fallopian tube; in three, it was an- terior to it; in two, posterior; in three, beneath; and in six, near the fundus of the uterus. It is not so easy to subscribe to his assertions regarding the " anorganic" nature of the decidua. Many excellent observers have affirmed, not only that this membrane exists between the placenta and the uterus, which M. Velpeau's view, of course, ren- ders impossible, but that numerous vessels pass between it, the uterus, and the placenta. We knqw, too, that the safest and most effectual mode of inducing premature labour is to detach the decidua from the cervix uteri,' or, in other words, to break up the vessels £hat form the medium of communication between it and the lining membrane of {be uterus. It may be said, indeed, that the mere separation of the " an- organic pellicle"—as M. Velpeau designates it—is a source of irrita- tion, and may excite the uterus to the expulsion of its contents, and this is possible; but he affirms, that no tissue attaches the decidua to the uterus; and that it adheres to the inner surface of the organ merely in the manner of an excreted membraniform shell (plaque). The views of MM. Lepelletier1 and M. RaspaiF coincide with those of M. Velpeau as to the decidua being an excretion; but those of M. Baspail are modified by his peculiar opinions. He maintains, that the sur- faces of an organ—whether external or internal—having once fulfilled their appropriate functions, become detached and give place to the layer beneath them ; and we have before remarked, that he considers the secretions of the mucous and serous membranes to be constituted of the detritus of those membranes. Now, that which happens to the intestinal canal and bladder must likewise happen, he affirms, to the uterus; and as, at the period of gestation, it surpasses in develope- ment, elaboration, and vitality, every other living organ, it ought ne- cessarily to cast off its layers, in proportion as they have executed the work of elaboration. These deciduous layers constitute the decidua, on which, he says, traces of« a former adhesion to the parietes of the uterus, and of the three apertures into the organ, may be met with. But the very existence of a decidua refiexa has been denied. It is bo by Jdrg,3 Samuel,4 and by Dr. Granville, who affirms, that it is now scarcely admitted by one in ten of the anatomists of the European continent. He refers to a specimen of an impregnated uterus in the Museum of the Royal College of Surgeons of London,-which has dis- tinctly a round ovum, suspended naturally within the decidua, as a globe may be supposed to hang from some point of the interior of an oblong sac; and to two specimens, in the collection of Sir Charles Clarke, exhibiting an ovum, which had already penetrated about an inch into the cavity of the uterine decidua; but neither in these, nor in the specimen at the Royal College, is any part of the uterine decidua 1 Physiologie Medicale et Philosopbique, iv. 339, Paris, 1833. 1 Chimie Organique, p. 270, Paris, 1833. 8 Das (u-barorgan des Menschen, u. s. w., Leipz., 1808. 4 De Ovoruin Mammal. Velament. Wirceb., 1816; and art. Ei, in Encyclop. Worterb. der Med. Wissenscb., x. 107, Berlin, 1834. 492 GENERATION. pushed forward. The ovum appears to have its natural covering; and in the College specimen, there is a large space between it and the deciduous lining of the uterus. Dr. Granville regards the decidua refiexa as the external membrane of the ovum, to which Professor Boer, of Konigsberg, gave the name " cortical membrane," and which he terms cortex ovi.1 It has received various names. By Albinus, it was termed involucrum membranaceum ; by Hoboken, membrana reti- formis chorii; by Roederer, membrana filamentosa; by Blumenbach, membrana adventitia; and by Osiander, membrana crassa. To this mem- brane—and to the decidua uteri, as connected with the placenta—we shall have to refer hereafter. The decidua manifestly does not belong to the ovum; for it not only exists prior !o the descent of the ovum into the uterus, but is even formed, according to M. Breschet,2 in all cases of extra-uterine preg- nancy. (See Fig. 444.) Chaussier saw it in several cases of tubal gestation. It was present in a case of abdominal pregnancy, cited by Lallemant; and, according to M. Adelon,3 Evrat affirms, that one is secreted after every time of sexual intercourse,—which is apocryphal! It would appear, however, to be formed at each menstrual period, and, according to M. Pouchet,4 is thrown off from the tenth to the fifteenth day afterwards. He is of opinion, that the decidua is produced simply Fig. 444. Extra-Uterine Pregnancy. a. Uterus, its cavities laid open. 6. Its parietes thickened, as in natural pregnancy, c. A portion of decidua separated from its inner surface, d. Bristles to show the direction of the Fallopian tubes, e. Right Fallopian tube distended into a sac which has burst, containing the extra-uterine ovum. /. Foetus, g. Chorion, h. Ovaries ; in the right one is a well-marked corpus luteum, i. by the irritation, which succeeds to menstruation, and that it is nothing more than a pseudo-membrane "secreted between the surface of the 1 Graphic Illustrations of Abortion, &c, p. v., Lond., 1834. 2 Repert. General d'Anatomie, p. 165, pour 1828. 3 Physiologie de l'Homme, 2de edit., iv. 110, Paris, 1829. * Thcorie Positive de l'Ovulation Spontan 'e, p. 254 and p. 463, Paris, 1847. PREGNANCY—DECIDUA. 493 Fig. 445. mucous membrane and the epithelium," and taking the latter with it, is afterwards discharged ;—an arrangement which is not very intelligi- ble. Dr. Robert Lee1 affirms, that it is not formed within the uterus in all cases of extra-uterine gestation; and in ten cases detailed by him, and in one cited from M. Chaussier, it was seen distinctly surrounding the ovum in the Fallopian tube.[?] The views of Professor Goodsir' on the morphology of the decidua merit great attention. By the observations of Weber and Sharpey, it had been shown, that it is not a structure of new formation; but that when impregnation has taken place, the mucous membrane of the ute- rus swells and becomes lax, its tubular follicles—glandules utriculares— increase in size, secrete a granular matter, and are lined with epithe- lium; and its capillaries enlarge proportionally. M. Coste3 restricts the uterine changes to these. "The only modifications"—he remarks— " of which the uterus becomes the seat consist in the turgescence or erethism of its tissue, and more especially in a considerable thicken- ing of the mucous membrane;—a thickening which results especially from congestion of the bloodvessels, and an extreme developement of the glands, that enter into its composition, and, in certain subjects, plait them into more or less numerous convolutions." " In the normal state"—he affirms—"neither the opening of the cervix uteri nor that of the Fallopian tubes is closed by mem- brane." They are always free, perme- able, and consequently permit the ovum to pass into the cavity of the uterus, and the folds of the mucous membrane, by coming in contact, are sufficient to arrest it. Mr. Goodsir has remarked, however, that the interfollicular spaces, in which the network of capillaries lies, are occupied by a texture consisting entirely of nucleated particles; "this is a tissue represented by Baer and Wagner, and de- scribed by them as Surrounding what they twelve diameters. At* 1, the lining of 1 , i ■ •■m / n .i epithelium is seen within the orifices; at supposed to be uterine papillae (really the 2 it has escaped. enlarged follicles), and considered by them as decidua." The increased thickness of the mucous membrane appears as much due to the developement of this interfollicular substance, as to the enlargement of the follicles. About the time at which the ovum reaches the uterus, the developed mucous membrane or decidua begins to secrete; the os uteri becomes plugged up by the secretion, which there assumes the form of elongated epithelial cells; the cavity of the uterus becomes filled with a fluid secretion, the hydroperione of M. Breschet; and in the immediate neighbourhood of the ovum, it con- sists of cells of a spherical form. Thus, the decidua, according to him, consists of two distinct elements;—the mucous membrane of the uterus Two thin segments of Human De- cidua, after recent impregnation, viewed on a dark ground; they show the openings on the surface of the membrane. magnified 6 diameters and 1 Lond. Med. Gazette, June 5, 1840. 2 Anatomical and Pathological Observations, Edinb., 1845. 3 Histoire Generale et Particuliere du Developpement des Corps Organises, p. Paris, 1S47. 220, 494 GENERATION. thickened—as remarked by Dr. Sharpey, and confirmed by Bischoff,1 Courtz,2 and others—by a peculiar developement, and by non-vascular Fig. 446. Section of the lining membrane of a human uterus at the period of commencing pregnancy showing the arrangement and other peculiarities of the glands d, d, d, with their orifices, a, a, a, on the internal sur- face of the organ. Twice the natural size. cellular substance, the product of the uterine follicles; the former con- stitutes, at a later period, the greater part of the decidua vera; the latter the decidua refiexa. This view of the constitution of the decidua —in Mr. Goodsir's opinion—clears up the doubts which were enter- tained regarding the arrangement of these membranes at the os uteri and the entrances of the Fallopian tubes. The orifices will be opened or closed, according as the cellular secretion is more or less plentiful "or in a state of more or less vigorous developement." It removes also —he conceives—the difficulty of explaining how the decidua covers the ovum—a difficulty, which cannot be reconciled with the views of Dr. Sharpey, who supposes a deposition of lymph—the old view of the constitution of the decidua. When the ovum enters the cavity of the uterus, the cellular decidua surrounds it, and becomes the decidua re- fiexa by a continuance of the same action by which it had been increas- ing in quantity prior to the arrival of the ovum. The cellular decidua grows around the ovum, by the formation of new cells, the product of those in whose vicinity the ovum happens to be situate. At this stage of its growth, the ovum with its external membrane, the chorion, which is covered by the tufts whose structure and functions are described elsewhere, is embedded in a substance that consists wholly of active nucleated cells. The absorbing cells of the tufts are constantly taking up either the matter resulting from the solution of the cells of the cel- lular decidua, or the fluid contained in those cells,—in either case from matter supplied by the vessels of the uterus, but selected and prepared by the cells of its lining membrane, now become the decidua.3 Mr. Goodsir's view harmonizes more than any of those mentioned with the mode in which new structures would seem to be formed else- where. M. Coste4 has, however, thrown the greatest light on this sub- ject. When the ovum enters the uterus, it becomes partially imbedded in the substance of the decidua, which is, as yet, quite soft; and expe- riences an increase of nutrition at the part with which the ovum comes in contact; growing up around it until it has completely enveloped the 1 Muller's Archiv., H. ii., 1846, p. 111. 2 Archives d'Anat. general et de Physiol., Sept., 1846; cited by Dr. Kirkes in Ran- king's Abstract, vol. iv. 3 British and Foreign Med. Rev., Oct., 1845, p. 303. * Comptes Rendus, Mai 24, 1847. PREGNANCY—UTERINE CHANGES. 495 ovum; and in this way the decidua refiexa is, in reality, a part of the de- cidua uteri. As the ovum becomes developed, the cavity between the Fig. 447. Fig. 448. First stage of the formation of the Decidua More advanced stage of Decidua refiexa. refiexa around the Ovum. decidua vera and the outer surface of the decidua refiexa gradually diminishes, and by the end of the third month the two portions come in contact, and are thereafter scarcely or not at all distinguishable.1 In the summer of 1854, the author had the advantage of examining the preparations of M. Coste, and of being favoured with his explana- tion of them. They certainly established the view taught by that distin- guished embryologist of the mode of formation of the decidua refiexa. When the ovum attains the interior of the uterus, which it probably does within the first ten or twelve days after conception, it forms, in a short space of time, a connexion with the uterus by means of the pla- centa, in the mode to be mentioned hereafter. During the develope- ment of the embryo, it is requisite that the uterus should be corre- spondency enlarged, in order to afford room for it, as well as to supply it with its proper nutriment. These changes in the uterine system will engage us exclusively at present. In the first two months, the augmen- tation in size is not great, and chiefly occurs in the pelvis; but, in the fourth, the increase is more rapid. The uterus is too large to be con- tained in the pelvis, and consequently rises into the hypogastrium. During the next four months, it increases in every direction, occupy- ing a larger and larger space in the cavity of the abdomen, and crowd- ing the viscera into the flanks and the iliac regions. At the termina- tion of the eighth month, it almost fills the hypogastric and umbilical regions; and its fundus approaches the epigastric region. After this, the fundus is depressed and approaches the umbilicus, leaving a flatness above, which has given rise to the old French proverb;—En ventre plat enfant il y a. During the first five mouths of utero-gestation, the womb experiences but little change, maintaining a conoidal shape. After this, however, the neck diminishes in length, and is ultimately almost entirely effaced. The organ has now a decidedly ovoid shape; and its 1 See Beraud, Manuel de Physiologie de l'Homme, &c, revu par M. Ch. Robin, p. 449, Paris, 1853. 496 GENERATION. bulk, according to Haller and Levret, is eleven and a half times greater than in the unimpregnated state. Its length, at the full period, has been estimated at about a foot; its transverse diameter at nine inches* its circumference on a level with the Fallopian tubes, at twenty-six inches; and, at the uterine portion of the cervix uteri, thirteen inches. Its weight, which, prior to impregnation, was from fourteen to eighteen drachms, is, at this time, from a pound and a half to two pounds. Whilst-the uterus is undergoing expansion, the size and situation of the parts attached to it also experience modification. The broad liga- ments are unfolded; the ovaries and Fallopian tubes are raised a little but are subsequently applied against the sides of the uterus. The vagina is elongated. The round ligaments yield to the elevation of the organ as far as their length will permit; but, ultimately, they draw the uterus forward, so that the great vessels of the abdomen are not injuriously compressed. The parietes of the abdomen are so much distended that the cuticle yields; hence, an appearance of cicatrices always exists on the abdomen of one who has borne children; and occasionally, the fasciculi of the abdominal muscles separate so as to give rise to ventral hernia. The changes, produced in the uterus, are not limited to simple dila- tation of its tissue. Its condition experiences various alterations, dependent upon the new mode of nutrition it has assumed. The whole organ undergoes not only extension but inspissation of its parietes. In its unimpregnated state, it is about four lines thick; in the third month of utero-gestation, five. Its arteries, as well as veins, enlarge, and the latter form large dilatations at the inner surface. These have been called uterine sinuses. Its lymphatics are greatly increased in size; and its proper tissue, from being hard, whitish, and incontractile, becomes red, soft, spongy, and capable of energetic contraction. It has been the general opinion, that the nerves exhibit a corresponding increase during the gravid state, but the dissections of Mr. Beck,1 which have received favour from Dr. Sharpey,2 prove, that they do not alter in their thickness, " at least, that no alteration occurs before they enter the tissue of the uterus." The representations of the gravid uterus, and of the unimpregnated uterus of one who had borne child- ren, which are given in Mr. Beck's communication, show the nervous fibrils to be the same in both cases; and no difference was observed on the dissection of a virgin uterus between its nerves and those refer- red to. M. Jobert,3 too, observed no difference in the nerves in i) impregnated and the unimpregnated state; and M. Rendu4 considers, that the knots observable in the course of the nerves during preg- nancy are not formed of nervous substance, but of the fibro-cellular tissue that sustains and protects them. A difference of sentiment has existed with regard to the nature of the new tissue of the uterus; some comparing it to the middle coat of 1 Philosophical Transactions, Part 2 for 1846. 2 Quain's Human Anatomy, by Quain and Sharpey, Amer. edit., by Leidy, ii. 356, Philad., 1849. 3 Comptes Rendus, Paris, 1841. 4 These de Paris, 1842; cited by Ollivier, Art. Ut'rus (Anatomie) in Diet, de Mede- cine, xxx. 194, Paris, 1846. PREGNANCY—STATE OF UTERUS. 497 arteries; others describing it as partly areolar and partly muscular; but an immense majority esteeming it muscular. The respectable name of Blumenbach1 is in the minority. The facts in favour of its muscularity are, indeed, overwhelming. It is clearly muscular in the mammiferous animal. Thus, in the rabbit, its muscularity, according to Dr. Blundell,2 is far more conspicuous than that of the intestines; the fibres can be seen coarse and large, and their motion may be ob- served, if they be examined immediately after the rabbit is killed. The same acute physiologist remarks, that, when developed by preg- nancy, its muscularity is so clear, that if you take a portion of it, and show it to any anatomist, asking him what its nature is, he will un- hesitatingly reply—it is muscular. This experiment, he says, he once made himself. He took a piece of the impregnated uterus, showed it to Mr. Green and Air. Key—" excellent judges on this point,"—and, without mentioning the womb, asked them to tell him what was the structure; when they immediately declared it muscular.' A similar experiment had previously been tried upon Mr. Else, who had made up his mind as to the non-muscularity of the organ. A small portion was taken to him for his opinion of its precise nature. It was from the uterus at an advanced period of utero-gestation. After carefully examining it, he gave for answer, that in his opinion it was muscular; but as it was detached from its natural locality, he could not say to what part of the body it belonged. When told, however, that it was a piece of the uterus, he examined it again, and then said that it could not be muscle, for there were no muscular fibres in the uterus.3 The arrangement of the fibres is not clearly demonstrated. Generally, per- haps, they are described as running externally, in a longitudinal direction, from the fundus to the neck: beneath this plane is another with circular fibres; but within this the fibres are interlaced in inex- tricable confusion. Some anatomists, however, enumerate as many as seven superposed planes. The fibres are of much lighter colour than those of ordinary muscles; resemble more those of the bladder and intestines, and are collected in very flat and loose fasciculi. Under the microscope, they are manifestly of the nonstriated kind; but, towards the end of utero-gestation, fibres, of a faintly striated charac- ter, resembling those of the heart—it is affirmed—have been seen. The developement of this structure would not seem to be limited to the pregnant condition. It appears to occur whenever the uterus is increased in size, as has been remarked by Dr. Horner4 and by Lob- stein.5 The muscular layers are thickest at the fundus uteri. At the cervix, they are extremely small and indistinct. After the ovum has attained the interior of the uterus, and entered the flocculent decidua, it becomes connected, in process of time, with the uterus, by means of a body to be described hereafter, called pla- centa, which is attached to the uterus, and communicates with the 1 Instit. Physiol., § 547. ! Principles and Practice of Obstetricy, Amer. edit., p. 67, Washington, 1834. • D. Davis, Principles and Practice of Obstetric Medicine, ii. 85U, Lond., 1836. 4 Lessons in Practical Anatomy, p. 304, Philad., 1836. 6 Fragment d'Anatomie Physiologique sur I'Organisation de la Matrice dans l'Espece Humaine, Paris, 1803. vol. ii.—32 498 GENERATION. foetus by a vascular cord that enters its umbilicus. The seat of the attachment of the placenta to the uterus—we have seen—is not always the same. Frequently, it is near one of the cornua; but occasionally it is implanted over the os uteri. The diversity of position has given occasion to difference of sentiment regarding the causes that influence it. By some, it has been presumed, that, in whatever part of the uterus the ovum lodges when it quits the Fallopian tube, there an adhesion is formed. By others, it has been said, that as the ovum pushes the decidua over the mouth of the Fallopian tube before it, the attachment of the placenta must be near the orifice of the tube. Such would appear to be the fact in the majority of cases, but we see so many irregularities in this respect, as to preclude us from assigning any very satisfactory reason for it. g. Signs of Pregnancy. Along with the changes that supervene in the generative apparatus during pregnancy, the whole system commonly sympathizes more or less in the altered condition. Some females, however, pass through the whole course of gestation with but slight or no disturbance of the ordinary functions; whilst with others, it is a period of incessant suf- fering. One of the earliest and most common signs is suppression of the catamenial discharge; but, of itself, this cannot be relied on, as it may result from disease. Soon after impregnation, the digestive and cerebral functions exhibit more or less modification. The female is affected with nausea and vomiting, especially in the morning after rising; the appetite is most fastidious—substances, that previously ex- cited loathing being at times desired or longed for with the greatest avidity; whilst, on the contrary, cherished articles of diet cannot be regarded without disgust. The sleep is apt to be disturbed; the tem- per unusually irritable, even in those possessed of signal equanimity on other occasions. The mammae enlarge, and become knotty, and sometimes lancinating pains are felt in them; and a secretion of a whitish serum can often be pressed out. The areola round the nipple becomes of a darker colour in the first pregnancy than it is in the vir- gin state; and it is darker during each successive pregnancy than when the female is not pregnant. There is, also, a puffy turgescence, not alone of the nipple, but of the whole of the surrounding disk, with a developement of the small follicles around the nipple. These appear- ances constitute one of the best single proofs of the existence of preg- nancy; but it is obvious, that for accurate discrimination it is necessary to be aware of the hue in each particular case in the unfecundated state; and, moreover, instances are on record of a well-marked areola occur- ring in persons who are not pregnant, as well as of an entire absence of areola in those who are. Dr. Guy remarks, that Dr. J. Beid showed him a case of enlarged mammas, with distinct areolas and mucous folli- cles, in a female who had never been, and was not at the time, preg- nant.1 Dr. Simpson2 presented before the Edinburgh Obstetrical Society a woman, seven months gone with child, whose breasts gave 1 Lond. Lancet, Dec. 22, 1838. 2 Monthly Journal of Medical Science, July, 1848, p. 244. SIGNS OF PREGNANCY. 499 no indication whatever of her pregnant state. There was no appear- ance on either of enlarged follicles, and the areola was scarcely darker than the surrounding skin; yet that she was pregnant was shown by the fact, that the pulsations of the fcetal' heart were distinctly heard. Dr. Simpson contrasted this case with that of a lady, who had never been pregnant, but who was suffering from great uterine irritation. In her, the areola was turgid, and of a dark brown colour; and the papillae were numerous and much enlarged. The author has had numerous opportunities for appreciating the in- sufficiency of these evidences taken singly. It has been affirmed by Dr. Kluge, of Berlin, M. Jacquemin, of Paris, and Dr. D'Outrepont,1 that a bluish tint of the vagina, extending from the os externum to the os uteri, is a sure test of pregnancy. Accord- ing to Kluge, this discoloration commences in the fourth week of utero-gestation, increases until the time of delivery, and ceases with the lochia. M. Jacquemin, on examining the genitals of prostitutes, in compliance with the police regulations of Paris, observed the same peculiarity of colour in the same situation in those that were pregnant: he describes it as a violet or lees of wine colour, and so distinct as never to deceive him, being sufficient of itself, and independently of other signs of pregnancy, to determine the existence of that state. M. Parent-Duchatelet2 affirms that he was present when M. Jacquemin's accuracy in this matter was successfully put to the test: in the inves- tigation, he examined no less than 4500 prostitutes. Dr. D'Outrepont has not only met with this appearance uniformly in the human subject, but in different animals, examined in every period of pregnancy, and which he destroyed, to ascertain the existence or non-existence of gestation; and similar testimony has been given by Dr. Albert.3 Dr. Montgomery," however,—from limited observation it is true,—found, that whilst in some cases the bluish colour was very obvious, in others it was so slight as to be scarcely, or not at all, perceptible. There is nothing more probable, than that the capillary circulation of the mucous coat of the vagina may be modified along with that of the interior of the uterus during pregnancy, so as to give occasion to the change of colour mentioned by those eminent observers; but it may be doubted whether the test can often be available, especially in private practice. It is the general opinion, that the blood of pregnancy always pre- sents the buffy coat and other characters of inflammation; and this has even been reckoned as one of the rational signs of pregnancy. Dr. Montgomery5 ascribes the very general belief in this, as an established fact, to the circumstance, that pregnant women are seldom bled except when labouring under some form of inflammatory disease; and he affirms, that he has often found the blood of the pregnant female with- 1 Zeitschrift fiir Geburtsk., xiv. 3; cited in Philad. Medical Examiner, Feb. 24,1844, p. 46. 2 De la Prostitution dans la Ville de Paris, i. 217, 218, Paris, 1837. 8 Zeitschrift fiir Geburtskunde, xxiii. 449, cited in British and Foreign Medico-Chi- rurgical Review, July, 1848, p. 267. 4 Op. citat., p. vi., Lond., 1837. 6 Art. Pregnancy and Delivery, Signs of, in Cyclop, of Prac. Med., Amer. edit., by the author, iii. 679, Philad., 1845. 500 GENERATION. out these characters. Hematological researches, however, show that the blood in pregnancy is materially altered. Simon1 found that of a woman in the fifth month with a slight buffy coat, but in other respects it did not differ physically from normal blood; and MM. Becquerel and Bodier2 analyzed that of nine pregnant women,—one at the fourth month, five at the fifth month, one at five months and a half, one at six months, and one at seven months. From these they con- cluded, that although pregnancy, when not far advanced, and when it has not yet exerted any sensible influence on the constitution, may not occasion any obvious alteration of the blood, it becomes sensibly changed as pregnancy advances;—the main modifications being,—that the density both of the defibrinated blood and the serum is diminished; the water, fibrin, and phosphuretted fat are increased; whilst the cor- puscles and albumen are diminished. For these and other reasons, it has been maintained by M. Cazeaux3 that the cause of many of the functional derangements in pregnancy, which are attributed to polyse- mia or plethora, is really owing to hydraemia or a condition of the blood like that of chlorosis. Some years ago,4 it was affirmed, that a German physician, Dr. Pal- lender, during a practice of eighteen years, had observed a peculiar smell of the vaginal mucus to be a constant and unerring sign of preg- nancy. The smell is musty, something resembling that of sperm or of liquor amnii; and after a vaginal examination, he says, cannot be mistaken for any other odour. In a great many cases of pregnancy, in the first, second, and third months, when the condition of the patient was doubtful owing to the early period, he never, in a single instance, failed to discover the true state of the case by means of this sign. According to his latest observations, the odour is perceptible as early as the eighth day of utero-gestation. The author knows nothing of this sign. Attention has been paid to the condition of the urine during utero- gestation ; but although a difference has appeared to exist between it and that of an unimpregnated female, it has not generally been es- teemed distinctive. M. Donne,5 indeed, affirms, that in pregnancy it contains less uric acid and phosphate of lime than in the natural state, —a difference explicable if we consider the elements that are necessary for the formation of the organs of the foetus. The crystallization of the salts of the urine is so remarkably modified, that by simple inspec- tion, without examining the female, he recognized in more than thirty cases the state of pregnancy at different periods. The observations of M. Donne in regard to the diminution in the quantity of earthy phos- phates in the urine are confirmed by Lehmann and Lubansky. It is a curious circumstance, connected with this matter, that Bokitansky6 noticed a deposition of bony matter—osteophyte—on the inner surface 1 Animal Chemistry, Syd. Soc. edit., p. 335, Lond., 1845. 2 Gazette Medicale de Paris, Nov. 23 and 30; and Dec. 7, 14, and 21, 1844. s Archives Generates de Medecine, Mars, 1850, p. 356. 4 Northern Journ. of Med., Nov., 1845 ; cited from Med. Corresp. Rhein und Westfal Aerzte, 1845, Bd. iv. H. i. 5 Gazette Medicale de Paris, 29 Mai, 1841. 6 Pathologische Anatomie, ii. 237 ; or Sydenham Society's edit, of the English trans- lation, iii. 208, Lond., 1850; or Amer. edit., Philad., 1855. SIGNS OF PREGNANCY—STATE OF THE URINE. 501 of the parietes of the skull of pregnant women, who had died suddenly after the third month of utero-gestation; as well of those who had died of different diseases, sooner or later after delivery; this he had wit- nessed so frequently, that he considered there was a connexion between the deposition and the pregnant state. It does not appear, however, that the phenomenon has been observed in other countries. According to Bokitansky, the bony layer is generally deposited on the inner sur- face of the frontal and parietal bones; but, at times, it spreads over the whole of the inner surface of the cranium; and islets (insula}) of it are observed on the base of the cranium. The urine of the pregnant female has been found to contain a pecu- liar substance, which separates and forms a pellicle on the surface. To observe this, it must be allowed-to stand from two to six days, when minute opaque bodies are observed to rise to the surface, where they gradually agglomerate and form a continuous layer which is so con- sistent that it may be almost lifted off by raising it by one of its edges. To this pellicle the name kiestein or more properly kyestein (from xvuv, " to be pregnant," and tadr^, "a pellicle,") has been given. It is whitish; opalescent; slightly granular, and may be compared to the fatty sub- stance that swims on the surface of soups, after they have been allowed to cool. When examined by the microscope, it has the aspect of an amorphous mass, consisting of minute opaque corpuscles intermingled with crystals of ammoniaco-magnesian phosphate. The kyestein re- mains on the surface for several days; the urine then becomes turbid, and small opaque masses are detached from the kyestein and fall to the bottom of the fluid; the pellicle then soon becomes destroyed. The author has distinctly noticed in some of the cases the cheesy odour of kyesteinic urine described by Dr. Bird. M. Simon1 found the whole field of vision bestrewed with numerous vibriones in active motion, and crystals of ammoniaco-magnesian phosphate. M. Zimmerman,3 too, states, that kyestein consists almost entirely of vibriones. These animalcules, he says, are first formed in the lower strata of the urine, which they render turbid. They then rise, in quantities, to the sur- face, where they form, with crystals of ammonio-phosphate of mag- nesia, amorphous phosphate of lime and urate of ammonia, the yellowish white pellicle—the kyestein. Various experiments have been made on this matter, and its value as an index of the pregnant condition, by MM. Nauche,3 Eguisier,4 Dr. Golding Bird,5 Mr. Letheby,6 Dr. Stark,7 the author's friend Dr. E. K. Kane,8 of the United States Navy; and, at the author's request, by Drs. McPheeters and Perry,9 at the time resident physicians at the 1 Animal Chemistry, Sydenham Society edition, ii. 331, Lond., 1846, or Amer. edit., Philad., 1846. 2 Cited from Casper's Wochenschrift, May 30 and June 6, 1846, in Lond. Med. Gaz., Sept., 1846. 3 La Lancette Francaise, and Lond. Lancet, No. clxvii. p. 675. 4 La Lancette Francaise, Fevrier 21, 1839 ; also, L'Experience, Juillet 25, 1839. 8 Guy's Hospital Reports, April, 1840 ; and Urinary Deposits, 2d Amer. edit., p. 287, Philad., 1851. 6 London Medical Gazette, Dec. 24, 1841. 7 Kdinb. Med. and Surg. Journal, Jan., 1842. 8 American Journal of the Med. Sciences, p. 37, July, 1842. 8 Amer. Med. Intel., March 15, 1841, p. 369. 502 GENERATION. Philadelphia Hospital, and by M. Kleybolte.1 They show, that when taken in conjunction with other phenomena, the appearance of kyestein is certainly a valuable aid in the diagnosis of pregnancy. Mr. Letheby found unquestionable evidence of it in 48 out of 50 cases between the 2d and 9th months, and was unable to account for its absence in the two exceptional cases. The result of Dr. Kane's observations, which the author had an opportunity of examining from time to time, and for the accuracy of which he can vouch, was deduced by Dr. Kane as fol- lows. First. Kyestein is not peculiar to pregnancy, but may occur whenever the lacteal elements are secreted without a free discharge from the mammae. Secondly. Although it is sometimes obscurely de- veloped and occasionally simulated by other pellicles, it is generally distinguishable from all others. Thirdly. Where pregnancy is possi- ble, the exhibition of a clearly defined kyesteinic pellicle is one of the least equivocal proofs of that condition ; and Fourthly. When the pel- licle is not found in the more advanced stages of supposed pregnancy, the probabilities, if the female be otherwise healthy, are as 20 to 1 (81 to 4) that the prognosis is incorrect. M. Simon,2 who has made many observations on the subject, goes farther than Dr. Kane. " From the observations of Kane and myself," he remarks, " it seems to follow, that pregnancy may exist without the occurrence of kyestein in the urine. If, however, there is a probability or possibility of pregnancy, and kyestein is found, then the probability is reduced almost to a cer- tainty." By means of ether, Dr. Lehmann3 succeeded in extracting from kye- stein no inconsiderable quantity of a semi-solid fat, which, when saponi- fied by potassa, and decomposed by sulphuric acid, emitted a decided odour of butyric acid. The residue of the film, which was insoluble in ether, showed, on examination, that it was a protein compound dif- fering in its properties from albumen. Dr. Lehmann concludes, that kyestein is no new peculiar substance; and that it is nothing more than a mixture of butyraceous fat, phosphate of magnesia, and a protein compound resembling casein. Along with the signs already mentioned, the uterus gradually en- larges ; and, about the end of the eighteenth week, sooner or later, quickening, as it is usually but erroneously termed, takes place, or the motion of the child is first felt. Prior to this,—from the moment, indeed, of a fecundating copulation,—the female is quick with child, but it is not until then, that the foetus has undergone the developement necessary for its movements to be perceptible. This occurrence esta- blishes the fact of pregnancy, whatever doubts may have previously existed. Where there is much corpulence, or where the fluid surround- ing the foetus is in such quantity as to throw obscurity around the case, it may be necessary, for the purpose of verifying the existence of preg- nancy, to institute an examination per vaginam. This can rarely afford 1 Casper's Wochenschrift, Jan. 11, 18, 1845, cited by Dr. Charles West, in Brit, and For. Med. Rev., Oct., 1845, p. 525. 2 Op. cit. 3 Lehrbuch der Physiologischen Chemie, 2ter Band., S. 420, Leipz., 1850; or Amer. edit, of Dr. Day's Translation, by Dr. Robt. E. Rogers, ii. 136, Philad., 1855; and Handbuch der Physiologischen Chemie, S. 193, Leipz., 1854: or translation by Dr. J. Cheston Morris, p. 198, Philad., 1856. SIGNS OF PREGNANCY—QUICKENING. 503 much evidence prior to the period of quickening; but, after this, the examination, by what the French term the mouvement de ballottement, may indicate the presence or the contrary of a foetus in utero. This mode of examination consists in passing the forefinger of one hand into the vagina,—the female being in the erect attitude,—and giving the foetus a sudden succussion by means of the other hand placed on the abdomen. In this way, a sensation is communicated to the finger in the vagina, which is often of an unequivocal character. During the latter months, the cervix uteri becomes progressively shorter. The application of the stethoscope has been advantageously used as a means of discrimination in doubtful cases. By applying this instru- ment to the abdomen of a pregnant female, after the fifth month, the pulsations of the fcetal heart are audible. This instrument may also indicate when the pregnancy is multiple, by the distinct pulsations of two or more hearts; according as it is double, triple, &c. It would appear, however, that auscultation affords but two main signs of preg- nancy,—the pulsations of the fcetal heart, and a murmur, which, accord- ing to some, should, correctly speaking, be designated "uterine souffle or murmur." This murmur has been supposed to take place in the uterine artery, which serves for the nutrition of the placenta, and even to indicate the situation of the placenta; others have considered, that it is not connected with the placenta, but depends upon the increased vascularity and peculiar arrangement of the uterine vessels during the gravid state; but it has been questioned whether it be ever produced except by pressure on the maternal vessels. It is, indeed, positively stated, that the sound has been heard in cases of uterine and other tumours where there was no pregnancy; and in one case of fibrous tumour of the uterus, the author certainly heard it distinctly. In addition to the placental or uterine murmur and the sounds of the foetal heart, a third sound is occasionally heard, and one which is con- sidered to be seated in the umbilical cord. This has been termed the "funic bellows' sound." It is of the bellows species; is synchronous with the first sound of the foetal heart, and appears to depend upon a diminution in the caliber of the umbilical arteries, either through pres- sure, or stretching of the funis, or both combined. It is affirmed, too, by Prof. Nagele, that the movements of the foetus may be distinguished by the stethoscope at a very early period of pregnancy. The pulsations of the fcetal heart vary from 120 to 180 in the minute. Nagele1 affirms, that he has occasionally found them,—momentarily however,—sink as low as 50 or 60. Professor Hamilton2 refers to various cases, in which Drs. Sidey and Moir attended particularly to the action of the fcetal heart previous to breathing, in all of which its beats were 60 or less in a minute, before the establishment of respira- tion. Professor Hamilton affirms, that almost half a century had then elapsed since he remarked, that in infants which did not breathe upon birth, but in which the pulsation of the cord continued, the action of the heart did not exceed 60 pulsations in the minute till breathing took place, and then it became so frequent that it could not be numbered. 1 Dublin Journal of Medical Science, Jan., 1838. 2 Practical Observations on Various Subjects relating to Midwifery, American Medical Library edition, part i. pp. 51, 97, and part ii. p. 123, Philad., 1837-8. 504 GENERATION. This led him to take every opportunity—when he had occasion to intro- duce his hand into the uterus to extract the infant—to endeavour to ascertain the action of the heart before birth, and he in no instance discovered it to be more frequent than in the still-born infant whose cord pulsates. Yet neither Dr. Hamilton, nor any one of the gentle- men referred to, denies that pulsations, which have been referred to the fcetal heart, are heard by the stethoscope, varying from 120 to con- siderably upwards in the minute. The truth would seem to be, that in the cases examined by Professor Hamilton, owing to the influence of the parturient efforts on the innervation, and through it on the circu- lation of the foetus, the pulsations of the fcetal heart were unusually depressed; but in every case, he would, doubtless, have found them isochronous with those of the umbilical cord, had he made the experi- ment. It is obvious, indeed, that they must be so, seeing that the umbi- lical arteries are but a part of the circulatory apparatus of the fcctus. In a case observed, at the author's request, by Dr. Vedder, then resi- dent physician at the Philadelphia Hospital, it was noticed, that whilst the uterus was quiescent, the pulsations of the fcetal heart numbered 140 per minute; but that immediately succeeding a pain they were only 96, and gradually rose to 140. After delivery, the cord and foetal heart beat respectively 134 in the minute.1 Von Iloefft,2 of St. Petersburg, has seen the influence of uterine contraction on the circulation of the foetus exhibited in the most marked manner. During slight pains, the pulsations of the fcetal heart continue, but during more violent contrac- tions, especially after the discharge of the waters, they are wholly interrupted, so that the foetus may be presumed to be in a state of tem- porary asphyxia in the last periods of labour, and great danger may threaten it if the pains continue for a long time without interruption. The remarks of Professor Hamilton ought, therefore, to have no weight with the observer. They were imperfect, inasmuch as the pul- sations of the fcetal heart were not attended to, whilst he numbered the beats of the cord; and, consequently, they conflict in no respect with the observations of other obstetrical physiologists, which show, that the sounds usually heard during pregnancy, and referred to the fcetal heart, are actually owing to the pulsations of that organ. A case of triplets has been published in which the pulsations of three distinct foetal hearts were clearly detected. Lastly; many uneasy feelings, attendant upon gestation, are owing to the increased size of the uterus. These occur more especially during the latter half of pregnancy. The parietes of the abdomen may not yield with the requisite facility, so that pain may be experienced, espe- cially at the part where the soft parietes join the false ribs. The pres- sure of the uterus upon the vessels and nerves of the lower extremities occasions enlargement of the veins of the legs; transudation of the serous part of the blood into the areolar tissue, so as to cause consider- able swelling of the feet and ankles; numbness or pricking of the lower limbs, and the most violent cramps, especially when the female is in the recumbent posture, so that she may be compelled to rise suddenly from bed several times in the course of the night. The same pressure 1 American Medical Intelligencer, Jan. 15, 1839, p. 311. 2 Ibid., April 15, 1839, p. 31; also, Neue Zeitschrift fiir Geburtskunde, B. vi. S. 1. DURATION OF PREGNANCY. 505 exerted on the bladder and rectum, especially during the latter months, brings on a constant desire to evacuate the contents of those reservoirs. h. Duration of Pregnancy. The duration of human pregnancy has given rise to much discussion amongst medico-legal and obstetrical physiologists ; and opinions still fluctuate. In the years 1825-6, a case occurred before the House of Lords, which exhibits this discordance in a striking point of view. It was the Gardner Peerage cause, in which the principal accoucheurs of the British metropolis,—including Sir Charles M. Clarke, Drs. Bleg- borough, D. Davis, A. B. Granville, Conquest, Merriman, Hopkins, Blundell, and Power,—were examined. Of seventeen medical gentle- men, who gave evidence, five maintained the opinion, that the period of human utero-gestation is limited to about nine calendar months,—from thirty-nine to forty weeks, or from two hundred and seventy to two hundred and eighty days,—and of course considered it to be an impos- sibility, that the claimant could have been the product of a three hun- dred and eleven days' gestation. On the other side, of twelve medical gentlemen, all of whom appeared to agree that nine calendar months is the usual term of utero-gestation, most of them maintained the pos- sibility, that pregnancy might be protracted to nine and a half, ten, or even eleven calendar months, and were, of course, in favour of the claimant in the cause.1 The difficulty, that arises in fixing upon the precise term, is owing to the impracticability, in ordinary cases, of detecting the time of con- ception. But few cases exist where conception can be dated from a single coitus.2 An opportunity occurred, however, to Dr. Montgomery,3 for observing the term of utero-gestation under circumstances admitting of no dispute. A lady, who had been for some time under his care, in consequence of irritable uterus, went to the seaside at Wexford, in the month of June, leaving her husband in Dublin. They did not meet again until the 10th of November, when he went to visit her, and, being engaged in a public office, returned to town on the following day. Con- ception followed his visit, and before the end of the month she began to experience some of the signs of pregnancy, and on the 28th of January she quickened. Her last menstruation had occurred on the 18th of October, or twenty-three days before the visit of her husband; and on the 17th of August she was delivered. Parturition in this case occurred exactly two hundred and eighty days from the time of con- ception. The sensations of the female are fallacious guides; and, accordingly, as has been previously remarked, she is usually in the habit of reckon- ing from ten days after the disappearance of the catamenia; but impreg- nation might have taken place on the very day after their cessation, or 1 The Medical Evidence, relative to the Duration of Human Pregnancy, as given before a Committee of the House of Lords, in 1825 and 1826, with notes, by Robert Lyall, M. D., Lond., 1826. 2 For some such, see Guy, Principles of Forensic Medicine, P. 1, p. 167, London, 1843, and Taylor, Medical Jurisprudence, 3d Amer., by Dr. E. Hartshorne, p. 468, Philad., 1850. 3 An Exposition of the Signs and Symptoms of Pregnancy, &c, p. 257, Lond., 1837. 506 GENERATION. not until a day prior to the subsequent period; so that, in this way, an error of at least ten days may occur in the estimate; and again, it does not always happen, that the menstruation, immediately succeedino- ia arrested. The period of quickening, which generally happens about the eighteenth week of utero-gestation, does not afford us more positive evidence, seeing that it is liable to vary; being experienced by some females earlier, and by others somewhat later. We are, however justified in stating, that the ordinary duration of human pregnancy is ten lunar months or forty weeks; but we have no less hesitation in affirming, that it may be protracted, in particular cases, much beyond this. We find in animals, where the date of impregnation can be rigidly fixed, and the usual term determined without difficulty, that numerous cases are met with in which the period is protracted, and there is no reason to doubt, that the same thing happens to the human female. Earl Spencer has communicated the results of his observations on cowa for a number of years to the English Agricultural Society.1 Of 704, 314 calved before the 284th day, and 310 after the 285th; so that the probable period of gestation, he thinks, ought to be considered 281 or 285 days, and not 270, as stated in the book upon Cattle, published under the superintendence of the Society for the Diffusion of Useful Knowledge. The extremes in his observations were 220 and 313 days. In the observations of Mr. C. N. Bement, of Albany, cited by Dr. T. R. Beck,2 the extremes in sixty-two observed cases were 213 and 336. Mr. Bement, however, doubts the accuracy of the first, for in no other instance did the period fall below 260 days. The observations of Earl Spencer3 have suggested an interesting question in regard to man. He noticed, that cows in calf to a par- ticular bull belonging to him carried their calves about four days longer than those in calf to any other bull;—the average period of gestation being in them 290^ days. In a case detailed by Dr. Dewees,4 an opportunity occurred for dating with precision the time of fecundation. The case is likewise interesting in another respect, as demonstrating, that fecundation does not ne- cessarily arrest the succeeding catamenial discharge. The husband of a lady, who was obliged to absent himself many months, in conse- quence of the embarrassment of his affairs, returned one night clan- destinely,—his visit being known only to his wife, her mother, and Dr. Dewees himself. The lady was, at the time, within a week of her men- strual period; and, as the catamenia appeared as usual, she was induced to hope, that she had escaped impregnation. Her catamenia did not, however, make their appearance at the next period; the ordinary signs of pregnancy supervened; and in nine calendar months and thirteen days from the visit of her husband, she was delivered. In his evidence before the House of Peers, in the case before alluded to, Dr. Granville stated his opinion, that the usual term of utero-gestation is as we have given it; but he, at the same time, detailed the case of his own lady, in whom it had been largely protracted. Mrs. Granville passed, her menstrual period on the 7th of April, and on the 15th of August fol- 1 Journal of the English Agricultural Society, part ii., 1839. 2 American Journal of the Medical Sciences, Oct., 1845, p. 520. 3 Hall, Lond. Med. Gazette, May 6, 1842. * A Compendious System of Midwifery, 10th edit., p. 130, Philad., 1843. DURATION OF PREGNANCY. 507 lowino- she quickened;—that is, four months and six or seven days afterwards. In the early part of the first week in January her confine- ment was expected, and a medical friend desired to hold himself in readiness to attend. Labour pains came on at this time, but soon passed away; and she went on till the 7th of February, when labour took place, and was speedy. The child was larger and stronger than usual, and was considered by Dr. Granville,—as well as by Dr. A. T. Thomson, Professor of Materia Medicain the University of London,—to be a ten months' child. Now, if, in this case, we calculate, that conception occur- red only the day before the interruption of menstruation, three hundred and six days must have elapsed between impregnation and birth; and if the middle period between the last menstruation and the interruption be taken, the interval must have been three hundred and sixteen, or three hundred and eighteen days. A similar case has been related by Dr. R. H. Moll vain,1 of North Carolina. A woman, of character above suspicion, on the 1st of July, 1847, had intercourse with her husband, whose business had compelled him to absent himself for more than a year in a distant State. On the nights of the 2d, 3d, and 4th of July, the intercourse was repeated; but not subsequently. On the 23d of April, 1848, she was delivered of a child, which weighed nine pounds. Now, if fecundation had occurred on the 1st of July, the duration of preg- nancy must have been 296 days; if on the 4th, 293 days. Dr. Mcllvain adds, that the large size of the child was in favour of gestation having been longer than usual. The woman had borne three children pre- viously, none of which weighed more than eight pounds. Of recorded cases of single coitus, which are, of course, most to be relied on, Dr. James Reid2 found 293 days to form the longest period, or eighteen days beyond what he has deemed to be the average dura- tion of pregnancy in the human female; and he remarks it to be a coincidence with the results of Lord Spencer's tables, that of the 764 cows, the greatest excess beyond the average term of gestation in them —285 days—was also eighteen days. The limit, to which the protraction of pregnancy may possibly extend, cannot be assigned. It is not probable, however, that it ever varies largely from the ordinary period. The University of Heidelberg allowed the legitimacy of a child, born at the expiration of thirteen months from the date of the last connubial intercourse; and a case was decided by the Supreme Court of Friesland, by which a child was admitted to the succession, although it was not born till three hundred and thirty- three days from the husband's death; or only a few days short of twelve lunar months. These are instances of judicial philanthropy, and, per- haps, we might add. credulity. Still, although extremely improbable, we cannot say that they are impossible. This much, however, is clear, that real excess over two hundred and eighty days is by no means fre- quent; and we think, in accordance with the civil code now in force in France, that the legitimacy of an infant, born three hundred days after the dissolution of marriage, may be contested; although we are by no means disposed to affirm, that if the character of the woman be irre- proachable, the decision should be on the side of illegitimacy. Pro- 1 American Journal of the Medical Sciences, July, 1848, p. 247. 1 Lancet, July 20,1850; and Amer. Journ. of the Medical Sciences, Oct., 1850, p. 522. 508 GENERATION. fessor Hamilton, indeed, says he is "quite certain," that the term allowed by the French code is too limited, and is inclined to regard ten calendar months, which he believes to be the established usa«e of the Consistorial Court of Scotland, as a good general rule, liable to exceptions upon satisfactory evidence that menstruation had been ob- structed for a certain period.1 In the year 1844, a case of gestation protracted to 317 days was admitted in Cambria county, Pennsylvania;2 and in 1846, another of 313 days at the Lancaster Quarter Sessions.3 The charge of the pre- siding judge, Ellis Lewis, in the latter case, was sound and satisfactory. Whilst he expressed the belief, that protracted gestation for the period of 313 days is unusual and improbable, he regarded it as not impos- sible; but properly added "that the evidence to establish the existence of such a departure from the usual period should be clear and free from doubt." A like uncertainty exists as to the earliest period at which a child is viable or capable of carrying on an independent existence. The period is generally fixed at near the end of the seventh month; but children have lived for some time, that have been born earlier. Much evidence was brought forward in a case in Scotland, to show that it is possible for a child that was born at the conclusion of 24 weeks of utero-ges- tation to live some months. In that case, the Presbytery decided in favour of the legitimacy of one born alive within 25 weeks after mar- riage.4 An interesting case has been published in this country by Dr. Ship- man.5 A woman, who considered herself to be at the commencement of the sixth month of utero-gestation, was prematurely delivered in consequence of a fall. The appearance of the child indicated no farther advance. It was barely alive, with little motion, and was too feeble to cry; had no nails; no hair; and the cranium was imperfectly ossified. At the end of the seventh week, it was weighed for the first time, when its weight was found to be one pound ten ounces, which Dr. Shipman thinks was probably the true weight when it was born. When ten months old it weighed ten pounds eight ounces, and was lively, playful, and healthy. It was not measured at the time of birth, and no hopes of its living were entertained.6 The difficulty, in such cases, of fixing the exact date of conception must necessarily render all computation in regard to the precise age of the child uncertain.7 1 Op. cit., Amer. Med. Library edit., p. 59. 2 Commonwealth vs. Jeremiah Wilson Porter; indicted for Fornication and Bastardy, January Term, 1844; reported by Dr. A. Rodrigue, in American Journal of the Medical Sciences, Oct., 1845, p. 338. 3 Commonwealth vs. Elijah F. Hoover; in Medical Examiner, for June, 1846, p. 381; and in American Journal of the Medical Sciences, for Oct., 1846, p. 536. 4 Lond. Med. Gaz., xvii. 92. 5 American Journal of the Med. Sciences, April, 1843, p. 499. 6 For the case of a child born at the commencement of the sixth month, and reared, see Barker, American Journal of the Medical Sciences, Jan., 1851, p. 257; and for other cases, see Taylor, Medical Jurisprudence, 3d Amer. edit., by Dr. E. Hartshome, p. 403, Philad., 1853. 7 See, on all this subject, Prof. Simpson, Edinb. Monthly Journal of Med. Science, July, 1853, p. 50 ; and Obstet. Memoirs and Contrib., p. 329, Edinb., 1855, or Amer. edit., Philad., 1855. PARTURITION. 509 i. Parturition. At the end of seven months of utero-gestation, and even a month earlier, the foetus is capable of an independent existence; provided, from any cause, delivery should be hastened. This is not, however, the full period, and although labour may occur at the end of seven months, the usual course is for the foetus to be carried until the end of about ten lunar months. If it be extruded prior to the period at which it is able to maintain an independent existence, the process is termed abortion or miscarriage; if between this time and the full period, it is called premature labour. From certain records, abortion or premature labour has been estimated to occur, on the average, once in 78| cases. In the Gebaranstalt of Vienna, the inmates of which are chiefly unmarried, the ratio appears to be more than double, or 1 in 38-13.1 With respect to the causes, that give rise to the extrusion, we are in utter darkness. It is in truth as inexplicable as any of the other instinctive operations of the living machine. Yet although this is generally admitted, the discussion of the subject occupies a consider- able space in the works of some obstetrical writers. Our knowledge appears to be limited to the fact, that when the foetus has undergone a certain degree of developement, and the uterus a corresponding dis- tension and organic change, its contractility is called into action, and the uterine contents are beautifully and systematically expelled. Nor can we pronounce upon the degree of distension, nor appreciate the organic changes that shall give occasion to the exertion of this contrac- tile power. At times, it supervenes after a few months of utero-gesta- tion so as to produce abortion: at others, it happens when the foetus is just viable; and at others, again, and in the generality of cases, is not elicited until the full period. In cases of twins the uterus will admit of still greater distension before its contractility is aroused. It has been maintained by M. Berthold,2 Dr. Tyler Smith,3 and M. Leray,4 that parturition, like menstruation, is an ovarian phenomenon; that the muscular excitability of the uterus at the full period is depen- dent upon ovarian excitement; and that the supervention of its expul- sive contractions on the 280th day, or thereabouts, after conception, is a reflex phenomenon, of which the eleventh periodical access of ovarian excitement, corresponding to the eleventh menstrual period, is the exciting cause; but the evidence brought forward in support of the position is far from establishing it. The hypothesis would require a more extensive inquiry into the phenomena, presented not only by the human female, but by animals, in which the period of parturition would have to be a multiple of the period of oestruation or heat; for it has been before remarked that the oestruation of animals and menstru- ation have been regarded as the same form of ovulation. Dr. Smith affirms, that observation of animals has tended to confirm the view; 1 Wilde, Austria, &c, p. 222, Dublin, 1843. 2 Comptes Rendus, 27 Mai, 1844; and Archives Generates de Medecine, Juin, 1844. 3 Parturition and the Principles and Practice of Obstetrics, Amer. edit., p. 127, Philad., 1849. 4 Cited in London Lancet, Jan., 15 1848. 510 GENERATION. but he does not furnish the facts in sufficient number to lead to any- thing like conviction of the truth of the hypothesis. On the other hand, Dr. Carpenter considers the hypothesis to be dis- tinctly negatived by the following FiS* m- facts. First. The period of gesta tion, although commonly a multiple of the menstrual interval, is by no means constantly so; the for- mer often remaining normal, when the latter is shorter or longer than usual. Secondly. Parturient efforts take place in the uterus, notwith- standing the previous removal of the lower part of the spinal cord. Thirdly. The removal of the ova- ries in the latter part of gestation does not interpose the least check to the parturient action, as Profes- sor Simpson, of Edinburgh, has experimentally ascertained. Dr. Carpenter forcibly adds, that he considers himself fully justified Natural Labour. in asserting that " this hypothesis does not possess the slightest claim to be entertained as even & possible one."1 In regard to the action of the muscles specially concerned in the process, it would seem, that the diaphragm and abdominal muscles are excited to action through an excitor influence conveyed from the ute- rus to the spinal cord; whilst the contractions of the uterus take place independently of all connexion with the nervous centres,—like the peristole of the intestines, and the systole of the ventricles of the heart. The foetus has been observed to be expelled after the cessation of the respiratory movements of the mother. This, as has been suggested,2 has probably occurred in consequence of the uterine fibres retaining their power of contraction longer than those of muscles supplied by cerebro-spinal nerves. A day or two preceding labour, a discharge is occasionally ob- served from the vagina of a mucous fluid more or less streaked with blood. This is termed the show, because it indicates the commence- ment of dilatation of the neck, or mouth of the womb,—the forerunner of labour or travail. The external organs at the same time become tumid and flabby. The orifice of the uterus, if an examination be made, is perceived to be enlarging ; and its edges are thinner. Along with this, slight grinding pains are experienced in the loins and abdo- men. After an uncertain period, pains of a very different character come on, which commence in the loins, and appear to bear down towards the os uteri. These are not constant, but recur at first after long intervals, and subsequently after shorter,—the body of the uterus 1 Brit, and For. Med.-Chir. Rev., July, 1849, p. 1 ; and Carpenter, Principles of Hu- man Physiology, Amer. edit., p. 776, note, Philad., 1855. 2 Carpenter, Human Physiol., p. 153, Lond., 1842. PARTURITION. 511 manifestly contracting with great force, so as to press the ovum down against the mouth of the womb, and dilate it. In this way, the mem- branes protrude through the os uteri with their contained fluid, the pouch being occasionally termed bag of waters. Sooner or later, the membranes give way; the waters are discharged, and the uterus con- tracts so as to embrace the body of the child, which was previously impracticable, except through the medium of the liquor amnii. At the commencement of labour, the child's head has not entered the pelvis" the occiput being generally towards the left acetabulum; but when the uterine contractions become more violent, and are accom- panied by powerful efforts on the part of the abdominal muscles, the head enters the pelvis; the mouth of the womb becomes largely dilated, and the female is in a state of agitation and Fig. 450. excitement, owing to the violence of the ef- forts and the irresistible desire she has of assist- ing them as far as lies / in her power. When •' the head has entered ■ the pelvis, in the posi- \ tion in which the long diameter corresponds to the long diameter of the pelvis, it describes, late- rally, an arc of a circle, the face passing into the hollow of the sa- crum, and the occiput behind the arch of the pubis. By the continu- ance of the pains, the head presents at the vulva. The pains now become urgent and fore- Rotation of the Head in its exit. ing. The os coccygis is pushed backwards, and the perineum is distended,—at times so con- siderably as to threaten, and even undergo laceration; the anus is also forced open and protruded; the nymphae and carunculae of the vagina are effaced; the labia separated, and the head clears the vulva, from the occiput to the chin, experiencing a vertical rotation as depicted in Fig. 450. When the head is extruded, the shoulders and rest of the body readily follow on account of their smaller dimensions. The child, however, still remains attached to the mother by the navel-string, which has to be tied, and divided at a few fingers' breadth from the umbili- cus. After the birth of the child, the female has generally a short interval of repose; but after a time, slight bearing down pains are experienced, owing to the contraction of the uterus for the separation of the placenta and membranes of the ovum, called the secundines or after-birth. 512 GENERATION. The process of parturition is accomplished in a longer or shorter time in different individuals, and in the same individual in different labours, according to the particular conditions of the female and foetus. The parts, however, when once dilated, yield much easier afterwards to similar efforts, so that the first labour is generally the most pro- tracted. After the separation of the secundines, the female is com- monly left in a state of debility and fatigue; but this gradually disap- pears. The uterus also contracts; its vessels become tortuous, small and their orifices are plugged up. For a short time, blood continues to be discharged from them; but as they become obliterated by the return of the uterus to its usual size, the discharge loses its sanguineous character, and is replaced by one of a paler colour, called lochia, which gradually disappears, and altogether ceases in the course of two or three weeks after delivery. For a day or two after delivery, coagula of blood form in the interior of the uterus, especially in the second and subsequent labours, which excite the organ to contraction for their expulsion. These contractions are accompanied with pain, and are called after-pains; and as their object is the removal of that which interferes with the return of the uterus to its proper dimensions, it is obvious that they ought not to be officiously interfered with. Whilst the uterus is contracting its dimensions, the other parts gra- dually resume the condition they were in prior to pregnancy; so that, in the course of three or four weeks, it may be impracticable to pro- nounce positively whether delivery has recently taken place or not. The presence of shining broken streaks, like the remains of cracks, in the skin of the abdomen, caused by previous distension of the abdo- minal parietes, has been regarded as a sign of some value of former delivery; but they are often wanting where delivery has really taken place; and it will be readily understood, that any cause of distension may produce them. These marks are sometimes accompanied by a brown line, extending from the pubis to the umbilicus ;l and accom- panying this dark abdominal line, Dr. Montgomery, in a few instances, has observed another appearance of a similar kind, which consists of a dark coloured circle or areola surrounding the umbilicus, extending in breadth about a quarter of an inch all around it, and generally, but not always, varying in depth of tint according to the colour of the hair, eyes, and skin of the woman. Unlike the mammary areola, there is no turgescence or elevation of it above the surface of the surrounding skin, nor are there any prominent follicles upon its disk. Whether it be ever produced under circumstances unconnected with pregnancy remains to be determined by farther observation. Labour, as thus accomplished, is more deserving of the term in the human female than in animals; and this is partly owing to the large size of the fcetal head, and partly to the circumstance, that in the ani- mal the axis of the pelvis is the same as that of the body; whilst in the human female, the axis of the brim, as represented by the dotted straight lines in Fig. 450, forms a considerable angle with that of the 1 Montgomery, Signs and Symptoms of Pregnancy, 6th edit., p. 171, Lond. 1842; Dublin Journal of Med. Science, May, 1844, p. 298: see, also, Dr. R. Turner, Lond. and Edinb. Monthly Journal of Med. Science, Aug., 1842, and Sept., 1844; and Dr. J. R. Cormack, Ibid., Feb., 1S44. PARTURITION. 513 451. outlet. In rare cases, the child is extruded without labour-pains. The author was called in the night to a female, who declared to him, that she was awakened by a slight abdominal uneasiness, when she found both the child and secundines expelled; and other cases of a like kind are on record. These facts should be borne in mind in cases of alleged infanticide. The duration of labour varies accord- ing to numerous circumstances. There is reason to believe, that it is more tedious in civilized than in savage life; and in colder than in warmer climates. The following table is the result of 311 observed cases in the Edinburgh Boyal Maternity Hospital, as reported by Professor Simpson.1 It reads thus:— the whole labour was completed in one hour in four cases; in two hours in four Cases, and SO OU. Breech Presentation. Duration in hours. Whole labour. Duration in hours. Whole labour. 1 4 13 23 2 4 14 14 3 7 15 8 4 16 16 6 5 17 17 6 6 16 18 8 7 28 19 10 8 21 20 3 9 17 25 22 10 20 30 12 11 20 35 5 12 12 Above 36 14 Fig. 452. The position of the child—with the face behind and the occiput before—constitutes the usual presenta- tion in natural labour. Of twelve thousand six hundred and thirty-three children born at the Hospice de la Maternite of Paris, twelve thousand one hundred and twenty, according to M. Jules Cloquet, were of this presenta- tion; sixty-three had the face turned forward; one hundred and ninety-eight were breech presentations (Fig. 451); in one hundred and forty-seven the feet presented; and in three, the knees. All these, however, are cases in which la- bour can be effected without assistance; the knee and feet presentations being identical—as regards the process of de- Arm Presentation. 1 Monthly Journal and Retrospect of the Medical Sciences, Nov., 1848, p. 333. VOL. II.—33 • 514 GEsNERATION. livery—with that of the breech. But, whenever any other part of the foetus presents, the position is unfavourable and requires that the hand should be introduced into the uterus, with the view of bringing down the feet, and converting the case into a foot presentation. The mar- ginal figure of a presentation of the right superior extremity suffi- ciently shows, that labour could not be accomplished without the efforts of art. The following table, drawn up from data furnished by M. Yelpeau,1 shows the comparative number of presentations, according to the expe- rience of the individuals mentioned. TABLE EXHIBITING THE RATIO OF PRESENTATIONS IN 1000 CASES. According to H3 no C3 3iS h e 3 2Ja So o Hi 6"o« X * 0 n Regular, or of the vertex, 924 944 969 933 933 911 980 I. Occipito-anterior, 908 944 910 895 a. Occipito-cotyloid, (left) 760 717 537 Do. (right) • 179 209 6. Occipito-pubian, 0-29 II. Occipito-posterior, . 9-4 9 a. Fronto-cotyloid (left) . 5-3 7-3 b. Do. (right) 4-4 2-9 Face presentation, . . 2-2 2-6 3-6 4-6 8-8 Mento-iliac (right) . . 2-6 Of the pelvis, .... 36 28 29 36 47 29 Of the foot,..... 12-7 9-4 14 10-3 Of the knees, .... 0-19 0-40 Of the breech, .... 23 13 18 22 19 Of the trunk, .... 4-6 5.3 4-8 Requiring Forceps, . . 6-6 4-7 4-6 3.4 3-6 5-7 16 4-7 7.8 7-2 5-9 C cnhalotom v 3-3 5-2 4-77 0-53 2-4 1-5 In twin labours, the children may both present by the head; or one by the head and another by the breech, or both be footling cases. It is found, that the period of the twenty-four hours has some in- fluence upon the process of parturition;—about five children being born during the night for four during the day. Of 2,019 births, ac- cording to Wedl,2 780 occurred from 11 at night until 7 in the morn- ing; 680 from 7 in the morning until 3 in the afternoon; and577 from 3 until 11 at night. The parturient and child-bed condition is not devoid of danger to the female; yet the mortality is less than is generally perhaps imagined. In some of the great lying-in institutions it has been enormous; and in the Gebaranstalt of Vienna is still estimated at 1 in 30*87! The number of deaths, during labour, and subsequently, connected there- with, has been stated to be in Berlin as 1 in 152; in Konigsberg, 1 in 168; and in Wirtemberg, 1 in 175;—a proportion much less than 1 Traite Elementaire de l'Art des Accouchemens, Paris, 1829; or Meigs's translation, 2d edit., Philad., 1838. 2 Canstatt's Jahresbericht, 1853, S. 236. LACTATION. 515 Fig. 453. Twin case. during the last century. In 1475 women delivered under the super- intendence of the Edinburgh Boyal Ma- ternity Hospital, eleven deaths oc- curred, or 1 in 134.1 Dr. Collins2 states, that of 16,414 women, delivered in the Dublin Lying-in Hospital, 164 died, being in the proportion of 1 in 100; and if, he observes, we deduct from this number the deaths from puerperal fever, which may be considered accidental, the proportion becomes greatly diminished, or 1 in 156 deliveries ; and again, if we subtract the deaths from causes not the results of child-birth, the mortality, from effects arising in consequence of partu- rition, is vastly reduced to 1 in 244. In the year 1839, childbirth was fatal to 2915 women throughout England and Wales. Of 1,000,000 females living, 368 died from this cause in 1838, and 372 in 1839. About 5 births in 1,000, it was estimated, were fatal to the mother.3 In 1840, the ratio was greater, or about 1 in 187.4 It has been already remarked, that these fatal cases occur more frequently in male than female births. From the returns of Drs. Clarke and Collins there are reports in the Dublin Hospital of the sex of the child in 368 cases in which the mother died from labour or its consequences. In 231, the child was male; in 137 female; or the proportion of males to females was as 168 to 100. Taking these statistical facts as data, Prof. Simpson,5 of Edinburgh, infers, that annually, in Great Britain, " the valuable lives of 500 mothers (to speak within the terms) are lost in childbirth," through the influence and agency of the sex and size of the male infant. The further details on the subject of parturition belong more appro- priately to obstetrics. j. Lactation. When the child has been separated from the mother, and continues to live by the exercise of its own vital powers, it has still to be depend- ent upon her for nutriment adapted to its tender condition. Whilst in utero, this nutriment consists of fluids placed in contact with it; but after birth a secretion serves the purpose, which has to be received into the stomach and undergo the digestive process. This secretion is the milk. It is prepared by the mammae or breasts, the number, size, and situation of which are characteristic of the human species. In- stances are, however, on record, of three or more distinct mammae in 1 Monthly Journal and Retrospect of the Medical Sciences, November, 1848, p. 337. 1 Practical Treatise on Midwifery, p. 366, Lond., 1835. 3 W. Farr, in Third Annual Report of the Registrar-General of Births, Deaths and Marriages in England, p. 74, London, 1841. * W. Farr, in Fourth Annual Report, &c, &c, p. 219, Lond., 1842. 5 Edinb. Med. and Surg. Journal, Oct., 1844. 516 GENERATION. the same individual. Two such are described by Dr. G. CM. Roberts of Baltimore.1 At times, there are two nipples on one breast. Three cases of the kind are given by Tiedemann, and one by Dr. Chowne**1 and a case has been recorded by M. Marotte,3 in which there was a supernumerary mamma in each axilla. In some instances the super- numerary breasts have been on other parts of the body. Each breast contains a mammary gland, surrounded by the fat of the breast, and resting on the pectoralis major muscle. It is formed of several lobes, united by somewhat dense areolar tissue, and consist- ing of smaller lobules, which seem, again, composed of round granula- Fig. 454. Milk Ducts in Human Mamma. The ducts are filled with wax. tions, of a rosy-white colour, and about the size of a poppy-seed. These granules or acini, according to Reil,4 cannot be distinguished in the mammae of the virgin. The glandular granules give origin to ex- cretory ducts, called tubuli lactiferi seu galactophori, which are tortuous, extensible, and transparent; and enlarge and unite with each other, so that those of each lobe remain distinct from, and have no communica- 1 Baltimore Medical and Surgical Journal, ii. 497, Baltimore, 1834. 8 Lond. Lancet, July 2, 1842, p. 465. 8 Archives Generates de Medecine, Janvier, 1850, p. 114. 4 Schlemm, art. Briiste, in Encyclop. Worterb. der Medicin. Wissenschaft., vi. 332 Berlin, 1831. LACTATION. 517 tion with, the ducts of any other lobe. All these finally terminate in sinuses or reservoirs, near the base of the nipple, which are fifteen or Fig. 455. Fig. 456. The Mammary Gland after the removal of the skin, as taken from the subject three days after delivery. 1. The surface of the chest. 2. Subcutaneous fat. 3. The skin covering the gland. 4. Circumference of the gland. 5. Its lobules separated by fat. 6. The lactiferous ducts converging to unite in the nipple. 7. The nipple slightly raised, and showing the openings of the tubes at its extremity. A vertical section of the Mam- mary Gland, showing its thick- ness and the organs of the lactiferous ducts. 1, 2, 3. Its pectoral surface. 4. Sec- tion of the skin on the surface of the gland. 5. The thin skin covering the nipple. 6. The lobules and lobes com- posing the gland. 7. The lactiferous tubes coming from the lobules. 8. The same tubes collected in the nipple. eighteen in number, and open on the nipple, without having any com- munication with each other. The size and shape of the breast are Fig. 457. Commencement of Milk Ducts as ex- hibited in a mercurial injection. Fig. 458. mSam Ultimate Follicles of Mammary Gland. a, a. Secreting cells, b, b. The Nuclei. chiefly caused by the areolar tissue in which the mammary gland is situate: this is covered by a thin layer of skin, which is extremely soft and delicate; and devoid of folds. In the middle of the breast is the tubercle, called nipple, mammella or teat,—a prominence consisting of an erectile spongy tissue, differing in colour from the rest of the breast. The nipples do not project directly forwards, but forwards and out- wards, for wise purposes, which have been thus depicted by Sir Astley Cooper :•—'•' The natural obliquity of the mammella or nipple forwards and outwards, with a slight turn of the nipple upwards, is one of the most beautiful provisions in nature both for the mother and her child. 1 On the Anatomy of the Breast, p. 12, London^ 1840. 518 GENERATION. To the mother, because the child rests upon her arm and lap, in the most convenient position for sucking ; for if the nipple and breast had pro- jected directly forwards, the child must have been supported before her in the mother's hands in a most inconvenient and fatiguing position, in- stead of its reclining upon her side and arm. But it is wisely provided by nature, that when the child reposes upon its mother's arm, it has its mouth directly applied to the nipple, which is turned outwards to receive it, whilst the lower part of the breast forms a cushion upon which the cheek of the infant tranquilly reposes." The erection of the nipple, which is so manifest during the process of suckling, and can be readily produced by handling it, has been supposed to be owing to an arrangement similar to that of the corpora cavernosa penis, or to a venous circle surrounding the nipple;' but Sir Astley Cooper attributes it simply to an afflux of blood into the capillaries of the part. Around the nipple is the areola, which is of a rosy hue in youth but becomes darker in the progress of life, and the capillary system of which'is so delicate as to blush, like the countenance, under similar emotions. The changes, produced on the areola by gestation, have been already described. The skin, at the base of the nipple, and on its surface, is rough, owing to the presence of a number of sebaceous follicles, called by Sir Astley Cooper " tubercles of the areola," which secrete a fluid for the lubrication of the part, and for defending it from the action of the secretions from the mouth of the infant during lacta- tion. Numerous arteries, veins, nerves, and lymphatics,—the anato- mical constituents of organic textures in general,—enter into the composition of the mammae and nipples. The mammary gland of the male is analogous to that of the female, but much smaller. The secretion of milk is liable to longer intermissions than any other function of the kind. In the unmarried and chaste female, although the blood, whence milk is formed, may be constantly passing to the breast, no secretion takes place from it. It is only during gestation and some time afterwards, that, as a general rule, the necessary exci- tation exists to produce it. Yet although largely allied to the genera- tive function,—the mamma? undergoing their chief developement at puberty, and becoming shrivelled in old age,—the secretion may arise independently of impregnation; for it has been witnessed in the un- questioned virgin, the superannuated female, and even in the male sex. The fact as regards the unimpregnated female is mentioned by Hippocrates. M. Baudelocque2 states, that a young girl at AlenQon, eight years old, suckled her brother for the space of a month. Dr. Gordon Smith3 refers to a manuscript in the collection of Sir Hans Sloane, which gives an account of a woman, at the age of sixty-eight, who had not borne a child for more than twenty years, and nursed her grandchildren, one after another. Professor Hall, of the University of Maryland, related to the author the case of a widow, aged fifty, whom 1 Prof. Sebastian, Tijdschrift voor Natuurlijke Geschiedenis en Physiologie, door J. Van der Hoeven en W. H. de Vriese, 2de Deel, Bl. i., Amsterdam, 1835. 2 Art. d'Accouchement, i. 188, Paris, 1822. s Forensic Medicine, p. 484. LACTATION—IN UNIMPREGNATED FEMALES. 519 he saw giving suck to one of her grandchildren, although she had not had a child of her own for 20 years previously. The secretion of milk was solicited by putting the child to her breast during the night, whilst weaning it. Dr. Francis, of New York, describes the case of a lady, who, 14 years previously, was delivered of a healthy child after a natural labour. " Since that period," he remarks, " her breasts have regularly secreted milk in great abundance, so that, to use her own language, she could at all times easily perform the office of a nurse ;" and Dr. Kennedy,1 of Ashby de la Zouch, has described the case of a woman, who menstruated during lactation; suckled children uninter- ruptedly through the full course of forty-seven years, and, in her eighty-first year, had a moderate, but regular supply of milk, which was rich and sweet, and did not differ from that yielded by young and healthy mothers. In a note, with which the author was favoured by Dr. Samuel Jackson—formerly of Northumberland County, Pa., now of Philadelphia—a case is described of a lady, certainly above sixty- five years of age, who nursed one of her daughter's twins. She had not borne a child for many years, and was suddenly endowed with a fall flow of milk. A lady of Northumberland observed to Dr. Jackson, " that she could not but admire the beautiful fulness and contour of her bosom." Dr. Bichard Clarke,2 of Union Town, South Alabama, has recorded the case of a lady, who had never borne a child, and was requested to take charge of an infant during the illness of its mother. In the course of the night, the infant became restless and fretful, and the lady—to quiet it—put her nipple into its mouth. This was done from time to time, until the milk began to flow. An interesting fact, connected with this case, was, that sometime afterwards she conceived, and at the expiration of the usual term was delivered of a fine child. Dr. Clarke refers to other cases, which would appear to show, in another form, the intimate and mysterious sympathy that exists between the mammae and the uterus. Dr. Green3 has published the case of a lady, aged 47 years, the mother of four children, who has had abundance of milk for 27 years past. A period of exactly four years and a half occurred between each birth, and the children were permitted to take the breast till they were running about at play. At the time when Dr. Green wrote, she had been nine years a widow, and was obliged to have her breasts drawn daily, the secretion of milk being so copious. In the Samoan group of islands, the mothers often suckle their children until they are six years old; and Captain Wilkes was informed of an instance where a woman gave nourishment to three children of different ages,—the eldest removing the youngest at times by force from the mother's breast.4 Dr. McWilliam5 states, that the inhabitants of Bona Vista are accustomed to provide a wet-nurse, in cases of emergency, in any woman who has once borne a child, and is still within the age of child-bearing, by continued fomentation of the mammae with a decoc- tion of the leaves of jatropha curcas, and by suction of the nipple. 1 Medico-Chirurgical Review for July, 1832. 2 American Medical Intelligencer, April 16,1838, p. 19. 9 New York Journal of Medicine and Surgery, September, 1844. 4 Narrative of the United States Exploring Expedition, &c.,&c..ii. 138, Philad., 1845. 1 Report of the Niger Expedition, London Med. Gazette, Jan., 1847. 520 GENERATION. According to M. Desormeaux,1 some women are able to continue suckling almost indefinitely, provided the child be put to the breast. It is not uncommon, he says, in France, to see nurses suckle three children in succession, comprising a period probably of from 30 to 36 months; and cases are not rare where women have given suck for four years, and four years and a half. He saw a nurse from Normandy, who had suckled several children successively on the same milk for upwards of five years; and a lady, worthy of all credit, informed him, that she knew a woman who had nursed five children in succession, so that her lactation continued at least seven years. Mr. Erman2 found, that the Tunguzian women suckle their children for a very long period. In Garmaztakh, he saw a boy, four years old, frequently qui- eted with the milk, which more properly belonged to his youngest brother. He saw several similar examples amongst the Samoyed women, and learned from a medical gentleman in Tobolsk, that the Ostyok fisherwomen can give milk at all times, "almost like cows." But these, and cases of a similar nature, of which there are many on record,3 do not possess the same singularity as those of the function being executed by the male. We have, however, the most unquestion- able authority in favour of the occurrence of such cases. A bishop of Cork4 relates the case of a man who suckled his child after the death of his wife. Humboldt adduces one of a man, thirty-two years of age, who nursed his child for five months on the secretion from his breasts; Captain Franklin5 gives a similar instance; and Professor Hall, of the University of Maryland, exhibited to his obstetrical class, in the year 1827, a coloured man, fifty-five years of age, who had large, soft, well- formed mammae; rather more conical than those of the female, and projecting fully seven inches from the chest; with perfect and large nipples. The glandular structure to the touch seemed to be exactly like that of the female. This man, according to Professor Hall, had officiated as wet-nurse for several years in the family of his mistress; and he represented, that the secretion of milk was induced by applying the children, intrusted to his care, to the breasts during the night. When the milk was no longer required, great difficulty was experienced in arresting the secretion. It may be added, that his genital organs were fully developed. In the winter of 1849-50, an athletic man, twenty-two years of age, presented himself at the Clinic of the Jeffer- son Medical College of Philadelphia, whose left mamma, without any assignable cause, became greatly developed, and secreted milk co- piously.6 It appears, therefore, that the secretion of milk may be caused, independently of a uterus, by soliciting the action of the mam- mary glands: but that this is a mere exception to the general rule, according to which the secretion is as intermittent as gestation itself. It has been stated, as one of the signs of pregnancy, that the breasts 1 Art. Lactation, Diet, de Med., xxii. 425, Paris, 1838. 2 Travels in Siberia ; translated from the German by W. D. Cooley, ii. 527, London, 1848. 3 Elliotson's Blumenbach, 4th edit., p. 509, Lond., 1828. 4 Philos. Trans., xli. 813. 5 Narrative of a Journey to the Polar Sea, p. 157. 6 See a letter to the author by C. W. Hornor, in Medical Examiner, August, 1850. LACTATION—COLOSTRUM. 521 become enlarged and turgid, denoting the aptitude for the formation of milk; and it not unfrequently happens, that, towards the middle and later periods of pregnancy, fluid distils from the nipples. This fluid, however, as well Us that which flows from the breasts during the first two or three days after delivery, differs somewhat from milk, contain- ing more serum and butter, and less casein; and is conceived to be more laxative, so as to aid the expulsion of the meconium. The first milk is called colostrum, protogala, &c, and, in the cow, constitutes the biestings or beastings. Generally, about the third day after confine- ment, the mamma3 become tumid, hard, and even painful, and the se- cretion from this time is established, the pain and distension soon dis- appearing. The circumstances most worthy of note, connected with the colostrum of the cow, in a physiological point of view, are, accord- ing to Dr. John Davy1—who has carefully inquired into its chemical and other properties—the concentration of nutritive matter in it; the greater facility of its coagulation by rennet compared with older milk, and its greater power of resisting change when exposed to the action of atmospheric air,—qualities which, he thinks, fit it for the first food of the new being. Its ready coagulation may adapt it to the stomach, in which the gastric juice is probably at first in small quantity and feeble; and its power of resisting change,and remaining semi-fluid, may adapt a part of it to the intestines to promote the removal of the meco- nium ; whilst its concentration as nutritive matter may fit it to perform for the calf the same part, that the substance of the egg performs, which enters the intestines during the latter stage of fcetal develope- ment in birds, reptiles and fishes. AVhether the first milk of the human female possesses these characters has not been determined. It is hardly necessary to discuss the views of M. Kicherand,2 who considers the milk to be derived from the lymph; or of others, who derive it from the chyle; of M. Baspail, who is disposed to think, that the mammary glands are in connexion, by media of communication yet unknown, with the mucous surface of the stomach, and that they sub- tract from the alimentary mass the salts and organizable materials which enter into the composition of the milk; or of M. Girard of Lyons, who gratuitously asserts, that there is in the abdomen an apparatus of vessels,—intermediate between the uterus and mammae,—which continue inactive, except during gestation, and for some time after delivery; but, in those conditions, are excited to activity.3 All these notions are hypo- thetical; and there is no reason for believing, that this secretion differs from others as regards the kind of blood from which it is separated. The separation occurs in the tissue of the gland, and the product is received by the lactiferous ducts, along which it is propelled by the fresh secretion continuously arriving, and by the contractile action of the ducts themselves,—the milk remaining in the ducts and sinuses, until, at times, the mammas are greatly distended and painful. The excretion of the milk takes place at intervals. When the lac- tiferous ducts are sufficiently filled, a degree of distension and uneasi- ness is felt, which calls for the removal of the contained fluid. At 1 Transactions of the Medico-Chirurgical Society, 1845. 2 Nouveaux Eb'mens de Physiologie, 7eme edit., Paris, 1817. 3 Adelon, Physiologie de l'Homme, 2de edit.,iv. 141, Paris, 1839. 522 GENERATION. times, the flow occurs spontaneously; but, commonly, only when soli- cited either by sucking or drawing the breast,—the secretion under such circumstances being very rapid, and the contraction of the galac- tophorous ducts such as to project the milk through* the orifices in a thready stream. Milk is a highly nitrogenized fluid, composed of water, casein, sugar of milk, certain salts,—as chloride of sodium, phosphate, and acetate of potassa, with a vestige of lactate of iron and earthy phosphate,— and a little lactic acid. Cow's milk consists of cream, and milk pro- perly so called,—the cream consisting, according to Berzelius,1 of butter, 4*5; cheese, 3*5; whey, 92*0;—and the whey, of milk and salt, 4*4;— the milk containing wafer, 928*75;—cheese, with a trace of butter, 28*01; sugar of milk, 35*00; chloride of potassium, 1*70; phosphate of potassa, 0*25; lactic acid, acetate of potassa, and lactate of iron, 6*00; and phosphate of lime, 0*30. M. Kaspail2 defines milk to be an aqueous fluid, holding albumen and oil in solution by means of an alkali, or alkaline salt, which he suggests may be acetate of ammonia,—and, in suspension, an immense number of albuminous and oleaginous globules. The following table exhibits the discrepant results of the investigations of Brisson, Boyssou, Stip- riaan Luiscius and Bondt, Schiibler, and John, in 1000 parts of the milk of different animals—as given by Burdach.3 Specific Sugar of Observers. gravity. Butter. Cheese. milk. Water. Extract. m t Brisson, 10409 'g J Boyssou, 38-24 51-26 20-73 886-19 3-45 j° ] Luiscius, 10350 58-12 153-75 41-87 746-25 1 ( John, 54-68 31-25 39-06 875-00 m C Brisson, *| • Boyssou, „«> -\ Luiscius, 10324 24-88 39-40 31-33 900-92 3-45 10280 26-87 89-37 30-62 853-12 | j Schiibler, u 1 John, 24-00 50-47 77-00 848-53 23-43 93-75 39-06 843-75 a [ Brisson, M J Boyssou, 10341 29-95 52-99 20-73 892-85 3-45 ^S j Luiscius, 10360 45-62 91-25 43-75 819-37 o ' John, 11-71 105-45 23-43 849-39 ~ I Brisson, 10364 S ) Boyssou, 0-57 18-43 32-25 938-36 10-36 g ] Luiscius, 10450 0-00 16-25 87-50 896-25 | ( John, 0-00 64-84 35-15 900-00 m t Brisson, 10355 § J Boyssou, 0-92 19-58 39-97 932-60 6-91 •?| J Luiscius, 10230 0-00 33-12 45-00 921-87 •3 ( John, 0-00 11-71 46-87 941-40 1 Medico-Chirurgical Transactions, vol. iii. 2 Chimie Organique, p. 345, Paris, 1833. 1 Physiologie als Erfahrungswissenschaft, 2te Auflage, Leipz., 1833. LACTATION—MILK. 523 From this table, an approximation may be made as to the main dif- ferences between the milk of those animals; but it is not easy to explain the signal discrepancy amongst observers as to the quantity of the different materials in the milk of the same animal. Much, of course, may be dependent upon the state of the milk at the time of the expe- riment; but this can scarcely account for the whole discrepancy. From a great number of experiments, MM. Deyeux and Parmentier1 classed six kinds of milk, which they examined, according to the following table, as regards the relative quantity of the materials they contained. Casein. Butter. Sugar of Milk. Serum. Goat. Sheep. Cow. Sheep. Woman. Cow. Ass. Goat. Mare. Ass. Woman. Mare. Ass. Woman. Mare. Woman. Ass. Mare. Cow. Goat. Sheep. Cow. Goat. Sheep. The following table has been given more recently.2 The constitu- ents of the milk of the human family have been added from Clemm.3 The analysis was made from milk obtained on the twelfth day after delivery. Cow. Goat. Pheep. Ass. Mare. Woman. Water, 861-0 868-0 856-2 907-0 896-3 905-809 Butter, 38-0 33-2 42-0 12-10 traces 33-454 Casein, 68-0 40-2 45-0 16-74 16-2 29-111 Sugar of milk ) and extractive matters, J 29-0 52-8 50-0 ^ , 62-31 87-5 31-537 Fixed salts, 6-1 5-8 6-8 \ 1-939 Messrs. Yernois and A. Becquerel" in 89 observed cases, found the following" constituents in human milk. Maximum. Minimum. 1-04648 1-02561 1-03267 99-998 83-23 88-91 Solid residuum, 14-77 8-33 11-09 Sugar of milk, 5-96 2-52 4-36 Casein and extractive, . 7-09 1-93 3-92 0-67 2-67 0-06 0-14 Human milk has, therefore, more sugar of milk and less cheesy matter than that of the cow; hence it is sweeter; more liquid; less coagulable; and incapable of being made into cheese. It has also albuminous, oleaginous, and saccharine ingredients combined, so as to ' Precis d'Exper., &c. sur les Differentes Especes de Lait, Strasbourg, an vii., 1790. 2 Carpenter, Principles of Physiology, 4th Amer. edit., p. 645, Philad., 1850. 8 Scherer, in Wagner's Handworterbuch der Physiologie, Art. Milch, lOte Lieferung, S. 464, Braunschweig, 1845. For other analyses, see Simon, Animal Chemistry, Syden- ham Soc. edit., ii. 51, London, 1846. 4 Du Lait, chez la Femme, &c, Paris, 1853. A good analysis of this memoir is given by Dr. Day in the Brit, and For. Med.-Chir. Rev. for July, 1855, p. 218. It treats of the milk of healthy nurses ; the influences that may affect it in health; and the changes it experiences in disease. 524 GENERATION. adapt it admirably for the young as an aliment; and of all the secreted fluids it appears to be most nearly allied to blood in its composition.1 M. Bomanet2 has affirmed, that the globules in cow's milk are wholly formed of butter, which exists as a pulp, enveloped in a white, trans- lucent, elastic and resistent pellicle; and that the cyst is broken in churning, by which the butter escapes, and the pellicles floating about separately constitute the white particles that give consistence to but- termilk. When human milk is first drawn it is of a bluer colour than that of the cow. It rather resembles whey, or cow's milk much diluted with water. If allowed to rest, it separates, like the milk of other animals, into cream and milk,—the quantity of the cream being one-fifth to one- third milk. The milky portion, however, appears semitransparent like whey, instead of being white and opaque like that of the cow. During the first days of its remaining at rest, abundance of cream and a little curd are separated, and lactic acid is developed. The specific gravity of human milk was found by Dr. Bees to be 1*0358, and the solid contents 12 per cent. The specific gravity of the cream is 1*021.3 The quantitative analysis of the colostrum, after the investigations of Simon, Chevallier and Henry, Stipriaan Luiscius, Boussingault and Le Bel are thus given by Professor Scherer:—4 Woman. Cow. Ass. Goat. Cow. Casein (Albumen), . Butter, Sugar of milk, Fixed salts, 40-0 50-0 70-0 3-1 (Simon.) 170-7, 26.0 (Chevallier and Henry.) 123-0 275-0 5-0 52-0 43-0 32-0 (BoussingauU and Le Bel.) 151-0 26-0 36-0 3-0 Water, Fixed residue, 828-0 172-0 803-8 196-2 828-4 171-6 641-0 359-0 784-0 216-0 Of the 3*1 of fixed salts unalterable by heat, in Simon's analysis, 1*8 part was insoluble in water. Casein—the nitrogenized constituent of milk—is distinguished from fibrin and albumen by its great solubility, andb>y not coagulating when heated. This is regarded by Liebig5 as " the chief constituent of the mother's blood. To convert casein into blood no foreign substance is required; and in the conversion of the mother's blood into casein no elements of the constituents of the blood have been separated." Examined with the microscope, milk is seen to contain a great num- ber of particles of irregular shape and size, suspended in a somewhat turbid fluid. These vary in size from about the T27ttu to the g^ of an inch, and are called milk globules. They consist of oleaginous mat- ter enclosed in an extremely delicate pellicle of albuminous matter. Other globules of a smaller size are also seen, which exhibit a molecu- lar movement in the fluid. They consist of oily matter not inclosed in an envelope. In the colostrum or first secreted milk, large yellow granulated corpuscles—colostrum corpuscles—are seen, which appear to 1 Dr. G. O. Rees, Art. Milk, Cyclop, of Anat. and Physiol., Nov., 1841. 2 Comptes Rendus, Avril, 1842. 3 Sir Astley Cooper, on the Anatomy of the Breast, Amer. edit., p. 83, Philad., 1845. 4 Op. cit., S. 451. 6 Animal Chemistry, Amer. edit., p. 51, Cambridge, 1842. LACTATION — MILK. 525 be formed of a number of small grains in a state of aggregation. They are chiefly of a fatty nature, being, for the most part, soluble in ether; J Fig. 459. Milk Globules. but traces of an adhesive matter, probably mucus, are then seen hold- ing the particles together. Epithelial scales are also perceptible in milk. The quantity and character of the milk differ according to the quan- tity and character of the food,—a circumstance, which was one of the greatest causes for the belief, that the lymphatics or chyliferous vessels convey to the mammae the materials for the secretion. The milk is, however, situate in this respect like the urine, which varies in quantity and quality according to the amount and kind of solid or liquid food taken. The milk is more abundant, thicker, and less acid, if the female lives on animal food; and possesses the opposite qualities when vege- table diet is used. It is apt, also, to be impregnated with heterogeneous matters, taken up from the digestive canal. The milk and butter of cows indicate unequivocally the character of their pasturage, especially if they have fed on turnip, wild onion, &c. Medicine, given to the mother, may in this way act upon the infant. Serious—almost fatal— narcotism was induced in the infant of a professional friend of the author, by a dose of morphia administered to his wife. It would seem, that occasionally the secretion of the two glands differs. A case has been related in which the milk of the right breast had a distinctly salt taste, whilst that of the opposite breast was of the ordinary sweetness. A difference also is at times observed in the num- ber and size of the globules of the milk obtained from the two breasts. M. Devergie1 has found by examination with the microscope, that the milk of women differs not only in respect to the size of the globules, but to the number of these,—a high or low amount of globules indicating richness or poorness of the milk generally. Of 100 nurses, 17 had the large globuled variety; 22 the small globuled; and 61 the medium size. The quantity of milk secreted is not always in proportion to the bulk of the mammae: a female whose bosom is of middle size often secretes more than one in whom it is much more developed;—the greater size being usually owing to the larger quantity of adipous tissue surround- ing the mammary gland, which tissue is nowise concerned in the func- tion. The ordinary quantity of milk that can be squeezed from either Fig. 460. Colostrum Corpuscles. 1 Mcmoires de l'Acad'hnie Royale de Medecine, torn, x., Paris, 1843. 526 GENERATION. breast at any one time, and which must consequently have been con- tained in its tubes and reservoirs, is about two fluidounces. The secre- tion usually continues until the period when the organs of mastication of the infant have acquired the necessary developement for the diges- tion of solid food; and it generally ceases during the second year. For a great part, or the whole of this time, the catamenia are suspended* and if both the secretions, mammary and menstrual, go on together the former is usually impoverished, and in small quantity. This at least, is the general opinion. Some, however, think, that no general rule can be established on the subject; and that the condition of the child's health ought to be the only guide in regard to weaning, after the recurrence of the catamenia. M. Gendrin would on no account permit a woman to continue nursing after they had returned. The subject has been investigated by M. Kaciborski,1 who laid the results before the Academie Royale de Medecine, of Paris, in May, 1813. His inferences are,—that, contrary to generally received opinion, the milk of nurses who menstruate during suckling does not differ sensibly, in physical, chemical, or microscopic characters, from that of nurses whose catamenia are suspended; that the only difference, which can be de- tected between the two kinds of milk, is, that in most cases the milk of menstruating nurses contains less cream during the menstrual periods than in the intervals, which accounts for the bluish appearance occa- sionally presented by such milk;—and that a nurse should never be rejected merely because she menstruates. Whilst lactation continues, the female is less likely to conceive; hence the importance,—were there not even more weighty reasons,— of the mother's suckling her own child in order to prevent the too rapid succession of children. From observations made at the Man- chester Lying-in Hospital on one hundred and sixty married women, Mr. Koberton2 concludes, that in seven out of eight women, who suckle for as long a period as the working classes in England are in the habit of doing—about fifteen and a half months on the average—there will be an interval of fifteen months between parturition and the commence- ment of the subsequent pregnancy; and that, in a majority of instances, when suckling is prolonged to even nineteen or twenty months, preg- nancy does not take place till after weaning. In a work on the law of population and subsistence, Dr. Loudon3 lays down the theory, that the laws of nature require lactation to be prolonged for three years; and he expresses an opinion, that the antagonism between the uterus and mammae is so great as usually to prevent conception in women who have infants at the breast. The opinion does not agree, however, with the facts arrived at by Dr. Boberton, and it is still more opposed to those of Dr. Laycock,4 who states that 135 married women afforded 209 pregnancies during 766 lactations, or 1 pregnancy in 3*66 lacta- tions, or 27 per cent. The 209 pregnancies occurred in 76 females:— that is, 56 per cent, became pregnant whilst suckling; but in 30 of these, pregnancy occurred only once. If the thirty be deducted, there 1 Dublin Medical Press, Aug. 2d, 1843. 2 Edinb. Med. and Surg. Journal, Jan., 1837. 8 Solution du Probleme de la Population, &c, Paris, 1842; cited by Dr. West, in Brit, and For. Med. Rev., April, 1844, p. 541. * Dublin Medical Press, Oct. 26, If42. F03TAL EXISTENCE—EMBRYOLOGY. 527 remain 46 or 33*9 per cent., or nearly 1 in 3, who became pregnant on more than one occasion whilst suckling; and 19 of these, or 1 in 7 had always—after their first pregnancy—conceived whilst suckling. When menstruation recurs during suckling, it is an evidence that the womb has again the organic activity which befits it for impregna- tion. Vicarious secretion of milk is sometimes—yet rarely—met with. An interesting case of expectoration of a milky fluid has been re- corded by Dr. S. Wier Mitchell,1 of Philadelphia; in which the micro- scope exhibited very perfect milk globules, mingled with compound granular cells, mucous corpuscles, and epithelial scales or lamellae. CHAPTEB II. FffiTAL EXISTENCE.— EMBRYOLOGY. Whilst the uterine alterations, which have been pointed out in the last chapter, are taking place, the ovum is undergoing a succession of changes, and the new being is passing through the different phases of intra-uterine existence. The history of these, in the early period, is extremely obscure, owing to the difficult nature of the investigation; and on many deeply interesting points we are compelled to remain in doubt. It is a subject, which has engaged the attention of physiolo- gists of all ages; but it is chiefly to those of more modern times—as Hunter, Cuvier, Dutrochet, Pander, Bolando, Sir Everard Home and Mr. Bauer, PreVost and Dumas, Von Baer, Kuhlemann, Dollinger, Oken, Purkinje, Bathke, C. F. Wolff, Breschet, Burdach, Beichert, Carus, Krause, Seiler, Bojanus, Meckel, E. H. Weber, Bernhardt, Valentin, Coste, Owen, Sharpey, Velpeau, Flourens, Allen Thomson, T. W. Jones, Bischoff, Schwann and Schleiden, J. Miiller, Pouchet, Wagner and Martin Barry,—the last two of whom received, about the same time, medals for their researches, the former from the Institute of France; the latter from the Boyal Society of London,—that we are indebted for our more accurate and precise information. 1. ANATOMY AND HISTOLOGY OF THE FC3TUS. a. Foetal Developement. As the developement of the mammalia greatly resembles that of birds, the histogeny of the impregnated ovum, at the earliest periods, was, until of late years, chiefly studied in the latter; and there can be no doubt—as Wagner2 has remarked,—that carefully conducted re- searches on the ovum of these animals are much better calculated to throw light on the developement of the human embryo than any amount of necessarily unconnected observations of human ova aborted at an early period; and, in the majority of cases perhaps, morbid. " LTnques- 1 American Journal of the Medical Sciences, July, 1855, p. 83. A similar case ii cited in the Brit, and For. Med. Rev., for Jan., 1840, from Bulletino delle Scienze Mediche, April, 1839. 2 Elements of Physiology, by R. Willis, p. 80, Lond., 1841, 528 FfETAL EXISTENCE. tionably," observes Valentin,1 "the class of birds is the centre around which all observations on developement arrange themselves, and this, not so much on account of any grounds intrinsic to this class, as by reason of extrinsic circumstances, which are completely under our con- trol. In no other class of animals do we possess the same facilities of procuring embryos in the various stages of their progress. Nowhere can we multiply and repeat our inquiries to the same extent as here. It was on this account that Fabricius ab Aquapendente began his in- vestigations with the brooded egg, and that Harvey and Malpighi fol- lowed in the same course. It was on the egg that Wolff made his im- portant discoveries in regard to the formation of the intestinal canal of the blood, of the extremities, and of the kidneys; and it was by the study of the embryo of the common fowl, that Dollinger and his school in our own day, were enabled to give a permanent foundation to the history of developement as a science. The bird must, therefore, and on these grounds, be made the starting point for all future inquiries, the norma and basis to which insulated facts in the developement of mammalia and man must be referred." It has been well remarked, too, by Wagner,2 that whoever would work out a knowledge of the develope- ment of animals generally for himself must begin with the study of the chick, were it only for the reason, that we possess the best descriptive works upon this portion of the subject. The early processes of de- velopement are, indeed, the same in all animals. " The embryos of different animals resemble each other more strongly in proportion as we examine them at an early period. We have already stated, that during almost the whole period of embryonic life, the young fish and the young frog scarcely differ at all; so it is also with the young snake, compared with the embryo bird. The embryo of the crab, again, is scarcely to be distinguished from that of the insect; and if we go still farther back in the history of developement, we come to a period when no appreciable difference whatever is to be discovered between the em- bryos of the various departments. The embryo of the snail, when the germ begins to show itself, is nearly the same as that of a fish or a crab. All that can be predicted at this period is, that the germ, which is un- folding itself, will become an animal: the class and group are not yet indicated."3 The egg of a bird—of a hen, for example—consists of two descrip- tions of parts,—the one comprising those that are but little concerned in the developement of the new being;—the other those that remain after the chick is hatched,—as the shell and the shell membrane which lines it; and those that undergo changes along with the chick, and co- operate in its formation, as the white, the yolk, and the cicatricula macula, tread or gelatinous molecule as it was formerly termed—which includes the germinal vesicle or Purkinjean vesicle, and the germinal or germ sp>ot of later observers. When the ovule quits the ovary, it consists only of the yolk and its investing membrane:—with the germinal vesicle and germinal spot. (See Figs. 425 and 426.) The yolk serves the same purpose for the 1 Handbuch der Entwickelungsgeschichte, Vorrede s. x. 2 Op. cit. 3 Agassiz and Gould, Principles of Zoology, part 1, page 123, Boston, 1848. DEVELOPEMENT OF OVUM. 529 animal as the amylaceous and oily matter in the seed serves for the plant. It is the nutriment on which the embryo subsists, until it is capable of obtaining it in another manner. On this yolk is the cica- tricula, consisting, as has been said, of a nucleated cell, of which the germinal spot is the nucleus,—the germinal vesicle the cell. In its passage through the oviduct, the ovule receives the albumen or white of e°"o-, the purpose of which is to serve as nutriment; for it is gradu- ally taken up as the yolk is exhausted. This is deposited upon the surface of the ovule; and from the bloodvessels of the lining of the oviduct are thrown out the materials that go to Fis- 461. the formation of the shell membrane — membrana testce—as well as of the shell itself. This mem- brane separates into two layers at the larger end of the egg; and, enclosed between them, is the fol- liculus aeris or air cham- ber, containing a bubble of air, and inservient to the respiration of the embryo. The yolk floats within the albumen,and being the lighter of the two tends to rise towards the upper portion; but is retained nearly in the same place by two cords formed of very viscid albumen, which connect the yolk bag with the lining membrane at the two ends of the shell, and are called chalazoz or poles. The ovum of the mamtialia is strikingly analogous to this. When it leaves the ovary, it consists of the yolk or vitellus, contained in its yolk-bag, and of the germinal vesicle and germinal spot. At times, however, the germinal vesicle disappears before the ovum leaves the ovary; but at others not until it has entered the Fallopian tube or oviduct; and it is only in its passage through the tube, that it receives, —by means of nucleated cells, thrown out from the lining membrane,— the chorion, which is thus analogous to the albumen or white, the shell membrane and shell of the bird. In tracing the early developement of the ova of mammiferous ani- mals, difficulty has existed; and hence attention has been chiefly paid to the lower animals, in which there is every reason to believe that similar phenomena occur. Prior to impregnation, the germinal vesicle and germinal spot are visible in the ovum; but after fecundation, the germinal vesicle disappears, and in its place is seen a nucleated cell (Fig. 462, a), which appears to be a new formation. A process of duplication now takes place, which is depicted by Kolliker and Bagge, as seen by them in the ova of certain parasitic worms, in which it pre- sents itself in its least complex form; and, owing to the transparency of the objects, can be the more readily traced. The nucleus of the VOL. II.—34 a. Cicatricula. chalazae. Section of Bird's Egg. 6. Tolk. c. Shell Membrane. e. Chalazae. /. Air-Chamber. d. Attachment of g. Albumen. 530 F03TAL EXISTENCE. first nucleated embryonic cell is divided, and each new nucleus is soon succeeded by two other cells; these by four; and these again by eight, as illustrated in Fig. 462 ; this duplication continuing, and the cells being progressively smaller, until ultimately a large mass of cells results, which assumes the form of the embryo, (h, Fig. 462.) Along with these changes, the yolk is experiencing considerable modi- Fig. 462. JV 35 CD E 3? O H Duplication of Cells. A, b, c, d. Successive stages of the ovum of ascaris dentata, showing duplication of cells, e, f, o, h. Ovum of cucullanus elegans, showing the advance of the process. fication. In some entozoa, as in those described in Fig. 462, the em- bryonic portion is embedded in the interior of the yolk, and as the cells multiply they draw into them the nutrient matter that surrounds them, until the whole yolk is absorbed, and the original yolk-bag is filled with a mulberry-like mass of cells ; but the more common method is for each of the cells formed by the cleaving of the embryonic vesicle to draw around it a certain portion of the yolk as in Fig. 463.1 Fig. 463. Cleaving of the Yolk after Fecundation. A, b, c. Ovum of ascaris nigrovenosa. d and e. That of ascaris acuminata. The same kind of metamorphosis, or cleaving of the yolk, occurs in the mammalia; prior to this, however, certain changes have been ob- served by Bischoff.2 The cells of the membrana granulosa, that are in 1 Baly and Kirkes, Recent Advances in the Physiology of Motion, the Senses, Genera- tion, and Developement, p. 66, London, 1848. 2 Entwickelun^sgeschichte des Hunde-cies, p. 41 ; and Baly and Kirkes, p. 64. TRANSIT OF OVUM THROUGH THE FALLOPIAN TUBE. 531 immediate contact with the ovum, undergo a peculiar change when it is about to leave the ovary—becoming club-shaped, their pointed ex- Fig. 464. ABC Progressive stages in the Segmentation of the Yolk of the Mammalian Ovum. A. Its first division into two halves. B. Subdivision of each half into two. C Further subdivision, producing numerous segments. tremities being attached to the zona pellucida so as to give to the ovum a stellate appearance; but when the ovum has entered the Fallopian Fig. 465. A B Later stage in the Segmentation of the Yolk of the Mammalian Ovum. At A is shown the "mulberry mass" formed by the minute subdivision of the vitelline spheres. At B a further increase has brought its surfaces into contact with the vitelline membrane, against which the spherules are flattened. tube, they lose this shape and become round; and in this form they continue, in the bitch, to invest the ovum throughout the whole tract Fig. 466. Membrana Granulosa of an Ovum from the Ovary. A. An ovarian ovum from a bitch in heat, exhibiting the elongated form and stellate arrangement of the cells of the discus proligerus or membrana granulosa arouad the zona pellucida. B. The same ovum after the removal of most of tho club-shaped cells. 532 F03TAL EXISTENCE. of the Fallopian tube, and are no longer seen when it reaches the uterus; but in the rabbit they disappear at the commencement of the tube, and it is observed that the yolk no longer completely fills the zona pellucida; a clear space being left between them. In its progress through the tube, besides the reception of the chorion as an investing membrane, no change of structure is seen in the ovum, excepting that the zona pellucida is thicker; but Bischoff,1 observed in the rabbit, that regular energetic rotatory movements were executed by the yolk within the zona pellucida, which he ascribed to th.e motions of vibratile cilia on the surface of the yolk. Fig. 467. Ova from the Fallopian Tube and Uterus. a. Ovum of a bitch, from the Fallopian tube, half an inch from its opening into the uterus, showing the zona pellucida with adherent spermatozoids, the yolk divided into its first two segments, and two small granules or vesicles contained with the yolk in the cavity of the zona. b. Ovum of a bitch from the lower extremity of the Fallopian tube: the cells of the tunica granulosa have disappeared: the yolk is divided into four segments, c. Ovum of a bitch from the lower extremity of the Fallopian tube, in a later stage of the division of the yolk. d. An ovum from the uterus ; it is larger, the zona thicker, and the segments of the yolk are very numerous, e. Ovum from the lower extremity of the Fallopian tube burst by compression ; the segments of the yolk have partly escaped, and in each of them a bright spot or vesicle is visible. It is in the second half of the Fallopian tube, that the cleaving of the yolk begins; which is now resolved into a number of smaller sphe- roidal masses, under the same process of duplication that has been witnessed in the entozoa. Each mass contains a transparent vesicle like an oil globule, in which no nucleus has been detected; yet the vesicles would appear to possess plastic powers like the primordial embryonic vesicle from which they descended. At the time when the mammalian ovum has reached the uterus, the cleaving process has ceased; but soon afterwards important changes take place. Each of the globular segments of the yolk becomes sur- rounded by a membrane, which forms it into a cell; and when the peri- pheral cells, which are first formed, are fully developed, they arrange themselves at the surface of the yolk into a kind of membrane, and 1 Muller's Archiv., S. 14, Jahrgansr, 1841 ; and Elements of Physiology, by Baly, p. 1564, Lond., 1838. DEVELOPEMENT OF THE EMBRYO. 533 assume a pentagonal or hexagonal shape from pressing on each other, so as to resemble pavement epithelium. As the globular masses of the interior are gradually formed into cells, they pass to the surface; increase the thickness of the membrane formed by the peripheral layer of cells, whilst the central part of the yolk is filled only with a clear fluid. By this means, the yolk is converted into a kind of secondary vesicle, situated within the zona pellucida, which Bischoff calls the blas- todermic vesicle,—vesicula blastodermica, the blastoderma or germinal membrane, because in it is first observed the germ or earliest trace of the new being. Soon after its formation, the membrane presents, at some point on its surface, an opaque roundish spot, caused by an accu- Fig. 468. Portion of the Germinal Membrane of a Bitch's Ovum, with the Area Pellucida and Rudiments of the Embryo. Magnified ten diameters. A. Germinal membrane, b. Area vasculosa. c. Area pellucida. d. Laminse dorsales. e. Primitive groove, bounded laterally by the pale pellucid substance of which the central nervous system is composed. mulation of cells and nuclei of less transparency than elsewhere; and it is here—in the area germinativa, as it is called—that the embryo first appears. The germinal membrane increases in thickness by the formation of new cells, and is divisible into two layers, which are, at first most distinct at the area germinativa; but the separation soon extends, and affects nearly the whole germinal membrane. The outer layer of these is called the serous layer and also the animal layer, because from it are formed the organs of animal life:—the nervous system, bones, muscles, &c; whilst the latter or inner layer is called the mucous or vegetative layer, because from it are formed the vegetative or nutritive organs. The area germinativa has, at first, a rounded form, which it soon loses, becoming first oval, and then pyriform; and whilst this change is taking place, a clear space—area pellucida—is seen in its centre; this is bounded externally by a more opaque circle, which subsequently 534 FGETAL EXISTENCE. becomes the area or area vasculosa, so called because bloodvessels are there first developed. In the formation of both these areas, the two layers participate. The first appearance of the embryo is seen in the serous layer and in the centre of the area pellucida. It consists of a shallow groove— primitive groove, trace or streak—having on each side two oval masses— laminoz dorsales—the form of which changes with that of the area pel- lucida ; being, at first, oval, then pyriform, and at length shaped like a guitar. At the same time, they become more and more raised, and the tops of the elevations Fig. 469. approach each other, until they ultimately convert the groove into a tube, which is the seat of the future great central organs of the nervous system—the brain and spinal marrow. At the same time, on aline parallel with the primitive groove, a row of cells is seen, which the rudiments of the are future vertebral column;— this is termed the chorda dorsalis. Whilst the dorsal laminae are approaching to close the primitive groove, thickened prolongations of the serous layer are given off from the lower margi n of each. These —called ventral or visceral laminae, laminoz ventrales seu viscerales—at first, proceed on the same plane with the germinal membrane, but Portion of the Germinal Membrane, with Rudiments of the Embryo from the Ovum of a Bitch. The primitive groove, A, is not yet closed, and at its upper or cephalic end presents three dilatations, b, which corre- spond to the three divisions or vesicles of the brain. At its lower extremity the groove presents a lancet-shaped dilata- tion (sinus rhomboidalis) c. The margins of the groove con- sist of clear pellucid nerve-substance. Along the bottom of theV £?raduallv bend doWn- the groove is observed a faint streak, which is probably the i i • l J chorda dorsalis. d. Vertebral plates. Ward and inwards, tOWardS the cavity of the yolk, where they unite, and form the anterior wall of the trunk; and whilst these changes are supervening, an accumulation of cells is taking place between the serous and the mucous layer of the germinal membrane, which arrange themselves into a distinct layer—the vascular—in which the first vessels of the embryo are developed. Such are the phenomena presented by the embryo chick; but, ac- cording to Dr. Martin Barry,1 there does not occur in the mammiferous ovum any such phenomenon as the splitting of a germinal membrane into the " so called serous, vascular, and mucous laminoz. Nor is there any structure entitled to be denominated a germinal membrane; for it 1 Philosophical Transactions for 1838, 1839 and 1840, and Wagner's Elements of Physiology, p. 153 (note), London, 1841. DEVELOPEMENT OF VESSELS. 535 is not a previously existing membrane, which originates the germ; but it is the previously existing germ, which, by means of a hollow process, Fig. 470. Fig. 471. Vascular Area in the Chick thirty-six hours Egg thirty-six hours after Incubation. after Incubation. a. Yolk. b. Fiddle-shaped pellucid area, in the middle of which is the embryo. In the vascular area, c, c, the insula sanguinis or blood islets be- gin to appear. originates the structure having the appearance of a membrane." This we have no doubt is the fact as regards the relation of the germ to the germinal membrane, yet the phenomena may present themselves in the manner above described. When the vascular layer is formed, blood dots or islets—insuloz san- guinis—appear at the circumference of the vascular area, which gra- dually unite so as to form vessels filled with blood, which have a reti- form appearance and circular shape; hence the name circulus venosus and vena seu sinus terminalis given to the figura venosa. The vascular area gradu- ally extends itself over the whole sur- face of the membrane that contains the yolk; as is well seen in the accom- panying figures of the chick at differ- ent stages of incubation. From this network in the area vasculosa, vessels extend into the area pellucida, and join the rudi- mental heart, which has, at first, the form of a long slightly curved tube, prolonged inferiorly into two venous trunks, and superiorly into three or more aortic arches on each side. These arches unite beneath the vertebral co- lumn to form the aorta (Fig. 473). In ■Fig. 472. Egg opened three days after Incubation. 536 FCETAL EXISTENCE. the primitive state of the circulation, thedescending aorta divides intoa right and a left branch (Fig. 474) which pass to the germinal membrane, Fig. 473. Embryo of the Chick at the commencement of the third day, as seen from the abdominal aspect. 4. Prominence of the corpora quadrigemina or optic lobes of the brain. 5. The anterior cerebral mass or hemispheres. 6. The heart. 7. Entrance of the great venous trunks in the atrium cordis or auricle. 8, 9, 10 and 11. The four aortic arches. 12. The descending aorta. 13. The arteries of the germinal membrane. 14. The dorsal lamina, ren- dered slightly wavy by the action of water. 15. The rudiments of the vertebra. Embryo from a Bitch at the 23d or 24th day. Magnified ten diameters. It shows the net-work of bloodvessels in the vas- cular lamina of the germinal membrane and the trunks of the omphalo-mesenteric veins entering the lower part of the S-shaped heart. The first part of the aorta is also seen. Fig. 475. and are termed artericeomphalo-mesentericoz, where they ramify until they reach the circulus venosus, which—as has been seen—surrounds the area vasculosa; from this, the blood is conveyed back by the venoz omphalo-mesentericoz, which issue from the area vasculosa at points corresponding to the anterior and posterior extremities of the embryo (Fig. 474). The sinus terminalis ultimately disap- pears, and the whole yolk-sac becomes covered with bloodvessels. The same plastic material which formed the different bloodvessels is con- cerned in the formation of the blood corpuscles; and the essential use of the bloodvessels themselves is, doubtless, to absorb the nutritious matter of the yolk, and convey it to the embryo for histogenic purposes. At a very early period, the incipient embryo lies, as it does subsequently, with its ventral sur- face on the yolk sac; and soon, in the mammalia, a constriction takes place in the fold of the germinal membrane in Plan of Early Uterine Ovum. Within the external ring, or zona pellucida, are the se- rous lamina, a; the yolk, b; the incipient embryo, c. DEVELOPEMENT OF VESSELS. 537 which the parietes of the abdomen are formed; and from this time the yolk sac becomes the vesicula umbilicalis or umbilical vesicle. The con- stricted portion, which remains open for a time, is the vitelline or omphalo- mesenteric duct, ductus vitellarius, ductus vitello-intestinalis seu apophysis, and the omphalo-mesenteric vessels are still perceptible. Through them, indeed, as at an earlier period, the vitelline matter is conveyed to the embryo. It is affirmed, however, that the vessels are not in im- mediate contact with the yolk,—a layer of nucleated vitelline cells inter- vening, which communicate a yellow colour to the vessels beneath, and hence Haller called those vessels vasa lutea. It would not seem, how- ever, that cell agency is necessary in this case, for adipous matter readily enters the vessels by imbibition. The walls of the umbilical vesicle or yolk sac are formed of the seve- ral layers of the germinal membrane, the mucous and vascular layers of which become much developed; and its vessels—the omphalo-mesen- teric, consisting of an artery and two veins—communicate with the abdomen at the umbilicus by the vitelline duct, which, again, commu- nicates with the cavity of the rudimental intestine of the embryo which had been pinched off from the yolk bag; and it was at one time sup- posed that the nutrient matter of the yolk passed at once through the duct into the rudimental digestive cavity; but it is now generally believed that it is taken up by the vessels in the manner already described. Whilst the umbilical vesicle is experiencing these developements, another vesicle is seen to project gradually from the caudal extremity of the embryo, which is termed the allantois or allantoid vesicle; and has been supposed by some histologists to be an offset, as it were, from Fig. 476. The Amnion in process of formation, by the arching over of the Serous Lamina. a. The chorion. 6. The yolk bag, surrounded by serous and vascular lamin». c. The embryo. d, e, and /. External and internal folds of the serous layer, forming the amnion, g. Incipient allantois. Fig. 477. Diagram representing a Human Ovum in the second month. a, 1. Smooth portion of chorion, a, 2. Villous por- tion of chorion k, k. Elongated villi beginning to col- lect into placenta, b. Yolk sac, or umbilical vesicle. c. Embryo. /. Amnion (inner layer), g. Allantois. h. Outer layer of amnion, coalescing with chorion. the intestinal canal; but, according to Bischoff, it is certainly not so in the mammalia, in which it never attains any great size; but in birds it extends itself around the whole of the yolk sac, between it and the 538 FfETAL EXISTENCE. shell membrane. The figures 476, 477, 478, 479 exhibit it at different stages in the egg of the hen; and in the human ovum. As the allan- tois is developed, its parietes become very vascular, and contain the ramifications of the subsequent umbilical arteries and umbilical vein. Wherever it is met with, it would appear to be a temporary organ of respiration; destined to bring the vessels of the embryo chick in rela- tion with the external air; and in the mammiferous animal to convey the vessels of the embryo to and from the chorion. As the visceral laminse close in the abdominal cavity, the allantois is divided at the umbilicus into two portions; the larger proceeding with the umbilical Fig. 478. Fig. 479. Egg five days after Incubation. Egg ten days after Incubation. vessels to the chorion,—the smaller being retained in the abdomen, and converted into the urinary bladder. The two portions are con- nected by the urachus. But whilst the umbilical vesicle is undergoing its incipient formation, by the constriction of that portion of the yolk sac which is in relation with the future umbilicus of the embryo, an important change is taking place in the serous layer of the germinal membrane, the cephalic, caudal and lateral edges of which rise up in two folds, and extend over the body of the embryo from its abdominal towards its dorsal aspect, where they at length meet, and enclose the embryo in a double envelope, one layer of which—the inner—forms the sac of the amnion; the other lines the internal surface of the chorion. Its mode of developement is seen in Figs. 476, 477 and 480. The amnion is continuous with the integument of the embryo; and the part at which the reflections take place to form it is the umbilicus; this is well illustrated in the marginal figure. When the ovum has reached the interior of the uterus it is surrounded by the chorion, which it received in its passage along the Fallopian tube: the villi or foetal processes on its outer surface come in relation with the enlarged DEVELOPEMENT OF THE EMBRYO. 539 tubular glands of the uterus, and thus the new being derives its early intra-uterine nutriment. Gradually, however, bloodvessels are de- veloped in the villi, which form a junction with those of the allan- tois—the umbilical ves- sels; and in this way an indirect vascular com- munication is established with the uterus, which is concentrated in the part corresponding to the pla- centa. The mode in which this connection is formed will be described when the dependencies of the foetus and its phy- siology are mor.e inti- mately investigated. From the difficulty of appreciating the exact age of any ovum or its contained embryo, it is impracticable to assign precise weights or mea- surements, or, indeed, any special develope- ment to the different periods of intra-uterine existence. The discordance amongst observers is, indeed, extreme; and the following observations can only be re- garded as approximations. The human ovum does not generally reach the uterus until about ten or twelve days after conception, or after its discharge from the ovary. Beference has already been made to the disputed case by Sir Everard Home, in which, on the seventh or eighth day after conception, the future situations of the brain and spinal marrow were said to have been recognizable by a powerful instrument.1 On the thirteenth or fourteenth day, according to M. Maygrier, it is per- ceptible in the uterus, and of about the size of a pea, containing a turbid fluid,in the midst of which an opaque point is suspended. Fig. 481 represents an ovum, which is figured by M. Velpeau, and could not have been more than fourteen days old, unless the midwife, who gave it him, and who was herself the subject of the miscarriage, deceived him; and she appeared to have had no reason for so doing. Good descriptions and representations of the human ovum within the first month from conception are, however, as Wagner2 has remarked, very rare; and many of the accounts apper- 1 Dr. Myddleton Michel, of South Carolina, has desoribed a very early human ovum observed by him; and has referred to various others recorded by different observers, in the American Journal of the Medical Sciences for Oct., 1847, p. 330. 2 Elements of Physiology, translated by R. Willis, p. 161, Lond., 1841, The Umbilical Vesicle, Allantois, &c. a. Represents the dorsal structures of the embryo, b. The am- nion, c. The yolk-sac or umbilical vesicle, c'. The vitelline duct or pedicle of the umbilical vesicle, o. The allantois ; and o'. The Urachus. Fig. 481. :£*•: Ovum fourteen days old. 540 F.03TAL EXISTENCE. Fig. 4S2. tain to diseased ova, or to monstrous or (lis- torted embryos thrown off by abortion. Its weight at this period, has been valued at about a grain;—length one-twelfth of an inch. On the twenty-first day, the embryo appears under the shape of a large ant, according to Aristotle; of a grain of lettuce; a grain of bar- ley, according to Burton; of the malleus of the ear, according to Baudelocque; or is one-tenth of an inch long, according to Pockels. At this period, its different parts have a little more con- sistence ; and those that have afterwards to form bone assume the cartilaginous condition. On the thirtieth day, some feeble signs of the principal organs and of the situation of the upper limbs are visible; length four or five lines. Ovum and Embryo fifteen days old. Fig. 483. Ovum and Embryo twenty-one days old. Fig. 484. Fig. 485. About the forty-fifth day, the shape of the child is determinate; and it now, in the language of some anatomists, ceases to be embryo, and becomes foetus. According to others, it is not entitled to the latter name until after the beginning of the fourth month. The limbs resemble tubercles, or the shoots of vegetables; the body lengthens, but preserves its oval shape,—the head bearing a consi- derable proportion to the rest of the body. The base of the trunk is pointed and elongated. Blackish points, or lines, indicate the presence of the eyes, mouth, and nose; and similar parallel points correspond to the situation of the vertebrae. Length ten lines. In the second month, most of the parts exist. The black points, which represented the eyes, enlarge in every dimension; the eyelids are sketched, and are extremely transparent; the nose begins to stand Foetus at forty-five days. Foetus at two months. F03TAL DEVELOPEMENT. 541 out; the mouth increases, and becomes open; the brain is soft and pulpy, and the heart is largely developed. Prior to this period—very early indeed—sub- stances or bodies are perceptible, which were first described, as existing in the fowl, by Wolff,1 and in the mammalia by Oken,2 and which have been called by the Germans, after their discoverers, Wolffische oder Oken- sche Kdrper ("bodies of Wolff or Oken"). According to J. Miiller, they disappear in man very early, so that but slight remains of them are perceptible after the ninth or tenth week of pregnancy. They cover the region of the kid- neys and renal capsules, which are formed after- wards, and are presumed to be organs of urinary secretion during the first periods of fcetal exist- The fingers and toes are now distinct. ence. In the third month, the eyelids are more de veloped and firmly closed. A small hole is perceptible in the pavilion of the ear. The alae nasi are distinguishable. The lips are very distinct, and approximate, so that the mouth is closed. The genital organs of both sexes undergo an extraordinary increase during this Corpora Wolffiana, with Kid- ney and Testes, from Em- bryo of Birds. 1. Kidney. 2, 2. Ureters. 3. Corpus Wolfflanum. 4. Its ex- cretory duct. 5, 5. Testicles. At the summit are seen the su- pra-renal capsules. month. The penis is long; the scrotum emp- ty, frequently contain- ing a little water. The vulva is apparent, and the clitoris prominent. The brain, although still pulpy, is consider- ably developed, as well as the spinal marrow. The heart beats forci- bly. The lungs are in- significant; the liver very large, but soft and pulpy, and appears to secrete scarcely any bile. The upper and lower limbs are deve- loped. Weight, two and a half ounces; length, three and a half inches. During the fourth month, all the parts Fig. 487. Foetus at three months, in its membranes. 1 Theoria Generationis, Hal., 1759. 2 Oken und Kieser, Beitrage zur Vergleichend. Zoologie, Anatomie und Physiolode H. i. p. 74, Bamburg und Wiirzburg, 1806 ; and Rathke, in Weber's Hildebrandt's Hand- bucb der Anatom., iv. 440. 542 FffiTAL EXISTENCE. acquire great developement and character, except perhaps the head and liver, which increase less in proportion than other parts. The brain and spinal marrow acquire greater consistence; the muscular system which began to be observable in the preceding month is now distinct* and slight, almost imperceptible, movements begin to manifest them- selves. The length of the foetus is, at the end of one hundred and twenty days, five or six inches; the weight, four or five ounces. Durino- the fifth month, the developement of every part goes on; but a dis- tinction is manifest amongst them. The muscular system is well marked, and the movements of the foetus unequivocal. The head is still very large, compared with the rest of the body, and is covered with small silvery hairs. The eyelids are glued together. Length, seven to nine inches; weight, six or eight ounces. If the foetus be born at the end of five months, it may live for a few minutes. In the sixth month, the derma begins to be distinguished from the epidermis. The skin is delicate, smooth, and of a purple colour; especially on the face, lips, ears, palms of the hands and soles of the feet. It seems plaited, owing to the absence of fat in the subcutaneous areolar tissue. The scrotum is small, and of a vivid red hue. The vulva is prominent, and its lips are separated by the projection of the clitoris. The nails appear, and towards the termination of the month are somewhat solid. Should the foetus be born now, it is sufficiently developed to breathe and cry; but it generally dies in a short time. Length, at six months, ten or twelve inches. Weight, under two pounds. During the seventh month all the parts are better proportioned. The head is directed towards the orifice of the uterus, and can be felt by the finger passed into the vagina, but it is still very movable. The eyelids begin to separate, and the membrane, which previously closed the pupil—membrana pupillaris—begins to disappear. The fat is more abundant, so that the form is more rotund. The skin is redder; its sebaceous follicles—which secrete a white, cheesy substance, vernix caseosa, that covers it—are formed; and the testicles are in progress to the scrotum. The vernix has been recently analyzed by Dr. John Davy,1 and found to consist of Epithelium (epidermis) plates,.......13-25 Olein, ........... 5*75 Margarin,...........3*13 Water, ...........77*37 and in the very minute quantity of ashes that remained, there were traces of phosphate of lime and sulphur. It is, consequently, an ex- cretory secretion from the skin. The length, at seven months, is four- teen inches; weight, under three pounds. In the eighth month, the foetus increases proportionably more in breadth than in length. All its parts are firmer and more formed. The nails exist; and the child is now certainly viable or capable of supporting an independent exist- ence. The testicles descend into the scrotum ; the bones of the skull, ribs and limbs are more or less completely ossified. Length, sixteen inches; weight, four pounds and upwards. Medico-Chirurgical Transactions, xxvii. p. 189, Lond., 1S44. FffiTAL DEVELOPEMENT—DIMENSIONS, ETC. 543 At the full period of nine months, the organs have acquired the developement necessary for the continued existence of the infant. Length, eighteen or twenty inches ; weight, six or seven pounds. Ac- cording to Dr. Granville, its length is twenty-two inches; weight from five to eight pounds. Dr. Dewees1 says the result of his experience, in this country, makes the. average weight about seven pounds. He has met with two ascertained cases of fifteen pounds, and many that he believed to be of equal weight. Dr. Moore, of New York, had several cases, where the weight was twelve pounds; and a case oc- curred in that city in 1821, of a foetus, born dead, which weighed sixteen and a half pounds. Dr. Traill2 once weighed a child at the moment of birth; it weighed 14 pounds; Mr. Park, of Liverpool, found one weigh 15 pounds; and a case has been recorded by Mr. J. D. Owens, in which a still-born child measured 24 inches in length, and weighed 17 pounds 12 ounces.3 Dr. Storer,4 of Boston, has pub- lished the following results of observations. Of 30 children, 14 females weighed 112 pounds, or averaged 8 pounds each; and 16 males 145-J pounds, or 8 J pounds each. The largest child seen by Dr. Storer was a male, which weighed 13 pounds; the next in weight was 12J pounds. One weighed 11, one 10}, and two ten pounds each. The average weight of 836 children, recorded by Dr. Metcalf5 of Men- don, Massachusetts, was eight pounds, five ounces, and a fraction. The males—429 in number—weighed eight pounds ten ounces each; the female—407 in number—eight pounds. Dr. Clarke6 gives the absolute and relative weight of 60 of each sex, as observed at the Dublin Hospital:—60 males weighed 442 lbs.; ave- rage 7 lbs., 5 oz., 2 dr. 60 females weighed 404^ lbs.; average 6 lbs., 11 oz., 2 dr. Average difference 9 oz. In the Edinburgh Lying-in Hospital, 50 male and 50 female chil- dren, born during the latter months of 1842, and the earlier part of 1843, were weighed by Dr. Simpson's assistant, Dr. Johnstone.7 50 males weighed 383 lbs., 11 oz., 4 dr.; average 7 lbs., 9 oz., 1 dr. 50 females weighed 342 lbs., 12 oz., 4 dr.; average 6 lbs., 12 oz. Ave- rage difference about 10 oz. The lengths of these were:—50 males, total length, 1020J inches, average 20 inches, 5 lines. 50 females, total length, 990J inches; average 19 inches, 10 lines. Average difference 7 lines, or upwards of half an inch. When there are twins in utero, the weight of each is usually less than in a uniparous case; but their united weight is greater. M. Duges, of Baris, found in 444 twins the average weight to be four pounds, and the extreme weights three, and eight pounds. At times, 1 Compendious System of Midwifery, 8th edit., Philad., 1836. 2 Outlines of a Course of Medical Jurisprudence, 2d edit., p. 16, Edinb., 1840, or American edition with notes by the author of this work, p. 27, Philad.., 1841. 3 London Lancet, Dec. 22, 1838. 4 New England Quarterly Journal of Medicine and Surgery, July, 1842. 5 American Journal of the Medical Sciences, Oct., 1847, p. 314. 6 Philosophical Transactions, 1786. 7 Edinburgh Medical and Surgical Journal, Oct., 1844; see, also, Dr. Simpson's Re- port of the Edinburgh Royal Maternity Hospital, in Monthly Journal and Retrospect of the Medical Sciences, Nov., lb4S, p. 332. 544 F03TAL EXISTENCE. however, they are very large. Dr. P. G. Bertolet, of Oley, Pennsyl- vania,1 describes a twin case in which one child weighed nine pounds and a half,—the other, eleven and a quarter pounds,—the united weights being twenty pounds and three-quarters. The whole of these estimates—as before remarked—give no more than an approximation to the general truth. The facts will be found to vary greatly in individual cases; which accounts for the great dis- cordance in the statements of different observers. This is strongly exemplified in the following table, containing the estimates of the length and weight of the foetus at different periods of intra-uterine ex- istence, as deduced by Dr. Beck2 from various observers, and as given by M. Maygrier3 on his own authority, and by Dr. Granville4 as the averages of minute and accurate observations made by Autenrieth, Sommering, Bichat, Pockels, Carus, &c, confirmed by his own obser- vation of several early ova, and of many foetuses examined in the course of seventeen years' obstetrical practice. It is proper to remark, that the Paris pound, poids de marc, of sixteen ounces, contains 9216 Paris grains; whilst the avoirdupois contains only 8532*5 Paris grains; and that the Paris inch is 1*065977 English inch. Length. Weight. Beck. Maygrier. Granville. Beck. Maygrier. Granville. At 30 days, 2 months, 3 do. 4 do. 5 do. 6 do. 7 do. 8 do. 3 to 5 lines 2 inches 3% do. 5 to 6 do. 7 to 9 do. 9 to 12 do. 12 to 14 do. 16 do. 10 to 12 lines 4 inches 6 do. 8 do. 10 do. 12 do. 14 do. 16 do. 1 inch 3 inches 9 do. 12 do. 17 do. 2 ounces 2 or 3 do. 4 or 5 do. 9 or 10 do. 1 to 2 pounds 2 to 3 do. 3 to 4 do. 9 or 10 grains 5 drachms lyx ounces 7 or 8 do. 16 do. 2 pounds 3 do. 4 do. 20 grains \% onnce 1 pound 2 to 4 pounds 4 to 5 do. The difficulty must necessarily be great in making any accurate estimate during the early periods of fcetal existence; and the changes in the after months are liable to considerable fluctuation. M. Chaus- sier affirms, that after the fifth month, the foetus increases an inch every fifteen days, and M. Maygrier adopts his estimate. The former gentleman has published a table of the dimensions of the foetus at the full period, deduced from an examination of more than fifteen thousand cases. From these we are aided in forming a judgment of the pro- bable age of the foetus in the latter months of utero-gestation;—a point of interest with the medico-legal inquirer. At the full period, the middle of the body corresponds exactly with the umbilicus, or a very little below it; at eight months, it is three-quarters of an inch, or an inch higher. At seven months, it approaches still nearer the sternum; and at six falls exactly at the lower extremity of that bone; hence, if we were to depend upon these admeasurements, should the middle of the body of the foetus be found to fall at the lower extremity of the sternum, we might be justified in concluding, that the foetus is under the seventh month, and consequently not viable or rearable. 1 Medical Examiner, for Aug., 1848, p. 472. 2 Medical Jurisprudence, 6th edit., i. 276, Philad.. 1838. 3 Nouvelles Demonstrations d'Accouchemens, Paris, Ib22-2G. 4 Graphic Illustrations of Abortion, &c, p. xi., Lond., LSJ4. FffiTAL DEVELOPEMENT—DIMENSIONS, ETC. 545 The following are the results of observations made by Dr. A. S. Taylor, Professor of Medical Jurisprudence and Chemistry at Guy's Hospital, and Dr. Geoghegan, Professor of Medical Jurisprudence to the Boyal College of Surgeons in Ireland. Attachment of the Umbilical Cord. A quarter of an inch below the centre. Half an inch Do. Half an inch nearly Do. Half an inch Do. Do. Do. A little below the centre. Exactly at the centre. Do. Do. A little below the centre. Do. Do. Exactly at the centre.1 A striking circumstance connected with the developement of the foetus is the progressive diminution in the proportion of the part of the body above the umbilicus to that below it. At a very early period of foetal life (see Figs. 484 and 485), the cord is attached near the base of the trunk; but the parts beneath become gradually developed, until its insertion ultimately falls about the middle of the body. The following table of the length and weight (French), and central point of the foetus at different ages is given by M. Lepelletier.2 It still farther exhibits the discordance alluded to above. Case. Whole length. 1 18$ 2 20 3 17* . 4 16* . 5 19 6 17 7 18 8 17 9 20f 10 19* . 11 183 Month. Length. Weight. Central point. 1 2 3 4 5 6 7 8 9 5 to 6 lines 18 to 20 lines 2 to 3 inches 5 to 6 inches 7 to 9 inches 9 to 12 inches 12 to 15 inches 15 to 18 inches 16 to 20 inches Extremes. 12 to 15 inches (Millot). 9 to 15 grains 6 to 8 drachms 2 to 3 ounces 10 to 16 ounces 1 to 2 pounds 2 to 3 pounds 3 to 4 pounds 4 to 6 pounds 6 to 8 pounds Extremes. 2 to 16 pounds (Voistel). at the junction of the head and trunk; at the upper part of the sternum. at the upper extremity of the xiphoid car-tilage. at the middle of the xiphoid cartilage. at the lower extremity of the xiphoid car-tilage. several lines helow the xiphoid cartilage. equidistant between the cartilage and the umbilicus. an inch above the umbilicus. at the umbilicus. The position of the foetus in utero, and the cause of such position,at various periods of utero-gestation, have been topics of some interest. In the early weeks, it seems to be merely suspended by the cord; and it has been conceived, that owing to the weight of the head it is the lowest part. It is difficult, however, to admit this as the cause of the position in such an immense majority of cases, or to fancy, that the nice adaptation of the foetal position to the parts through which the 1 See, on all this subject, A. S. Taylor, Medical Jurisprudence, 3d Amer. edit, by Dr. E. Hartshome, p. 286, Philad., 1853. 2 Physiologie Medicale et Philosophique, iv. 451, Paris, 1833. VOL. II.—35 546 FCETAL EXISTENCE. child has to pass is simply dependent upon such a mechanical cause. Gravity can afford us no explanation of the fact, referred to under Parturition, that the face in 12,120 cases of 12,533, has been found turned to the right sacro-iliac synchondrosis, and the occiput to the left acetabulum; and in Fig. 488. the 63 of these cases in which the face was turn- ed forwards, and in the 198 breech presentations, are we to presume, that this was owing to greater weight in these parts that were lowest. Dr. Simp- son1 affirms, that the usual position of the foetus with the head lowest is not as- sumed until about the sixth month of intra-ute- rine life;—that both the assumption and mainte- . nance of this position are vital acts, depending lj upon the vitality of the ' child, and ceasing at death; and that the ce- phalic attitude of the foetus is the one best Full period of utero-Gestation. adapted to the normal shape of the fully de- veloped uterus. The common position, at the full period, is exhibited in the last illustration. The body is bent forward, the chin resting on the chest: the occiput towards the brim of the pelvis; the arms approxi- mated in front, and one or both lying upon the face; the thighs bent upon the abdomen; the knees separated; the legs crossed, and drawn up, and the feet bent upon the anterior surface of the legs; so that the oval, which it thus forms, has been estimated at about ten inches in the long diameter,—the head, at the full period, resting on the neck and even on the mouth of the womb, and the breech correspondfng to the fundus of the organ. It appears then, that from the first moment of a fecundating copu- lation, the minute matters furnished by the sexes, commingled, com- mence the work of developing the embryo. For a short time they find in the ovum the necessary nutriment, and subsequently obtain it from the uterus. The mode in which this action of developement is accom- plished is as mysterious as the essence of generation itself. When the impregnated ovum is first seen it is as an amorphous, gelatiniform mass, in which no distinct organs are perceptible. In a short time, however, the brain and spinal marrow, and bloodvessels, make their appearance; but it has been a topic of controversy which of these is developed first. 1 Monthly Journal of Medical Science, July, 1849. F03TAL DEPENDENCIES. 547 Sir Everard Home,1 from his own observations of the chick in ovo, as well as from the microscopic appearances presented by the ovum in the case of the female who died on the seventh or eighth day after impregnation, decides, that the organs first formed bear a resemblance to brain, and that the heart and arteries are produced in consequence of the formation of nervous centres. Malpighi, Brera, Pander, Tiede- mann, Prevost and Dumas, Velpeau, Kolando, and Schroder van der Kolk,2 also assign the priority to the nervous system. Meckel, how- ever, admits no primitive organizing element, but believes,—properly, we think,—that the first rudiments of the foetus contain the basis of every part. On the other hand, the researches of M. Serres on the mode of developement of the nervous system induce him to be in favour of the earlier appearance of the bloodvessels, and this view seems to be supported by the fact, that if an artery of the brain be wanting, or double, the nervous part to which it is usually distributed is equally wanting, or double. The acephalous foetus has no carotid or vertebral arteries; and the bicephalous or tricephalous have them double or tre- ble. With these views Dr. Granville3 accords, and he lays it down as a law, that the nerves invariably appear after the arteries which they are intended to accompany. A like discordance of ideas exists regarding the precedence in the formation of the heart and the bloodvessels. The blood is clearly formed before the heart. It appears at distinct points, and acquires a motion independently of it. The veins appear to be formed first; and then the heart and arteries. This is the view of perhaps the generality of histologists ; but a distinguished Italian observer—Eolando—assigns the precedency to the arteries. MM. Geoffroy Saint-Hilaire,4 Meckel,5 Serres,6 Tiedemann,7 and others are of opinion, that the developement of the embryo takes place from the sides towards the median line—from the circumference to- wards the centre; but M. Velpeau8 thinks, that the median line is first formed. The spinal marrow is the first portion of the nervous system that appears; and this system, he believes, precedes every other. On all these deeply interesting but most intricate points of organogeny farther researches are demanded. b. Foetal Dependencies. These are the parts of the ovum, that form its parietes, attach it to the uterus, connect it with the foetus, and are inservient to the nutri- tion and developement of the new being. They are generally conceived to consist,—First, of two membranes, according to common belief, which constitute the parietes of the ovule, and are concentric; the outermost, called chorion,—the innermost, filled with a fluid, in which the foetus is placed, and called amnion or amnios. 1 Lect. on Comp. Anat., iii. 292, and 429. 2 Observationes Anatom. Pathol, et Pract. Argum., Amstel., 1826 ; cited in Edinb. Med. and Surg. Journal, for April 1, 1836. 3 Op. cit. 4 Philosophic Anatomique, Paris, 1818-22. 5 Handbuch der Anatomie, Band. i. 8 Recherches d'Anatomie Transcendante, &c, Paris, 1832. 7 Anatomie du Cerveau, traduit par Jourdan, Paris, 1823. 8 Embryoldgie ou Ovologie Humaine, Paris, 1833. 548 FQ3TAL EXISTENCE. By Boer and Granville,1 a third and outer membrane has been admit- ted,—the cortical membrane or cortex ovi. Secondly, of a spongy, vas- cular body, situate without the chorion, covering about one-quarter of the ovule, and connecting it with the uterus—the placenta. Thirdly of a cord of vessels, called the umbilical cord or navel string—extend- ing from the placenta to the foetus, within which are vessels; and lastly, of two vesicles—the umbilical, and allantoid, and some have added a third—the erythroid, which are considered to be concerned in foetal nutrition. As many of these dependencies have already fallen under consideration in certain of their relations, it will not be necessary to say much concerning them here. 1. Chorion.—The chorion—which has received various names—ia the outermost of the membranes of the ovum. It has been already remarked (p. 529) that this envelope is considered to be received by the ovum as it passes along the Fallopian tube. Some, however, maintain that it is present in the ovum before it leaves the ovary; and it is so represented by Gerlach.2 Generally, it is presumed to be formed from an albuminoid secretion of nucleated cells from the lining membrane of the Fallopian tube, and perhaps in addition from the zona pellucida, which disappears at this period. About the twelfth day after conception, according to M. Velpeau,3 it is thick, opaque, resisting, and flocculent at both surfaces. These flocculi, in the part of the ovum that corresponds to the tunica decidua refiexa, aid its adhesion to that membrane; but in the part where the ovum corre- sponds to the uterus they become de- veloped to constitute the placenta. At its inner surface, the chorion corresponds to the amnion. These two membranes are separated, during the earliest period of fcetal existence, by an albuminous fluid; but at the expiration of three months, the liquid disappears, and they are afterwards in contact. By many anatomists, the chorion is conceived to consist originally of two laminae; and by Burdach4 these have been distin- guished by different names; the outer lamina being called exochorim; the in- ner, endochorion. M. Velpeau denies this; and asserts that he has never been able to separate them, even by the aid of pre- vious maceration. As the placenta is formed on the ute- rine side of the chorion, the membrane is reflected over the fcetal surface of that organ, and is continued over the umbili- cal cord as far as the umbilicus of the foetus, where it is confounded Fig. 489. Entire Human Ovum of 8th week, sixteen lines in length (not reckoning the tufts); the surface of the Chorion partly smooth, and partly rendered Bhaggy by the growth of tufts. 1 Graphic Illustrations of Abortion, Lond., 1834. ^ 2 Handbuch der Allgemeinen und Speciellen Gewebelehre des Menschlichen Korpers, 3te Lieferung, S. 341, Mainz, 1849. 3 Embryologie, Paris, 1833. * Physiologie als Erfahrungswissenschaft, ii. 57. FQDTAL DEPENDENCIES—AMNION. 549 with the skin, of which it has consequently appeared to be a depend- ence. As pregnancy advances, the chorion becomes thinner, and less tenacious and dense, so that at the full period it is merely a thin, transparent, colourless membrane, much more delicate than the amnion. Haller, Blumenbach and Velpeau affirm it to be devoid of vessels; but, according to Wrisberg, it receives some from the umbilical trunks of the foetus, and, according to others, from the decidua. M. Dutrochet conceives it to be an extension of the fcetal bladder. Its vascularity, according to Dr. Granville, is proved by its diseases, which are chiefly of an inflammatory character, ending in thickening of its texture; and he affirms, that there is a preparation in the collection of Sir Charles Clarke, which shows the vessels of the chorion as evidently as if they were injected. 2. Amnion.—The amnion—whose mode of formation has been de- scribed before—lines the chorion concentrically. It is filled with a serous fluid, and contains the foetus. In the first days of fcetal exist- ence, it is thin, transparent, easily lacerable, and somewhat resembling the retina. At first, it adheres to the chorion only by a point, which corresponds to the abdomen of the foetus—the other portions of the membranes being separated by the fluid already mentioned, called false liquor amnii. Afterwards, the membranes coalesce, and adhere by very delicate areolar filaments; but the adhesion is feeble, except at the placenta and umbilical cord. In the course of gestation, this membrane becomes thicker and tougher; and, at the full period, is more tenacious than the chorion; elastic, semi-transparent, and of a whitish colour. Like the chorion, it covers the fcetal surface of the placenta, envelopes the umbilical cord, passes to the umbilicus of the foetus, and there commingles with the skin. It has been a question whether the amnion is supplied with blood- vessels. M. Velpeau denies it: Haller and others maintained the affirm- ative. Haller asserts that he saw a branch of the umbilical artery creeping upon it. The fact of the existence of a fluid within it, which is presumed to be secreted by it, would to a certain extent also favour the affirmative. But, admitting that it is supplied with bloodvessels, a difference has existed in regard to the source whence they proceed; and anatomical investigation has not succeeded in dispelling it. Dr. Monro affirms, that on injecting warm water into the umbilical arteries of the foetus, the water oozed from the surface of the amnion. Wris- berg asserts, that he noticed the injection stop between the chorion and amnion; whilst M. Chaussier obtained the same results as Monro, by injecting the vessels of the mother. The amnion contains a serous fluid, the quantity of which is in an inverse ratio to the size of the new'being; so that its weight may be several drachms, when that of the foetus is only a few grains. At first, the liquor amnii,—for so it is called,—is transparent; but, at the full period, it has a milky appearance, owing to flocculi of an albuminous substance held in suspension in it. It has a saline taste, a spermatic smell, and is viscid and glutinous to the touch. Vauquelin and Buniva1 1 Annales de Chimie, torn, xxxiii. ; and Memoires de la Societe Medicale d'Emula- tion, iii. 229. 550 F03TAL EXISTENCE. found it contain, water, 98*8; albumen, chloride of sodium, soda, phos- phate of lime, and lime, 1*2. That of the cow, according to these gen- tlemen, contains amniotic acid; but Prout, Dulong, Labillardiere and Lassaigne were not able to discover it. Dr. Eees analyzed several spe- cimens. He found its specific gravity to be about 1*007 or T008, and its mean composition in two cases at 7* months, as follows: water, 986*8; albumen (traces of fatty matter), 2*8; salts soluble in water 3*7; albumen from albuminate of soda, 1*6; salts soluble in alcohol 3*4; lactic acid, urea, 1*7. Total, 1000. The salts consisted of chlo- ride of sodium, and carbonate of soda, with traces of alkaline sulphate and phosphate. Vogt1 analyzed it at two different periods of preg- nancy, at 31 months and 6 months, and found the constituents to vary as follows:— 3| Months. 6 Months. Water,.......978-45 . . 990-29 Alcoholic extract, consisting of uncertain) o.fiq „„, animal matter and lactate of soda, j Chloride of sodium, ..... 5-95 . . 2-40 Albumen (as residuum), .... 10-79 . . 6-77 Sulphate and phosphate of lime, and loss, . 0.14 . . 0-30 1000- 1000- Specific gravity,......1-0182 . . 1-0092 No inferences can, however, be drawn from these cases as to the proportion of solid matters at different periods of utero-gestation, inas- much as the subject of the first case died of an inflammatory disease; the other of cachexia. Dr. Prout2 found sugar of milk in the liquor amnii of the human female; Berzelius detected fluoric acid in it; Scheele, free oxygen ;3 and Lassaigne,4 in one experiment, a gas re- sembling atmospheric air; in others, carbonic acid and nitrogen. Pro- fessor J. Miiller,5 however, was never able to detect oxygen in it. The chemical history of this substance is, consequently, sufficiently uncer- tain ; nor is its origin placed upon surer grounds;—some physiologists ascribing it to the mother; others to the foetus,—opinions fluctuating, according to the presumed source of the vessels that supply the amnion with arterial blood. It has even been supposed to be the transpiration of the foetus, and its urine. One reply to these views is, that we find it in greater relative pro- portion when the foetus is small. Meckel thinks, that it chiefly pro- ceeds from the mother, but that, about the termination of pregnancy, it is furnished in part by the foetus. The functions, however, to which, as we shall see, it is probably inservient, would almost constrain us to regard it as a secretion from the maternal vessels; and what perhaps favours the idea is the asserted fact, that if a female has been taking rhubarb for some time prior to parturition, the liquor amnii has been found tinged by it.6 It is interesting, also, to recollect, that, in the 1 Muller's Archiv.; cited in Brit, and For. Med. Review, July, 1838, p. 248. 2 Annals of Philosophy, v. 417. 8 Dissert, de Liquoris Amnii Arteriae Asperse Fcetuum Humanorum Natura et Usu, &c, Copenh., 1799. 4 Archiv. General, de Med., ii. 30«. 6 Handbuch der Physiologie, i. 305, Berlin, 1833. 6 Cazeaux, Traite Theorique et Pratique de l'Art des Acoouchements, p. 176, Paris, 1840. F03TAL DEPENDENCIES—PLACENTA. 551 experiments of Dr. Blundell,—which consisted in obliterating the vul vo- merine canal in rabbits, and, when they had recovered from the effects of the injury, putting them to the male,—although impregnation did not take place, the womb, as in extra-uterine pregnancy, was devel- oped, and the waters collected in it. The fluid, consequently, must, in these cases, have been secreted from the interior of the uterus. May not the liquor amnii be secreted in this manner throughout the whole of gestation, and pass through the membranes of .the ovum by simple imbibition? and may not the fluid secretions of the foetus, which are discharged into the liquor amnii, traverse the membranes, and enter the system of the mother in the same way ? The quantity of the liquor amnii varies in different individuals, and in the same individual at different pregnancies, from four fluidounces to as many pints. Occasionally, it is to such an amount as to throw obscurity even over the very fact of pregnancy. An instance of the kind, strongly elucidating the necessity of the most careful attention on the part of the practitioner, occurred in the practice of a respectable London practitioner,—a friend of the author. The abdomen of a lady had been for some time enlarging by what was supposed to be abdomi- nal dropsy; fluctuation was evident, yet the case was equivocal. A distinguished accoucheur, and a surgeon of the highest eminence, were called in consultation, and after examination the latter declared, that " it was an Augean stable, which nothing but the trocar could clear out." As the lady, however, was even then complaining of intermit- tent pain, it was deemed prudent to make an examination per vaginam. The os uteri was found dilated and dilating; and in a few hours after this formidable decision, she was delivered of a healthy child, the gush of liquor amnii being enormous. After its discharge, she was reduced to the natural size, and the dropsy, of course, disappeared. 3. Cortical membrane or cortex ovi. This is, according to Boer and Granville,1 the membrane that is usually regarded as a uterine produc- tion, and denominated decidua refiexa. In the view of Boer, it sur- rounds the ovule when it descends into the uterus, and envelopes the shaggy chorion. This membrane is destined to be absorbed during the first months of utero-gestation, so as to expose the next membrane to the contact of the decidua; with which a connexion takes place in the part where the placenta is to be formed. In that part, Boer and Granville consider, that the cortex ovi is never altogether obliterated, but only made thinner; and in process of time it is converted into a mere pellicle or envelope, which not only serves to divide the filiform vessels of the chorion, into groups or cotyledons, in order to form the placenta, but also covers those cotyledons. This Dr. Granville calls membrana propria. The cortical membrane is not admitted by physio- logists. 4. Placenta.—This is a soft, spongy, vascular body, formed at the surface of the chorion, adherent to the uterus, and connected with the foetus by the umbilical cord. It is not in existence during the early period of the embryo state; but its rudimental formation commences, perhaps, with the arrival of the embryo in the uterus. In the opinion 1 Graphic Illustrations of Abortion, part, iv., Lond., 1835. 552 F03TAL EXISTENCE. of some, the flocculi, which are at first spread uniformly over the whole external surface of the chorion, gradually congregate from all parts of the surface into one, uniting with vessels proceeding from the uterus and traversing the decidua, to form the placenta;—the decidua disap- pearing from the uterine surface of the placenta about the middle of pregnancy, so that the latter comes into immediate contact with the uterus. In the opinion of others, it is formed by the separation of the layers of the chorion, and by the developement of the different vessels that creep between them. M. Velpeau1 maintains, that the placenta forms only at the part of the ovule which is not covered by the true decidua, and which is immediately in contact with the uterus; and that it results from the developement of the granulations which cover this part of the chorion;—these granulations or villi, according to him, being gangliform organs containing the rudiments of the placental ves- sels. Others, again, regard it as formed by the growth of the vessels of the uterus into the decidua serotina. An accurate histologist, Pro- fessor Goodsir,2 has investigated this subject, and the following is his account of the incipient formation of the placenta from the elements supplied by the vascular villi of the chorion on the one hand, and the decidua on the other. The vessels of the decidua enlarge, and assume the appearance of sinuses, encroaching on the space formerly occupied by the cellular decidua, in the midst of which the villi of the chorion are embedded. The increase in the caliber of the decidual capillaries proceeds to such an extent, that the villi are finally completely bound up and covered by the membrane that constitutes the walls of the ves- sels,—this membrane filling the contour of all the villi, and even pass- ing to a certain extent over the branches and stems of the tufts. Between this membrane or wall of the enlarged decidual vessels, and the internal membrane of the villi, there still remains a layer of the cells of the decidua. From this up to the full period, all that portion of decidua in connexion with the group of enlarged capillaries and vascular tufts of the chorion, and which, according to Mr. Goodsir, may be now called a placenta, is divided into two portions. The first por- tion of the decidua in connexion with the placenta, or forming a part of it, is situate between that organ and the wall of the uterus. "This," says Mr. Goodsir, "is the only portion of the placental decidua, with which anatomists have been hitherto acquainted, and I shall name it the parietal portion. It has a gelatinous appearance, and consists of rounded or oval cells. Two sets of vessels pass into it from the uterus. The first set includes vessels of large size, which pass through it for the purpose of supplying the placenta with maternal blood for the use of the foetus. These may be named the maternal functional vessels of the placenta. The second set are capillary vessels, and pass into this portion of the decidua for the purpose of nourishing it. They are the nutritive vessels of the placenta." The mode in which the placenta is attached to the uterus has been an interesting question with physiologists; and it has been revived, of 1 Embryologie ou Ovologie Humaine, p. 63. 2 Anatomical and Pathological Considerations, p. 60, Edinb., 1845. FQHTAL DEPENDENCIES—PLACENTA. 553 late years, by Messrs. Lee,1 Eadford,2 and others. A common opinion has been, that the large venous canals of the uterus are uninterruptedly continuous with those of the placenta. Wharton and Eeuss,3 and a number of others, conceive, that at an early period of pregnancy the part of the uterus in contact with the ovum becomes fungous or spongy, and that the fungosities, which constitute the uterine placenta, com- mingle and unite with those of the chorion so intimately, that lacera- tion necessarily occurs when the placenta is extruded ; and M. Dubois goes so far as to consider milk fever as a true traumatic disease, pro- duced by such rupture. The opinion of Messrs. Lee, Eadford, Vel- peau, and others is, that the maternal vessels do not terminate in the placenta; but that apertures—portions scooped out, as it were,—exist in the parietes of those vessels, which are closed up, according to the two first gentlemen, by the true decidua;—according to M. Velpeau, by a membranule or anorganic pellicle, which he conceives to be thrown out on the fungous surface of the placenta,—or by some valvular arrangement, the nature of which has not been discovered; but these apertures have no connexion, in his opinion, with any vascular orifice either in the membrane or placenta. The mode, therefore, in which these authors consider the placenta to be attached to the uterus is, so far as it goes, somewhat unfavourable to the idea generally entertained, that the maternal vessels pour their fluid into the maternal side of the placenta, whence it is taken up by the radicles of the umbilical vein. Whatever blood is exhaled must necessarily pass through the decidua, according to Messrs. Lee and Eadford; or through the pellicle, accord- ing to M. Velpeau. Subsequently Dr. Lee4 somewhat modified his views, and expressed a belief, that the circulation in the human ovum, in the third month of gestation, is carried on in the following manner:— The maternal blood is conveyed by the arteries of the uterine decidua into the interstices of the placenta and villi of the chorion. The blood, which has circulated in the placenta, is returned into the veins of the uterus by the oblique openings in the decidua covering the placenta. The blood which has circulated between the villosities of the chorion, passes through the opening in the decidua refiexa into the cavity between the two deciduous membranes, whence it is taken up by the numerous apertures and canals that exist, according to him, in the uterine decidua; and so passes into the veins of the uterus. Biancinf5 maintains, that a number of flexuous vessels connect the uterus directly with the placenta, which are developed immediately after the period of conception. These utero-placental vessels, he says, are not prolon- gations of the uterine vessels, but a new production. The late Dr. John Eeidfi carefully examined this point of anatomy. On cautiously separating the adhering surfaces of the uterus and pla- 1 Philosoph. Trans, for 1822; and Remarks on.the Pathology and Treatment of some of the most important Diseases of Women, Lond., 1833. 2 On the Structure of the Human Placenta, Manchester, 1837. 3 Novae qusedam Observationes circa Structuram Vasor. in Placent. Human, et pecu- liarem hujus cum Utero Nexum, Tubing., 1784. * London Med. Gazette, Dec, 1838. 6 Sul Commercio Sanguigno tra la Madre e il Feto, Pisa, 1833. s Edinburgh Med. and Surg. Journal, Jan., 1841, p. 4. 554 FCETAL EXISTENCE. Fig. 490. centa under water, he satisfied himself, but not without considerable difficulty, of the existence of theutero-placentalvesselsdescribedby theHuntors. After a portion of the placenta had been detached in this manner, Dr. Eeid's attention was attracted towards a number of rounded bands passing be- tween the uterine surface of the placenta and the inner surface of the uterus, several of which could Fig. 491. The Extremity of a Villus magnified 200 diameters. The loop, 1, is filled with empty'; 3 is the margin' of Portion of the ultimate ramifications of the Umbilical vessels, form- the pellucid villus. ing the Foetal Villi of the Placenta. be drawn out in the form of tufts from the uterine sinuses. On slitting up some of the sinuses with the scissors, the tufts could be seen rami- fying in their interior. These were ascertained to be prolongations of the fcetal placental vessels, and to protrude into certain of the uterine sinuses, and in those placed next the inner surface of the uterus only. These tufts were surrounded externally by a soft tube, similar to the soft wall of the utero-placental vessels, which passed between the mar- gin of the open mouths of the uterine sinuses and the edges of the ori- fices in the decidua through which the tufts protruded into the sinuses. On examining the tufts, as they lay in the sinuses, it was evident, that Fig. 492. Diagram of the structure of the Placenta, Showing a, the substance of the uterus, b. The cavity of a sinus, e. Curling arteries. dual lining of the uterus, e, e. The foetal tufts dipping down into this. d, d. The deci- though they were so far loose, and could be floated about, yet they were bound down firmly at various points by reflections of the inner coat of the venous system of the mother upon their outer surface. Dr. Eeid farther satisfied himself, that the interior of the placenta is composed of numerous trunks and branches, each including an artery and an accompanying vein, every one of which, he believes, is closely en- F(ETAL DEPENDENCIES—PLACENTA. 555 sheathed in prolongations of the inner coat of the vascular system of the mother, or at least in a membrane coutinuous with it. According to this idea of the structure of the placenta, the inner coat of the vascular system of the mother is prolonged over each indivi- dual tuft, so that when the blood of the mother flows into the placenta through the curling arteries of the uterus, it passes into a large sac formed by the inner coat of the vascular system of the mother, which is intersected in many thousands of different directions by the placental tufts projecting into it like fringes, and pushing its thin wall be- fore them, in the form of sheaths, that closely envelope the trunk and each in- dividual branch composing these tufts. Fig. 494. Connexion between the Maternal and Foetal Vessels. a. Curling artery, b. Uterine vein. c. Placenta, d. Placental tufts with inner coat of vascular system of the mother enveloping them. Portion of one of the Foetal Villi, about to form part of the Placenta, highly magnified. a, a. Its cellular covering, b, b, b. Its looped vessels, c, c. Its basis of connective tissue. From this sac, the maternal blood is returned by the utero-placental veins without having been extravasated, or without having left the maternal system of vessels. Into this sac in the placenta containing the blood of the mother, the tufts of the placenta hang like the branchial vessels of certain aquatic animals, to which they have a marked ana- logy. This sac is protected and strengthened on the fcetal surface of the placenta by the chorion, on the uterine surface by the decidua vera, and on the edges or margin by the decidua refiexa. In this view, the foetal and maternal portions are everywhere inti- mately intermixed with tufts of minute placental vessels, their blunt extremities being found lying immediately under the chorion covering its foetal surface, as well as towards its uterine surface. The discovery of the prolongations of the fcetal placental vessels into some of the uterine sinuses, Dr. Eeid thinks, is principally valuable, as it presents us with a kind of miniature representation of the whole structure of the placenta; and the reason why the placental tufts are not percep- tible on the uterine surface of the placenta expelled in an accouchement is, that they are so strongly bound down by the reflection of the inner coat of the uterine sinuses that they are torn across. Professors Ali- son, Allen Thomson, and J. Y. Simpson inspected the preparations of Dr. Eeid, and expressed themselves satisfied, that the placental tufts were 556 FCETAL EXISTENCE. prolonged into the uterine sinuses, and that the inner coat of the veins was prolonged upon them. Dr. Sharpey, too, confirms the views of Dr. Fig. 495. Section of a portion of a fully-formed Placenta, with the part of the Uterus to which it is attached. a. Umbilical cord. 6, 6. Section of uterus, showing the venous sinuses, c, c, c. Branches of the um- bilical vessels, d, d. Curling arteries of the uterus. Eeid from his own observation of impregnated uteri; and Dr. Churchill1 states, that in a visit to Edinburgh, Dr. Eeid showed him one of the portions of uterus and placenta on which his investigations were made, and there was no difficulty in demonstrating the tufts dipping into the uterine sinuses. " No doubt," he adds, " farther observations are necessary for the perfect elucidation of the subject; but I certainly think, that as far as our knowledge extends, it is in favour of the opin- ion adopted by Dr. Eeid and the later physiologists." A somewhat similar view to that of Dr. Eeid is entertained by Prof. E. H. Weber.3 The fcetal placental tufts, when injected, form beautiful prepara- tions. Since Dr. Eeid's observations were made, Professor Goodsir3 has dis- covered on the fcetal tufts villi like those of the intestinal canal, and internal cells on the tufts, which he considers to be precisely analogous to those of the intestinal villi, described in the first volume of this work. "Within the internal membrane," he remarks,-"and on the external surface of the umbilical capillaries, are cells, which I have named the internal cells of the tuft. When the vessels are engorged, these cells 1851. The Theory and Practice of Midwifery, Amer. edit., by Dr. Condie, p. 119, Philad., 2 Hildebrandt, Handbuch der Anatomie des Menschen, iv. 496, Braunschweig, 1832. 3 Anatomical and Pathological Observations, Edinburgh, 1845. FffiTAL DEPENDENCIES—PLACENTA. 557 are seen with difficulty. When the vessels are moderately distended, and the internal membrane separated from the external cells by moderate pressure, the cells now under consider- ation come into view. They are best seen in the spaces left between the internal membrane and the retiring angles formed by the coils or loops of the vessels, and in the vacant spaces formed by these loops. These cells are egg-shaped, highly transparent, and are defined by the instrument with difficulty; but their nuclei are easily perceived. They appear to be filled with a highly transparent refractive matter. This system of cells fills the whole spaTJe that intervenes between the internal membrane of the villus 'and the vessels, and gives to this part of the organ a mottled appearance." The function of the external cells of the placental villi is, in Mr. Goodsir's view, to separate from the blood of the mother the matter destined for the blood of the foetus. " They are, therefore, secreting cells, and are the remains of the secret- ing mucous membrane of the uterus." The cells within the placental villi—the " internal cells" referred to above—belong to the system of the foetus. They are the cells of the villi of the chorion, and their function is to absorb "the matter secreted by the agency of the exter- nal cells of the villi." The placenta, consequently, in Mr. Goodsir's view, performs not only the function of a lung, but that of an intes- tinal tube. In whatsoever manner primarily formed, the placenta is distinguish- able in the second month, at the termination of which it covers two- thirds, or at least, one-half of the ovum: after this, it increases in size, but far less rapidly than the ovum. Prior to the full term, however, it is said to be less heavy, more dense, and less vascular, owing—it has been conceived—to several of the vessels that formed it having become obliterated and converted into hard fibrous filaments; a change, which has been regarded as a sign of maturity in the foetus, and a prelude to its birth. At the full period, its extent has been estimated at about one- fourth of that of the ovum; its diameter from six to nine inches; cir- cumference twenty-four inches; thickness from an inch to an inch and a half at the centre, but less than this at the circumference; and its weight, with the umbilical cord and membranes, at from twelve to twenty ounces. All this is subject, ho"wever, to much variation. Of 825 observed cases in the Edinburgh Eoyal Maternity Hospital,1 the average weight was lb. 1, oz. 4, dr. 14 [?] Its shape is circular, and the cord is usually inserted into its centre. It may be attached to any part of the uterus, but is usually found towards the fundus. Of its two surfaces, that which corresponds to the uterus is divided into irregularly rounded lobes or 1 Monthly Journal and Retrospect of the Medical Sciences, Nov., 1848, p. 332. Fig. 496. Extremity of a Placental Villus. a. External membrane of the villus, continu- ous with the lining membrane of the vascular system of the mother. 6. External cells of the villus, belonging to the placental decidua. c, c. Germinal centres of external cells, d. The space between the maternal and foetal portions of the villus, e. The internal membran#of the villus, continuous with the external membrane of the chorion. /. The internal cells of the villus, belonging to the chorion, g. The loop of umbilical vessels. 558 FCETAL EXISTENCE. cotyledons, and is covered by a soft and delicate areolo-vascular mem- brane, which, by many, is considered to be decidua vera. Wrisbero-' Fig. 497. Fig. 498. Uterine Surface of the Placenta. Foetal Surface of the Placenta. Lobstein,2 and Desormeaux,3 however, who consider, that the decidua disappears from behind the placenta about the fourth or fifth month, regard it as a new membrane; and Bojanus, believing it to be produced at a later period than the decidua vera, gives it the name of decidua serotina* (See Fig. 443, page 489 of this volume.) M. Breschet, again, affirms, that two laminae—decidua vera and decidua refiexa—are found, intervening between the uterus and placenta,5 whilst M. Velpeau maintains that the true decidua never exists there! The fcetal or umbilical surface is smooth ; polished; covered by chorion and amnion, and exhibits the distribution of the umbilical vessels, and the mode in which the cord is attached to the organ. The following are the chief anatomical constituents of the placenta, as usually described by anatomists. First. Bloodvessels from two sources,—the mother and foetus. The former proceed from the uterus, and consist of arteries and veins, the arteries of small size but of consi- derable number. The vessels, which proceed from the foetus, are those contained in the umbilical cord—the umbilical vein, and umbilical arteries. These vessels, after having penetrated the foetal surface of the placenta, divide in the substance of the organ, so that each lobe and perhaps each ultimate tuft has an arterial and a venous branch, which ramify in it, but do not anastomose with the vessels of other lobes. Secondly. White filaments, which are numerous in proportion to the advancement of pregnancy, and seem to be obliterated vessels. Thirdly. Intermediate areolar tissue, serving to unite the vessels together, and which has been regarded, by some anatomists, as an extension of the decidua accompanying those vessels. Lastly. A quantity of blood con- 1 Observ. Anat. Obstetric, de Structura Ovi et Secundinar. Human., &c, Gotting., 1783. 2 Essai sur la Nutrition du Fetus, Strasbourg, 1802. 3 Art. 03uf Humain, in Diet, de Medecine. 4 Isis, von Oken, fiir 1821. s Memoir, de l'Academ. Royal, de Medec, torn, ii., Paris, 1833. FCETAL DEPENDENCIES—PLACENTA. 559 tained in the ultimate maternal and fcetal vessels. In addition to these constituents, lymphatic vessels have been presumed to exist in it. Fohmann1 affirms, that in addition to the bloodvessels, the umbilical cord consists of a plexus of absorbents, which may be readily injected with mercury. This has been done, also, by Dr. Montgomery, of Dub- lin. The lymphatics of the cord communicate with a net-work of lym- phatics, seated between the placenta and amnion, the termination of which Fohmann could not detect, but, he thinks, they pass to the ute- rine surface of the placenta. These proceed to the umbilicus of the child, and chiefly unite with the subcutaneous lymphatics of the abdo- minal parietes; follow the superficial veins; pass under the crural arches; ramify on the iliac glands; and terminate in the thoracic duct. Lobstein and Meckel, however, were never able to detect lymphatics in the cord. Chaussier and Eibes,2 and Mr. Csesar Hawkins3 describe nerves in the placenta which they refer to the great sympathetic of the foetus. The uterine and fcetal portions of the placenta are generally described as quite distinct from each other during the first two months of fcetal life; but afterwards as constituting one mass. The uterine vessels remain distinct from the fcetal—the uterine arteries and veins commu- nicating freely with each other, as well as the foetal arteries and veins; but no direct communication exists between the maternal and fcetal vessels. Until of late, almost every obstetrical anatomist adopted the division of the placenta into two parts, constituting—as it were—two distinct placentae,—the one maternal, the other fcetal. Messrs. Lee, Radford, and others, however, contested this point, and affirmed, with M. Velpeau, that the human placenta is entirely foetal. If, indeed, the idea of M. Velpeau were true, that a membrane, or as he calls it,— "membranule," exists between the placenta and the uterus, it would destroy the idea of any direct adhesion between the placenta and uterus, and make the placenta wholly fcetal. Yet the point—as we have seen —is still contested,—by those especially, who consider that both the maternal and fcetal vessels ramify in the placenta, a view now embraced by the best histologists. It is generally supposed, that the placenta is most frequently attached to the right side of the uterus, but Nagele4 found the opposite to be the fact in his examinations. In six hundred cases, which he carefully auscultated, it was met with in two hundred and thirty-eight cases on the left side, and in one hundred and forty-one on the right. 5. Umbilical cord.—From the fcetal surface of the placenta a cord of vessels passes, which enters the umbilicus of the foetus, and has hence received the names Funis, F. umbilicus, umbilical cord, and navel string. It forms the medium of communication between the foetus and placenta. During the first month—Pockels5 says the first three weeks—of fcetal 1 Sur les Vaisseaux Absorbans du Placenta, &c, Liege, 1832 ; and Amer. Journ., May, 1835, p. 174. 2 Journal Universel des Sciences Medicales, i. 233. 3 Sir E. Home, Lect. on Comp. Anat., v. 185, Lond., Is28. 4 Die Geburtsniilniche Auscultation, Mainz, 1838; cited in Brit, and For. Med. Rev Oct., 1839, p. 371. 5 Neue Beitrage zur Entwickelungsgeschichte des Menschlichen Embryo, in Isis.von Oken, 1B25. 560 FCETAL EXISTENCE. existence, the cord is not perceptible; the embryo appearing to be in contact, by the anterior part of its body, with the membranes of the ovum. Such, at least, is the description of most anatomists; but M. Velpeau1 says it is erroneous. The youngest embryo that he dissected had a cord. At from a fortnight to three weeks old, its length is three or four lines; and he thinks his examinations lead him to infer, that at every period of fcetal developement, its length is nearly equal to that of the body, if it does not exceed it a little. In an embryo a month old, M. Beclard2 observed vessels creeping, for a certain space, between the membranes of the ovum, from the ab- domen df the foetus to a part of the chorion, where the rudiments of the future placenta were visible. During the fifth week, the cord ia straight, short, and very large, owing to its containing a portion of intestinal canal. It presents, also, three or four dilatations, separated by as many contracted Fig- 499. portions or necks; but these gradually disap- pear; the cord length- ens, and becomes small- er, and occasionally it' is twisted, knotted, and tuberculatedinastrange manner. (Fig. 499.) After the fifth week it contains — besides the duct of the umbilical vesicle—the omphalo- Knotted Umbilical Cord. mesenteric vessels, and a portion of the urachus or of the allantoid vesicle and intestines. At about two months, the digestive canal enters the abdomen: the urachus, the vitelline canal, and the vessels become obliterated, so that, at three months, as at the full period, the cord is composed of three vessels,—the umbilical vein, and two arteries of the same name,—of a peculiar jelly-like substance, and is surrounded, as we have seen, by the amnion and chorion. These are united by an areolar tissue, containing the jelly of the cord, or jelly of Wharton, a thick albuminous secretion, which bears some resem- blance to jelly, and the quantity of which is very variable. In the foetus, the areolar tissue is continuous with the sub-peritoneal areolar tissue; and in the placenta, it is considered to accompany the ramifi- cations of the vessels. The length of the cord varies, at the full period, from eight inches to fifty-four. The most common length is eighteen inches. It has been already remarked, that Chaussier, Eibes, and Hawkins have traced branches of the great sympathetic of the foetus as far as the placenta; and the same has been done by Durr,3 Eieck,4 and others. 6. Umbilical vesicle.—This vesicle, called also vesicula alba and intes- 1 Embryologie ou Ovologie Humaine, Paris, 1833. z Embryologie ou Essai Anatomique sur le Fetus Humain, Paris, 1821. 3 Dissert. Sistens Funicul. Umbilic. Nervis Carere, Tubing., Ibl5. 4 Utram Funiculus Umbilicalis Nervis polleat aut careat., Tubing., 1816. FCETAL DEPENDENCIES—UMBILICAL VESICLE. 561 tinal vesicle, appears to have been first carefully observed by Albinus.1 Dr. Granville,2 however, ascribes its discovery to Bojanus,3 whilst others have assigned it to Diemerbroeck.4 It was unknown to the ancients; and, amongst the moderns, is not universally admitted to be a physio- logical condition. Osiander and Dollinger class it amongst imaginary organs; and M. Velpeau remarks, that out of about two hundred vesicles, which he had examined, in foetuses under three months of developement, he had met with only thirty in which the umbilical vesicle was in a state that could be .called natural. Under such cir- cumstances, it is not easy to understand how he distinguished the natural from the morbid condition. If the existence of the vesicle be a part of the natural process, the majority of vesicles ought to be healthy or natural; yet he pronounces the thirty in the two hundred to be alone properly formed; and, of consequence, one hundred and seventy to be morbid or unnatural. This vesicle is described as a small pyriform, round or spheroidal sac; which, about the fifteenth or twen- tieth day after fecundation, is of the size of a common pea. It proba- bly acquires its greatest dimensions in the course of the third or fourth , week. After a month, M. Velpeau always found it smaller. About the fifth, sixth, or seventh week, it is about the size of a coriander seed. After this, it becomes shrivelled, and disappears insensibly. It seems to be situate between the chorion and amnion, and is commonly adherent either to the outer surface of the amnion, or the inner surface of the chorion; but, at times, is situate loosely between them. It is seen in Figs. 443, 476, 477, and 480. The characters of the vitelline pedicle, as M. Velpeau terms it, which attaches the vesicle to the embryo, vary according to the stage of gesta- tion. At the end of the first month, it is not less than two, nor more than six lines long, and about a quarter of a line broad. Where it joins the vesicle, it experiences an infundibuliform expansion. Its continuity with the intestinal canal appears to be undoubted.5 Up to twenty or thirty days of embryonic life, the pedicle is hollow, and, in two subjects, M. Velpeau was able to press the contained fluid from the vesicle into the abdomen, without lacerating any part. Generally,. the canal does not exist longer than the expiration of the fifth week, and the obliteration appears to proceed from the umbilicus towards the vesicle. The parietes of the vitelline pouch—as M. Velpeau calls it, from its analogy to the vitelline or yolk-bag of the chick—are strong and resisting; somewhat thick, and difficult to tear. As the umbilical vesicle of brutes has been admitted to be continu- ous with the intestinal canal, anatomists have assigned it and its pedicle three coats. Such is the view of M. Dutrochet. M. Velpeau has not been able to detect these in the human foetus. He admits, however, a serous surface, and a mucous surface. The vesicle—as elsewhere remarked6—is supplied with arteries and veins, generally termed omphalo-mesenteric or omphalo-meseraic, but, by M. Velpeau, vitello- 1 Annotat. Academic, lib. i. p. 74. 2 Graphic Illustrations of Abortion, p. xii., Lond., 1834. 3 Meckel's Archiv., iv. S. 34. 4 Opera, p. 304, Ultraject., 1672. 6 Purkinje, art. Ei, in. op. cit., x. 157. 6 Page 536. VOL. II.—36 562 FCETAL EXISTENCE. mesenteric, or, simply, vitelline. The common belief is, that thev com- municate with the superior mesenteric artery and vein; but M. Vel- peau says he has remarked, that they inosculate with one of the branches of the second or third order of those great vessels (canai/x),— with those, in particular, that are distributed to the CEecum. The fluid contained in the vesicle, the vitelline fluid, was examined in a favour- able case for the purpose by M. Velpeau, who found it of a pale yellow colour ; opaque; of the consistence of a thickish emulsion ; different in every respect from serosity, to which Albinus, Boerhaave,1 Wris- berg2 and Lobstein3 compared it, and from every other fluid in the organism; and he regards it as a nutritive substance—a sort of oil—in a great measure resembling that which constitutes the vitelline fluid of the chick in ovo. 7. Allantoid vesicle or allantois.—This vesiple—called also membrana farciminalis and membrana intestinalis—has been alternately admitted and denied to be a part of the appendages of the human foetus, from the earliest periods until the present day. It has been seen by Em- mert, Meckel, Pockels, Velpeau, Von Baer, Burdach, and others; is situate between the chorion and amnion, and communicates, in animals, as before shown—with the urinary bladder by a duct called urachus. It has been observed in the dog, sheep, cow, in saurian and ophidian reptiles, birds, &c. M. Velpeau4 was never able to detect any commu- nication with the bladder in the human subject, and he is compelled to have recourse to analogy to infer, that any such communication in reality exists. From all his facts—which are not numerous or striking —he "thinks himself authorized to say," that from the fifth week after conception until the end of pregnancy, the chorion and amnion are separated by a transparent, colourless, or slightly greenish-yellow layer. This layer, instead of being a simple serosity, is lamellated after the manner of the vitreous humour of the eye. It diminishes in thickness in proportion to the developement of the other membranes. The quantity of fluid, which its meshes enclose, is, on the contrary^ in an inverse ratio with the progress of gestation. It becomes gradually thinner and is ultimately formed into a homogeneous and pulpy layer, by being transformed into a simple gelatinous or mucous covering (enduit), which wholly disappears in many cases before the period of accouchement. Between the reticulated body, as M. Velpeau terms it, and the allantoid of oviparous animals, he thinks, there is the greatest analogy. Yet the fluid of the allantoid is very different from the urine, which is supposed, by some, to exist in the allantoid of animals. This fluid, we shall find, has been considered inservient to the nutrition of the new being, but, after all, it must be admitted, that our ideas regard- ing the vesicle, in man, are far from being determinate, for admitting— as elsewhere remarked—that it conveys the bloodvessels between the embryo and the chorion; the precise uses of its vesicular character and contents remain to be explained. 8. Erythroid vesicle.—This vesicle was first described by Dr. Pockels, of Brunswick, as existing in the human subject. It had been before 1 Haller, Elementa Physiol., viii 208. 2 Descript. Anat. Embryonis, Gotting., 1764. 3 Op. cit., p. 42. 4 Embryologie ou Ovologie Humaine. Paris. 1833. FCETAL PECULIARITIES. 563 observed in the mammalia. According to Pockels,1 it is pyriform; and much longer than the umbilical vesicle, although of the same breadth. M. Velpeau, however, asserts, that he has never been able to meet with it; and he is disposed to think, that none of the emmyos, depicted by Pockels, and by Seiler,2 were in the natural state. Such, too, is the opinion of Weber,3 and by the later embryologists the vesicle is not noticed. According to most obstetrical physiologists, when pregnancy is mul- tiple, the ova in the uterus are generally distinct, but contiguous to each other. By others, it has been affirmed, that two or more children may be contained in the same ovum, but this appears to require con- firmation. The placenta of each child, in such multiple cases, may be distinct; or the different placentae, having vascular communications with each other, may be united into one. At other times, in twin cases, but one placenta exists. This gives origin to two cords, and at others to one only, which afterwards bifurcates, and proceeds to both foetuses. M. Maygrier,4 however, and others5 affirm unconditionally, that there is always a placenta for each foetus; but that it is not uncommon, in double pregnancies, to find the two placentae united at their margins; the circulation of each foetus being distinct, although the vessels may anastomose. This was the fact in a case of quadruple pregnancy, communicated by M. Capuron to the Academie Royale de Medecine, Jan. 10th, 1837. c. Foetal Peculiarities. The head of the foetus is large in proportion to the rest of the body, and the bones of the skull are united b}' membrane; the sagittal suture extends down to the nose, so as to divide the frontal bone into two portions; and where this suture unites with the coronal, a quadrangular space is left, filled up by membrane, called anterior fontanelle or bregma. Where the posterior extremity of the sagittal suture joins the lamb- doidal, a triangular space of a similar kind is left, called posterior fan.- tanelle or posterior bregma. It is important for the obstetrical practi- tioner to bear in mind the shape of these spaces, as they indicate to him whether the anterior or posterior part of the head is the presenting part. The pupil of the eye, in a very young foetus, is entirely closed by a membrane, called membrana pupillaris, which arises from the inner margin of the iris, and continues there till the seventh month, when it gradually vanishes by absorption. It is a vascular substance, and, like the iris, to which it is attached, separates the two chambers of the eye from each other. WachendorfP first described it in 1738; and both he and Wrisberg detected vessels in it. Its vascularity was denied by Bichat, but it has been demonstrated by J. Cloquet.7 The 1 Isis, von Oken, p. 1342,1825. 2 Das Ei und Die Gabarmutter des Menschen, u. s. w.. p. 24, Dresd., 1832. 3 Hildebrandt, Handbuch der Anatomie, iv. 518, Braunsch., 1832. 4 Nouvelles Demonstrations d'Accouchemens, Paris, 1822-26. 6 Churchill, on the Theory and Practice of Midwifery, 3d Amer. edit., by Dr. Huston, p. 4d!), Philad., lbdb. 6 Comniero. Litterar. Noric, 1740 ; and Valentin, art. Foetus, Encycl. Worterb. u. s. w. xii. 376. 7 Memoire sur la Membrane Pupillaire, Paris, 1817. 564 FCETAL EXISTENCE. membrane is manifestly connected with the process of formation of the delicate organ to which it is attached; and according to Blumenbach,1 it keeps the iris expanded, during the rapid increase of the eyeball. In the upper part of the thorax of the foetus, a large gland, or rather glandiform ganglion exists, called thymus, and by Joseph Frank, cor- pus incomprehensibile. It is situate in the superior mediastinum, and lies over the top of the pericardium and arch of the aorta. It has two long cornua above, and two broad lobes below. Its appearance is glandular, and colour variable. In the progress of age it diminishes, so that in the adult it is -wasted, and in old age can scarcely be dis- covered amongst the areolar tissue. Krause,2 however, states, that he has found it in almost all individuals between twenty and thirty years of age, and often larger than in young children. The common idea is, that its greatest bulk is attained during the latter period of embryonic life; and that it must, consequently, exercise its chief functional ac- tivity during fcetal existence, and have some reference to the peculiari- ties of fcetal life. The observations of Krause do not sanction this idea; and the same may be said of those of Haugsted, who found not merely the absolute, but the relative size of the gland undergo a great increase after birth. Thus, whilst the weight of a dogs thymus at birth may range up to ten grains, it may subsequently increase with such rapid- ity, that after five months it may weigh nearly four hundred,—a pro- portional increase of forty times; whilst the weight of the entire animal has increased only twelve or sixteen times. Mr. Simon,3 from his researches, agrees fully with Haugsted, and infers, that "the thy- mus can with no more propriety be referred to the needs and uses of foetal life than the mammae of the female can be considered subserv- ient to the period of utero-gestation." The absolute increase of the gland appears to cease usually at about the age of two years. The gland is surrounded by a thin, areolar capsule, which sends prolongations into its interior, and divides it into numerous hollow lobules of unequal size, whose cavities communicate with a central reservoir, from which there is no outlet. Each lobule, according to Kolliker,4 may be regarded as a thick walled vesicle with protrusions, whose inner surface is even and continuous, whilst the outer is sub- divided into gland granules or acini by more or less deep fissures. The vesicles are filled with a milky fluid, the actual and ultimate na- ture of which is said to be expressed by the formula for protein. It is, therefore, highly nutrient. Sir Astley Cooper5 states, that the lobules may be drawn out and separated from each other in the man- ner of a string of beads, when their enveloping capsule has been re- moved. The ordinary weight of the thymus has been estimated at half an ounce; but this is probably above the average. Dr. Eoberts,' of New York, found the average weight, in the full-grown foetus, to 1 Institut. Physiolog., § 262. * Miillers Archiv., Heft 1, 1837. 3 A Physiological Essay on the Thymus Gland, Lond., Ifc45. 4 Amer. edit, of Sydenham Society's edition of his Manual of Histology, by Dr. Da Costa, p. 590, Philad.. 1854. 5 The Anatomy of the Thymus Gland, Amer. edit., p. 24. Philad., 1825. 6 Amer. Journ. of the Med. Sciences, Aug., 1837, Nov., 1Sy^. and Oct., 1841; New York Journ. of Med. and >urg., Jan., 1840: and New York Med. Gaz., July 21, lv41. Also, Dr. C. Lee, in Amer. Journ. of the Med. Sciences, Jan., 1842, p. 13S. FCETAL PECULIARITIES—THYMUS. 565 be 229 grains. The thymic arteries proceed from the inferior thyroid, internal mammary, bronchial, mediastinal, kc. The nerves proceed Fig. 500. Fig. 501. Section of Thymus Gland at the Eighth Month. 1. Cervical portions of gland ; independence of two lateral glands is well marked. 2. Secretory cells n-ea upon cut surface of section; these are observed iii all parts of section. 3, 3. Pores or openings of se- cretory ceUs and pouches ; they are seen covering whole internal surface of great central cavity or reser- voir. Continuity of reservoir in lower or thoracic portion of gland with cervical portion, is seen in the figure. from the pneumogastric, diaphragmatic, and inferior cervical ganglia. It has no excretory duct; and is one of the most obscure in its phy- siology of any organ of the body, although, like the lymphatic glands, it is probably connected with lymphosis and the function of nutrition. By Mr. Hewson,1 it was regarded as an appendage to the lymphatic glands for the more perfectly and expeditiously forming the " central particles of the blood" in the foetus, and in the early part of life. The fluid of the thymus has the appearance of chyle or cream, and contains a large number of corpuscles, which are smaller than the blood corpuscles, globular and oval in form; irregular in outline; va- riable in size; and provided with a small central nucleus.2 These have been long regarded as identical with the chyle and lymph cor- puscles. On treating the sliced thymus with ether, M. Eenaud3 found, that a considerable quantity of oleaginous matter was obtained from it; hence there is great resemblance between its composition, and that of chyle and milk. According to Mr. Simon,4 in hibernating animals, in which the 1 Works, Sydenham Society's edit., p. 280. Lond., 1846. 2 E. Wilson, System of Human Anatomy. 2d Amer. edit., p. 5Sb', Philad., 1S44. • London and Edinburgh Monthly Journal of Medical Science, March, 1843. 4 A Physiological Essay on the Thymus Gland, London, 1S45. Portion of Thymus of Calf, unfolded. a, Main canal; 6, glandular lobules; c, iso- lated gland-granules seated on the main canal. 566 FCETAL EXISTENCE. organ exists through life, as each successive period of hibernation ap- proaches, the thymus gradually enlarges, and becomes loaded with fat Fig. 502. Fig. 503. asverse section through an injected lo- bule of the Thymus in a child. Membranous investment of the lobule; b, ibrane of the gland-granules ; e, cavity of the le, from which the larger vessels branch out. which accumulates in it, and in fat glands connected with it, in even larger proportion than it does in the adipous tissue; and, accordingly, it has been inferred, that it may serve for the storing up of materials to be reabsorbed during the hibernating period, which may maintain at that time the respiration and temperature of the body; or, to em- ploy the language of Mr. Simon—" the gland fulfils its use as a sink- ing fund of nourishment in the service of respiration ;"—and a similar view appears to be embraced by Professor Ecker of Basle.1 The thyroid gland, which has been described in another place,2 and whose functions are equally obscure, Is also largely developed in the foetus; as well as the supra-renal capsules. The lungs, not having received air in respiration, are collapsed and dense, of a dark colour, like liver, and do not fill the cavity of the chest. Their specific gravity is greater than that of water, and con- sequently they sink in that fluid. On cutting into them, no air is emitted, and no hemorrhage follows. The absolute weight is, however, less; no more blood being sent to them than is required for their nutrition; whilst, after respiration is established, the whole of the blood passes through them; the vessels are consequently filled with blood; enlarged, and the organs themselves increased in absolute weight. Ploucquet asserts, from experiments, that the mean weight 1 Art. Blutgefassdriisen, in Wagner's Handworterbuch der Physiologie, 23ste Liefe- rung, S. 127, Leipzig, 1849. 2 Vol. i. p. 243. Section of Human Thymus, showing the large cavity in the wide portion and nume- rous orifices leading to its lobular cavities. Trai mem lobu FCETAL PECULIARITIES—CIRCULATORY APPARATUS. 567 of the lungs of a full-grown foetus, which never respired, is to that of the whole body as 1 to 70: whilst that of lungs in which respiration has been established is as 1 to 35, or doubled. These numbers can- not however, be considered to afford a satisfactory average,—the ex- ceptions being numerous; but they exhibit that, as might be expected, the absolute weight of the lungs is less, prior to the establishment of respiration. Careful and extended observations have satisfactorily shown, that although an increase in weight is generally found after respiration has been completely es- tablished, it is by no means the case when the inspirations have been feeble, as they often are for some hours and days after birth; and, on the other hand, it is not unusual to find, in infants that have not breathed, lungs as heavy as in the average of those that have. The subject is one of great interest as connected with infanti- cide; and has received much atten- tion in the different modern works on Medical Jurisprudence. It is, however, in the circulatory system of the mature foetus, that we meet with the most striking pecu- liarities. The heart is proportion- ably larger and more conical than in the adult. The valve of Eusta- chius—at the left side of the mouth of the inferior vena cava, where that vessel joins the sinus venosus —is larger than at an after period, and is supposed to direct the prin- cipal part of the blood of the as- cending cava directly through the opening that exists between the right and left auricle. This open- ing, which is called foramen ovale or foramen of Botal, is in the sep- tum between the auricles, and is nearly equal in size to the mouth of the inferior cava. It is situate obliquely; and has a membrane, forming a distinct valve, and some- what of a crescentic shape, which allows part of the blood of the right auricle to pass through the opening into the left auricle, but prevents its return. The pulmonary artery, instead of bifurcating as in the adult, divides u u Circulatory Organs of the Foetus. ]. Umbilical cord. 3. Umbilical vein dividing into three branches ; two (4 4) to be distributed to liver; and one (5), ductus venosus, which enters inferior vena cava (6). 7. Portal vein uniting with right hepatic branch. 8. Right auricle ; course of blood denoted by arrow, proceeding from S to 9, left auricle. 10. Left ventricle; blood following arrow to arch of aorta (11). Arrows 12 and 13, represent return of blood from head and upper ex- tremities through jugular and subclavian veins, to superior vena cava (14), to right auricle (8), and in course of arrow through right ventricle (15), to pulmonary artery (16). 17. Ductus arteriosus, the offsets at each side are right and left pulmo- nary arterv cut off. Descending aorta (18, 18), umbilical arteries (19), external iliacs (20). Ar- rows at termination of these vessels mark return of venous blood by veins to inferior cava. 568 FCETAL EXISTENCE. into three branches;—the right and left going to the lungs of the cor- responding side, whilst the middle branch,—to which the name ductus arteriosus is given,—opens directly into the descending aorta; so/that a great part of the blood of the pulmonary artery passes directly into that vessel. From the internal iliac arteries, two considerable vessels arise, called umbilical arteries. These mount by the sides of the blad- der, on the outside of the peritoneum, and perforate the umbilicus in their progress to the umbilical cord and placenta. The umbilical vein, which is also a constituent of the cord, and conveys the blood from the placenta to the foetus, arises from the substance of the placenta by a multitude of radicles, which unite together to form it. Its size is considerable. It enters the umbilicus, passes towards the inferior sur- face of the liver, and joins the left branch of the vena porta hepatica. Here a vessel exists called ductus venosus, which opens into the vena cava inferior, or joins the left vena hepatica where that vein enters the cava. A part only of the blood of the umbilical vein goes directly to the vena cava; the remainder is distributed to the right and left lobes of the liver, especially to the latter. The digestive apparatus exhibits few peculiarities. The bowels, at the full period, always contain a quantity of greenish, or deep black, viscid faeces, to which the term meconium has been applied, owing to their resemblance to the inspissated juice of the poppy (nxw, "a poppy"). It appears to be a compound of the secretions from the in- testinal canal and bile, and frequently contains down or fine hairs mixed with it. It has been analyzed by Dr. John Davy,1 and found to consist of:— Mucus and epithelium scales, Cholesterin (in plates) and margarin, Colouring and sapid matter of bile, and olein, Water, ..... 23-6 •7 3-0 72-7 100-0 Its ashes contained peroxide of iron and magnesia, with a trace of phosphate of lime and chloride of sodium. An analysis by Simon3 also exhibits that it contains the main constituents of bile :— Cholesterin, Extractive matter and bilifellinic acid, Casein, .... Bilifellinic acid and bilin, Biliverdin with bilifellinic acid, Cells, mucus, albumen, . Frerichs3 found it to yield on analysis :— Biliary resin, . . . . . Cholesterin, olein, and margarin, Epithelium, mucus, pigment, and salts,. 16-00 14-00 34-00 6-00 4.00 26-00 100-00 15-6 15-4 69- 100- The liver is very large; so much so as to occupy both hypochondriac regions; and the right and left lobes are more nearly of a size than in 1 Medico-Chirurgical Transactions, xxvii. 189, Lond., 1844. 2 Animal Chemistry, Sydenham Socifty's edition, ii. 3G7, Lond., 1846. 3 Kirkes and Paget, Manual of Physiology, 2d Amer. edit., p. 198, (note,) Philad., 1853. FCETAL PECULIARITIES—GENITAL ORGANS. 569 the adult. Prior to birth it would seem to be the only decarbonizing organ, the lungs being inactive; but as soon as respiration is esta- blished, less blood is sent to the liver; and this diminution takes place with great rapidity, and is usually evidenced a short time after birth by the comparative paleness of its substance. Hence it has been sup- posed, that the weight of the liver might aid in the determination of the question, whether a child had breathed or not. It has been shown, however, that although the liver, as a general rule, weighs less after respiration has been established, it is by no means the case when the inspiration has been feeble for hours or days after birth ; and, on the other hand, it is not uncommon to meet, in infants that have not breathed, with livers as light as in the average of those that have. In the small intestine and the hepatic ducts an albuminous fluid has been found by Drs. Prout and Robert Lee,1 which seemed to them to be separated from the blood, carried from the placenta to the liver, and to be indirectly inservient to the nutrition of the foetus. Dr. George Robinson2 also invariably found in the stomach of the foetus, during the latter period of its uterine existence, a peculiar substance, differing from the liquor amnii, and generally of a nutritious character, which he regards as the secretion of the salivary glands. The mixture of this substance with the liquor amnii is, he considers, the material submitted to the process of chymification in the foetal intestines. The urinary bladder is of an elongated shape, and extends almost to the umbilicus. The muscular coat is somewhat thicker and more irritable than in the adult, and it continues to possess more propor- tionate power during youth. The common trick of the schoolboy—of sending a jet of urine over his head—is generally impracticable in more advanced life. From the fundus of the bladder, a ligament of a conical shape, called urachus, ascends between the umbilical arteries to the umbilicus; becoming confounded there with the abdominal apo- neuroses, according to Bichat; and forming a kind of suspensory ligament to the bladder. It is sometimes found hollow in the human foetus, but Bichat considers such a formation to be preternatural. In the foetal quadruped, it is a large canal, which transmits urine to the allantois, of which, as well as of other fcetal peculiarities, we have previously treated.3 From examinations of the foetal urine, made by Dr. William D. Moore,4 he concludes—admitting, however, that the subject has as yet been most imperfectly dealt with—that it would appear to be an albu- minous fluid, of feeble reaction, free from sugar, containing some of the usual salts of the urine, abounding in a highly nitrogenized principle, probably allantoin, but affording no urea, and depositing a most re- markably large amount of nucleated epithelium. Lastly, the genital organs of the foetus require notice. The suc- cessive developement of this part of the system has given rise to some singular views regarding the cause of sex. During the first few 1 Lectures on the Theory and Practice of Midwifery, Amer. edit., p. 145, Philad., 1844. ' 2 London and Edinburgh Monthly Journal of Medical Science, Jan., 1847, p. 507. 3 Page 537. 4 Dublin Quarterly Journal of Medical Scienoe, August, 1855, p. 88. 570 FCETAL EXISTENCE. weeks, the organs are not perceptible; but, about the termination of the fifth, a small cleft eminence appears, which is the rudiment of the scrotum, or of the vulva, according to the sex. In the sixth week, an aperture is perceptible, common to the anus and genital organs, in front of which is a projecting tubercle. In the seventh and eighth weeks this tubercle seems to be tipped by a glans, and grooved beneath by a channel which extends to the anus. In the eleventh and twelfth, the perineum is formed and separates^ the anus from the genital organs. In the fourteenth the sex is distinct; but there still remains, for some time, a groove beneath the clitoris or penis, which becomes closed in the former, and made into a canal in the latter. This striking simi- larity between the male and female organs has led Tiedemann1 to con- clude, that the female sex is the male arrested at an inferior point of organization. In his view, every embryo is originally female; the cleft, described above, being the vulva,—the tubercle, the clitoris: to con- stitute the male sex, the cleft is united so as to form a raphe; the labia majora are joined to form the scrotum; the nymphae to form the ure- thra, and the clitoris is transmuted into a penis. In support of this opinion, he asserts, that the lowest species of animals are almost all females; and that all the young acephali and aborted foetuses, which have been examined, are of that sex. Others, again, assert, that the sexes are originally neuter, and that the future sex is determined by accidental circumstances during the first week of fcetal life; whilst M. Velpeau is disposed to believe, that they are all male—the infrapubic prolongation existing in every embryo, although there may be neither labia majora nor scrotum. Admitting, however, that the embryo be- longs to either the one or the other sex, or is neutral, we must still remain at a loss regarding the influences that occasion the subsequent mutations ; and it seems impossible not to admit, that although an ap- parent sexual identity may exist among different embryos, there must be an instinct or force of impulsion seated somewhere, which gives occasion to the sex being ultimately male or female, in the same man- ner as it causes the young being to resemble one or other parent in its external or internal configuration; and if our means of observation were adequate to the purpose, a distribution of arteries or nerves might perhaps be detected, which could satisfactorily account ab initio for the resulting sex. In the absence of such positive data, M. Geoff'roy St. Hilaire has hypothetically suggested, that the difference of sex may be owing to the distribution of the two branches of the spermatic artery. If they continue in approximation, proceeding together,—the one to the testicle, the other to the epididymis,—the individual is male; if they separate,—the one going to the ovary, the other to the cornua of the uterus,—the individual is female. The degree of predominance of the cerebro-spinal system, he thinks, determines the approximation or separation of the two arterial branches. This predominance being greater in the male, the spermatic arteries are more feeble, and conse- quently in greater proximity; and conversely in the female ;2 but this suggestion does not remove the obscurity. 1 Anatomie der Kopflosen Missgeburten, S. 54, Landshut, 1813. 2 Adelon, Physiologie de l'Homme, 2de edit., iv. 375. FCETAL PECULIARITIES — DESCENT OF THE TESTES. 571 Leaving these phantasies of the generalizing anatomists on a sub- ject regarding which we must, pro- bably, ever remain in the dark, let us inquire into the phenomena of the descent of the testes in the foetus. In the early months of fcetal life, the testicle is an abdominal viscus, seated below the kidney. About the middle of the third month, it is about two lines long, and situate behind the peritoneum, which is reflected over its ventral surface. At this time, a sheath of peritone- um may be observed, passing from the abdominal ring to the lower part of the testicle, and containing a ligament, called by Mr. Hunter, who first described it, gubernacu- lum testis, which generally has been considered to be formed of elastic areolar tissue, proceeding from the upper part of the scrotum, and from the part of the general apo- neurosis of the thigh near the ring. Mr. Curling1 describes it as surrounded by a thin layer of striped Descent of the Testicle. A. Testicle in scrotum. B. Prolongation of peri- toneum. C. Peritoneum lining abdomen. D. Peri- toneum forming tunica vaginalis. E. Cavity of peritoneum. P. Kidney. Fig. 506. Fig. 507. Diagrams illustrating the descent of the Testis. Fig. 506. 1. The testis. 2. The epididymis. 3, 3. The peritoneum. 4. The pouch formed around the testis by tlie peritoneum. 5. The pubic portion of the cremaster attached to the lower part of the testis. 6. The portion of the cremaster attached to Poupart's ligament. The mode of eversion of the cremaster is shown by these lines. 7. The gubernaculum, attached to the bottom of the scrotum, and becoming shortened by the contraction of the muscular fibres which surround it. 8, 8. The cavity of the scrotum. 9. The peritoneal cavity. Pig. 507. In this Figure the Testis has completed its descent. The Gubernaculum i3 shortened to its utmost, and the Cremaster is completely everted. The pouch of Peritoneum above the Testis is compressed so as to form a Tubular Canal. 1. A dotted line marks the point at which the tunica vaginalis will terminate superiorly ; and figure 2 its cavity. 3. The peritoneal cavity. muscular fibres, the cremaster, which pass upAvards to be attached to the testis; inferiorly the fibres having the same attachments as the 1 Lond. Lancet, April 10, 1841, p. 70 ; Practical Treatise on the Diseases of the Testis, p. 32. Lond., ls4H, 2d Amer. edit., Philad., 1856; and Art. Testicle, Cyclopaedia of Anatomy and Physiology, Pt. xxxviii. p. 982. February, 1850. 572 FCETAL EXISTENCE. cremaster, and being in reality the cremaster inverted. The descent of the testis is effected by the traction of these fibres. Durino- the descent, "the muscle of the testis is gradually everted, until, when tha transition is completed, it forms a muscular envelope external to the process of peritoneum, which surrounds the gland and the front of the cord." Prof. E. H. Weber1 has a similar view. He affirms, as the result of experiments on man, rabbits, and beavers, that the guberna- culum originates in the form of a sac in the situation of the inguinal canal. The lower end of this sac extends to the bottom of the scro- turn, the upper end extends through the internal abdominal ring as high as the testis, carrying up along with it, to the fold by which that oro-an is suspended, fibres from the internal oblique muscle. By the aid of the contraction of these fibres, a kind of inversion (Einstiilpung) or intussusception of the hollow gubernaculum is induced. Kolliker,3 too, describes the gubernaculum as a process composed of transversely striated and smooth muscles. The head of the foetus in utero being the lowest part, the testis has necessarily to ascend into the scrotum, and consequently some force must be exerted upon it. This is supposed to be effected by the con- traction of the gubernaculum testis. About the seventh month, the testes are in progress towards the scrotum, and have attained the inner ring. In this descent, the organ abandons successively one portion of the peritoneum to pass behind another immediately below, until the lowest part of the pouch, formed by the peritoneum, around the t s- ticle as in Figs. 505-6-7, becomes the tunica vaginalis testis; whilst the portion of peritoneum, that descended before the testicle, becomes, when the testicle has fully descended, the second coat or tunica vagi- nalis. As soon as the testicle has reached the lower part of the scrotum, the neck of the pouch approaches a closure, and this is commonly effected at birth. Sometimes, however, it remains open for a time; the intestines pass down, and congenital hernia is thus induced. The testes have not always descended into the scrotum at birth, even at the full period; of 97 new-born infants, Wrisberg found both of them in the scrotum in 67: one or both in the canal in 17; one testis in the abdomen in 8; and both in the abdomen in 3.3 Sometimes, as has been remarked elsewhere, one or both testes remain through life in the abdomen, a condition which is natural in the ram. 2. PHYSIOLOGY OF THE FCETUS. In investigating this interesting point of human physiology, we shall inquire into the functions, in the order adopted respecting the functions of the adult. On many of the topics that wall have to engage atten- tion, it will be found that the deepest obscurity rests, whilst the hypo- theses indulged regarding them have been of the most fanciful and mystic character. 1 Muller's Archiv. fiir Anatomie u. s. w. H. v., s. 403, Jahrgang, 1847. 2 Mikroskopische Anatomie, ii. 420, Leipz., 1854; and Sydenham Society's edit, of his Manual of Histology, Amer. edit., p. 635, Philad., 1S54. 3 Comment. Soc. Reg. Scient., Gotting., 1778. FUNCTIONS OF NUTRITION. 573 a. Functions of Nutrition. These functions are not as numerous in the foetus as in the adult. Their object is, however, the same,—the formation of the various parts of the organized machine, and their constant decomposition and reno- vation. One of the least tenable hypotheses, that have been entertained re- garding the embryo at its first formation is,—that, for the first month __and why the period is thus limited is not apparent—the vitality of the foetus is not independent, but is a part,—an offset, as it were,—of that of the mother; that it has no separate powers of existence; no faculty of self-evolution;' and that its organs are nourished by the plastic materials, which it incessantly derives from the maternal blood. It appears manifest, that from the very moment of the union of mate- rials furnished by both sexes at a fecundating copulation, the elements of the new being must exist; and that it must possess, within itself, the faculty of self-evolution ; otherwise, how can we understand the phenomena, that take place in the ovary after fecundation. It is admitted, that this organ furnishes the unfecundated ovum ; and that the sperm must come in contact with it; after which, fecundation is accomplished, and immediately the ovum undergoes a farther deve- lopement ; escapes, in due time from the viscus in which it was formed; is laid hold of by the Fallopian tube; passes through that canal, and is deposited in the interior of the uterus, with which it ultimately contracts adhesions. But all this requires time. The ovum does not probably reach the uterus, in the human female, before ten or twelve days; and some time must still elapse before such adhesions are effected; and, consequently, before anything like maternal blood, whence the plastic materials are derived, according to the view in question, could be sent to it. During this time, the embryo must derive its nourish- ment from the nutritious matters with which it is surrounded in the ovum, in the same manner as the young of the oviparous animal, dur- ing incubation, obtains the nutriment necessary for its full develope- ment from the matters surrounding it. The albuminous and oily contents of the ovum, surrounding the embryo of the oviparous animal, would seem to resemble greatly the milk of the mammalia both physically and chemically, and M. Joly1 has suggested the following points of similarity. " The milk is com- posed essentially of fatty matter—butter, suspended under the form of globules in an albuminoid fluid—casein ; and it contains water, sugar of milk, and salts; amongst others, phosphate of lime, so eminently useful for the consolidation of the bones of the young being that feeds upon it. In the egg there are vitelline globules, which contain a fat oil, susceptible of congelation on cooling,—evidently the analogue of butter and the globules that contain it. In the egg are, likewise, albumen, and vitelline, which is a very slight modification of it. Now, it is admitted by chemists, that albumen, vitelline, animal protein and animal fibrin differ so little from casein, that all these substances may be, and in fact are, confounded under the common denomination of 1 Comptes Rendus, No. 20, 12 Novembre, 1S49, p. 524. 574 F03TAL EXISTENCE. albuminoid or proteiform matters. Moreover, Wincklef, Barreswil and, quite recently, M. Braconnot, from whom I have learned this interesting fact, have discovered sugar of milk in eggs; and every one is aware that, as in the milk itself, water and salts are found and par- ticularly phosphate of lime. It may be added, that on treating the hen's egg like the milk of the mammalia, and by the same chemical agents (alcohol, sulphuric ether, and acetic acid), I have obtained almost the same reactions." In due time, after the ovum has reached the interior of the uterus it is compelled to absorb appropriate nutriment from the mother;— the minute quantity existing in the ovum, at this early period, being insufficient for the developement which it is destined to attain. In this last respect, the human ovum differs from the egg of an oviparous bird, which is hatched out of the body, and contains sufficient nutriment for full fcetal evolution. In treating of this subject, Dr. Granville1 has the following remarks.—" What stronger proof need be required of the existence of an adherent life principle in the ovulum, which is, at one time at least,—indeed, I suspect throughout the period of gestation,— independent of any connexion with the parent mother? Yet none of the earlier writers who adopted the ovarian theory of generation have ever asked themselves this question:—what supports the vitality of a fecundated ovulum after it has left the ovarium, and previously to its becoming connected with the womb? In fact, the subject had never been mooted, before the more modern physiologists took it up and satisfactorily explained it:"—and he adds in a note:—"the whole of the English physiologists, writers on midwifery, and lecturers, whe- ther ancient or modern, are entirely silent on this important stage of embryonic life." It is a topic, however, discussed at length in the first edition of this work, which was published before that of Dr. Granville, and is much expanded in the subsequent editions.2 Since the time of Hippocrates, Aristotle, and Galen, different ana- tomists and physiologists have asserted, that the umbilical vein is the only channel through which nutriment reaches the foetus; in other words, that the whole of the nourishment which it receives is from the placenta; but the facts, to which allusion has already been made, are sufficient to overturn this hypothesis. It is impossible, that the pla- centa can have any agency until it is in esse. Such an explanation of the process of foetal nutrition could only hold good after the first periods, and then, as we shall see, it is sufficiently doubtful. Accord- ingly, some of the most distinguished modern physiologists, who have devoted their attention to embryology, have completely abandoned the idea of placental agency during the first months; and they, who have invoked it at all, have usually done so as regards the after periods only. On all this subject, however, we have the greatest diversity of views. Lobstein,3 for example, affirms, that the venous radicles of the rudimental placenta obtain nutritive fluids from the mother during the first days only, until the period when the arteries are formed; but that, after this, all circulation between the uterus and placenta ceases, 1 Graphic Illustrations of Abortion, p. vii., Lond., 1834. 2 Human Physiology, 1st edit., ii. 305, Philad., 1832. 3 Essai sur la Nutrition du Foetus. Strasbourg, 1802. NUTRITION OF THE FCETUS. 575 and the fluid of the umbilical vesicle, the liquor amnii, and the jelly of the cord, are the materials of nutrition. Meckel1 thinks the placenta is never the source of nutritive materials. He regards it as an organ for the vivification of the blood of the foetus, analogous to the organ of respiration in the adult; and nutrition is, in his opinion, accomplished by the matter of the umbilical vesicle in the beginning, by the liquor amnii until midterm, and by the jelly of the cord until the end. Ac- cording to M. Beclard,2 nutrition is effected, during the first weeks, by the fluid of the umbilical vesicle; afterwards, by the liquor amnii, and the jelly of the cord ; and as soon as the ovum becomes villous, and developes the placenta, by that organ. Dr. Montgomery3 has described several " decidual cotyledons," as he terms them, which are best seen about the second or third month, and are not to be found at the ad- vanced period of gestation. These are small cup-like elevations on the external surface of the decidua uteri, having the appearance of lit- tle bags, the bottoms of which are attached to, or embedded in, its sub- stance ; they then expand a little, and again grow smaller towards their outer or uterine end, which, in by far the greater number of them, is an open mouth when separated from the uterus: how it may be when adherent he does not profess to say, nor does he offer any decided opinion as to their precise nature or uses; but, from having on more than one occasion observed within their cavity a milky or chylous fluid, he is disposed to consider them reservoirs for nutrient fluids separated from the maternal blood, to be thence absorbed for the sup- port and developement of the ovum. " This view," says Dr. Mont- gomery, "seems strengthened when we consider, that at the early periods of gestation, the ovum derives all its support by imbibition, through the connexion existing between the decidua and the villous processes covering the outer surface of the chorion." M. Adelon4 is of opinion, that two sources of nutrition ought alone to be admitted,—the umbilical vesicle, which is the sole agent for nearly two months, and the placenta for the remainder of the period. M. Velpeau5 equally thinks, that the nutriment of the ovum is derived from different sources at different periods of intra-uterine existence. The embryo, he says, is at first but a vegetable, imbibing the surrounding humours. The villi of its circumference, which are true cellular spongioles, obtain nu- tritive principles in the Fallopian tube and the uterus, to keep up the developement of the vesicles of the embryo; after which the new being is nourished like the chick in ovo, or rather like the plantule, which is, at first, altogether developed at the expense of principles enclosed in its cotyledons. It gradually exhausts the vitelline substance contained in the umbilical vesicle. The emulsive substance of the reticulated sac of the allantoid pouch is also gradually absorbed. The end of the second month arrives; the vessels of the cord are formed, and the pla- centa is developed; by its contact with the uterus, this organ obtains 1 Handbuch, u. s. w., Jourdan and Breschet's French translation, iii. 1784. 2 Enibryologie ou Essai Anatomique sur le Fetus Humain, Paris, 1821. 3 Signs and Symptoms of Pregnancy, p. 133, Lond., 1837. 4 Physiologie de l'Homme. 2de edit., iv. 397, Paris, 1829. 6 Embryologie ou Ovologie, &c, Paris, 1833 ; and Traite Elementaire de l'Art des Ac- coucheniens, Professor Meigs's translation, 2d edit., p. 213, Philad., 1838. 576 F03TAL EXISTENCE. reparatory materials; elaborates them ; and forms from them a fluid more or less analogous to blood, which fluid is absorbed by the radi- cles of the umbilical vein. The views of Professor Goodsir on this subject have been referred to already.1 We find, consequently, some of the most distinguished physioloo-ists denying—as it would seem that every one ought to do—that the nu- trition of the foetus takes place solely from blood sent by the mother to the foetus. If we search into the evidence afforded by transcenden- tal anatomy, we find that amidst the various singular monstrosities met with, there would appear to be but one thing absolutely necessary for foetal developement,—an absorbing surface, surrounded by a nutri- tive substance, capable of being absorbed. Head and heart may be wanting, and yet the foetus may grow so as to attain its ordinary dimen- sions. We have the most incontestable evidence, that neither the pla- centa nor umbilical cord is indispensably necessary for fcetal develope- ment. M. Adelon disposes of this in the most summary manner, by affirming, that " there is no authentic instance of a foetus, devoid of umbilical cord and placenta, attaining full uterine growth." The case is not, however, got rid of so easily. Marsupial and monotrematous animals are non-placental, or breed their young without either positive placenta or cord. The embryos are enclosed in one or more mem- branes, which are not attached to the coats of the uterus, and they are supplied with nourishment from a gelatinous matter by which they are surrounded. Thomas Bartholin, during his travels in Italy, saw an individual, forty years old, who was born without anus, penis, or um- bilicus; and M. Velpeau cites similar cases from Kuysch, Samson, Chatton, Rommeil, Denys, Fatio, V. Geuns, Sue, Penchienati, Franzio, Desgranges, Kluyskens, Pinel, Mason, Osiander, Dietrich, Von Froriep, and Voisin ; but as these cases militate against his views of embryo- trophy, he attempts to diminish their force by affirming, that the observations, which he had made, satisfy him, that all the foetuses thus born had died in utero, in consequence of the destruction of the cord, or the closure of the umbilicus; or else, that the umbilicus existed, but was hidden or lost in the extroversion of the bladder almost always remarked in those that lived. Passing by the singular deduction of M. Velpeau, that his observations have satisfied him of the incorrect- ness of those made by observers, many of whom have long since left the stage,—long before he existed,—as well as the facts relating to the marsupial animal, and that the foetus, in extra-uterine pregnancies, has frequently no placenta,—with the case cited by Dr. Good, from Hoff- mann, of a foetus born in good health and vigour, the funis sphacelated and divided into two parts; and one by Stalpart Van der Wiel,2 of a living child, exhibited without any umbilicus as a public curiosity,— a case observed by Dr. Good3 himself, appears to be unanswerable. The case in question occurred in 1791. The labour was natural; the child, scarcely less than the ordinary size, was born alive; cried feebly 1 Pages 552, 557. 2 Observat. Rar. Med.-Chirurg., cent, ii., p. 1, Obs. 32. 8 Case of Preternatural Fcetation with Observations, read before the Medical Society of London, Oct. 20, 1794; and Study of Medicine, in Physiological Proem to Class v. Genetica. NUTRITION OF THE FfETUS. 577 once or twice after birth, and died in about ten minutes. The organi- zation, both internal and external, was imperfect in many parts. There was no sexual character; neither penis nor pudendum ; nor any inter- nal organ of generation. There was no anus, no rectum, no funis, no umbilicus. The minutest investigation could not discover the least trace of any. With the use of a little force, a small, shrivelled pla- centa,—or rather the rudiment of a placenta,—followed soon after the birth of the child, without funis or umbilical vessels of any kind, or any appendage by which it appeared to have been attached to the child. In a quarter of an hour afterwards, a second living child was protruded into the vagina and delivered with ease, being a perfect boy, attached to its placenta by a proper funis. The body of the first child was dissected in the presence of Dr. Drake of Hadleigh, and of Mr. Anderson of Sunbury, to both of whom Dr. Good appeals for the cor- rectness of his statement. In the stomach, a liquor was found resem- bling liquor amnii. How could nutrition have been effected, then, in this case ? Cer- tainly not by blood sent from the mother to the child, for no apparatus for its conveyance was discoverable; and are we not driven to the necessity of supposing, that nutriment must have been obtained from the fluid within the ovum ? This case,—with the arguments already adduced,—seems to constrain us to admit, that the liquor amnii may have more agency in the nutrition of the new being than is generally granted. Professor Monro,1 amongst other reasons,—all of which are of a negative character,—for his disbelief in this function of the liquor amnii, asserts, that if the office of the placenta be not that of affording food to the embryo, it becomes those, who maintain the contrary doc- trine, to determine what other office can be allotted to it; and that till this is done it is more consistent with reason to doubt the few and unsatisfactory cases, at the time brought forward, than to perplex our- selves with facts directly contradictory of each other. The case given by Dr. Good, since Professor Monro's remarks were published, is so unanswerable, and so unquestionable, that it affords a positive fact of full, or nearly full, fcetal developement, independently of placenta and umbilical cord; and the fact must remain, although our ignorance of the functions of the placenta may be " dark as Erebus."2 1 Edinburgh Medical Essays, ii. 102. 2 The following case, with which the author was obligingly favoured by his friend, Dr. Wright, of Baltimore, has an instructive bearing upon the subject. The condition of the placenta was such as to lead that intelligent observer to conclude, that any cir- culation between the mother and the fetus, through the placenta, was impracticable. " Baltimore, September 26th, 1835. " Dear Sir,—In compliance with your request, I offer you the following plain and Short statement of a case, which occurred in my practice, at the date indicated. "On the 6'th of December, 1833, I was requested to visit Mrs. T----, of this city,—a young woman of large frame, good constitution, and generally excellent health. She had been married about fifteen months, and I was now called to attend her first labour. She had felt occasional labour pains through the day, and was delivered of a fine, vigorous female infant, in about four hours from the time of my call. The labour was, in all respects, natural, and as easy as is common—or consistent—with a first parturi- tion. After the birth of the child, an hour, perhaps, was passed in waiting for second- ary pains to effect the expulsion or favour the removal of the placenta, but no move- ment of this kind having then occurred, a gentle examination was made to ascertain VOL. II.—'61 578 F03TAL EXISTENCE. That the liquor amnii is possessed of nutritive properties is shown not only by its containing albumen, and, it is said, osmazome; and by the fact, that new-born calves have been nourished for a fortnight on fresh liquor amnii ;J but amongst those physiologists, who admit it to be a fluid destined for fcetal nutrition, a difference prevails regarding the mode in which it is received into the system. Osiander,2 Brugmans3 Van den Bosch, Fohmann, Cams,4 and others, think it is absorbed through the skin. In the fcetal state, the cuticle is extremely thin, and, until within a month or two of the full period, can be scarcely said to exist. There is not, consequently, that impediment to cutaneous absorp- tion which, we have seen, exists in the adult. The strong argument, however, which they offer in favour of such absorption is the fact, that the foetus has been developed, although devoid of both mouth and umbilical cord; and Professor Monro, in opposing this function as- whether that body might be easily and properly taken away. The vagina contained nothing more than the funis—the outlet of the uterus was open, soft and extensible. The cord was gently followed into the uterine cavity, and the cake found near ita fundus, retaining a close connexion with the uterus. The placental mass was large and firm, presenting to the touch a peculiar feeling—as of a dense sponge, full of coarse, granular or gravelly particles. Deeming it now proper to relieve the patient fully, a cautious effort was made to detach the placenta from the uterus, in order to its manual extraction. In pursuing this design, it was found, that the adhering surface of the former consisted of a uniform calcareous lamina or plate, rough to the finger, and ex- citing such a sensation or feeling as would be caused by a sheet of coarse sand-paper. When the mass was detached, aud brought away, the laminar surface, just referred to, was found to be a calcareous plate, uniformly covering the whole of the attached por- tion of the cake,—the entire surface of the utero-placental connexion. The calcareous matter, thus distributed, was thin, and readily friable, but, as before remarked, it appeared to constitute a uniform and superficial covering. The correspondent uterine surface—the part from which the placenta had been separated—felt rough, but com- paratively soft, imparting nothing distinctly of the calcareous or gritty feel. Out of the body, the placenta felt heavy, and eminently rough throughout. When compressed or rubbed together, the large amount of nodular or granular matter, dispersed through its substance, was not only manifest to the touch, but a very audible crepitation or grating sound could be thus elicited from any and every part of the mass. " In this uncommon instance of placental degeneracy, both the mother and child were perfectly healthy and well. The latter, indeed, was remarkable for its fine size, perfect nutrition and vigour. From the condition of the cake, and the character of ita adhesion to the uterus, I apprehended a more than ordinary liability to secondary affec- tion, in the form of puerperal fever,—and whether influenced or not by the circum- stances detailed, secondary fever did ensue on the third day from delivery, attended by the usual signs of puerperal hysteritis, which affection, however, was happily sub- dued by general and topical bleeding, calomel, &c. • " With sincere regard, yours, " T. H. Wright. " Professor Dunglison. " P. S.—The child, referred to, is living, and, from its birth to the present, has con- siderably exceeded the common bulk of children at the same age. The mother is now far advanced in her second pregnancy." After this letter was written, the same lady was delivered of another healthy child. The maternal surface of the placenta was of the like calcareous character; but the deposition was not to the same extent as in the first pregnancy. A similar case ha« been described by Mr. Gilbert, of Beaminster, England.* 1 Cazeaux, Traite Theorique et Pratique de l'Art des Accouchements, p. 176, Paris, 1840. 2 Handbuch der Entbindungskunde, B. i., S. 237. 3 De Natura, et Utilitate Liquoris Amnii, Ultraject., 1792. 4 Lehrbuch der Gynakologie, Th. ii., S. 27, Leipz., 1828. * Lancet, for Dec. 16, 1837, p. 418. NUTRITION OF THE FCETUS. 579 cribed to the liquor amnii, refers to cases of monstrous formation, in which no mouth existed, nor any -kind of passage leading to the stomach. Others, as Haller1 and Darwin,2 are of opinion, that the fluid enters the mouth and is sent on into the stomach and intestines; and in support of this view they affirm, that the liquor amnii has been met with in these organs. Heister, on opening a gravid cow that had perished from cold, found the liquor amnii frozen, and a continuous mass of ice extending to the stomach of the foetus.3 Observations, by Dr. George Robinson,4 on fcetal animals more especially, have led him to affirm, that in the earlier stages of the developement of the foetus, the contents of the stomach consist chiefly of liquor amnii, to which a peculiar matter is added, which—as before remarked—he refers to the salivary glands. He states, moreover, that the liquor amnii continues to be swallowed until birth, and the mixture of this with the peculiar salivary secretions is the material subjected to chymification; yet he ascribes the main agency in fcetal nutrition, in the later months, to the " placental vessels." Physiologists who believe, that the liquor amnii is received into the stomach, differ as to what happens to it in that organ. Some suppose, that it is simply absorbed without undergoing digestion; others, that it must be first subjected to that process. According to the former opinion, it is simply necessary, that the fluid should come in contact with the mucous membrane of the alimentary passages; and they affirm, that if digestion occurs at all, it can only be during the latter months. Others, however, conceive, that the waters are swallowed or sucked in, and undergo true digestion. In evidence of this they adduce the fact of meconium existing at an early period in the intestinal canal, which they look upon as evidence that the digestive function is in action; and, in further proof, they affirm, that on opening the abdo- men of a new-born infant the chyliferous vessels were found filled with chyle, which could not, they say, have been formed from any other substance than the liquor amnii; and lastly, that fine silky down has been found in the meconium, similar to that which exists on the skin of the foetus, and which is conceived to have entered the mouth along with the liquor amnii. These reasons have their weight, but they cannot explain the developement in the cases above alluded to, in which there was no mouth; and of course cannot apply to the acepha- lous foetus. Moreover, it has been properly remarked, that the presence of meconium in the intestinal canal—admitting that it is the product of digestion, which is denied by many—merely proves, that digestion has taken place, and the same may be said of the chyle in the chyliferous vessels: neither one nor the other is a positive evidence of digestion of the liquor amnii. Both might have proceeded from the stomachal secretions. It has also been affirmed, that meconium exists in the intestines of the acephalous foetus ; and in those in which the mouth is imperforate. Lastly, with regard to the down discovered in the me- conium, it has been suggested as possible, that it may be formed by 1 Elementa Physiologic, viii. 205. 2 Zoonomia, vol. ii. p. 203, London, 1801. 8 Adelon, Physiologie de l'Homme, iv. 389, Paris, 1829. 4 London and Edinburgh Monthly Journal of Medical Science, Jan., 1847, p. 512. 580 FfETAL EXISTENCE. the mucous membrane of the intestine, which so strongly resembles the skin in structure and functions. Others have supposed, that the liquor amnii is received through the respiratory passages, from the circumstance, that in certain cases the fluid has been found in the trachea and bronchia;—some presuming, that it readily and spontaneously enters the nostrils and passes to the trachea and bronchia; others, that it is forced in by the pressure of the uterus; and others, again, that it is introduced by the respiratory movements of the foetus. Views have differed in this case, also, regard- ing the action exerted upon it after introduction; some presuming that it is absorbed immediately; others, that it is inservient to a kind of respiration; and that, during fcetal existence, we are aquatic animals, " —consuming the oxygen or atmospheric air, which Scheele,1 Lassaigne,' and others have stated to exist in it. It is scarcely necessary to oppose these gratuitous speculations seriously. The whole arrange- ment of the vascular system of the foetus, so different from that which is subsequently established, and the great diversity in the lungs, prior ' and subsequent to respiration, would be sufficient to refute the idea,— had it even been shown, that the liquor amnii always contains one or other of these gases, which is by no means the fact. The case of the acephalous foetus is likewise an obstacle to this view as strong as to that of the digestion of the liquor amnii. As if to confirm the remark of Cicero—"nihil tarn absurdum, quod non dictum sit ab aliquo philosophorum,"—it has been advanced by two individuals of no mean pretensions to science, that the liquor amnii may be absorbed by the genital organs, or by the mammas. Lobstein3 supports the former view; Oken4 the latter. Oken asserts, that the fluid is received by the mammae, elaborated by them, and thence conveyed into the thymus gland, the thoracic duct, and the vascular system of the foetus. Hence, the necessity of both sexes possessing nipples before birth. Of these various opinions, the one that assigns the introduction of the fluid to the agency of the cutaneous absorbents appears to carry with it the greatest probability. It must be admitted, however, that the whole subject is in obscurity, and requires fresh, repeated, and accurate experiments and observations. But it may be asked, with Dr. Monro, what are the nutritive functions performed by the placenta? We have before alluded to the different views enter- tained regarding the connexion between the placenta and the uterus. Formerly, it was universally maintained, that vessels pass between the mother and the maternal side of the placenta, and that others pass between the foetus and the fcetal side, but that the two sides are so dis- tinct, as to justify their being regarded as two placentae,—the one maternal, the other foetal,—simply united to each other. At one time, again, it was supposed, that a direct communication exists between the maternal and fcetal vessels, but this notion has long been exploded. We have decisive evidence, that the connexion is of the most indirect nature. Wrisberg made several experiments, which showed, that the 1 De Liquoris Amnii Utilitate, Copenhag., 1795. 2 Archiv. General, de Med., ii. 308. 3 Essai sur la Nutrition du Foetus, p. 102, Strasbourg, 1802. 4 Zeugung, p. 102, Bamberg, 1805. NUTRITION OF THE FG3TUS. 581 circulatory apparatus of the foetus is not drained when the mother dies of hemorrhage. It has been affirmed, too, that if the uterine arteries be injected, the matter of the injection passes into the uterine veins, after having been effused into the lobes of the placenta. If, on the other hand, the injection be thrown into the umbilical arteries it passes into the umbilical vein, and is effused into the placenta, but does not enter the uterine vessels. When, however, an odorous substance, like camphor, is injected into the maternal veins of an animal, the foetal blood ultimately assumes a camphorated odour; when animals have been fed on madder during gestation, the colouring matter has been found in the foetus;1 and, when the human female has taken rhubarb, evidence of it has been found in the liquor amnii, in the serum of the blood of the umbilical vessels, and in the first urine of the infant.2 M. Magendie3 injected this substance into the veins of a gravid bitch, and extracted a foetus from the uterus at the expiration of three or four minutes; the blood did not exhibit the slightest odour of camphor; whilst that of a second foetus, extracted at the end of a quarter of an hour, exhibited it decidedly. Such was the case, also, with the other foetuses. The communication may, however, have been owing to the same kind of transudation and imbibition, of which we have spoken under the head of Absorption, and might, consequently, be regarded as entirely adventitious; and the fact of the length of time required for the detection of the odorous substance favours the idea; for if any direct communication existed between the mother and foetus, the trans- mission ought certainly to have been effected more speedily. The transmission of substances from the foetal to the maternal placenta is still more difficult. M. Magendie was never able to affect the mother by poisons injected into the umbilical arteries, and directed towards the placenta; and he remarks, in confirmation of the results of the experiments of Wrisberg, that if the mother dies of hemorrhage, the vessels of the foetus remain filled with blood. They who consider, that there is no maternal and fcetal portion of the placenta, or, rather, that it is all fcetal, of course believe, where the matter of injection, thrown into the uterine vessels, has passed into the cells of the placenta, that it has been owing to the rupture of parts by the force with which the injection has been propelled. Another fact, which proves the indirect nature of the connexion that exists between the parent and child, is the total want of correspond- ence between the circulation of the two. By applying the stethoscope to the abdomen of a pregnant female, the beating of the fcetal heart is observed to be twice as frequent as that of the mother. (See p. 503 of this volume.) Again, examples have occurred in which the foetus has been extruded with the placenta and membranes entire.4 In a case of the kind that occurred to Wrisberg, the circulation continued for nine minutes; in one described by Osiander,5 for fifteen minutes; in some, by Professor Chapman, from ten to twenty minutes; and in one, by Professor Channing, of Boston, and Dr. Selby, of Tennessee, where 1 Mussey, in Amer. Journ. of the Med. Sciences for November, 1829. 2 Granville, Graphic Illustrations of Abortion, &c, p. xx., Lond., 1S34. 3 1'ivcis Elementaire, ii. 552. 4 Granville, op. cit., part x., London, 1834. 6 Annalen, B. i. S. 27. 582 FCETAL EXISTENCE. a bath of tepid water was used to resuscitate the foetus, for an hour,1 Marson2 and Flajani relate cases in which life continued for the same time: Dr. Nehr,3 of Rehau, in Bavaria, has recorded one in which the circulation of the child was unequivocal for seven hours after the sud- den and decided death of the mother; and others are referred to by D'Outrepont in his comments on this.4 In cases of a similar kind, where the child could scarcely breathe and was in danger of perishino-, the life of the placenta was maintained by keeping it in water of a temperature nearly equal to that of the body, and the child was saved. All these facts prove demonstratively, that the foetus carries on a circu- lation independently of that of the mother; and whatever passes between the foetal and maternal vessels is probably exhaled from the one and absorbed by the other, as the case may be. The fluid sent to the foetus is supposed by some—indeed by most—physiologists to be the maternal blood, modified or unmodified. Schreger,5 however, and others maintain, that the communication of any nutritious fluid from the mother to the foetus, and conversely, takes place by means of lymph- atics, and not by bloodvessels; and that the maternal vessels exhale into the spongy tissue of the placenta the serous part of the blood, which is taken up by the lymphatics of the fcetal portion, and conveyed into the thoracic duct. The views of Mr. Goodsir in regard to the absorbing tufts of foetal vessels have been given already, when describ- ing the placenta. It has been remarked before, that Lobstein6 and Meckel7 suppose, that the gelatinous substance of the cord is one of the materials of fcetal nutrition; which opinion they found on the circumstance of the albuminous nature of the substance, and the great size it gives to the cord at the early periods of fcetal life, as well as on the great develope- ment of the absorbent vessels of the foetus, which proceed from the umbilicus to the anterior mediastinum ;—and that others include, also, the fluids of the umbilical and allantoid vesicles. All these specula- tions regarding the various sources of nutritive matter, are sufficient evidence of the uncertainty that prevails on this interesting topic. It is manifest, however, that we cannot regard those substances to be nutritive to the foetus which are secreted by itself. It is impossible, that any developement can occur without the reception of materials from without. We have seen, that when the ovum passes from the ovarium to the uterus, it contains, within it, a molecule, and fluids destined doubtless for its nutrition, and which afford the necessary pabulum for the increase, that occurs between the period of impregna- tion and that at which an adhesion is formed between the ovum and the inner surface of the uterus. The mother, having provided the nutritive material in the ovum, she must continue to do so in the uterus ; and as soon as the vascular communication is formed between 1 Horner's Special and General Anatomy, 5th edit., ii. 277, Philad., 1839. 2 Lond. Med. Gazette, August, 1833. 3 Neue Zeitschrift fiir Geburtskunde, von Busch, D'Outrepont und Ritgen, Band. iv. Heft 1, S. 58, Berlin, 1836. 4 Ibid., S. 60. 5 De Functione Placentae Uterinae, Erlang., 1795. 6 Essai sur la Nutrition du Foetus, Strasbourg, 1812. 7 Handbuch, u. s. w., Jourdan and Breschet's translation, iii. 785, Paris, 1825. NUTRITION OF THE FCETUS. 583 the exterior of the ovum and the interior of the uterus, nutritive ele- ments are doubtless received by the embryo;—for otherwise it would perish from inanition. AY hat, then, it has been asked, can be the nature of these elements ? Do they consist of maternal blood, laid hold of by the foetus at this early period, when no circulatory system is apparent; or are bloodvessels distributed to the membranes of the ovum, to enable them to continue the secretion of a nutritive matter, similar to that which they took with them from the ovarium, and which must necessarily have had a maternal origin? Neither sup- position is probable ; yet there is great reason for the belief, that the liquor amnii is secreted from the interior of the uterus, and passes through the membranes of the ovum by imbibition. If we admit it to be, indeed, in any manner inservient to nutrition, its production must be extraneous to the body it has to nourish. These observations apply equally to the jelly of the umbilical cord, which probably passes through the membranous envelopes, and may consequently be regarded as a nutritive material derived from the parent. Both, it is true, might be secreted by the foetus from fluids furnished by1 the mother, and be placed in depot, as the fat is in after existence. Philosophical Anatomy, then, instructs us, that the placenta and umbilical cord are not indispensable to fcetal nutrition ; and compels us'to infer with Meckel1—one of the most eminent of modern ana- tomists and physiologists—that the human placenta may have no direct agency in embryotrophy. M. Cazeaux,2 indeed, maintains, that " the placental vascular apparatus does not contribute to the nutrition of the foetus." We are, therefore, necessarily driven to the conclusion, before stated,—that, in order for a foetus to be developed in utero, it is but necessary, that there shall be an absorbing surface, surrounded by a nutritive substance, that will admit of being absorbed. Now, the cutaneous envelope of the foetus—monstrous or natural—is such a surface, and the liquor amnii such a fluid; and after the placenta is formed, it may lend its aid. Its great function probably is to admit of the fcetal blood being shown to that circulating in the maternal vessels, so that some change may be effected in the former, which may better adapt it for serving as the pabulum, whence the secretions, from which the fcetal organs have to be elaborated, may be formed. According to Dr. Reid,3 the blood of the mother, contained in the placental sac already described, and the blood of the foetus contained in the umbilical vessels, can readily act and react on each other through the spongy and cellular walls of the placental vessels and the thin sac ensheathing them, in "the same manner as the blood in the bronchial vessels of aquatic animals is acted upon by the water in which they float. If we admit this, however, it is obvious, that the nutritive fluid, when received into the system, will have to be con- verted into blood by the action of the foetus, in a manner bearing some analogy to what occurs in the adult, or in the simplest of living beings in which the nutritive fluid is absorbed at the surface of the body. Of the mode in which such conversion is effected we are in the darkness 1 Op. citat. 2 Op. cit.; or translation by Dr. R. P. Thomas,.p. 216, Philadelphia, 1853. 3 Edinb. Med. and Surg. Journ., Jan., 1S41, p. 8. 584 F03TAL EXISTENCE. that envelopes all the mysterious processes which are esteemed organic and vital; but that the foetus is capable of effecting it we have irre- fragable proof in the oviparous animal, where there can be no com- munication, after the egg is laid, between the embryo and the parent. Yet we find it forming its own blood from the yolk that surrounds it and undergoing its full and regular developement from impulses seated in itself alone. Of those physiologists, who consider that the mother sends her blood to the placenta, to be taken up by the foetal vessels, all do not conceive that it is in a state adapted for the nutrition of the new being: some are of opinion, that the placenta, or the liver, or both, modify it, but in a manner which they do not attempt to explain. In favour of an action being exerted by the placenta, they state that it is clearly the organ which absorbs the fluid, and that every organ of absorption is neces- sarily one of elaboration;—a principle which we have elsewhere proved to be unfounded; and, moreover, that the blood conveyed to the foetus by the umbilical vein differs essentially in colour from that conveyed to it by the umbilical arteries, which, we shall see, is not the fact; and, if it were, could be accounted for more satisfactorily. In support of the view, that a second change is effected in the liver, they affirm, that a great part of the foetal blood ramifies in the substance of that organ before it reaches the heart; a part only going by the ductus venosus; and that the great size of the liver, during fcetal life, when its function of secreting bile can be but sparingly exerted, is in favour of this notion.1 The opinion, that some change is effected upon the blood in the liver, is certainly much more philosophical and probable than the belief of Haller, that the object of its passage through that organ is to deaden the force with which the mother projects the fluid into the fcetal ves- sels. We have seen, that it is extremely doubtful, whether she trans- mits any; and that if she does, the communication is very indirect. M. Geoffroy Saint-Hilaire2 appears to think, that the blood of the mother, which he conceives to be sent through the placenta to the foetus, is unfitted for fcetal life, before it has undergone certain modifi- cations. That, according to him, which leaves the placenta, proceeds in part to the liver, and the remainder to the heart. In the liver it forms the material of the biliary secretion, or at least of a fluid, which, when discharged into the intestines, irritates them, and provokes a copious secretion from the mucous or lining membrane. This mucus, according to M. Saint Hilaire, is always met with in the stomach and intestines of the foetus; and the presence of meconium, and of other excrementitious matters in the intestines, shows, that digestion must have taken place. This digestion he considers to be effected upon the mucus, secreted in the manner just mentioned; and, in support of its being inservient to sanguification, he affirms, that its quantitvis too great for the simple purpose of lubricating the parts; that mucus is the first stage of all organic compounds; that it predominates in all young beings; is the foundation of every organ ; is more capable of assimila- tion than any other substance, &c. But independently of the whole of 1 Velpeau, Traite de l'Art des Accouchemens ; or Meigs's translation, 2d edit., p. 224, Philad., 1838. 2 Philosophic Anatomique, Paris, 1818-22. NUTRITION OF THE F02TUS. 585 this view being entirely hypothetical, it cannot be esteemed probable, that the foetus is nourished by one of its own secretions. All secre- tions must be formed from blood. Blood must, therefore, pre-exist in the fcetal vessels, and the process, indicated by M. Saint-Hilaire, be unnecessary. The same objections equally apply to the views of Drs. Lee and Robinson referred to previously (p. 569). M. Denis made a comparative analysis of the blood of the mother and of the foetus. He found the latter richer in solid constituents and in blood-corpuscles. The two following analyses were by him—the one of the venous blood of the mother; the other of the placental blood as it flowed from an artery of the cord. The latter was of a brown red colour, smelt of the liquor amnii, and became of a brighter hue on exposure to the air. Water Solid residue Fibrin Albumen . Blood-corpuscles Peroxide of iron Phosphuretted fat Osmazome and cruorin Salts Venous blood of mother. 781-0 219-0 2-4 50-0 139-9 0-8 9-2 4-2 12.5 Blood of umbilical artery. 701-5 298-5 22 50-0 222-0 2-0 7-5 2-7 12-1' Allusion has already been made to the opinions of Schreger on foetal nutrition. These were developed in a letter, written by him, in 1799, to Sommering.2 He considers that all communication of nutri- tious matter between the mother and foetus takes place through lym- phatics which he has described as existing in considerable numbers in the placenta and umbilical cord. The red blood flowing in the mater- nal vessels is too highly charged with carbon, and with other hetero- geneous substances, he thinks, to serve for the nutrition of the fa?tus. Its serous part, which is purer and more oxygenized, is therefore alone exhaled. The uterine arteries pour this serum into the spongy texture of the placenta, whence it is taken up by the lymphatics of the foetal portion. These convey it along the umbilical cord to the thoracic duct, whence it passes into the left subclavian, vena cava superior, right auricle and ventricle, ductus arteriosus, and aorta; and, by the umbili- cal arteries, is returned to the placenta. In this course, it is mixed with the blood, and becomes itself converted into that fluid. AArhen it attains, the placenta, the blood is not poured into the cells of that organ to be transported to the mother, but passes into the umbilical vein, the radicles of which are continuous with the final ramifications of the umbilical arteries. Lateral pores, however, exist in the latter, which suffer fluids to escape, that cannot be elaborated by the foetus, or that require again to be submitted to the maternal organs, before they are fitted for its support. These fluids, according to Schreger, are not absorbed by the veins of the uterus, but by the lymphatics of that viscus, which are so apparent in the pregnant state, and have been 1 Simon, Animal Chemistry, by Day, Sydenham Society's edition, i. 238, London, 1845. 2 Epistol. ad S. Th. Sommering, De Functione Placentae Uterinse, Erlang., 1799. See, also, Richerand, op. cit., 13eme tdit., § ccvi. 586 FCETAL EXISTENCE. injected by Cruikshank, Meckel, &c. In his view, therefore, the con- version of the serous fluid into blood is chiefly effected in the lymphatic system; and it has been a favourite hypothesis with many physiolo- gists, that organs, regarding whose functions we are so profoundly ignorant, and whose developement is so much greater during intra- uterine than extra-uterine existence,—as the thymus, and thyroid glands, and the supra-renal capsules,—are, in some way, connected with the lymphosis or haematosis of the foetus. AYe have already referred to the conjectures, that these organs are diverticula for the blood of those parts the functions of which are not exerted until an after period of existence. M. Broussais1 makes the thyroid a diverticulum to the larynx; the thymus to the lungs, and the supra-renal capsules to the kidneys. Notwithstanding these ingenious speculations, our darkness, with regard to the true functions of these singular organs, is consider- able. To conclude.—The most plausible opinion we can form on this intri- cate subject is, that the mother secretes the substances, which are placed in contact with the foetus in a condition best adapted for its nutrition; that in this state they are received into the system, by absorption, as the chyle or the lymph is received in the adult,—undergoing modifica- tions, in their passage through the foetal placenta, as well as in every part of the system where the elements of the blood must escape for the formation of the various tissues. AYith regard to the precise nutritive functions executed in the fcetal state,—and as concerns 1. Digestion,—it is obvious, that this cannot take place to any extent, otherwise excrementitious matter would have to be thrown out, which, by entering the liquor amnii, would be fatal to its important functions, and probably to the very existence of the foetus. Yet that some diges- tion is effected is manifest from the presence of meconium in the in- testines, which is probably, in part, the excrementitious matter arising from the digestion of the mucous secretions of the alimentary canal. 2. Respiration, as accomplished by lungs, does not exist; and we have already seen, that the idea of the foetus possessing the kind of respiration of the aquatic animal is inadmissible. An analogous func- tion to the respiration of the adult, however, exists as respects the changes effected upon the blood. It is probable, that blood is sent to the placenta to be there aerated, as it is in the lungs in extra-uterine life. Such was the opinion of Sir Everard Home, of Girtanner, Stein,2 and we may say it is that of many of the most enlightened physiolo- gists of the day. The chief arguments brought forward in support of it are,—the absolute necessity for aeration to every living being, animal or vegetable; the no less necessity to the life of the foetus of a free circulation of blood along the umbilical cord to and from the placenta; and the analogy of birds, in which the umbilical vessels are inservient to respiration by receiving the external air through the pores of the 1 Commentaires des Propositions de Pathologie, &c, Paris, 1829, or Drs. Hays's and Griffith's translation, p. 214, Philad., 1832. 2 Meckel's Handbuch, u. s. w., Jourdan's and Breschet's French translation, iii. 793, Paris, 1825. RESPIRATION OF THE FOETUS. 587 shell, so that if the shell be greased, respiration is prevented, and the chick dies.1 The sensible evidences of these changes being accomplished by the placenta are not like those we possess regarding the aeration of the blood in its passage through the lungs of the adult, where the venous differs so essentially from the arterial blood. It is indeed asserted, in works of anatomy, that "the effete blood of the umbilical arteries becomes regenerated in the placenta, assumes a brighter hue, and is returned to the foetus by the umbilical vein;" but this is not in accord- ance with experiment and observation. Bichat2 made numerous dis- sections of young pigs whilst yet in utero, and uniformly found the blood of the arteries and veins presenting the same appearance, and re- sembling the venous blood of the mother. Not the slightest difference was observed between the blood of the aorta and that of the vena cava, or between that of the carotid artery and of the jugular vein. He made the same observations in three experiments of a similar kind on foetuses of the dog. He, also, frequently examined human foetuses that had died in utero, and always found the same uniformity between arte- rial and venous blood: hence he concludes, that there is no difference between them in the foetus, at least in appearance. Similar experi- ments by Autenrieth3 furnished like results. Dr. Granville, too, affirms, that he has never been able to detect the least difference between the arterio-umbilical and venous-umbilical blood in the many cases he has examined,4 and it is important to bear this fact in mind, inasmuch as the absence of such difference may be received as one of the evidences that a foetus has not respired. The apparent identity, however, be- tween the blood passing to the placenta by the umbilical arteries and that returning by the vein cannot be real. The slightest reflection will show, that they must differ; and such is the opinion, from observa- tion, of Messrs. Bostock,5 Jeffrey, and others.6 It is from the blood, carried by the umbilical vein and distributed over the body, that all the organs of the foetus have to derive the materials of their nutrition and developement; and being deprived of these materials, the fluid must necessarily be different in the umbilical arteries from what it is in the umbilical vein. The researches of more modern chemistry have not been directed to the fcetal blood, but M. Fourcroy7 analyzed it, and found it differ materially from the blood of the child that had respired. He asserts, that its colouring matter is darker, and seems to be more abundant; that it is destitute of fibrin and phosphoric salts, and is in- capable of becoming florid by exposure to the influence of atmospheric air. It has been found, too, that the corpuscles of foetal blood do not resemble those of the blood of the mother. The fact, however, of the 1 Varnishes of organic animal matters, as albumen, gelatin, &c, have no effect in preventing the transmission of air. See Towne, Guy's Hospital Reports, Oct., 1839, p. 385. 2 Anatomie Generale, ii. 344, Paris, 1818 ; and Recherches Physiologiques sur la Vie et la Mort, p. 190, Paris, 1806. 3 Dissertatio Sistens Experimenta circa Calorem Foetus et Sanguinem ipsius Insti- tute Tubing., 1799. 4 Graphic illustrations, &c, p. 20. 5 Op. citat. 6 Chapman, Philadelphia Journal of the Med. and Phys. Sciences, i. 10. 7 Annales de Chimie, vii. 1U5. 588 FfETAL EXISTENCE. similarity in appearance between the arterial and venous blood of the foetus is no evidence that respiration is not one of the fcetal functions, inasmuch as the same thing is observed in fishes. Under the head of Circulation it was remarked, that the coloration of the blood is perhaps of no farther importance than as indicating, that the vital change of aeration has taken place in the lungs. In this case, we have the vital change effected without any such coloration. Yet how, it may he asked, is the modification in the blood produced where no placenta and no umbilical cord exist; as well as in the cases before referred to in which the foetus continues alive for hours after the death of the mother ? And can we suppose that in such cases aeration is effected by the liquor amnii containing an unusual quantity of oxygen, as has been presumed by some physiologists ? AYe have before remarked, that Professor J. Miiller was unable to detect oxygen in the liquor amnii, and found that when fish were placed in it, they died as soon as in oil.1. These are embarrassing questions, more easily propounded than answered. By some, it has been presumed, that the liver, even in the adult, performs a function supplementary to that of the lungs; and the great size of the organ, in the foetus, has bee'n conceived to favour the idea, that it may separate carbon and other matters freely from the system, and in this way be depuratory; but the grounds for this presumption are not, we think, impregnable. 3. It is in the foetal circulation, that we observe the most striking peculiarities of intra-uterine existence. Of its condition at the very earliest periods, mention has been made already (page 535). The pri- mitive circulation is connected with the existence of the umbilical vesicle ; and, like it, is only of short duration. Its purpose is to con- vey materials of nutrition from the vesicle to the foetus by the omphalo- mesenteric vessels. In birds the vesicle remains until the full develope- ment of the new being,—the whole of its nutriment during incubation being furnished by the yolk. A different circulation is established when the communication be- tween the intestine and the umbilical vesicle ceases. The omphalo- mesenteric vessels,—reduced towards the end of the' first month to a single artery and vein,—become atrophied, and disappear with the vesicle. The intra-fcetal portion of the omphalo-mesenteric vein alone persists, and continuing to receive the venous blood of the intestines by the mesenteric vein, it forms, at a later period, the trunk of the vena porta. Before this time the allantoid vesicle (Figs. 476, 477) has been developed ; and a new circulation becomes established through it. The formation of the allantoid and the arrangement of its vessels have been described already.2 This arrangement is well seen in the following figures from Coste, which exhibit the circulation as it exists at the end of the first month, when the circulation by means of the umbilical vesicle is disappearing, and that by the allantoid vesicle is becoming established. The vessels of the allantoid are at first four in num- ber ; but when the vesicle has fulfilled its function, one of the veins becomes atrophied, so that two arteries and one vein remain. These persist until birth, and form the vessels of the umbilical cord (Fig. 504). 1 Op. cit., i. 305. 1 Page 562. CIRCULATION OF THE FCETUS. 589 Fig. 508. Fig. 509. Fig. 508.—Diagram of the Circulation in the Human Embryo and its Appendages, as seen in profile from the right side, at the commencement of the formation of the Placenta. Fig. 509.—The same, as seen from the front. a. Venous sinus, receiving all the systematic veins ; 6, right auricle; 6', left auricle ; c, right ventricle; c', left ventricle; d, bulbus aorticus, subdividing into e, e', e", branchial arches ; /, /', arterial trunks formed by their confluence ; g, g', vena azygos superior ; h, W, confluence of the superior and inferior azygos ; j, vena cava inferior ; k, k', vena azygos inferior ; to, descending aorta ; n, n, umbilical arteries proceeding from it; o', o, umbilical veins : q, omphalo-mesenteric vein ; r, omphalo-mesenteric artery, distributed on the walls of the vitelline vesicle t; v, ductus venosus ; y, vitelline duct; z, chorion. The mode in which the circulation is effected during the last months of fcetal existence is as follows. From the sketch already given of the circulatory organs of the mature foetus, it will be recollected,—1st. That the two auricles of the heart communicate by an aperture in the septum, called foramen ovale, which has a valve opening towards the left ventricle. 2dly. That near the orifice of the vena cava inferior is the valve of Eustachius, so situate as to direct the blood of the cava into the foramen ovale. 3dly. That the pulmonary artery has a vessel passing from it into the aorta,—the ductus arteriosus. 4thly. That two arteries, called umbilical, proceed from the internal iliacs to the umbilicus and placenta; and lastly, that the umbilical vein from the placenta pours part of its blood into the vena porta; and part passes by the ductus venosus, —a fcetal vessel,—into the inferior cava. The course of the circulation, then, is as follows. The blood of the umbilical vein,—the radicles of which communicate with those of the umbilical arteries in the placenta, —proceeds along the vein to the umbilicus, and thence to the liver. A part of this traverses the ductus venosus, enters the vena cava inferior, and becomes mixed writh the blood from the lower parts of the foetus; the remainder passes into the vena porta?, is distributed through the 590 FGETAL EXISTENCE. liver, and, by means of the hepatic veins, is poured into the vena cava. In this manner it retains the right auricle. Owing to the arrangement of the valve of Eustachius, the blood passes immediately through the foramen ovale into the left auricle,—without being mixed with that proceeding from the upper parts of the body into the right auricle through the vena cava superior. Tbe left auricle is consequently as much developed as the right, which it would scarcely be did it receive only the blood from the lungs. AArere it not as large, it is obvious that it would be insufficient to carry on the circulation when the whole of the blood passes through the lungs, and is poured into it, after respiration is established. Such are the opinions of AYolff and Sabatier1 regarding the use of the Eustachian valve. According to this view, if the valve did not exist, the aerated blood, conveyed to the heart by the ductus venosus instead of being directed into the left auricle through the foramen ovale, would pass into the right auricle, and thence, in part, at least, into the right ventricle; from which it would be transmitted through the pulmonary artery and ductus arteriosus into the descending aorta; so that no part of the body above the opening of the duct into the aorta could receive aerated blood, whilst much of that which passes along the aorta would be returned to the placenta by the umbilical arteries. But as the blood is directed into the left auricle by the Eustachian valve, it passes thence into the left ventricle, and by it is forced into the aorta, which distributes it to every part of the system, and thus conveys the regenerated fluid to every organ. Dr. AYistar3 suggested, that, without this arrangement of the Eustachian valve, the coronary arteries, distributed to the heart, would be unfit for support- ing the life of that organ, inasmuch as they would be deprived of a regular supply of revivified blood. From the left auricle, the blood passes into the left ventricle, and from the left ventricle into the ascending aorta, and to the upper parts of the body, from which it is brought back, by the vena cava superior, into the right auricle; thence it is transmitted into the right ventricle, and, by the contraction of the ventricle, into the pulmonary artery. By this vessel the greater part is sent through the ductus arteriosus into the descending aorta, and a small part to the lungs. Dr. Peaslee,3 however, thinks that owing to the small size of the duct it can serve no other purpose than that of a waste-pipe to carry off the blood, what they cannot receive. But little blood, however, goes to the lungs during intra-uterine existence. From the lungs, the blood is returned into the left auricle by the pul- monary veins. Through the descending aorta, the blood, conveyed in part by the ductus arteriosus, and in part by the contraction of the left ventricle, is distributed, partly to the lower extremities, from which it is returned by corresponding veins into the vena cava inferior, and partly by the umbilical arteries to the placenta. This view of the circulation supposes—what is disputed—that the blood of the vena cava superior and that of the Vena cava inferior do not 1 Traite Complet d'Anatomie, ii. 224, and iii. 3S7 ; and Memoir, de l'Academ. des Sciences pour 1744. 2 System of Anatomy, 3d edit., edited by Dr. Horner, ii. 76, Philad., 1823. 3 American Medical Monthly, May, 1854. CIRCULATION OF THE FG3TUS. 591 undergo admixture in the right auricle; whence it would follow that some parts of the body receive a purer blood than others,—the upper parts, as the head and neck, receiving that which flows immediately from the placenta, whilst the lower do not obtain it until it has circu- lated through the upper. Under any view it is manifest, that not the whole of the blood is distributed to the organ of aeration, as in the adult, but a part only, as in the batrachia. Bichat and Magendie1 contest the explanation of Wolff and Sabatier regarding the use of the valve of Eustachius and the non-admixture of the blood of the two cavae in the right auricle. In their opinion, the two bloods do commingle; but owing to the existence of the foramen ovale, and the arrangement of the valve of Eustachius the left auricle is filled simultaneously with the right; and, consequently, the same kind of blood must be distributed to both the upper and lower portions of the body. The uses of the foramen ovale and ductus arteriosus are explained as follows. As the left auricle receives but little blood from the lungs, it could furnish only a small quantity to the left ventricle, did it not receive blood through the foramen ovale; and, again, as the luno- is exerting no function during the state of fcetal life, the blood is sent along the pulmonary artery and ductus arteriosus into the aorta, so that the contraction of both ventricles is employed in propelling the blood along the aorta to the lower parts of the body and the placenta. AVithout this union of forces, it is conceived, the blood could not be urged as far as the placenta. Experiments by Dr. John Eeid2 favour the views of Wolff and Saba- tier. He took a foetus of about seven months, and threw simultane- ously a red-coloured injection up the vena cava inferior, and a yellow- coloured one down the vena cava superior. On tracing the red injec- tion upwards, it was found to have passed through the foramen ovale, and to have filled the left side of the heart, without any intermixture with the yellow, except very slightly at the posterior part of the right auricle. Not a drop of the yellow appeared to have accompanied the red to the left heart. From the left heart it ascended the aorta, and filled all the large vessels. going to the head and upper extremities. The injection, in all these vessels, had not the slightest tinge of yellow. On tracing the yellow injection downwards, he found it filling the right auricle and ventricle, whence it proceeded along the pulmonary artery, and filled the ductus arteriosus, and the branches proceeding to the lungs. On entering the aorta, it passed down that vessel, filling it completely without any admixture of red, so that all the branches of the thoracic and abdominal aorta were filled with the yellow. From this and other experiments of a similar kind Dr. Eeid infers, that the blood, returning from the placenta, passes principally to the head and upper extremities; and that the lower part of the body is chiefly sup- plied by blood returning by the vena cava superior; or, in other words, by blood that has already gone the circuit of the body. The observa- tions, however, of Dr. T. Williams3 have convinced him, notwithstand- ing the opposing experiments of Dr. Eeid, that the Eustachian valve 1 Pr.'cis Elementaire de Physiologie, 2de edit., ii. 550, Paris, 1825. 2 Edinb. Med. and Surg. Journ., xliii. 308. 3 London Med. Gaz., March 31, 1843. 592 FCETAL EXISTENCE. is mechanically inefficient in preserving the individuality of the two currents from the vena cava as they traverse the right auricle; and he affirms, that at the period of its diastole, when the auricle has attained a moderate distension, it may be readily demonstrated, that the two streams must intermingle freely. Hence, it is not true—he infers— that the difference of quality, between the blood distributed to the two portions of the body of the foetus is as great as is generally taught by anatomists. After all, the great difference between the adult and the fcetal cir- culation is,—that in the former, a part of the blood only proceeds to the organ of sanguification; that the aerated blood is poured into the right auricle instead of the left; that, instead of proceeding through the lungs, a part of the blood gets at once to the left side of the heart. whence it is sent to the head and upper extremities, and the remainder goes directly from the pulmonary artery into the aorta; and that a part of the aortic blood proceeds to the lower extremities, and the remainder goes to the placenta, from which it is returned into the inferior cava. 4. With regard to the nutrition, (properly so called,) of the foetus, it is doubtless effected in the same manner as in the adult; and our igno- rance of the precise nature of the mysterious process is equally great. During the whole of fcetal existence it is energetically exerted; and especially during the earlier periods. Sommering has asserted, that the growth of the foetus fluctuates; that it is greatest in the first month; in the second, less; in the third, greater; less, again, in the fourth; and again greater until the sixth, when it diminishes until birth. There is a singular circumstance connected with the nutrition of the foetus, that cannot be passed over without a slight notice, although, in its details, it belongs more properly to pathological anatomy. Owing to inappreciable causes, the different parts of the foetus, or some par- ticular part, may be preternaturally developed, or be defective, so as to give rise to anomalies of conformation, or what have been termed monstrosities,—vitia primoz conformationis. Three kinds of monsters may be considered to exist. The first comprises such as are born with an excess of parts, as with two heads to one trunk, two trunks to one head; with four arms and four legs; twins with a band uniting them, as in the case of the Siamese twins, &c. The second includes those in which parts are defective, as acephali, anencephali, &c.; and the third, \ those in which there is perversion of the formative process, so as to produce various modifications in the direction and situation of organs,— as where the heart is on the right side, the liver on the left, &c; in other wrords where there is transposition of the viscera. In these cases there is respective^—to use the language of the German pathologists —superabundant, defective, and perverted action of the force of forma- tion—the Bildungstrieb—to which we have more than once alluded. The hypotheses, that have been advanced to account for these forma- tions, as well as for those in which the parts are irregularly developed, may be reduced to three. First. The influence of the imagination of the mother on the foetus in utero. Secondly. Accidental changes ex- perienced by the foetus at some period of uterine existence; and MONSTROSITIES. 593 Thirdly. Some original defect or fusion of the germs. The first of these causes has been a subject of keen controversy amongst physio- logists at all periods. AYe have seen, that the mother transmits to the foetus materials for its nutrition; and that, to a certain extent, nutrition is influenced by the character of the materials transmitted; so that if these be not of good quality, or in due quantity, the foetus may be imperfectly nourished, and even perish. Any violent mental emotion may thus destroy the child, by modifying the quantity or quality of the nutritive matter sent to it. Small-pox, measles, and other contagious diseases can be unquestionably communicated to the foetus in utero; so that its life is indirectly but largely dependent upon the condition of the mother; and many striking examples of the influence of the mother on the constitution of her unborn babe are given by Dr. Combe.1 But the maternal influence has been con- ceived to extend much beyond this; and it has been affirmed, that her excited imagination may occasion an alteration in the form of particular parts of the foetus, so as to give rise to nozvi, and to all kinds of mother's marks, as they have been termed. These may. con- sist of spots resembling raspberries, grapes, &c; or there may be defective formation of particular parts,—and some of the cases that have been brought forward in favour of their having been induced by impressions, made upon the mother during pregnancy, are sufficiently striking. There are numerous difficulties, however, in the way of ac- cepting the cause assigned. If a child has been born with nasvi of any kind, the recollection of the mother is racked to discover whether some event did not befall her during gestation to which the appearance may be referred, and it is not often difficult to discover plausible means of explanation. Cases have occurred in which the mother, when a few months advanced in pregnancy, had been shocked by the sight of a person who had lost a hand, and the child has been born with the same defect. A young female, a few months gone with child, visited a brother in one of the hospitals of London, who was wounded in the side. His condition affected her extremely. Her child was born with a deep pit in the same part that was wounded in the brother. These are samples of the thousands of cases that have been recorded. Similar instances have been related of the inferior animals. In the extracts from the minute book of the Linnean Society of London, an ' account is given, by Mr. George Milne, F. L. S., of the effect of the imagination of a cat on her young. One afternoon, whilst Mr. Milne and his family were at tea, a young cat which had arrived at the middle of gestation, was lying on the hearth. A servant, by accident, trod very heavily on her tail; she screamed violently, and from the noise emitted, it was evident, that a considerable degree of terror was mingled with the feeling from the injury. From so common a cir- cumstance no extraordinary result was expected; but, at the full time, she dropped five kittens, only one of which was perfect: the other four had the tail remarkably distorted; and all in the same manner.2 1 Treatise on the Physiological and Moral Management of Infancy, Amer. edit., p. 67, Phila., 1840. 2 Fleming's Philosophy of Zoology, vol. i. p. 406, Edinb., 1S22. vol. ii.—88 (t 594 FCETAL EXISTENCE. Are we to consider these and similar cases of malformation or mon- strosity to be dependent upon the influence of the maternal imao-ina- tion on the foetus in utero ? Or are we to regard them as coincidences the cause being inappreciable, but such as gives occasion to vicious organization, where no coincidence with excited imagination can be discovered ? Under the head of Generation wre have shown the diffi- culty in believing, that the mother's fancy can have any effect—as to sex or likeness—during a fecundating copulation. Let us, then, in- quire what we have to admit in a case where a female is, we will sup- pose, four months advanced in pregnancy, when she is shocked at the appearance of one who has lost his arm, and the child is born with a like defect. It has been seen, that the communication between the mother and foetus is of the most indirect kind; that the circulation of the foetus is totally distinct from that of the mother; and that she can only influence the foetus through the nutritive material she furnishes, —whatever be its character,—and, consequently, that such influence must be exerted on the whole of the foetus, and not on any particular part. Yet, in the case we have assumed, the arm must have been already formed, and the influence of the mother's fancy have been ex- clusively exerted upon its absorbents, so as to cause them to take up that which had been deposited ! This assumed case is not environed with more difficulty than any of the kind. It is a fair specimen of the whole. Yet how impracticable to believe, that the effect can be connected with the assigned cause, and how much more easy to presume that the coincidence has been accidental. Cases of hare-lip are perpetually occurring, yet we never have the maternal imagination invoked as the cause; because it is by no means easy to discover a similitude between the affection and common extraneous objects. Moreover, in animals of all kinds—even in the most inferior, as well as in plants—monstrous formations are incessantly occurring where maternal imagination is out of the ques- tion. As a cause of monstrosity, therefore, its influence has been gene- rally regarded as an inadmissible hypothesis, and by many has been esteemed ridiculous; yet it manifestly receives favour with Sir Everard Home;1 and Professors Elliotson2 and Burdach3 appear inclined to favour it; but on the whole we are justified in adopting the opinion of Dr. Blundell, which has been embraced by Drs. Allen Thomson4 and AYagner,5 that it is contrary to experience, reason, and anatomy, to believe that the strong attention of the mother's mind to a determinate object or event can cause a determinate or specific impression upon the body of her child, without any force or violence from without; and that it is equally improbable, that, when the imagination is ope- rating, the application of the mother's hand to an}7 part of her own body, will cause a disfiguration or specific impression on a correspond- ing part of the body of the child. The third hypothesis, with regard to defective germs, has been canvassed under the head of Generation, 1 Philos. Transactions for 1825, and Lect. on Compar. Anat., v. 190, Lond., 1828. 2 Translation of Blumenbach's Physiology, 4th edit., p. 497, Lond., 182fc. 3 Die Physiologie als Erfahrungswissenschaft, B. ii. 4 Art. Generation, Cyclop, of Anat. and Physiol., P. xiii. p. 477, February, 183b. 5 Elements of Physiology, translated by Dr. Willis, p. 2-7. note, Lond., 1841. MONSTROSITIES. 595 and deemed insufficient. The second, consequently, alone remains, and is almost universally adopted. Independently of all disturbing influences from the mother, the foetus is known to be frequently attacked with spontaneous diseases, as dropsy, ulceration, gangrene, cutaneous eruptions, &c. Some of these affections occasionally destroy it before birth. At other times, it is born with them; and hence they are termed connate, or congenital. The following table, drawn up by Mr. AYilde1 from the records of the Gebaranstalt, of Vienna, ex- hibits the malformations observed in 23,413 births. Clubfoot, 16 cases, or once in 1463-31 Hare lip, 20 n u 1170-65 ------simple, 9 II n 2601-44 ivith clpft pulatp 11 11 u 2128-45 Spina bifida, 5 II ii 4682-6 Hydrocephalus, 6 n u 3902-16 Six lingers, 3 II u 7804-33 Imperforate anus, . 2 11 ii 11706-5 Hemicephalia, 1 11 ii 2.3413 Acephalia, 1 11 ii 23413 Umbilical hernia, . 1 11 u 23413 Without eyes, 2 11 ii 11706-5 Wanting superior part of vertex, 1 Ii ii 23413 Lenticular cataract, 1 II u 23413 Wanting one upper extremity, 2 II ii 11706-5 With plurality of fingers and toes, 5 11 u 4682-6 Hydrocephalus with spina bifida, and closed anus, 1 II i< 23413 Clubfoot and closed anus, 1 u n 23413 In a population, consequently, chiefly illegitimate, 88 deviations from the natural type occurred in 23,413 births, or about 1 in every 266 cases. Where a part has been wanting, the nerve, or bloodvessel, or both, proceeding to it, have likewise been found wanting; so that the defect of the organ has been thus explained; without our being able, how- ever, to account for the deficiency of such nerve or bloodvessel, which is the main point. In some cases of monstrosity, a fusion of two germs seems to have occurred. Two vesicles have been fecundated and subsequently com- mingled, so that children have been produced with two heads and one trunk, or with two trunks and one head, &c. ke. This is one mode of accounting for the whole class of monsters by excess, including those commonly called double monsters ; but it can scarcely be presumed, that the slighter cases of monstrosity by excess,—six fingered children, for example—are produced by the fusion of germs;—and, accordingly, Professor Arogel2 ascribes them to the "furcation" of a single germ," and Professor Vrolik3 is in favour of the view of excess or irregular distribution of developemental power, and prefers to regard those cases " as examples rather of singleness tending to duplicity than of duplicity tending to singleness;" and the reasons he assigns for this view, and for rejecting the hypothesis of fusion, are:—" that it is probable, that the whole class of monsters by excess owe their origin to different 1 Austria, &c, p. 224. Dublin, 1843. 2 The Pathological Anatomy of the Human Body, translated by Dr. Day, p. 509, Lond., 1847. 8 Art. Teratology, Cyclopedia of Anatomy and Physiology, iv. 976, Lond., 1852. 596 FCETAL EXISTENCE. degrees of one common fault, and, consequently, that the explanation of their origin ought to be the same for all;—that no kind of fusion can account for the production of supernumerary individual organs, the rest of the body being single; but that it is not impossible, that excess of power in the ovum, which, all admit, can alone explain the lower degrees of duplicity, may, in proportionally higher degrees, perhaps by the formation of two primitive grooves, produce the more complete double monsters, or even two such separate individuals as are sometimes found within a single amnion." Such, too, is the view embraced by, Eokitansky,1 and by Dr. Car- penter.2 " There is," says the latter, " another class of objects, to which tumours come into close relation, and which must be referred, like them, to a local excess of formative activity; these are the supernu- merary parts which are not unfrequently developed during fcetal life, as for example, additional fingers and toes. It seems absurd to refer these, formed, as they are, by simple outgrowth from the limbs to which they are attached, to the fusion of germs; which has been hypothetic cally invoked to explain more important excesses, as those of addi- tional limbs, double bodies or double heads; and yet, from the lower to the higher form of excess, the transition is so gradual, that what is true of the former can scarcely but be true of the latter. Hence even complete double monsters must be regarded, hot as having proceeded from two separate germs, which have become partially united in the course of their developement, but from a single germ, which being possessed of an unusual formative capacity has evolved itself into a structure containing more than the usual number of parts, and com- parable to that which may be artificially produced by partial fusion of the bodies of many of the lower animals. AVe can scarcely fail to recognize, throughout this whole series of abnormal productions, the operation of a similar power. In the formation of a supernumerary part, this has been sufficient, not merely to produce the tissues, and to develope them according to a regular morphological type, but to impart to the fabric, thus generated, a separate and even independent existence; thus evolving an additional finger or thumb on each hand, a double pair of arms or legs, a double head or trunk, or even a com- plete body." Yet although the view may seem to Dr. Carpenter to be "absurd," it certainly appears much more probable, that complete double mon- sters—the Siamese twins, for example—are evolved from two germs, than that they can arise from the increased formative action of one germ; whilst supernumerary parts—additional fingers and toes for example—may be properly referred to local excess of formative activity. Bischoff3 refers monstrosities with the number of parts in excess to various causes. First, to original formation of the germ. Secondly, 1 Manual of Pathological Anatomy, Sydenham Society's edition, i. 30, London, 1854. 2 Principles of Human Physiology, Amer. edit., by Dr. F. G. Smith, p. 340, Philad., 1855. 3 Art. Entwickelungsgeschichte mit besonderer Beriicksichtigung der Missbildungen, in Wagner's Handworterbuch der Physiologie, 6te Lieferung, S. 914, Braunschweig, 1843. SECRETIONS OF THE FCETUS. 597 to an tmcommonly energetic developement of an originally single germ, induced probably by external causes. Thirdly, to an ovum in ovo ; and fourthly, to arrest of developement, (as in the ossa AYormiana.) This interesting department of pathological anatomy has become, of late years, of moment as elucidating the normal formation of the ani- mal body, which appears to be effected—even in the production of anomalies—in accordance with a unity of organic composition, and with laws of developement but little appreciated until the present century, and still sufficiently obscure. The labours of Geoff'roy and Isidore Saint-Hilaire, Serres, Sommering, Meckel, Tiedemann, Beclard, Gurlt, Breschet, Allen Thomson, Vrolik, Rokitansky, and others, have—as Cuvier remarked of some of them—occasioned the accumulation of an infinity of facts and views, which, even if we do not admit all that their authors contend for, cannot fail to be of solid advantage to science. 5. That the fcetal secretions are actively formed is proved by the circumstance, that all the surfaces are lubricated nearly as they are afterwards. The follicular secretion is abundant, and at times enve- lopes the body with a layer of sebaceous matter—vernix caseosa—of considerable thickness. Vauquelin and Buniva1 have asserted, that this is a deposit from the albumen of the liquor amnii; but it is not found except on the body of the foetus. It is not on the placenta or umbilical cord, and is most abundant on those parts of the foetus, where the follicles are most numerous. Fat also exists in quantity after the fifth month. The greatest question has been in regard to the presence of certain secretions that are of an excrementitious character. For example,—by some, the urinary secretion is supposed to be in activity from the earliest period of intra-uterine existence, and its product to be discharged into the liquor amnii. Such is the opinion of Meckel.2 The circumstances that favour it, are,—the fact of the existence of the kidneys at a very early period; and that at the full time the bladder contains urine, which is evacuated soon after birth. On analysis, this is found to be less charged with urea and phosphoric salts than after- wards. A recent analysis exhibited it to be an albuminous fluid, free from sugar, containing some of the usual salts of the urine, abounding in a highly nitrogenized principle, probably allantoin; affording no urea, " and depositing a remarkably large amount of nucleated base- ment epithelium."3 Of the meconium we have already spoken (p. 568). It is manifestly an excretory substance, produced, probably, by the digestion of the fluids of the alimentary canal, mixed with bile. Some, indeed, are of opinion, that it is altogether a secretion from the liver, and intended to purify the blood sent by the mother, as to adapt it for the circulation of the foetus. Into the value of the theory on which this notion rests, we have inquired at some length. The notion itself scarcely requires further comment. 1 Annales de Chimie, torn, xxxiii.; and Memoir, de la Societe Medicale d'Emulation, iii. 229. 2 Handbuch, u. s. w.; or French translation hy Jourdan and Breschet, iii. 780 ; or the English translation by S. A. Doane, Philad., 1832. 3 W. Moore, Dublin Quarterly Journal of Med. Science, August, 1855 ; or Brit, and For. Med.-Chir. Rev., Jan., 1856, p. 233. 598 FCETAL EXISTENCE. 6. The animal temperature of the foetus cannot be rigorously deter- mined. The common belief is, that it is some degrees lower than that of the mother; and it is affirmed, that the temperature of the dead foetus is higher than that of the living. If such be the fact, it must possess means of refrigeration. M. Edwards found, in his experiments that the temperature of new-born animals is inferior to that of the adult; which is in accordance with the general belief regarding that of the foetus in utero. In some cases, as in those of the kitten, puppy, and rabbit, if the young be removed from the mother, and exposed to a temperature of between 50° and 70°, the temperature will sink,—as happens to the cold-blooded animal,—to nearly the same degree. He found the faculty of producing heat to be at its minimum at birth; but it progressively increased, until in about fifteen days the animal acquired the power in the same degree with the adult. This was not the case, however, with all the mammalia. It seemed to be confined to animals that are born blind; in which a state of imperfection probably exists in other functions. It was the same with birds as with mammalia: birds, hatched in a defective state, as regards their organs generally, have the power of producing heat defective; whilst others, born in a more per- fect condition, have the organs of calorification more capable of exer- cising their due functions. In a case in which the mother, who had borne five children, was confident that her period of gestation was less than 19 weeks, but probably from the length and weight of the foetus it was 25 weeks, the power of calorification of the latter was so low, that artificial heat was constantly needed to sustain it: under the influ- ence of the heat of the lire, however, it evidently became weaker, whilst the genial warmth of a person in bed rendered it lively and compara- tively strong.1 Opinions with regard to the temperature of the human infant vary. Haller2 asserts that it has less power of producing heat than the adult, and such is the opinion of MM. Despretz, Edwards,3 and the generality of physiologists. The latter gentleman estimated it at 94/25° of Fah- renheit. On the other hand, Dr. John Davy4 affirms, that the tempe- rature of young animals generally, and that of a new-born child, which he particularly examined, was higher than that of the adult. It is impossible to account for this discordance; but the general results of experiments would seem to agree with those of M. Edwards. Howso- ever this may be, the foetus certainly possesses the power of producing its own caloric ; otherwise its temperature should correspond with that of the mother, which, we have elsewhere seen, is not the fact. b. Animal Functions. The external senses in general are manifestly not in exercise during fcetal life: of this there can be no doubt, as regards the sense of sight; and the same thing probably applies to taste, smell and hearing. With regard to tact, however, we have the best reason for believing, that it exists, particularly towards the latter periods of utero-gestation. 1 Edinb. Medical and Surgical Journal, vol. xi. 2 Element. Physiol., vi. 3. 3 De l'lnfluence des Agens Physiques, Paris, 1824. 4 Philos. Transact, for 1814, p. (iU2. ANIMAL FUNCTIONS. 599 Either in a senso-motory or reflex manner, the cold hand, applied over the abdomen of the mother, instantly elicits the motions of the child - The brain and nervous system of the foetus must, therefore, have undergone the developement necessary for the reception of tactile impressions made through the medium of the mother; for conveying such impression to the percipient organ, and accomplishing perception. The existence of internal sensations or wants would be supereroga- tory in the foetal state, where the functions, to which they minister after birth, are themselves wanting. It is probable, that there is no digestion except of the mucous secretions of the tube; little or no excretion of fasces or urine; and certainly there is no pulmonary respi- ration. It is not unlikely, however, that internal impressions, origi- natino* in the very tissue of the organs, may be communicated to, and appreciated by, the encephalon. AVe have strong reason for believing, that pain may be experienced by the foetus; for if it be destroyed by any sudden influence in the later periods of pregnancy, death is gene- rally preceded by irregular movements manifest to the mother, and frequently leading her to anticipate the result. M. Adelon asks, whether it may not be affected, under such circumstances, with convulsions, similar to those that animals experience when they die suddenly, espe- cially from hemorrhage ? It is impossible to reply positively to the question; but that the child suffers appears evident. The most elevated of the functions of relation—the mental and moral faculties—would seem to be needless in the foetus; and consequently can be little, if at all, exercised. MAI. Bichat and Adelon,1 consider- ing that its existence is purely vegetative, are of opinion that they are not exerted. M. Cabanis,2 however, suggests, that imperfect essays may, at this early period, be made by virtue of the same mstmct that impels animals to exercise their organs prior to the period at which they are able to derive service from them; as in the case of the bird, which shakes its wings before they are covered with feathers. It is difficult to deny to the foetus all intellectual and moral manifestations. They must, doubtless, be obscurely rudimental; still, we may conceive that some may exist, if we admit that the brain is in a state for the perception of impressions; that tact is practicable, and instinct in activity. We find, moreover,—that the power of motion, voluntary as well as involuntary, exists after the fifth month, and probably much earlier, could it be appreciated. During the latter months of utero- gestation, the motion appears to be almost incessant, and can be dis- tinctly felt by placing the hand upon the abdomen. At times, indeed, it is manifest to the sight. The cause of these movements is by no means clear. It is probable, that they are instituted for the purpose of changing the position, which may have become irksome; for we have already remarked, that the foetus readily appreciates any sudden succussion given to it through the mother, and hence that it possesses tact, and, as we can readily understand, may experience fatigue from the maintenance of an inconvenient posture, and send nervous influ- ence to the appropriate muscles to change it. Dr. Simpson3 main- 1 Fhysiologie de l'Homme, 2de edit., iv. 420, Paris, 1829. 2 Rapport du Physique et du Moral de l'Homme, Paris, 1602. 3 Edinb. Monthly Journal of Science, July, 1849. 600 FCETAL EXISTENCE. tains, that the motions are altogether excito-motory; and that the posi- tion of the foetus in utero, or—as he expresses it—"the adaptive posi- tion of the contained to the containing body is the aggregate result of reflex movements on the part of the foetus by which it keeps its cuta- neous surface as far as possible from causes of irritation." All this proves, that the encephalic and spinal functions are exerted; but only for a few definite objects. The function of expression is almost, if not entirely, null in the foetus. There are cases on record, where children are said to have cried in utero, so as to have been heard distinctly, not only by the mother, but by those around her. Indeed, the objection, that an infant may respire before it is born, and yet not come into the world alive,—in which case there will be buoyancy and dilatation of the lungs,—has been brought forward against the docimasia pulmonum or lung-proof of infanticide. It is impossible for us to consider the cases of the kind that have been recorded as mere fabrications, or the phenomenon to be impossible,—except, indeed, whilst the membranes are in a state of integrity. AVhen they have given away, and the child's mouth presents towards the os-uteri, breathing and vagitus may be practicable; yet very positive and unexceptionable testimony is required to establish such an occurrence.1 c. Functions of Reproduction. These require no consideration. They are inactive during the fcetal state, except that the testicles secrete a fluid which is not sperm, and is found in the vesiculae seminales. A milky fluid is secreted by the breasts of infants, which has been examined by Guillot and Schloss- berger,2 and found to possess the characters of the milk of the mother, separating into a serous and a creamy portion. It would appear, as before remarked, that ovarian vesicles are already existent in intra-uterine life. 1 Taylor, Medical Jurisprudence, 3d Amer. edit., by Dr. Edward Hartshome, p. 390, Philad., 1853. 2 Cited by Dr. Day in Brit, and For. Med.-Chir. Rev., July, 1855., p. 220. AGES—FIRST PERIOD OF INFANCY. 601 BOOK IV. CHAPTER I. AGES. Under this head we have to include the modifications that occur in the functions from birth until dissolution. The different ages may be separated as follows:—infancy, comprising the period from birth until the second dentition;—childhood, that between the second dentition and puberty;—adolescence, that between puberty and manhood;— virility, that between youth and old age;—and old age. The details of the phenomena in each can only be regarded as the general appli- cation ;—the exceptions being frequently numerous and remarkable, especially in the later periods of existence. 1. INFANCY. The age of infancy extends from birth to the second dentition, or until about the seventh or eighth year: M. Flourens1 extends it to ten years. By M. Halle, and after him by MM. Renauldin,2 Rullier,3 Ade- lon,4 and others, this has been subdivided into three periods, which are somewhat distinct from each other, and may therefore be adopted with advantage. The one comprises the period between birth and the first dentition,—generally about seven months; a second embraces the whole period of the first dentition, or up to about two years; and the third includes the interval that separates the first from the second dentition. a. First Period of Lnfancy. As soon as the child is ushered into the world, it assumes an inde- pendent existence, and a series of changes occurs in its functions of the most sudden and surprising character. Respiration becomes established, after the manner in which it is to be effected during the remainder of existence; and the whole of the peculiarities of foetal circulation cease. The first act after the child is extruded is to breathe, and at the same time to cry. What are the agencies, then, by which the first inspira- tion is effected, and the disagreeable impression made? This haa been an interesting topic of inquiry amongst physiologists. A few of the hypotheses that have been indulged will be sufficient to exhibit the directions which the investigation has taken. 1 De la Longevite Humaine et de la Quantite de Vie sur le Globe, 2de edit., p. 46, Paris, 1855. 2 Art. Age, Dictionnaire des Sciences Medicales. 3 Art. Age, Diet, de Medecine, i. 3S1, Paris, 1821. 4 Physiologie de l'llomme, 2de edit., iv. 425, Paris, 1829. 602 AGES. Whytt,1—whose views were long popular, and still have supporters —conceived, that before birth the blood of the foetus is properly pre- pared by the mother; and when, after birth, it no longer receives the necessary supply, an uneasy sensation is experienced in the chest which may be looked upon as the appetite for breathing, in the same manner as hunger and thirst are appetites for meat and drink. To satisfy this appetite, the brain excites the expansion of the chest to prevent the fatal effects, that would ensue if the lungs were not im- mediately aroused to action. This appetite is supposed to commence at birth, owing to the circulation being quickened by the struggles of the foetus, and to an additional quantity of blood passing through the lungs, which excites them to action, and seems to be the immediate cause of the appetite. Haller2 ascribes the first inspiration to the habit, which the foetus has acquired, whilst in the uterus, of taking into the mouth a portion of the liquor amnii; and he supposes, that it still con- tinues to open its mouth, after leaving the mother, in search of its accustomed food. The air, consequently, rushes into the lungs, and expands them; the blood is distributed through them, and a regular supply of fresh air is needed to prevent it from stagnating in its passage from the right to the left side of the heart. Dr. Wilson Philip3 regards the muscles of inspiration as entirely under the control of the will; and he thinks, that they are thrown into action by the uneasy sensation experienced by the infant, when separated from the mother, and having no longer the necessary changes produced upon its blood by her organs. M. Adelon thinks it probable, that the series of developements occur- ring during gestation predisposes to the establishment of respiration. According to him, the lungs gradually increase in size during the latter months; the branches of the pulmonary vessels become enlarged, and the ductus arteriosus diminished; so that the lungs are prepared for the new function they have to execute. In addition to these altera- tions, he conceives that the process of accouchement predisposes to the change; that, by the contractions of the uterus, the circulation of the blood must necessarily be modified in the placenta, and, conse- quently, in the foetus;—for he is a believer in the doctrine, that the foetus receives blood from the mother by the placenta. Owing to this disturbance in the circulation, more blood is sent to the lungs; and when the child is born, it is subjected to new and probably painful impressions. " For instance," he remarks, " the external air, by its coldness and weight, must cause a disagreeable impression on the skin of the infant, as well as on the origin of all the mucous membranes; and, perhaps, the organs of the senses being, at the same time, suddenly subjected to the contact of their proper irritants, receive painful im- pressions from them. These different impressions being transmitted to the brain, are reflected to the different dependencies of the nervous system, and, consequently, to the nerves of the inspiratory muscles; these muscles, thus excited, enter into contraction, in the same manner as the heart is stimulated to renew its contractions during syncope; when a stimulating vapour is inspired." 1 An Essay on the Vital and other Involuntary Motions of Animals, Sect. ix. 109, Edinb., 1751. 2 Elem. Physiol., viii. 5, 2. 3 Quarterly Journal of Science, &c, vol. xiv. 100. FIRST PERIOD OF INFANCY—FIRST RESPIRATION. 603 The view taken by Dr. Bostock1 explains the process, as far perhaps as is practicable, on mechanical principles. The first respiratory act, according to him, seems to be purely mechanical, and to result from the change of position which the child undergoes at birth. From the mode in which it rests in utero, every thing is done that position can accomplish to diminish the dimensions of the chest; and any change in this position must have the effect of liberating the lungs from a portion of the pressure which they sustain. The head cannot be raised from the breast, nor the knees removed from the abdomen, without straightening the spine; and the spine cannot be reduced to a straight line without elevating the ribs and permitting the abdominal viscera to fall; but the ribs cannot rise nor the diaphragm descend, without enlarging the chest; and, as the chest enlarges, the lungs, which are the most elastic organs of the body, expand their air-cells, hitherto collapsed by external pressure, and the external air rushes in. The same cause is considered to account for the new circulatory movement. The blood, which, in the foetus, had passed through the foramen ovale and ductus arteriosus without visiting the lungs, is solicited from its course by the expansion of the chest, which draws the blood through the pulmonary artery as forcibly as it does air through the windpipe. The blood, thus exposed to the air in the lungs, becomes arterialized; and, from this moment, the distinction between arterial and venous blood is established. The circulation through the vessels peculiar to the foetal condition now ceases, even without any ligature being placed upon the umbilical cord. On the whole, the view of AYhytt, with the additions suggested by Dr. Marshall Hall, affords, perhaps, the best explanation of the pheno- mena. It has been elsewhere shown, that the function of respiration is partly voluntary and partly involuntary; partly, in other words, under the cerebro-spinal, and partly under the reflex system of nerves. AYhen the besoin de respirer or appetite for air becomes irresistible, the reflex or true spinal system acts predominantly, and the muscles con- cerned in the mechanical phenomena of respiration are immediately thrown into appropriate action. The act of impression in this "want" or internal sensation is probably in the new condition of the pulmo- nary bloodvessels, which at birth receive a sudden and large supply of blood. From them the excitor influence is conveyed to the centre of the reflex or excito-motory system. The sudden and important changes supervening in this manner guide us to the decision of an interesting medico-legal inquiry,— whether in a case of alleged infanticide, the child has respired or not; —in other words, whether it was born alive or dead ? After respira- tion has been established, the lungs, from being dark-coloured and dense, become of a florid red hue; are light and spongy, and float on water: on cutting into them, the escape of air from the air-cells occa- sions a crepitus, and a bloody fluid exudes; there is an approach to closure of the foramen ovale; the ductus arteriosus is empty, as well as the ductus venosus ; and the absolute weight of the lungs may be doubled. 1 Elementary System of Physiology, 3d edit., p. 323, Lond., 1836. 601 AGES. The different conditions of the organs of circulation, of the cord and skin, at different periods, beginning at the first and ending with the thirty-fifth day, have been summed up as follows by M. Dever- gie,1 from the result of numerous and careful observations. They may enable us to judge approximately of the age of the young infant, in questions of a medico-legal character. On the first day. Cord be- ginning to wither. Foramen ovale, ductus arteriosus, ductus venosus, and umbilical vessels open. Second day. AVithering of the cord com- plete. Foramen ovale closed in two out of eleven cases; partially closed in one out of seven. Ductus arteriosus beginning to close. Umbilical arteries obliterated to a greater or less extent. Umbilical veins and ductus venosus still open. Third day. Desiccation of the cord. Foramen ovale sometimes closed. Ductus arteriosus oblite- rated in one in eleven cases. Umbilical arteries very often obliterated. Umbilical vein and ductus venosus still open. Fourth day. Cord be- ginning to fall off. Foramen ovale closed in about one-third of the cases. Ductus arteriosus still open in the majority of cases. Umbi- lical arteries closed, but sometimes open near the iliacs. Umbilical vein and ductus venosus much contracted. Fifth day. Separation of the cord with rare exceptions. Foramen ovale closed in more than half the cases. Ductus arteriosus closed in about half the cases. Um- bilical vessels closed; vein occasionally open. Separation of the cuticle advanced. Eighth day. Entire separation of the cord, with commencing cicatrization. Foramen ovale closed in three-fourths of the cases. Ductus arteriosus completely obliterated in half the cases. Umbilical vessels closed. Ninth to eleventh day. Cicatrization of the umbilicus often complete; sometimes, however, there is an oozing of mucous matter from the cord for many days, so that the cicatrix ia retarded. Separation of the cuticle on the trunk, chest, and abdomen, and at the articulations. Twentieth to twenty-sixth day. Separation of the greater part of the cuticle. Thirtieth to thirty-fifth day. Separation of the entire cuticle, excepting that of the hands and feet, "which is often delayed until the fortieth day.2 Respiration having been once thoroughly established, the individual enters upon the first period of infancy, which has now to engage atten- tion. The animal functions, during this period, undergo considerable developement. The sense of tact is little evinced, but it exists, as the child appears very sensible to external cold. At first, touch is not exerted under the influence of volition; but, towards the termination of the period, it begins to be active. Taste is almost always null at first. M. Adelon3 thinks, that it is probably exerted on the first day as regards the fluids, which the infant sucks and drinks. AVe have daily evidence, however, that at an early period of existence, the most nauseous substances, provided they are not irritating, are swallowed indiscriminately, and without the slightest repugnance; but, before the termination of the period under consideration, the taste becomes inconveniently acute, so that the exhibition of nauseous substances, as of medicine, is a matter of more difficulty. Smell is probably more 1 Medecine Legale, 2de gdit., i. 552, Paris, 1840. 2 Guy, Principles of Forensic Medicine, Part i. p. 149, Lond., 1843. 3 Physiologie de l'Homme, edit, cit., iv. 433. FIRST PERIOD OF INFANCY. 605 backward than any of the other senses,—the developement of its organ bein°* more tardy, the nose small, and the nasal sinuses not in exist- ence. In the first few weeks, sight and hearing are imperfectly ex- erted, but, subsequently, they are in full activity. The internal sen- sations, being instinctive, exist; all those at least that are connected with the animal and nutritive, functions. Hunger and thirst appear during the first day of existence; the desire of passing the urine and fasces is doubtless present, notwithstanding they appear to be dis- charged involuntarily; and the morbid sensation of pain is often ex- perienced, especially in the intestinal canal, owing to flatus, acidity, &c. During the first part of the period, the child exhibits no mental and moral manifestations; but, in the course of a few weeks, it begins to notice surrounding objects, especially such as are brilliant; and to distinguish between the faces to which it has been accustomed and those of strangers;—awarding a smile of recognition or of satisfaction to the former, a look of gravity and doubt to the latter. Locomotion, as well as the erect attitude, is, at this time, utterly impracticable. The muscular system is not yet sufficiently developed; the spinous processes of the vertebrae are not formed, and it has not learned to keep the centre of gravity—or rather the vertical line—within the base of sustentation. The function of expression, at the early part of the period, is confined to vagitus or squalling, which indicates the ex- istence of uneasiness of some kind; but, before the termination of the period, the infant unites smiles and even laughter to the opposite expressions, and attempts to utter sounds, which cannot yet be con- sidered as any effort at conventional language. Sleep is largely indulged. Soon after birth, it is almost constant, except when the child is taking nutriment. Gradually, the waking intervals are pro- longed; but, throughout, much sleep is needed, owing to the frail condition of the nervous system, which "is soon exhausted by even feeble exertion, and requires intermission of action. After birth, the child has to subsist upon a different aliment from that with which it was supplied whilst in the womb. Its digestion, therefore, undergoes modification. The nutriment is now the milk of the parent, or some analogous liquid, which is sucked in, in the manner described under Digestion. For this kind of prehension the mouth is well adapted. The tongue is large, compared with the size of the body, and the want of teeth enables the lips to be extended forward, and embrace the nipple more accurately and conveniently. The action of sucking is doubtless as instinctive as the appetite for nutriment, and equally incapable of explanation. The appetite appears to be almost incessant, partly owing to the rapidity of growth, which demands con- tinual supplies of nutriment; and partly, perhaps, to a feeling of pleasure experienced in the act, which is generally the prelude to a recurrence of sleep, broken in upon apparently for the mere purpose of supplying the wants of the system, or the artificial desire produced by frequent indulgence. Often, we have the strongest reason for believing, that the great frequency of the calls of the appetite is occa- sioned by the habit, with many mothers, of putting the child constantly to the breast; inasmuch as in children that have been trained, from an early period, to receive the nutriment at fixed hours only, the desire may 606 AGES. not recur or be urgent until the lapse of the accustomed interval. Digestion at this age, is speedily accomplished;—the evacuations bem r@* fg^ Schemes of Sections of the Lower Jaw of the Foetus at different periods, to show the stages of developement of the sac of a temporary incisor and of the succeeding permanent tooth from the mucous membrane of the jaw. 1. The dental groove is formed in the mucous membrane. 2. The groove widens, and has a papilla at the bottom: this is the papillary stage. 3, 4, and 5 represent the follicular stage; the lips of the groove enlarge, and form a sunken follicle, in which the papilla, now enlarged and beginning to acquire the form of the future tooth-pulp, is hid. Membranous opercula, or laminae, are formed from the sides of the fol- licle, and, as seen in 5, meet over, leaving a lunated depression behind. The diagram, 5, supposing the opercula to be gently opened out, may be taken to represent a cross section through an incisor follicle 6. The lips of the groove also meet, except the lunated depression. 7. The opercula and lips of the groove cohere ; the follicle becomes a closed sac («); the papilla is the tooth-pulp (p), and has the shape of the crown of the future tooth ; and the lunated depression becomes a cavity of reserve for the developement of the succedaneous permanent tooth: the saccular stage is now complete. The remaining figures, 8 to 12, show the commencement of the cap of the dentine on the pulp, the subsequent steps in the formation of the milk tooth, and its eruption through the gum (11) ; also the gradual changes in the cavity of reserve, the appearance of its laminae and papilla, its closure to form the sac of the permanent tooth, its descent into the jaw, behind and below the milk-tooth, and the long pedicle (12) formed by its upper obliterated por- tion. the pulp. About the termination of the third month, ossification begins, and a little sooner in the lower than in the upper jaw. This consists, at first, of a deposition of ivory matter on the surface of the pulp and at its top, which goes on increasing in width until it covers the whole of the dental pulp with a shell. It augments, also, in thick- ness at the expense of the dental pulp, which becomes gradually less and less. When the bony shell has extended as far as the neck of the tooth, the external membrane or sac of the tooth—for the follicle con- sists of two membranes—attaches itself closely, but not by adhesion, to the part. The inner membrane becomes much more vascular, and the enamel is secreted by it. A thickish fluid is observed to be poured out from the inner surface, which is soon consolidated into a dark, chalky substance, and afterwards becomes white and hard. At birth, the coronae of the incisors are formed; those of the canine are not com- pleted ; and the molares have only their tubercles. The root or fang is formed last of all. As ossification proceeds, the corona of the tooth presses upon the gum, a portion of the follicle being interposed, which, as well as the gum, is gradually absorbed and the tooth issues. SECOND PERIOD OF INFANCY—FIEST DENTITION. 609 The age at which the teeth make their appearance varies. The fol- lowing table of the average periods, as stated by some of the principal writers on dental surgery, is given by Mr. Tomes.1 Authors. Central Incisors. Months. Lateral Incisors. Canines. Months. Months. 1st Molar. Months. 2d Molar. Months. Fox, 6,7,8 Extreme cases. 7, 8, or 9 17 to 18 14 to 16 24 to 30 Hunter, Bell, Ashburner, 4 to 13 7,8,9 5 to 8 7th, lower jaw 8th, upper jaw 7, 8, or 9 20 to 24 7 to 10 14 to 20 9th, upper jaw 16, 17,18 10th, lower teeth 19 or 20 20 to 24 12 to 16 20 to 24 18 to 36 Order of the First Dentition. Authors. Incisors. Canines. Central. Lateral. Molares. First. Second. Sir R. Croft, j \ { 2 Dr. Ashburner, -J , 3 4 4 3 7 8 6 7 5 6 5 5 9 10 8 8 Upper jaw. Lower jaw. Upper jaw. Lower jaw. Occasionally, chil- dren ha ve been born with teeth, whilst in other cases they have not pierced the gum until after the period we are considering. Gene- rally, the middle in- cisors of the lower jaw appear about the seventh month, and subsequently those of the upper; next the superior and inferior lateral incisors in succes- sion ; then the first lower molares, and first upper; next the inferior and su- perior canine teeth, successively : and lastly, the second molares of each jaw. As a general rule, the teeth of the lower jaw precede those of the upper: the lateral incisors are, however, an exception—those of Fig. 511. Front View of the Temporary Teeth. Fig. 512. The separate Temporary Teeth of each Jaw. Central incisor. b. Lateral incisor. c. Canine, d. First molaris. e. Second molaris. 1 A Course of Lectures on Dental Physiology and Surgery, p. 110, Lond., 1848. VOL. II.—3d 610 AGES. the upper jaw making their appearance, in the majority of cases, before those of the lower. When the tooth passes through the dental cap- sule and integuments, the child is said to have " cut a tooth;" it would seem, however, to be a process of absorption rather than of disruption, as Mr. A. Nasmyth has suggested.1 The subject of the intimate anatomy and developement of the teeth has been investigated of late years by many Fig. 513. observers, whose contributions are well worthy of study. Amongst the most important are those of Friinkel, Raschkow, Retzius, Arnold, Goodsir,2 Owen, Nasmyth3 and Tomes; and an able writer—Mr. Paget4—has remarked, that in no organs have the results of recent microscopic researches been so unexpected or brilliant. These researches have shown the teeth to be composed of three main constituents. 1. The crusta petrosa, cementum or cortical substance, which differs in ita minute structure in no respect from common osseous tissue. It forms the outermost layer of the teeth; visibly surrounds the whole fang, and extends, according to Mr. Nasmyth, in a very thin layer over the enamel of the crown. 2. The enamel, or adamantine substance which invests only the crown of the teeth, and is composed of solid prisms or fibres about ^g^o^h of an inch in thickness, set side by side upright on the ivory; and, 3. The dentine or ivory, which forms the chief mass and body of the teeth, and is com- posed of a fibrous basis, traversed by very fine, branching, cylindrical tubuli, which run in an undulating course from the pulp cavity, on the Vertical section of an Adult interior of which they open, towards the adjacent part of the exterior of the tooth. The basis of the intertubular substance, according to Henle, i i ivory of the tooth, in is composed of bundles of flat, pale, granular ^i%UTurei%fewen fibres, the course of which is parallel to that of as the position of the main the tubules. Mr. Nasmyth,5 however, states, as the result of his observations, that the so-called tubule is, in reality, a solid fibre, composed of a series of little masses succeeding each other in a linear direction, like so many beads collected on a string. Dentition is necessarily a physiological pro- cess, but it is apt to be a cause of numerous dis- eases. The whole period of its continuance is one of great nervous Bicuspis, cut from with- out inwards; greatly magnified. tubes. At the apex of the tooth the tubes are almost perpendicular. 2. Cavity of the pulp, in which are seen, by means of the glass, the openings of the tubes of the dental bone. 3, 3. Cortical substance which surrounds the root up to the commence- ment of the enamel. 4, 4. Enamel. 1 Medico-Chirurg. Transactions, vol. xxii., and Op., infra cit., p. 113, Lond., 1849. 2 Edinb. Med. and Surg. Journ., Ii. 3 Researches upon the Developement and Structure of the Teeth, London, 1839 and 1841; and Mr. Robert Nasmyth, in Lond. and Edinb. Monthly Journ. of Med. Sci. Jan., 1843, p. 40. 4 British and Foreign Medical Review, July, 1842, p. 270. 5 Op. cit., p. 113, Lond., 1849. SECOND PERIOD OF INFANCY—FIRST DENTITION. 611 Figs. 514 and 515. View of an Incisor and of a Molar Tooth, given by a Longitudinal Section, showing that the Enamel is striated and that the Striae are •all turned to the Centre. The in- ternal Structure is also seen. l._Enamel. pulpi. 2. Ivory. 3. Cavitas susceptibility,—so that the surgeon never operates during it, unless when compelled; and we can understand, that the pressure exerted by the tooth on the gum, and the consequent inflammation and irrita- tion, may lay the foundation for numerous diseases. More are doubt- less ascribed to the process than it is enti- tled to, but still they are sufficiently nume- rous ; and all require in their management the free division of the distended gum, so as to set the presenting part of the tooth at liberty. Whilst the teeth are appear- in"*, the muscular structure of the body is acquiring strength, and the salivary organs are described by anatomists as becoming much more developed. The food of the child is now diversified, and it begins to participate in the ordinary diet of the table. The excrementitious matters are conse- quently altered in character, particularly the alvine, which become firmer, and ac- quire the ordinary faecal smell; the urea is still, however, in the generality of cases, in less proportion than in the adult. The other functions require no special mention. The number of deaths, during this pe- riod, is great. The bills of mortality of London, as has been elsewhere remarked, show, that the deaths, un- der two years of age, are nearly thirty per cent, of the whole num- ber. In Philadelphia, during a period of twenty years ending with 1826, the proportion was rather less than a third. The cholera of in- fants is the great scourge of our cities during the summer months, whilst in country situations it is comparatively rare; and it is always found to prevail most in crowded alleys, and in the filthiest and im- purest habitations. There is something in the confined and deterio- rated atmosphere of a town, which seems to act in a manner directly unfavourable to human life, and to the life of the young especially; and this applies also to the animal. Experiments were instituted by Dr. Jenner, and since by Dr. Baron,1 which show that privation of free air and natural nourishment has a tendency to produce disorgani- zation and death. Dr. Baron placed a family of young rabbits in a confined situation, and fed them with coarse green food, such as cab- bage and grass. They were perfectly healthy when put up. In about a month, one of them died,—the primary step of disorganization being evinced by a number of transparent vesicles on the external surface of the liver. In another, which died nine days after, the disease had ad- vanced to the formation of tubercles in the liver. The liver of a third, which died four days later, had nearly lost its true structure, so com- pletely was it pervaded by tubercles. Two days afterwards, a fourth died; a number of hydatids was attached to the lower surface of the liver. At this time, Dr. Baron removed three young rabbits from the 1 Delineations of the Origin and Progress of Various Changes of Structure which oc- cur in Man, and some of the Inferior Animals, Lond., 1S2S. 612 AGES. place where their companions had died to another situation, dry and clean, and to their proper accustomed food. The lives of these were obviously saved by the change. He obtained similar results from ex- periments of the same nature performed on other animals. c. Third Period of Lnfancy. This requires no distinct consideration;—the growth of the child and activity of the functions going on as in the preceding period, but gradu- ally acquiring more and more energy. Within this period, a third molar tooth appears, which is not, however, temporary, but belongs to the permanent set. During the whole of infancy, the dermoid texture—skin and mucous membranes—is extremely liable to be morbidly affected; hence, the frequency of eruptive diseases, and of diarrhoea, aphthas, croup, bron- chitis, &c, many of which are of very fatal tendency. Owing, also, to the susceptibility of the nervous system, convulsions, hydrocephalus, and other head affections are by no means unfrequent. 2. CHILDHOOD. Childhood may be considered to extend from the seventh to the fif- teenth year, or to the period of puberty; and it is particularly marked by the shedding of the *first set of teeth, and the appearance of the second. It is manifest, that in the growth of the jaws with the rest of the body, the teeth, which, for a time, may have been sufficient in mag- nitude and number, must soon cease to be so; hence, the necessity of a fresh set, which may remain permanently. The process for the forma- tion of the permanent teeth is similar to that of the milk or temporary teeth ; yet it presents some remarkable points of difference and affords another surprising instance of the wonderful adaptation of means to definite objects, of which there are so many in the human body. It is well described by Mr. Thomas Bell,1 whose opportunities for observation have been unusually numerous, and whose zeal and ability in his profession, as well as in the prosecution of natural science, are well known. The rudiments of the permanent teeth according to him are not original, and independent, like those of the temporary. They are derived from the latter, and continue, for a consider- able time, attached to, and intimately connected with them. At an early period in the formation of the temporary teeth, the investing sac gives off a small pro- cess or bud, containing a portion of the a. Permanent Rudiment given off from essential rudiments, namely, the gulp the Temporary in an incisor. covered by its proper membrane. This 6. Permanent Rudiment given off from ... . ,-i -1 n- /i ,i the Temporary in a Molaris. constitutes the rudiment of the perma- nent tooth. It commences in a small thickening on one side of the parent sac, which gradually becomes more and more circumscribed, and at length assumes a distinct form, though 1 The Anatomy, Physiology, and Diseases of the Teeth, Lond., 1829; 2d Amer. edit., Philad., 1837. CHILDHOOD—SECOND DENTITION. 613 Fig. 517. still connected with it by a pedicle. For a time, the new rudiment is contained within the same alveolus as its generator, which is exca- vated by the absorbents for its reception. It is not, according to Mr. Bell, in consequence of the pressure of the new rudiment upon the bone, that this absorption is occasioned, but by a true process of anti- cipation ; for he states, that he has seen, in the human subject—and still more evidently in the foal—the commencement of the excavation before the new sac was formed, and, consequently, before any pressure could have taken place on the parietes of the socket. The absorption does not, indeed, begin in the smooth surface of the socket, but in the can- celli of bone immediately behind it. By degrees, a small recess is thus formed in the paries of the alveolus, in which the new rudiment is lodged, and this excavation continues to increase with the increasing size of the rudiment; whilst, at the same time, the maxillary bone be- comes enlarged, and the temporary tooth, advancing in its formation, rises in the socket. The new cell is thus gradually separated from the other, both by being itself more and more deeply excavated in the sub- stance of the bone, and also by the formation of a bony partition be- tween them, as seen in the marginal figure, 517, which exhibits the connection between the temporary tooth and the permanent rudiment, as it exists after the former has passed through the gum. As the temporary tooth grows and rises in the jaw, the connecting cord or pedicle elon- gates, and although the sac, from which it is derived, is gradually absorbed, it still remains attached to the neck of the temporary tooth. The situation of each permanent rudiment, when its corresponding temporary tooth has made its appearance through the gum, is deeper in the jaw and a little behind the latter, as represented in the mar- ginal illustrations, (Figs. 518 and 519,) of the upper and lower jaw after the whole of the temporaryteeth have passed through the gum. From these, it will be under- stood, how the upper part of the sac of the permanent rudiment, by means of the cord connected with the gum, gradually assumes the same relation to the gum as was originally sustained by the temporary rudiment. Such is the view adopted by most odontologists. It is generally believed, that the sacs of the per- manent teeth derive their origin from those of the milk teeth. Mr. Goodsir, however, maintains, and with much probability in favour of his view, that the two sets have an independent origin, and that each is developed in a distinct groove, (Fig. 510.) The cavity of reserve in which the permanent teeth are developed having been originally a process of the mucous membrane of the mouth; a rudi- ment of the Communication sub- Temporary Teeth and Permanent Rudiments. Temporary Tooth and Permanent Rudiment. Fig. 518. 614 AGES. Fig. 519. Temporary Teeth and Permanent Rudimenti. Fig. 520. Deciduous and Permanent Teeth, set. 7. Side View of Upper and Lower Jaw, showing the Teeth in their Sockets. The outer Plate of the Alveolar Processes has been taken off. 1. First incisors of upper jaw. jaw. 2. First incisors of lower sists even until the erup- tion of the permanent teeth, under the form of the fibrous cord referred to above, which becomes a gubernaculum or guide,—an iter deutis or path for the tooth. The ossification of the permanent teeth, for the in- cisors and first molaris, com- mences from the third to the sixth month afterbirth; about the ninth month, for the canine teeth; about three years, for the second mo- laris ; at three years and a half, for the fourth; and, at ten years, for the fifth; but all this is liable to much variation. The permanent teeth, during their formation, are crowded together in the jaw; but, as soon as they have advanced to a certain point, and can no longer be contained within their own alveoli, absorption of the anterior parietes of those cavities takes place, and the teeth are allowed to come in some measure forwards. In consequence of such ab- sorption, it frequently hap- pens, that not only the socket of the corresponding temporary tooth, but that of the tooth on each side is opened to the permanent one. Absorption of the root of the temporary tooth,— generally at the part nearest its successor,—now occurs, and this gradually proceeds as the latter advances, until the root is completely re- moved, when the crown falls off, leaving room for the permanent tooth to supply its place. It does not seem that this absorption of the CHILDHOOD—DENTITION. 615 root is produced by pressure on the part of the permanent tooth, as it often happens, according to Mr. Bell, that the root of the temporary tooth is wholly absorbed, and the crown falls out spontaneously, long before the succeeding tooth has approached the vacant space. As a general rule, however, the actions must be regarded consentaneous; and Mr. Bell thinks, that this absorption resembles that, already refer- red to, for the formation of a new cell to receive a permanent pulp, and that it may be termed, like it, a " a process of anticipation." In both instances, the existence, though not the pressure, or even the contact, of the new body is necessary to excite the action of the absorbent ves- sels ; and we, accordingly, find that in those cases, by no means unfre- quent, in which the temporary teeth retain their situation in the mouth with considerable firmness until adult age, the corresponding perma- nent teeth have not been formed. d e f g h Upper and Lower Teeth. a, a. Central incisors, b, b. Lateral incisors, c, c. Canine teeth, d, d. First bicuspidati. e, e. Second bicuspidati. /,/. First molares. g, g. Second molares. h, h. Third molares or denies sapientice. The following are the periods at which the permanent teeth gene- rally make their appearance. First molars...........7th year. Central incisors,.........8th Lateral incisors,.........9th First bicuspids,.........10th Second bicuspids,.........11th Canines,..........12th Second molars,........, 13th Third great molars, dentes sapientice,.....17th to 20th. When these have all appeared, the set is complete, consisting of thirty-two teeth, sixteen in each jaw,—the number of temporary teeth being only twenty. Fig. 521 represents the upper and lower perma- nent teeth in their alveoli or sockets, the external alveolar plate having been removed to show the mode in which they are articulated. Fig. 522 represents the same teeth when removed from the socket. While the jaws are becoming furnished with teeth and increasino- in 616 AGES. size, they undergo a change of form, and the branches become more vertical, so as to favour the exertion of force during mastication. When the teeth issue from the gums, they are most favourably situate for the act of mastication; the incisors are sharp, the canine pointed, and the molares studded with conical asperities; but, in the progress of age they become worn on the surfaces that come in constant contact. During the occurrence of these changes, which embrace the whole of the period we are considering, and extend, at times, into the next two, the animal functions, especially that of sensibility, become surprisingly developed, and the intellectual and moral results of a well adapted system of education strikingly apparent. The nutritive functions are, likewise, performed with energy, the body not yet having attained its full growth; and, towards the end of the period, the organs of repro- duction commence that developement, which has to be described pre- sently. The teeth appear with sufficient regularity to permit an inference to be drawn with regard to the age of the individual, and accordingly it has been proposed by Mr. Saunders1 to make them a test for age in reference to the children employed in the factories of Great Britain. According to him, the ages between seven and thirteen may be esti- mated in this manner; and Mr. Tomes2 remarks, that ajthough he is not aware, that the assertions of Mr. Saunders have be"en backed by extended statistical research, he is prepared to corroborate their gene- ral correctness. 3. ADOLESCENCE. The commencement of this age is marked by one of the most extra- ordinary developements, which the frame experiences; and its termi- nation by the attainment of full growth in the longitudinal direction. The period of the former of these changes is termed puberty; that of the latter the adult age. The age of adolescence has been considered to extend from fifteen years to twenty-five, in men; and from fifteen to twenty-one, in women; but this is only an approximation, like the other divisions of the ages, all of which are subject to great fluctuation in individual cases. M. Flourens makes it from ten to twenty3;—the latter being the period—he says—at which the epiphyses are united to the bones; and when this happens the body ceases to grow. During the periods we have considered, no striking difference exists in the appearance of male and female, except as regards the generative organs; but, about the age of puberty, essential changes occur, that modify the characteristics of the two sexes in a manner, which they maintain through the remainder of existence; and these changes affect the whole economy to a greater or less degree. In the male, the skin loses more or less of its delicacy and whiteness; the hair becomes darker; the areolar tissue condensed, and the muscles more bulky, so that they are strongly defined beneath the surface; the beard appears, 1 The Teeth, a Test for Age, considered with referenoe to the Factory Children, ad- dressed to the Members of both Houses of Parliament, Lond., 1837. See, also, Mr. A. Nasmyth, Researches on the Developement, &c, of the Teeth, p. 159, Lond.. 1849. 2 A Course of Lectures on Dental Physiology and Surgery, p. 118, London, 1848. 3 De la Longevite Humaine, &c, 2de edit., p. 46, Paris, 1855. ADOLESCENCE. 617 as well as hair upon the pubes, chest, and in the axillae. The different parts of the body become developed in such manner that the centre of the frame now falls about the pubes. The encephalon has increased in size, and has become firmer. The ossification of the bones, in the direction of their length, terminates towards the end of the period. The muscles become more red and fibrinous, losing the gelatinous character they previously possessed; and, in the animal, exhibiting those striking changes which we see—from veal to beef, from lamb to mutton, &c. The larynx undergoes great augmentation, and the glottis particularly is elongated and widened. The jaws complete their growth, and the dentes sapientiae appear so as to make up the full complement of six- teen teeth in each jaw. The changes in the nutritive organs are not great, consisting chiefly in their developement to correspond with the increased size of the frame. The greatest modification occurs in the organs of reproduction, which are now in a state to exercise their im- portant functions. The testicles, at puberty, suddenly enlarge so as to attain twice the diameter they previously possessed; and the secretion of sperm is accomplished. The penis is also greatly increased in size; and, according to M. Adelon,1 "becomes susceptible of erection." The susceptibility, however, exists long before this age. It may be noticed even in the first period of infancy. The scrotum assumes a deeper colour. Such are the chief changes that supervene in the male. In the female, they are not quite so striking;—the general habit remaining much the same as during childhood. The skin preserves its primitive whiteness; and, instead of the areolar tissue becoming more condensed, and the muscles more marked, as in the male, fat is deposited in greater quantity between the muscles, so that the form becomes more rotund. Hair appears on the organs of reproduction and in the axillae, whilst that of the head grows rarore rapidly. The developement of the genital organs is as marked as in the male. The ovaries attain double their previous dimensions; the uterus enlarges; and a secretion takes place from it which has been elsewhere described—the menstrual flux; the mons veneris and labia pudendi are covered with hair; the labia enlarge and the pelvis has its dimensions so modified as to render labour practicable. At an early age, the long diameter of the brim is from before to behind; but it is now in the opposite direction, or from side to side; and the bosom, which prior to this age, could scarcely be distinguished from that of the male, becomes greatly developed; fat is deposited so as to give the mammae their rotundity; the mammary gland is enlarged; and the nipple of greater size;—changes fitting the female for the new duties which she may be called on to exercise. The functions undergo equally remarkable modifications, under the new and instinctive impulse that animates every part of animal life. The external senses attain fresh, and peculiar activity; the intellectual faculties become greatly developed, and this is the period in which the mental character is more improved by education than any other. It embraces, indeed, the whole time of scholastic application to the higher studies. Prior to the end of the period, the male youth enters upon the avocation which is to be his future support, and both sexes may become established in life in the new relations of husband and wife 1 Physiologie de l'Homme, 2de edit., iv. 448, Paris, 1829, 618 AGES. and of parent and child. It is during this age, that an indescribable feeling of interest and affection is experienced between the sexes; and that the boldness of the male contrasts so strikingly with the captivat- ing modesty of the female,— " That chastity of look, which seems to hang A veil of purest light o'er all her beauties." The muscles having acquired their strength and spring, the severer exercises are now indulged, and mechanical pursuits of all kinds,— military and civil,—are undertaken with full effect. The expressions participate in the altered condition of the mental and moral manifes- tations, and indicate vivacity, energy, and enthusiasm. The voice of the male acquires a new character, and becomes graver, for reasons assigned elsewhere; whilst that of the female experiences but slight modification. The nutritive functions of digestion, absorption, and respiration experience little change; but nutrition, strictly so called, is evidently modified, from the manifest difference in the developement and structure of the various organs. The muscles contain more fibrin; the blood is thicker and richer in red corpuscles; and the excretions manifest a higher degree of animalization. Urea has taken the place of benzoic acid in the urine; and the cutaneous transpiration has lost its acidulous smell, and become rank and peculiar. Lastly, the sexual functions are now capable of full and active exercise, and appear to be intimately connected with the energy and developement of many parts of the economy. If the genital organs do not undergo the due change at puberty, or if the testes of the male or the ovaries of the female be removed prior to that age, considerable changes occur. These are more manifest in the male, inasmuch as the ordinary changes, that supervene at puberty, are in him more marked than in the female. The removal of the testicles, prior to puberty, arrests those changes. The beard does not appear, nor the hair in the axillae nor on the pubes, as in the entire male; and if those animals in which the males are distinguished by deciduous horns, as the stag,—or by crests and spurs, as the cock,— be castrated before their appearance, such appendages do not present themselves. If, however, they be castrated after puberty, they retain these evidences of masculine character. The eunuch, likewise, who becomes such after the appearance of the beard, preserves it, although to a less extent than usual. The developement of the larynx is arrested by castration, so that the voice retains, with more or less change, the treble of the period prior to puberty ; hence this revolting operation has been had recourse to for the sake of gratifying the lovers of music. In the course of age, we find that, during the progressive evolution of the organs, one set is liable to morbid affections at one period, aud a different set at another. In early age, the mucous membranes and the head are especially liable to disease; and, at the period we-are now considering, affections of the respiratory organs become more prevalent. It is indeed the great age for pulmonary consumption,—that fatal ma- lady, which, Sydenham supposed, destroys two-ninths of mankind. In the female, whose proper feminine functions do not appear at the due time, or are irregularly exercised, the commencement—indeed the whole of this period—is apt to be passed in more or less sickness and suffering. VIRILITY, OR MANHOOD. 619 4. VIRILITY, OB MANHOOD. M. Halle* has divided this age into three periods,—crescent, confirmed, and decrescent virility? The first of these extends from twenty-five to thirty-five in the male, and from twenty-one to thirty in the female; the second from thirty-five to forty-five in the male, and from thirty to forty in the female. Neither of these will require remark, the whole of the functions throughout this work,—when not otherwise specified, —being described as accomplished in manhood. Owing to the par- ticular evolution of organs, the tendency is not now so great to morbid affections of the respiratory function. It is more especially the age for cephalic and abdominal hemorrhages; accordingly, apoplexy and he- morrhoidal affections are more frequent than at any previous period. In decrescent virility,—in which M. Halle comprises the period of life between forty and fifty in the female, and between forty-five and sixty in the male,—signs of decline are often manifest. The skin may become shrivelled and wrinkled; the hair gray, or white and scanty; the teeth worn at the top, chipped, loose, and many perhaps lost. The external senses, especially the sight, are more obtuse, partly owing to a change in the physical portions of the organ, so that powerful spec- tacles become necessary, and partly owing to blunted nervous sensi- bility. Owing to the same cause, the intellectual faculties may be exerted with less energy and effect, and the moral manifestations be more feeble and less excitable. Locomotion is less active, owing to diminution in the nervous power, as well as probably to physical changes in the muscles, so that the individual may begin to stoop,— the tendency of the body to bear forwards being too great for the ex- tensor muscles of the back to counteract. The expressions participate in the condition of the intellectual and moral acts, and are, consequently, less exerted than in former periods. The nutritive functions do not exhibit any very remarkable change, and may even remain active to a good old age. The functions of reproduction show the greatest declen- sion, especially in the female. The male may preserve his procreative capabilities much longer than this period; but in the female the power is usually lost, the loss being indicated by the cessation of menstruation. After this, the ovaries shrivel, the uterus diminishes in size; the breasts wither; the skin becomes brown and thick; long hairs appear on the upper lip and chin, and all the feminine points are lost that were pre- viously so attractive. The period of the cessation of the menses is liable to many different disorders, which are the source of much annoy- ance, and are, at times, attended with fatal consequences. Prior to their total disappearance, they often become extremely irregular in their occurrence, sometimes returning every fortnight; debilitating by their frequency, and by the quantity of the fluid lost, and laying the foun- dation for uterine or other diseases of a serious character. Cancerous affections of the mammae or labia, which had been previously dormant or not in existence, now appear, become developed, and at times with extreme rapidity. In consequence of the great liability to such affec- tions, this has been called the critical age, critical period or critical 1 M. Flourens considers the first youth to extend from twenty to thirty; and the second from thirty to forty. 1!Yiq first virile age he makes from forty to forty-five ; and the second from fifty-five to seventy. De la Longevite Humaine, &c, 2de edit., p. 46, Paris, 1855. 620 AGES. time of life or turn of life. The danger to the female is not, however, so " critical" at this period as the epithet might suggest,—the statisti- cal researches of M. de Chateauneuf and of Lachaise, Finlaison,1 and others having shown, that between the ages of forty and fifty no more women die than men. M. Constant Saucerotte has, indeed, attempted to show by statistics on a great scale, that the mortality amongst women is greater between thirty and forty than between forty and sixty; and Muret, from his Statistics of the Pays du Vaud, did not find between forty afirl fifty a more critical period than between ten and twenty.2 5. OLD AGE. This is the age when every thing retrogrades. It is the prelude to the total cessation of the functions, where the individual expires— which is but rarely the case,—from pure old age. This period has been divided into three stages:—incipient or green old age, reaching to seventy years; confirmed old age or caducity, to eighty-five years; and decrepitude, from eighty-five years upwards. M. Flourens3 makes the first or green old age commence at seventy, and extend to eighty-five; and to this succeeds the second and last old age. In incipient or green old age, the declension that had occurred in the period of decrescent virility, is now more evident. The intellectual and moral manifestations may exhibit more marked signs of feebleness; and the muscular powers totter, and require the aid of a support—as well to convey a part of the weight of the body to the ground, as to enlarge the base of sustentation. The muscles of the larynx may participate in the general vacillation; the " Big manly voice, Turning again towards childish treble, pipes And whistles in the sound," and is broken and tremulous. The appetite is great, and the powers of digestion are considerable; but mastication is largely Fig- 523. deteriorated. In the first place, the teeth may fall out, in consequence of the constant deposition of fresh layers in the dental cavities, which ultimately close them, and obliterate the vessels that pass to the internal papillae for their nutrition. As soon as the teeth are lost, the alveolar processes, which supported them, waste away by absorption, and Skull of the Aged. the depth of the jaw is 1 Reports on the Evidence and Elementary Facts on which the Tables on Life Annui- ties are Founded, Lond., 1829. 2 Churchill, Outlines of the Principal Diseases of Females; American Medical Library edit., p. 82, Philad., 1839 ; or edit, by Dr. Condie, Philad. 8 Loc. cit. OLD AGE. 621 Physiognomy of the Aged. thus greatly lessened. On Fis- 524- these accounts, the jaws only approach each other at the forepart; the chin projects, and the angle of the jaw is thrown more forward. As the teeth and the sockets disappear, the alveolar margins be- come thin and sharp, and the gum hardens over them; the chin and nose necessarily approach (Figs. 523 and 524) ; the lips fall in, and the speech is inarticulate. We can thus understand the pe- culiarities of the mastica- tion of the aged. They are compelled to bite with the anterior portions of the jaws; for which rea- son as well as owing to the greater obliquity of the insertion of the levator muscles of the lower jaw, but little force can be exerted; and owing to the too great size of the lips, the saliva cannot be retained. Respiration is not as readily accomplished, partly owing to the com- plete ossification of the cartilages of the ribs, but chiefly to diminished muscular powers. The valves of the heart and many of the blood- vessels, especially of the extremities, become more or less ossified, and the pulse is somewhat slow and intermittent, but generally perhaps faster than in the adult. Of 255 women, between the ages of 60 and 96, examined by MM. Hourmann and Dechambre,1 the average num- ber of pulsations in the minute was 82*29; of respirations, 21*79. Nutrition is effected to such a degree only as to keep the machine in feeble action; and animal heat is formed to an inadequate extent, so that the aged require the aid of greater extraneous warmth : in many cases, the powers of reproduction in the male are completely lost. In confirmed old age, the debility of the various functions goes on augmenting. The mental and corporeal powers almost totter to their fall; and frequently a complete state of dementia or dotage exists. Often, however, we are gratified to find full intellectual and moral enjoyment prevailing even after this period, along with the possession of consider- able corporeal energy. The author had the honour to enjoy the friend- ship of three illustrious individuals of this country, two of whom had filled the highest office in the gift of a free people, all of whom are now no more; each of these gentlemen exhibited, after the lapse of eighty- two summers, the same commanding intellectual powers and the same benevolence that ever distinguished them. In this stage, locomotion becomes more difficult; the appetite is 1 Archiv. General, de Medec, 1825. 622 AGES. considerable, and the quantity eaten at times prodigious,—the digest- ive powers being incapable of separating the due amount of chyle from a quantity of aliment that was sufficient in the previous ages. Difficulty, however, sometimes arises in defecation, the muscular pow- ers being insufficient to expel the excrement. From this cause, accu- mulations occasionally take place in the rectum, which may require the use of mechanical means,—as injections, the introduction of an instrument to break them down, &c. Generation is, usually, entirely impracticable, erection being impossible; and during the whole of this and the next stage, the urinary organs are liable to disorder,—irritabi- lity about the neck of the bladder, and incontinence of urine, beincr frequent sources of annoyance. The density of the lungs, together with the quantity of blood they admit, diminishes with the progress of age; the thorax itself is gra- dually accommodated to the change; it becomes atrophied as the lungs are atrophied; it contracts as they contract, and the diminution in their vascularity, which is always in a ratio with the diminution of structure, shows the direct proportion between the lessened chemical and mechanical actions.1 Finally, to this stage succeeds that of decrepitude, so well described by Shakspeare:— " Last scene of all, That ends this strange, eventful history, Is second childishness, and mere oblivion; Sans teeth, sans eyes, sans taste, sans everything." As You Like It, ii. 7. The loss of power, mental and corporeal, becomes progressively greater; and, in addition to the abolition of most of the external senses—especially those of sight and audition—the intellectual facul- ties are, perhaps, entirely gone; all muscular motion is lost, and para- lysis requires constant confinement to the bed, or easy chair; the ex- cretions are passed involuntarily; sensibility becomes gradually ex- tinct, and life finally flits away as imperceptibly as the twilight merges in the shades of night; " nee subito frangitur; sed diuturnitate extin- guitur." M. Quetelet2 has deduced from extensive observations the relative heights and weights of both sexes at different periods of existence. The results are exhibited in the diagram. (Fig. 525). The increase in height is most rapid in the first year, and afterwards diminishes very gradually ; between the ages of 5 and 16, the annual increase is very regular. The difference between the height of the male and female at birth continues to augment during infancy and growth; but it is not very marked until about the 15th year, after which the female grows at a diminished rate; whilst the male goes on in nearly the same degree until about the age of 19. The female, consequently, arrives at her full height earlier than the male;—the full height of the latter not being generally attained until about the age of 25. At 1 Magendie, and MM. Hourmann and Dechambre. 2 Annales d'Hygiene Publique, vi. 89 ; and in his work, Sur l'Homme et le D^ve- loppement de ses Facultes, Bruxelles, 1835 ; or translation of the same, p. 63, Edinb., 1842. OLD AGE. 623 about 50, both sexes experience a diminution of stature, which con- tinues during the latter part of existence. The average height of the male and female who have attained their full developement is about 3^ times that of the new-born infant of the sexes respectively. The relative weight of the sexes corresponds pretty nearly with the height. Fig. 525. K I_____________!_______________I 1_____________________________________________.____________________I------------------L 0 5 70 15 20 25 30 /,0 50 60 10 Curves indicating the Developement of the Height and Weight of Male and Female at Differ- ent Ages. The preponderance exhibited by the male at birth increases gradually during the first few years; but towards the period of puberty the proportional weight of the female increases ; and about the age of 12 there is little difference between the sexes. After this, however, the weight of the male increases much more rapidly, especially between 15 and 20; subsequently, there is not much increase on the part of the male, although his maximum is not attained until the age of 40; whilst there is an absolute diminution on the part of the female, whose weight remains less during nearly the whole period of child-bearing. After this, however, her weight again experiences an increase, and its maximum is attained about 50. In old age, the weight of both sexes undergoes a diminution in nearly the same degree. The average weight of the male and female who have attained their full develope- ment is twenty times that of the new-born infant of the sexes respect- ively. Such is a brief description of the chief changes that befall the body in the different ages. To depict them more at length would be inconsistent with the object and limits of this work. It is clear, that, although the divisions, which we have adopted from Halle', are entirely arbitrary,—must run into each other, and be liable to nume- rous exceptions,—certain well-marked changes occur about the com- mencement or termination of many of them, and a singular diversity takes place in the successive evolution of organs; whilst some are predominant at one time, they fall behind others at a previous or 624 SLEEP. subsequent period; and such changes may lay the foundation for morbid affections in certain organs at one age, which do not prevail at another. The ancients, who believed that great mutations occur at particular intervals,—every three, seven or nine years, for example, aa the particular number might be at the moment in favour,—compared these periods to knots uniting the different stages of life, and giving the economy a new direction. These knots they called the climateric or climacteric years, and they conceived the body to be especially liable to disease at the periods of their occurrence. The majority assigned them to the number seven and its multiples ; and the fourteenth and twenty-first years especially were conceived to be replete with danger. Others applied the term climacteric to years resulting from the multi- plication of seven with an odd number, and especially with nine; the sixty-third year being regarded, by almost all, as the grand climacteric. The error with the ancients lay in considering that numbers exerted any agency. Every one admits the influence of particular evolutions on health; and, at the present day, the word climacteric is generally restricted to certain periods of life, at which great changes supervene, independently of any numerical estimate of years;—such as the period of puberty in both sexes;—that of the cessation of the menses or the critical time of life in the female, &c. It need hardly be remarked, that the different ages described, instead of extending through the protracted period of eighty-five years and upwards, may be varied by original constitution, climate, habits of life, &c, so that the stages may be shorter than usual, and all the signs of decrepitude occur many years earlier ; and, on the other hand, the period of decrepitude may, through strength of original conformation, and other causes, be largely postponed. CHAPTER II. SLEEP. The difference between the two classes of animal and nutritive functions is strikingly exhibited in the phenomena we have now to consider. Whilst the former are more or less suspended, the latter continue their action with but little modification. The functions of sensibility, voluntary motion, and expression cannot be indulged for any length of time, without fatigue being induced, and a necessity arising for the reparation of the nervous energy expended during their action. After a time,—the length of which is somewhat influended by habit,—the muscles have no longer power to contract, or the external senses to receive impressions ; the brain ceases to appreciate ; mental and moral manifestations are no longer elicited; the whole of the functions of relation become torpid, and remain in this state until the nervous system has been renovated, and adapted for the repetition of those functions, which, during the previous waking condition, had been exhausted. This state constitutes sleep; which, consequently, may be defined—the periodical and temporary suspension of all, or most, of those functions that connect us with the universe. The sus- SLEEP. 625 pension occurs in those functions and in those only; and hence the consideration of sleep, in many physiological treatises, has immediately followed that of the functions of relation. The nutritive functions continue regularly in action from the earliest period of fcetal formation; before mental manifestations exist in the embryo, and during sleep. For them there is no cessation, and scarcely any declension of ac- tivity, until the decadency of the frame affects them along with the whole of the machinery. Sleep, in the language of poetry, has been compared to death; and Dr. Good1 has stated, that the resemblance between them is not less correct upon the principles of physiology, than it is beautiful among the images of poetry. " Sleep is the death or torpitude of the voluntary organs, while the involuntary continue their accustomed actions. Death is the sleep or torpitude of the whole." Physiologically, the difference appears to us considerable. During the wbole of sleep a process of renovation is going on in the organs of animal life, which adapts them for subsequent activity, and contrasts signally with the state of annihilation that constitutes death; hence the important difference between healthy sleep, and the state of coma induced by any morbid cause, from which the patient is aroused languid and exhausted, instead of active and recruited. The foetus in utero is described by some as in a perpetual sleep, until aroused by the new actions established at birth; but even in this case there must be alternations of activity and suspension in the nervous functions. We have seen elsewhere, that they are manifestly more or less exerted during intra-uterine existence; nervous energy must therefore be expended; and renovation,—to a much less extent, it is true, than in the new-born child,—be necessary. Linnaeus,2 under the term somnus plantarum, comprehends a peculiar state in the constitution of many plants during the night, as evinced by a change of position, generally a drooping or folding together of their leaves or leaflets; such a change being occasioned by the withdrawal of the stimulus of light, and, probably, it has been conceived, constituting a state of rest to their vital functions; but it is obvious, that there can be no similitude between this condition and that of the sleep of animals, which is con- fined to the functions of relation,—functions that do not even exist in the vegetable. The approach of sleep is indicated by signs, that are unequivocal, and referable to the encephalon. The great nervous centre of animal life feeling the necessity for rest and renovation, an internal sensation arises in it, as well as in the whole of the nervous system over which it presides, termed sleepiness or the sensation or want or desire of sleep, which, provided the waking state has been protracted, ultimately be- comes irresistible, and often draws on sleep in spite of every effort to the contrary. It is affirmed, that boys, exhausted by exertion/dropped asleep amid the tumultuous noise of the battle of the Nile; and the fatigued soldier has often gone to sleep amid discharges of artillery. An engineer has been known to fall asleep within a boiler whilst his fellows were beating it on the outside with their heavy hammers. ' Book of Nature, 3d edit., ii. 203, Lond., 1834. 2 Amoenitat. Academ., torn. iv. VOL. II.—40 626 SLEEP. Noises will at first prevent sleep, but the desire is ultimately so invin- cible, that they cease to produce any effect. In the noisy inns of larux,p. 241,Paris, 1824; and De la Longevite Humaine, &c, edit, cit.,p. 195. D Medical Examiner, Sept., 1852, p. 5ti5. 698 LIFE. nating mammalia by minutes. Death in such cases he refers to insuffi- ciency of respiration.1 Prior to the time of Haller, the nervous system was looked to as the great source of power in the animal body; and the contractile action of the muscles,—described at length under the head of Muscular Mo- tion,—was considered to be wholly derived from the nerves, which were supposed to transmit the power to the muscular fibre as it was called for,—accurately regulating the quantity supplied. Haller con- tended for a vis insita, a power of irritability or contractility, essentially residing in the muscles themselves, independently of any condition of the nervous system, and called into action by stimuli, of which the nervous influence is one,—contributing, however, like other stimuli, to exhaust it, instead of furnishing any fresh supply. We have elsewhere shown, that a muscle is capable of being thrown into contraction after a limb has been removed from the body, and for a considerable period after the cessation of respiration, circulation, and consequently of in- nervation, provided the appropriate stimuli be applied, so as to excite the vis insita, which remains in the muscle for some time after dissolu- tion ; and if all the nerves, supplying the limbs of a frog, be divided and cut out close to the place where they enter the muscles, the muscles will still retain their contractility in as great a degree as when the nerves were entire. It has been affirmed by an excellent observer,*1 that after tying the femoral artery or vein, or dividing the sciatic nerve in frogs, the full strength of the muscles remained unaltered for several days,—in one case as many as twelve. They, who believe that the con- tractility of muscles is wholly derived from the nervous system, main- tain, however, that in such case the stimulus may still act through the medium of portions of nerves always remaining attached to the muscle, however carefully attempts may have been made to remove them; and some have supposed, that these nervous fibres may even constitute an essential part of the muscular fibre. The most satisfactory reply, that has been made to this argument, is the following experiment of Dr. Wilson Philip.3 All the nerves supplying one of the hind legs of a frog were divided, so that it became completely paralytic. The skin was removed from the muscles of the leg, and salt sprinkled upon them, which, being renewed from time to time, excited contraction in them for twelve minutes: at the end of this time they were found no longer capable of being excited. The corresponding muscles of the other limb, in which the nerves were entire, and of which, consequently, the animal had a perfect command, were then laid bare, and the salt ap- plied to them in the same way. In ten minutes, they ceased to con- tract ; and the animal had lost command of them. The nerves of this limb were now divided, as those of the other had been, but the excita- bility of the muscles to which the salt had been applied was gone. It caused no contraction in them. After the experiment, the muscles of the thighs in both limbs were found to contract forcibly on the appli- 1 Medical Examiner, Sept., 1852, p. 569. 2 Valentin, Lehrbuch der Physiologie des Menschen, ii. 176-192. 3 An Experimental Inquiry into the Laws of the Vital Functions, &c, p. 100, Lond., 1817. LIFE POWER AND NERVE POWER. 699 cation of salt. It excited equally strong contraction on both sides. In this experiment, the excitability of the muscles, whose nerves were entire, was soonest exhausted; and hence Dr. Philip1 properly con- cluded, that the nervous influence, far from bestowing excitability on the muscles, exhausts it like other stimuli; and that excitability or irritability is a property of the muscle itself. This is confirmed by the fact, that, when the vital properties of nerves are destroyed by the application of narcotic substances, the irritability of the muscle to which they are distributed may remain for some time longer; so that they must be independent of each other. Experiments have been per- formed by Harless,2 on animals rendered completely insensible by in- halation of ether, which confirm this view. He found, that even when the nervous system had been rendered by the action of ether utterly incapable of conveying a galvanic stimulus applied either to the nerv- ous centres or to the nervous trunks; the same stimulus, applied directly to the muscles, would immediately throw them into powerful con- traction. Dr. Madden, too, communicated some years ago, to the British Association at its meeting in Edinburgh, the results of the agency of narcotics in destroying the power of nervous conduction, without diminishing muscular contractility in an equal degree.3 The opinion of Professor Miiller is, that if muscular irritability be not dependent upon the brain and spinal cord, they supply some in- fluence essential to its exercise; and in confirmation of this he lays much stress on the loss of irritability by muscles within a few weeks after the section of their nerves. This, however, has been shown by Dr. J. Eeid4 to be owing to the altered nutrition consequent on their disuse. He divided the spinal nerves as they lie in the lower part of the spinal canal in four frogs, and both posterior extremities were thus insulated from their nervous connexions with the cord. The muscles of the paralysed limb were daily exercised by a weak gal- vanic battery; whilst those of the other limb were permitted to re- main quiescent. This was continued for two months; at the end of which time the muscles of the exercised limb retained their original size and firmness, and contracted vigorously, whilst those of the qui- escent limb had shrunk to at least one-half of their former bulk, and presented a marked contrast with those of the exercised limb. The muscles of the quiescent limb still retained their contractility, even at the end of two months; but Dr. Eeid thought there could be little doubt, that, from their imperfect nutrition, and the progressing changes in their physical structure, this would in no long time have disap- peared, had circumstances permitted the prolongation of the experi- ment. The experiments of Dr. Brown-Sequard5 are highly confirmatory of Haller's doctrine. He found, that muscles and nerves which had lost their excitability, could have it restored by arterial blood sent into their vessels. He frequently observed, also, that muscles, 1 Lond. Med. Gazette, March 18 and 25, 1837. 2 Muller's Archiv., H. ii. S. 228, Jahrgang, 1S47. 3 Brit, and For. Medico-Chirurg. Review, July, 1848, p. 245, 4 Edinburgh Monthly Journal of Med. Science, May, 1841. 6 Med. Examiner, August, 1852, p. 485, and May, 1853, p. 280. 700 LIFE. paralysed for five days or a little more, in consequence of the division of their nerves, remained much longer contractile after the death of the animal than the sound muscles; which—as he well remarks— would scarcely be the case if the excitability were communicated to muscles by the nervous system. This essential characteristic of living bodies—manifested in their moving responsive to some stimulus—is a distinct vital property, to be noticed presently, which is not confined, as Haller supposed, to the muscular structure, but exists over the whole body; and in con- firmation of its not being dependent upon the nerves, is the fact of its presence in the vegetable as well as in the animal. Many plants ex- hibit the property in a remarkable manner. The barberry bush is one of these. In this flower, the six stamens, spreading moderately, are sheltered under the concave tips of the petals, till some extraneous body, as the feet or trunk of an insect in search of honey, touches the inner part of each filament near the bottom. The irritability of that part is such, that the filament immediately contracts there, and conse- quently strikes its anther, full of pollen, against the stigma. Any other part of the filament may be touched without this effect, provided no concussion be given to the whole. After a while, the filament re- tires gradually, and may be again stimulated; and when each petal, with its annexed filament, has fallen to the ground, the latter, on being touched, shows as much irritability as ever. In another plant,— Cis- tus helianthemum, dwarf cistus or lesser sunflower,—the filaments, when touched, execute a motion, the reverse of that of the barberry. They retire from the style and lie down, in a spreading form, upon the petals. Owing to the possession of this property, Apocynum androsozmifolium or dogsbane is extremely destructive to insect life. Attracted by the honey on the nectary of the expanded blossom, the instant the trunk of the fly is protruded to feed on it, the filaments close, and, catching the fly by the extremity of its proboscis, they detain the insect until its struggles end in death occasioned apparently by exhaustion alone. The filaments then relax, and the body falls to the ground.1 These are only evidences, however, of particular parts possessing an unusual degree of irritability. The property exists in every part of the plant, and, as in the animal, is the essential characteristic of life. It forms a medium of communication between the various parts of the living machine, and is excited to action by extraneous influences. All its movements, however, appear to be dependent upon appropriate sti- muli, and are, consequently, passively exercised. In all organized bodies a force or impulse exists, which gives occa- sion to the formation of its constituent tissues and organs according to a definite plan; gradually developing the plant from the seed, as it does the animal from the ovum or egg, so unerringly, that no confu- sion results; and enabling the shape, size, and duration of the oak to be as assuredly pronounced from the inspection of the seed, as those of the bird can be from its ovum or egg:—a vital force, in other words, is present, which presides over, as it were, and directs the movements of living bodies in their structural developement, and 1 Sir J. E. Smith, Introduction to Botany, p. 211. LIFE POWER AND NERVE POWER. 701 whose agency does not cease until every trace of movement is imprac- ticable; and the being—animal or vegetable—ceases to live. The germ of the chick is surrounded in the egg by the nourishment needed for its developement; but, so far as the eye can see, when aided by the ' most powerful microscope, that germ possesses no nerves; no blood; both of which have been regarded by many as indispensable to the growth of parts in the fully developed animal. Yet gradually, under special arrangements of cells, tissue after tissue becomes formed; organ after organ is evolved in succession, until the full period of incubation is attained, when the young animal breaks the shell to assume an in- dependent existence, perfect in an organization moulded and fash- ioned under its own life power. Cells exist at first without the slightest appearance of bloodvessels; gradually, however, minute dots become perceptible, which coalesce; and blood is seen before continuous ves- sels are prepared to receive it. Yessels exist before the heart. Vas- cular tubes are formed and become filled with blood. At first, these tubal fragments are seen to be distinctly separated from each other; but, subsequently, they become united; and when a powerful central and muscular organ—the heart—is superadded, the apparatus of the circulation is complete, and fitted for its great objects. So is it in re- gard to the neurine or nervous matter, which, in the aggregate, forms the nervous system. Evolved in distinct portions—nerve points—in detail as it were, it is not adapted for that wonderfully perfect inter - nuncial system of association, which unites the various parts of a com- plicated and dependent machine, until the separate portions have united, and the various ramifications have become connected with cen- tral ganglions, to which, in the higher organisms, impressions, received by the sentient extremities of the nerves, have to be conveyed. We thus comprehend, that life power and nerve power are by no means identical;—that the former exists before nerves or vessels are developed; and in the vegetable kingdom throughout, not in the humblest moss only, but in the fairest flower of the parterre, and in the gigantic occupant of the forest, we may in vain look for aught resembling the nervous system of man and the higher animals. It is true—as before remarked—that the pith of the vegetable has been likened by Brachet and some others to the neurine of the animal, and a ganglionic nervous system has been ascribed to the former; but how forced must be the analogy between the morphology of vegetable pith and that of animal neurine, and how defective the evidence in favour of their functional identity or even resemblance! If this, then, be conceded, we must equally admit, that all the func- tions, which are exercised by vegetable bodies, are carried on without nervous agency. Nutriment must be received from without; the fluid which passes from cell to cell, or in vessels formed by the aggregation of such cells, and which is the pabulum for all nutritive action, must be in constant progression, and be conveyed to the surface of the • leaves, in order that it may receive from the air the same kind of in- dispensable influence, which is impressed upon the blood in the lungs: from this fluid must be formed every secretion—bland or acrid, fra- grant or repulsive, of which the vegetable kingdom presents so vast a variety. Every product of nutrition, from the coarsest vegetable fibre 702 LIFE. to the most delicate and exquisitely formed petal;—all can be, and are, evolved, under the influence of that pervading life power, as perfect in its kind as in the most perfect animal. In the lowest confines of the animal creation, where—as in the monad or in the simple primordial cell—we may in vain look, with the aid of the most powerful micro- scope fabricated by the most skilful of modern mechanicians, for the presence of nervous centres or even of rudimental nerves—nerve points—all the organic functions are accomplished much in the same manner as in the vegetable ; and it is only as we ascend the scale, and discover in the series a more and more complicated nervous apparatus, that the problem becomes more complicated. The nervous system is destined for the most elevated role; and whilst its functions are most mysterious and pervading, so as to modify materially the degree of the nutritive actions, the conclusion is irresistible, that they are not car- ried on by it; but are the result of the life or instinctive force which is seated in every living tissue. To this life force whose movements or impulsions are active and varied, the term instinct has been appropriated by Virey,1 Fleming,2 Good,3 and -others. It is an extension of the ordinary acceptation of the term; but enables us to understand the phenomena better than when we restrict it to those manifestations of man, or animals, that bear the semblance of reason. It is this power, which, according to those gentlemen, regulates the movements, that are requisite to obtain a sup- ply of food, to remove or counteract opposing obstacles, and to fly from impending danger, or repair injuries. " In every organized sys- tem," says Dr. Good,4 " whether animal or vegetable, and in every part of such system, whether solid or fluid, we trace an evident proof of that controlling, and identifying power, which physiologists have de- nominated, and with much propriety, the principle of life. Of its cause and nature we know no more than we do of the cause and nature of gra- vitation, or magnetism. It is neither essential mind nor essential matter; it is neither passion nor sensation ; but, though unquestionably distinct from all these, is capable of combining with any of them ; it is pos- sessed of its own book of laws, to which, under the same circumstan- ces, it adheres without the smallest deviation; and its sole and uniform aim, whether acting generally or locally, is that of health, preserva- tion, or reproduction. The agency by which it operates is that which we denominate or should denominate instinct, and the actions by which its sole and uniform aim is accomplished are what we mean, or should mean, by instinctive actions; or to speak somewhat more precisely, instinct is the operation of the livng principle, whenever manifestly directing its operations to the health, preservation or reproduction of a living frame, or any part of such frame. The law of instinct, then, is the law of the living principle; instinctive actions are the actions of the living principle; and either is that power, which characteristically distinguishes organized from unorganized matter, and pervades and regulates the former, uniformly operating by definite means in definite 1 Art. Instinct, in Diet, des Sciences M'dicales, xxv. 367. 2 Philosophy of Zoology, i. 14, Edinb., 1822. 3 Book of Nature, ii. 114, London, 1826. 4 Ibid., ii. 132. INSTINCT IN THE ANIMAL AND VEGETABLE. 703 circumstances, to the general welfare of the individual system or of its separate organs, advancing them to perfection, preserving them in it, or laving a foundation for their reproduction, as the nature of the case may require. It applies equally to plants and to animals, and to every part of the plant, as well as to every part of the animal, so long as such part continues alive. It is this, which maintains from age to age, with so much nicety and precision, the distinctive characters of differ- ent kinds and species; which carries off the waste or worn out mat- ter supplies it with new, and in a thousand instances, suggests the mode of cure, or even effects the cure itself, in cases of injury or dis- ease. It is 'the divinity that stirs within us' of Stahl, the vis medica- trix'naturoz of Hoffmann and Cullen and the physicians of our day, &c.&c." . „ n Of the existence of this instinctive force we may adduce a few more ex- amples from both the vegetable and the animal kingdom. When the seed of a plant is deposited in the ground, under circumstances favourable for its developement, it expands, and the root and stem are evolved. The root descends into the ground, manifestly not from the laws of gravita- tion, but owing to some inherent force, inasmuch as it penetrates the earth, which is of much greater specific gravity than itself. The stem, too, bursts through the earth, and rises into the air, notwithstanding the air'is of much less specific gravity; until having attained the height to which the action of the vital force limits it, its upward developement ceases. It rarely happens, however, that the root is capable of procuring nourishment sufficient for its future developement in immediate contact with it. It, therefore, sends out numerous filamentous radicles in all directions to search after food, and convey it to the proper organs. The number and direction of these filaments, and the distance to which they extend, are regulated by the necessities of the plant, and the sup- ply of the soil. A strawberry offset, planted in sand, will send out' almost all its runners in the direction in which the proper soil lies nearest; and few, and sometimes none, in the direction in which it lies most remote.1 When a tree, which requires much moisture, has sprung up, or been planted in a dry soil, in the vicinity of water, it has been observed, that a much larger portion of its roots has been directed to- wards the water, and that when a tree of a different species, and which requires a dry soil, has been placed in a similar situation, it has appeared, in the direction given to its roots, to have avoided the water and moist soil. When a tree, too, happens to grow from seed on a wall, it has been seen, on arriving at a certain size, to stop for a while, and send down a root to the ground. As soon as this root has been established in the soil, the tree has continued increasing to a large magnitude^ The fact has been often noticed with respect to the ash,—a tree, which in consequence of the profusion of its seed, is found more often scattered in wild and singular places, than in any other not propagated by the agency of birds, or conveyed by the winds. We find, in all cases, that if the roots of a plant, spreading in search of nourishment, meet with interruption in their course, they do not arrest their progress, but either attempt to penetrate the opposing body, 1 Fleming, op. citat., p. 16. 704 LIFE. or avoid it by altering their direction. Dr. Fleming1 states that he has repeatedly seen the creeping root of Triticum repens or couch grass piercing a potato, that had obstructed its course. It is well known, too, that roots will pass under a stone wall or a ditch, and rise up on the opposite side. A striking case of this nature was communicated to the author, by his venerable friend, the late Ex-President Madison. The wooden pipes, for the conveyance of Water to Mr. Madison's esta- blishment, having become obstructed, they were carefully examined; when it was found, that the roots of a honeysuckle, growing imme- diately above a plug, made of the wood of Liriodendron tulipifera or American poplar, which is of soft consistence, had penetrated the plug in various places to reach the water, and formed an agglomerated mass in the pipe which completely precluded the passage of water along it. The nearest approximation to these manifestations of instinct in the animal, occurs in the formation of the new being, and in the first actions that take place after birth. From the moment of the admix- ture of substances furnished by the parents at a fecundating copulation, there must be a force existing in the embryo, which directs the construc- tion and arrangement of its organs after a definite manner ; and always according to that peculiar to the species. In the egg, this is seen most distinctly. The germ of the chick is surrounded by the nourishment requisite for its formation, until the young animal breaks the shell. At this time, it has within it a portion of nutriment derived from the yolk drawn into its body. This supplies its wants for a short period; but it soon becomes necessary, that it should select and collect food for itself, and we observe it throwing its various organs into action for prehension, mastication, deglutition, &c, as if it had been long accus- tomed to the execution of these functions. In the formation of the human foetus in utero the same instinctive action is observable in the successive evolution of organs, and in the limitation of the body to a determinate shape, size, structure, &c.; and when these requisites have been attained, the child bursts the membranous envelope, and is extruded, to maintain thenceforth an existence independent of the mother. More helpless, however, than the young of the animal king- dom in general, the infant requires the fostering care of the parent for the purpose of supplying it with the necessary nutriment; but as soon as food is conveyed to the lips, the whole of the complicated process of deglutition is effected for the first time, with the same facility as after long practice. As we descend in the animal kingdom, we find these inward actions that constitute instinct more and more largely exhibited. In the quadruped, it is not necessary, that the nipple should be applied by the mother to the mouth of the new-born animal. It is sought for by the latter ; discovered, and seized hold of, by the appropriate organ of prehension, the mouth. The lips are applied; the air is exhausted; and the milk flows according to exact principles of hydrostatics, but without the animal having the least knowledge of the physical process it accomplishes. Naturalists, indeed, assert, that before the calf has been more than half extruded from the mother, it has been seen to 1 Op. citat., p. 18. INSTINCT IN THE ANIMAL AND VEGETABLE. 705 turn around, embrace and suck the maternal teat. As we descend still farther in the scale of creation, we discover the manifestations of in- stinct yet more signally developed ; until, ultimately, in the very low- est classes of animals, the functions are exercised much in the same manner as in the vegetable; and appear to be wholly instinctive, with- out the slightest evidence of that intelligence, which we observe in the upper classes of the animal kingdom, and pre-eminently in man. This, however, applies only to the very lowest classes; for, a short way higher up the scale, we meet with apparent intelligence, united with instinct, in a manner that is truly surprising and mysterious. Again, the similarity of the actions of the instinctive principle in the animal and the vegetable is exhibited by the reparatory power which both possess when injuries are inflicted on them. If a branch be for- cibly torn from a tree, the bark gradually accumulates around the wound, and cicatrization is at length accomplished. The great utility of many of our garden vegetables,—as spinach, parsley, cress, &c.—de- pends upon the possession of a power to repair injuries, so that new shoots speedily take the place of the leaves that have been removed. Similar to this is the reparatory process, instituted in the lobster that has lost its claw, the water-newt that has lost an extremity, or an eye ; in the serpent deprived of its tail, and the snail that has lost its head. These parts are reproduced as the leaves are in the spinach or parsley. Few animals, however, possess the power of restoring lost parts; whilst all are capable of repairing their wounds when not excessive, and of ev- erting a sanative power, when labouring under disease. If a limb be torn from the body, provided the animal should not die from hemor- rhage, a reparatory effort is established, and if the severity of the injury should not induce too much irritation in the system, the wound gradually fills up, and the skin forms over it. To a lesser extent we see this power exerted in the healing of ordinary wounds, and in the cementing of broken bones ; and although it may answer the purpose of the surgeon to have it supposed, that he is possessed of healing salves, &c, he is well aware, that the great art in these cases is to keep the part entirely at rest, whilst his salves are applied simply for the purpose of keeping the wound moist; the edges in due apposition, where such is necessary; and preventing extraneous bodies from having access to it;— his trust being altogether placed in the sanative influence of the instinct- ive power situate in the injured part, and in every part of the frame. It is to this.power, that we must ascribe all the properties, assigned to the famous sympathetic powder of Sir Kenelme Digby,—which was supposed to have the wonderful property of healing wounds, when merely applied to the bloody clothes of the wounded person, or to the weapon that had inflicted the mischief;—a powder, which, at one time, enjoyed the most astonishing reputation.1 The wound was, however, always carefully defended from irritation by extraneous substances; and it has been suggested, that the result furnished the first hint, that led surgeons to the improved practice of healing wounds by what is technically called the first intention. It is to this instinctive principle, 1 A Late Discourse made in a Solemn Assembly of Nobles and Learned Men at Mont- pellier in France ; by Sir Kenelme Digby, Knight, &c, London, 1658. VOL. II.—lb 706 LIFE. so clearly evinced in surgical or external affections, but at times, not less actively exerted in cases of internal mischief, that the term vis medicatrix naturae has been assigned; and, whatever may be the ob- jections to the views entertained regarding its manifestations in disease, that such a power exists can no more be denied than that organized bodies are possessed of the vital force. We have too many in- stances of recovery from injuries, not only without the aid of the practitioner, but even in spite of it, to doubt for a moment, that there is, within every living body, a force or impulse manifestly directed to the health and preservation of the frame, and of every part of it. So far, then, it is manifest, the instinctive actions of the animal and vegetable are exerted according to the same laws, and probably through similar organs. This, at least, applies to the lowest of all animated beings, where the difference between them and the vegetable is small indeed. It applies equally to the human foetus, which can be con- sidered but to vegetate during the greater part of utero-gestation; and even for some time after birth its actions are purely instinctive, and differ but little from those of the vegetable, except that, owing to the morphology of its nervous system, the acts are of a more compli- cated character. It is only when the brain has become duly developed, and the external senses fully so, that it exhibits so decidedly the difference between those acts, which it had previously accomplished instinctively, and the elevated phenomena of sensibility, which man enjoys so pre-eminently, but are likewise possessed, to a greater or less extent, by the whole animal creation. The cells of the ordinary honeycomb are intended for the larvae of the different varieties of the occupants of the hive. These cells are usually placed horizontally, with their mouths opening towards the sides of the hive. The bottom of the cells, instead of forming one flat square, is composed of three lozenge-shaped pieces, so united as to make the cell end in a point; consequently, the whole forms an hexa- gonal tube, terminating in a pyramidal cavity. If the two cells had been a single hexagonal tube, intersected in the middle by a flat, instead of a pyramidal, division, not only would the shape have failed to answer the purpose of the bees, but more wax would have been expended in its construction. Hence, it would seem, that both the body and base of the tube are adapted for their object; the greatest strength and the greatest capacity being obtained with the least expenditure of wax in an hexagonal tube with a pyramidal base. Be'aumur, when inquiring into the habitudes of these industrious animals, requested Konig, an able mathematician, to solve the following question:—Among all hexa- gonal tubes with pyramidal bases, composed of three similar and equal rhombs, to determine that which, having the same capacity, can be constructed with the least possible quantity of matter? Konig, not aware of the precise object of Eeaumur's inquiry, solved the problem, and found,—that if three rhombs or lozenges are so inclined to each other that the great angles measure 109° 26', and the little angles 70° 34', the smallest possible quantity of matter will be needed. Maraldi measured the angles actually formed at the bottom of a cell, and found that the great angles gave 109° 28' and the little 70° 327 All this, 1 See, also, Mr. Maclaurin, Philosophical Transactions, vol. ix. INSTINCT IN THE ANIMAL AND VEGETABLE. 707 however, may be ascribed to blind instinct, proceeding uniformly in the same track, without any evidence of the admixture of reason; but we have innumerable instances, in the same insects, to show, that their operations are varied according to circumstances, and that intelligence is manifestly expended in the adaptation of means to definite purposes. Of this we shall give but one example. Huber, whose inquiries into this part of entomology have been singularly minute and accurate, having had great ravages committed on his hives by the sphinx atro- pos or death's head moth, determined to construct a grating, which should admit the bee but not the moth. He did so, and the devasta- tion ceased. He found, however, that in hives, not protected by his agency, the bees had adopted a similar expedient for their defence; and these defences were variously constructed in different hives. "Here, was a single wall whose opening arcades were disposed at its higher part; there, were several bulwarks behind each other, like the bastions of our citadels: gateways, masked by walls in front, opened on the face of the second rows, while they did not correspond with the apertures of the first. Sometimes, a series of intersecting arcades per- mitted free egress to the bees, but refused admittance to their enemies. These fortifications were massy, and their substance firm and compact, being composed of propolis and wax." Take, again, the case of the solitary wasp, so graphically given by the Rev. Sydney Smith.1 "She digs several holes in the sand, in each of which she deposits an egg, though she certainly knows not that an animal is deposited in that egg,—and still less that this animal must be nourished with other animals. She collects a few green flies, rolls them up neatly in separate parcels (like Bologna sausages), and stuffs one parcel into each hole where an egg is deposited. When the wasp- worm is hatched, it finds a store of provisions ready made; and what is most curious, the quantity allotted to each is exactly sufficient to support it, till it attains the period of wasphood, and can provide for itself. This instinct of the parent wasp is the more remarkable as it does not feed upon flesh itself. Here the little creature has never seen its parent; for, by the time it is born, the parent is always eaten by spar- rows; and yet, without the slightest education, or previous experience, it does everything that the parent did before it. Now the objectors to the doctrine of instinct may say what they please; but young tailors have no intuitive mode of making pantaloons;—a new-born mercer cannot measure diaper;—nature teaches a cook's daughter nothing about sippets. All these things require with us seven years' appren- ticeship; but insects are like Moliere's persons of quality:—they know everything (as Moliere says), without having learnt anything;—' Les gens de qualite savent tout, sans avoir rien appris.' " It would be endless, and beyond the design of this work, to enume- rate the various evidences of intelligence exhibited by the insect tribe, in fulfilling the ends for which they have been destined by the Great Author of nature. In all our reasonings on the subject of instinct, we must be com- 1 Elementary Sketches of Moral Philosophy, p. 244, London, 1850; see, also, Lay- cock, in Brit, and For. Med.-Chir. Rev., July, 1855, p. 166. 708 LIFE. pelled to admit, in the case of most animals at least, a degree of intel- ligence that strikingly modifies those actions, the impulse to which is doubtless laid in organization. The precise line of demarcation between instinctive acts and reason cannot, however, be established; and this has led some philosophers to call in question the existence of the former. It is owing to the union of intelligence with instinct, that we find ani- mals accommodating themselves to circumstances, so that if prevented from adopting the habits that belong to the species, they have recourse to others as similar as possible. Thus, if a bird be prevented from building its nest in a particular situation, or from obtaining the mate- rial, which birds of its own species employ, it has recourse to other materials and to another situation, as like those that are appropriate to it as is practicable. The rook usually and instinctively builds its nest on the summit of the tallest trees; but Dr. Darwin,—who is one of those that call in question the influence of instinct,— asserts, that in Welbourn churchyard, a rookery was formed on the outside of the spire, and on the tops of the loftiest windows. There had formerly been a row or grove of high trees in the neighborhood, which had been cut down; and, in consequence, the birds exhibited the union of intel- ligence with instinct, by building on the lofty spire and windows. In like manner, the jackdaws of Selbourne, according to Mr. White, not finding a sufficiency of steeples and lofty houses on which to hang their nests in that village, accommodated themselves to circumstances, and built them in forsaken rabbit burrows.1 In Africa, which abounds in numerous beasts and birds of prey, all the feebler species of the feathered tribe would seem to have contrived some means of protection and security for their reproduction. Some so construct their nests, that they can only be entered by one small aperture; others suspend them from the extremities of small branches of trees. A species of loxia always hangs its nest from a branch extending over a river or pool, the opening into its long neck almost touching the water. "A note in my Journal,"—says Sir John Barrow,2—" observes, that the sparrow, in Africa, hedges round its nest with thorns; and even the swallow, under the eaves of houses, or in the rifts of rocks, makes a tube to its nest of six or seven inches. The same kinds of birds in Northern Europe, having nothing to fear from monkeys, snakes, or other noxious animals, construct open nests; and I ask is this difference the effect of mere accident or of design ? Is it, I might have added, the effect of imitation or observation?" By Stahl,3 and the animists in general, as well as by more recent philosophers, all the phenomena of instinct have been referred to ex- perience, so obscure as not to be easily traceable, but not the less certainly existent. The insect tribes, however, furnish us with many cases where the young beings can never see their parents, and can, of course, derive no benefit from the experience of progenitors; yet their habits are precisely what they have probably ever been ; so uniform, indeed, as to compel us to refer them to some constant impulse con- 1 Natural History of Selbourne, with additions, by Sir W. Jardine, Amer. edit., p. 82, Philada., 1832. 2 An Autobiographical Memoir of Sir John Barrow, Bart., p. 193, Lond., 1847. 3 Theoria Vera Medica, Hal.. 1737. SEAT OF INSTINCT. 709 nected with their special organization, and, consequently, instinctive. In support of the existence of these natural impulsions, the common occurrence of a brood of young ducks, brought up under a hen, may be mentioned.1 These little beings, soon after they have broken the shell, and contrary to all the feelings and instincts of the foster-mother, seek the water, and suddenly plunge into it, whilst the hen herself does not dare to follow them. By what kind of experience or observ- ation,—it has been asked,—by what train of thought or reasoning has the scarcely fledged brood been able to discern that a web-foot adapts them for swimming ? Any experience they can have derived must have taught them to shun the'water; yet, notwithstanding this, instinct points out to them habitudes for which they are adapted, and its indi- cations are obeyed in spite of every kind of counter-experience. It is impossible to refer these acts to imitation, for there is no opportunity afforded for it. Sir James Hall, cited by Mr. Dugald Stewart in his " Lectures," hatched some chickens in an oven; and within a few hours after the shells were broken, a spider was turned loose before the newly- hatched brood, which had not proceeded many inches, before it was descried by one of them, and devoured.2 Attempts have occasionally been made to domesticate the wild turkey of this continent, by bringing the young up under the common turkey, but they have always resumed the -way of life to which instinct directed them, when opportunity offered; in accordance with the Horatian maxim: " Naturam expellas furca, tamen usque recurret." Mr. Madison reared, with great care, a young hawk, which, for a long time, associated with the young of the poultry, without exhibiting the slightest carnivorous or migratory propensity; until, on one occa- sion, whilst some of his friends were admiring its state of domestica- tion, it suddenly arose in the air, darted down, and seized a chicken, with which it flew to a neighbouring tree, and, after it had finished its repast, took flight, and was never seen afterwards. Instinct, then, is possessed by every organized body, animal and vegetable; whilst intelligence is the attribute of those only that are endowed with a certain nervous developement. The two are, there- fore, manifestly distinct;—the former predominating over the latter in the lower classes of animals; whilst, in the upper classes, intelligence becomes more and more predominant, until, ultimately, in man, it is so ascendant as to appear to be the main regulator of the functions ; indeed, some have altogether denied the existence of instinct in him. Instinct is seated in every part of a living body ; is totally independ- ent of the nervous system; occurs in the vegetable and the zoophyte unprovided with nerves, or at least in which nerves have never been discovered; whilst intelligence is always accompanied by a nervous system, without which, indeed, its existence is incomprehensible. How can we, consequently, accord with those physiologists who place the seat of instinct in the organic nervous system, or in the reflex or ex- citory motory system of nerves; and that of intelligence in the brain ? Where is the organic nervous system of the zoophyte, and a fortiori of 1 Good's Book of Nature, 3d edit., ii. 107, Lond., 1834. 2 Rev. Sydney Smith, op. cit., p. 243. 710 LIFE. the vegetable? Or how can we admit the seat of the various instincts to be in the encephalon, seeing that we have them exhibited where there is neither encephalon nor anything resembling one ! The ace- phalous foetus undergoes its full developement in other respects in utero, with the same regularity as to shape and size as the perfect foe- tus ; and can we deny it the existence of instinct ? Yet, in the upper classes of animals especially, many of the manifestations of instinct are effected through the nervous system, which, in them, as we have elsewhere seen, seems to hold in control the various functions of the frame, and to be one of the two great requisites for the existence of vitality. The instinctive action in the appropriate organ, which gives rise to the internal sensations of hunger, thirst, &c, is communicated to the great nervous centres by the nerves ; the encephalon responds to the impression, and excites, through the medium of the nerves, the various organs into action which are calculated to accomplish the monitions of the instinct. What is the nature of this instinctive force ? Of this we know no more than we do of the nature of life, of which it is one of the manifestations. It is equally inscrutable with the imponderable agents, light, caloric, electricity, and magnetism, or with the mode of existence of the immaterial principle that gives rise to the mental phenomena. We see it only in its results, which are, in many cases, as unequivocal as those produced by the agents referred to. All, perhaps, that we are justified in concluding is—with Dr. Good—"that instinct is the operation of the principle of organized life, by the exercise of certain natural powers, directed to the present or future good of the individual, whilst reason is the operation of the principle of intellectual life, by the exercise of certain acquired powers directed to the same object;— that the former appertains to the whole organized mass as gravitation does to the whole unorganized; equally actuating alike the smallest and the largest portions; the minutest particles and the bulkiest sys- tems ; and every organ, and every part of every organ, whether solid or fluid, so long as it continues alive;—that, like gravitation, it ex- hibits, under particular circumstances, different modifications, different powers, and different effects; but that, like gravitation, too, it is subject to its own division of laws, to which, under definite circumstances, it adheres without the smallest deviation ; and that its sole and uniform aim, whether acting generally or locally, is that of perfection, preser- vation, or reproduction."1 In this view, reason demands discipline, and attains maturity: instinct, on the contrary, neither requires the one, nor is capable of attaining the other. It is mature from the first, and equally so in the infant as in the adult.2 The great cause of those mysterious phenomena, that characterize living bodies, and distinguish them by such broad lines of demarca- tion from the dead, has been a theme of anxious inquiry in all ages; and has ever ended in the supposition of some special abstract force, to which the epithet vital has been assigned, and which has received various appellations. Hippocrates designated it by the terms v<«$, and 1 See an interesting chapter on Instincts and Habits in [Sir] Henry Holland, Chap- ters on Mental Physiology, p. 20U, London, 1852. ' Op. cit., p. 155. VITAL PROPERTIES. 711 evo^juwv ; Aristotle styled it the animating or motive and generative prin- ciple; Van Helmont, archozus; Stahl, anima; Barthez, and Hunter, vital principle, ke. ke. Yet, as Dr. Barclay1 has observed, all physio- logical writers—ancient and modern—seem to be agreed, that the causes of life and organization are utterly invisible, whether they pass under the name of animating principles, (Aristotle, Harvey, &c.,) vital principles, (Barthez,) indivisible atoms, spermatic powers, organic par- ticles or organic germs, (Buffon,) formative appetencies or formative propensities, (Darwin,) formative forces, (Needham,) formative nisus or Bildungstrieb, (Blumenbach,) pre-existing monads, (Leibnitz,) semina rerum, (Lucretius.) plastic natures, (Cudworth), occult qualities, or certain unknown chemical affinities. " All seem agreed, that what- ever they be, they have been operating since the world began, and throughout the world operating regularly, without intermission, in various places at the same time. All seem agreed, that their modesof operation are strictly methodical; that they seem to act on definite plans, and actually exhibit specific varieties of chemical combination, and mechanical structure, which human intelligence cannot compre- hend, much less explain. From their mutual dependence and other relations subsisting between them, all seem to speak as if they were subject to one great cause, which regulates and harmonizes the whole. All seem to speak of this great cause as if it were eternal, omnipotent, omnipresent; whether it be the element of fire, of air, or of water, or whether it be fate, nature, necessity, or a God." By virtue of this principle or force of life,—the Mod of Baron von Eeichenbach2—every organized tissue is possessed of certain properties, to which the term vital has been assigned. Eegarding the precise number of these properties, physiologists are not agreed. Whilst some have reckoned many; others have admitted but one. All the functions which we have hitherto considered, are under the influence of life, and are products of the vital properties seated in the tissues; but we do not consider them to be directly caused by these properties Digestion, for example, is executed by a series of organs, all of which are condu- cive to a certain result—the aggregate constituting the function of digestion. The result of the action of the salivary gland is very differ- ent from that of the liver ; yet both operations are vital, but modified by the different organization of the two glands. We do not ascribe the difference to a difference in the vital properties of the glands, lhese are probably the same in both ; and are seated in the primary tissues, of which all the more compound textures and organs are built up. 1 Hey are primary or fundamental properties of living matter. Stahl having observed obscure, oscillatory movements alternate contraction and expansion in certain parts of the body, either during the exercise of a function, or on the application of some external agent, conceived, that every part of the frame is, at all times, more or less susceptible of similar movements. These movements he called tonic; > An inauirv into the Opinions, ancient and modern, concerning Life and Organiza- tion, p. 519, EdSb., 1S22; and The Muscular Motions of the Human Body, p. 261, ^iws^-'Physiological Researches on the Dynamics of Magnetism, Electricity Heat, LigMi^rystallSon,aand Chemism in their relations to vital force, English edit, by Dr. Ashburner, p. 224, Lond., lboO. 712 LIFE. their effect upon the organs tone, and the property by which they were induced he esteemed peculiar to organization, and called tonicity. This vital property, he conceived, influences the progression of the fluids in the vessels; the phenomena of exhalation and absorption ; and is totallyf distinct from the properties possessed by inorganic bodies. Haller1 admitted two vital properties, very different from each other, which seemed to him to be equally elementary. By the one of these a living part exhibits itself to be sensible, or transmits to the sensorium an impression made upon it either by an extraneous body, or by its own internal and organic action; by the other, a part contracts in a manner appreciable to the senses, either by the influence of the will, or of some external or internal stimulus. The first of these he con- sidered to be a special vital property, which he termed sensibility; and the second to be another, which he called irritability. Prior to his time the word irritability had been adopted by Glisson,2 who had noticed the fact that living matter is acted upon by irritants of various kinds in a mode no wise analogous to physical and chemical motions; and hence he concluded, that every organ of the human frame possesses an inherent and peculiar force, which presides over its movements, and is requisite for the exercise of its functions. This force he called irrita- bility. De Gorter3 subsequently extended the views of Glisson, and applied them to the vegetable, affirming irritability to be the sole vital property of all organized bodies, vegetable as well as animal. The acceptation, given to the term by Haller, was consequently more limited. He restricted it to those motions of parts that fall under the observation of the senses;—such as the contraction of the voluntary muscles, heart, &c. He made numerous experiments on living animals, for the purpose of discovering what parts are possessed, and what are not, of the true properties of sensibility or irritability, and he concluded, that the former resides exclusively in the nervous,—the latter in the muscular, system. Dr. Marshall Hall4 still employs the term in the restricted sense of Haller. This celebrated theory, which formed so large a part of physiological science at one time, and is still- an interesting topic to the physiologist, has been referred to in so many parts of this work as to require but few comments here. We have seen, that many parts, regarded by Haller as insensible, are acutely sensible in disease; and that we can- not pronounce a part to be positively insensible, until we have applied every kind of irritant to it without effect. We have elsewhere defined sensibility to be an exclusive property of the nervous system; and have attempted to show, that irritability is a property of the muscular tissue—a vis insita—totally independent of the nerves, but of which the nervous fluid is an appropriate excitant. As, however, the vital properties of sensibility and irritability were restricted by Haller to the nervous and muscular systems, they were regarded to be insufficient for the explanation of the various living actions of the frame: the 1 Element. Physiol. ; and Memoire sur la Nature Sensible et Irritable des Parties du Corps, Lausan., 1756. 2 De Ventriculo, in Manget. Bibl. Anatom.,i. 80, Grenev.,1699. 3 Medicin. Compendium, Lugd. Bat., 1742. 4 Art. Irritability, Cyclop, of Auat. and Physiol., July, 1840. VITAL PROPERTIES. 713 next step was to extend them to every part and to every tissue. It was found, for example, that on investigating the most minute move- / ments of parts, these movements were always preceded by an impres- sion, to which they seemed sensible, and which appeared to excite their actions. This general property, common to every living part, of receiving an impression, was called sensibility;—thus generalizing the property, which Haller had restricted to perceptivity by the mind. Every part was said to be sensible to the blood sent to it for its nutri- tion. Again, every part was observed to move in consequence of the impression it received, sometimes in an apparent manner, as the heart; at others, too slightly for its movements to be recognized otherwise than by the results,—as in the case of the glandular organs; but always in a manner special to organized matter, and not analogous to any physical or chemical process. This motion was, therefore, referred to another force called motility, which was nothing more than irritability generalized. These two properties are alone admitted by most modern writers. Every organ is said to feel and to move, after its manner, in the performance of its function;—the stomach in digestion; the heart in propelling the blood; the muscle in contracting, and the nerve in transmitting sensitive impressions to the brain. Many modern physiologists, whilst they adroit the vital properties of sensibility and motility, have reckoned a greater number: thisis owing to their having observed, that each part has its own peculiar mode of sensibility and motility; and when these modes have seemed to differ largely from each other, they have elevated them into so many special vital properties. The chief modern theories on the vital pro- perties are those of Barthez, Blumenbach, Chaussier, Dumas, and Bichat. M. Barthez1 admitted five, which we can do no more than enumerate,—sensibility, force of contraction, force of expansion or active dilatation, force of fixed situation, and tonicity. Blumenbach2 also admit- ted five-sensibility, irritability, contractility, vita propria or proper force of life, nisus formativus—force of formation or B i 1 d u n g s t r i e b. M. Dumas3 referred all the living phenomena to four vital properties; sen- sibility, motility, force of assimilation, and force of vital resistance. The theory of Bichat4 on this subject requires a more detailed notice. He, also, admitted five vital properties; organic sensibility, insensible organic contractility, sensible organic contractility, animal sensibility, and animal contractility. First. Organic sensibility is the faculty possessed by every living fibre of receiving an impression, or of being modified by con- tact, the modification being restricted to the part that experiences it, and'not transmitted to the brain. The term sensibility was adopted by Bichat because already established: and the epithet organic was added to affirm that it is the exclusive attribute of organized bodies, and common to all. This property is not only modified in each organ—as the difference in their nutrition and functions demonstrates—but it adapts each organ to its appropriate external excitant, so that the sah- 1 Nouveaux Elemens de la Soienoe de l'Homme, Paris, 1806. 2 Institutions Physiologic*, Gotting., 17S6 ; or Elliotson's translation. 3 Principes de Physiologie, 2de edit., Paris, 1806. « Anatomie OCnerale, torn. i.; and Recherches Physiologiques sur la Vie et la Mort, Paris, 1800. 71-1 LIFE. vary gland shall be specially influenced by mercury; the upper part of the small intestine by calomel; the lower by aloes, ke. ke. Its exercise is continuous, involuntary, known only by its results, and is more marked as we descend in the scale of animal life; whilst animal sensibility is the contrary. Secondly. Insensible organic contractility is the faculty possessed by every living part, of moving in an impercep- tible manner, in consequence of an impression immediately received, without either the mind having consciousness of the motion, the will participating, or the brain in any manner directing it. We have an example of this in the action of the stomach during digestion; and of every part of the body on the blood sent to it for its nutrition. Bichat applied the term insensible organic contractility to this property, for the following reasons:—contractility, because contraction is the kind of motion which constitutes it; organic, because it is common to all living beings; and insensible, because the brain has no consciousness of it. Like organic sensibility, it is modified in each organ. Its exercise is likewise continuous and involuntary ; and it also exhibits itself more intensely as we descend the scale of beings. It always co-exists with organic sensibility. Thirdly. Sensible organic contractility is the same motive faculty as the last, with this difference, that the movements induced by it fall under the senses, and are recognized independently of their results. This property is likewise modified in each organ; its exercise is also involuntary, and it only differs from the last in degree, —the movement that constitutes it being apparent. Thus, the heart contracts independently of the will, but its motions are not impercep- tible, as in the cases which belong to the second vital property—insen- sible organic contractility. Fourthly. Animal sensibility is the property possessed by certain organs of transmitting to the mind, through the medium of the brain, the consciousness of impressions, which they have received. It is sensibility in the restricted acceptation of Haller. The epithet animal was given to it by Bichat, to distinguish it from the other variety of sensibility, which belongs to all organized bodies, whilst this is exclusively possessed by animals. The whole of the attri- butes of this property have been detailed at much length in another portion of this work. Fifthly. Bichat admitted a fifth vital property, under the name animal contractility, which comprised voluntary mus- cular contraction;—treated of elsewhere in this volume, as one of the functions of the body. It differs from organic contractility in its ex- citing causes not being seated in the organ in which it is developed,— that is, in the muscles,—but in the brain; and, moreover, whilst other varieties of contractility are irresistibly connected with, and propor- tioned to, the kind of sensibility correspondent to them, such is not the case with animal sensibility, and its play is never continuous. From the distinction we have endeavoured to draw between the fun- damental vital properties and the functions, it will be obvious that the ingenious division of Bichat is susceptible of farther curtailment by analysis. A vital property must be one possessed by all living bodies; it is fundamental in the tissues, and differs according to the precise structure of the tissue. It is found in the vegetable as well as in the animal. Neither of the last two properties of Bichat, however, corre- sponds with this definition. They do not exist in the vegetable. They VITAL PROPERTIES. 715 require not only a nervous system, but a brain, that can conceive and will. They are both, indeed, complicated functions, and, as such, have been considered at great length elsewhere. By ultimate analysis, there- fore, the five vital properties of Bichat may be reduced to "two,—sen- sibility and motility. Perhaps we ought to rest satisfied with the admission, that every primary tissue is capable of being acted upon by appropriate stimuli or is sensible; and that it possesses the additional property of moving in consequence of such impression. Physiologists have, however, attempted to simplify the subject still farther, and to reduce the vital properties to one only. Such is the view of M. Brous- sais, who considers contractility to be the fundamental vital property of all the tissues. Adelon considers, that sensibility, which must carry with it the idea of motion, and is the active, motive faculty of living matter, is the only living property that should be admitted. The term sensibility is not, however, unexceptionable, in consequence of its being often used exclusively to convey the notion of mental or conscious perception, and of such acceptation having been received into physio- logy to designate a function. It has, consequently, been proposed to substitute the term excitability, incitability or irritability, but with the same signification. Rudolphi1 prefers incitability, (Erregbarkeit,) as not liable to the objection that may be urged against the others, of having been employed in other significations. This incitability differs in the different organs and tissues; in the muscles he terms it irrita- bility (Muskelkraft, Reizbarkeit); in the nerves, sensibility (Ner- venkraft, Empfindlichkeit); and by some physiologists, in the membranous parts, it is called contractility (Spannkraft, Zusam- menziehungskraft). It has generally been considered, that the cessation of irritability in a tissue indicates its positive death; yet experiments have sufficiently shown, that the vital property can be restored. Dr. Kay2 had found, that if blood be injected into the vessels of a dead animal, immediately after irritability has disappeared, the vital property will re-appear. Dr. Brown-Sequard3 has shown, that in this way the vital property of nerves and muscles may be restored in limbs which have lost their irritability and been rigid even for hours. He tied the aorta imme- diately behind the origin of the renal arteries in several rabbits. Short- ly afterwards, sensibility and the voluntary movements disappeared in the posterior limbs. He waited until muscular irritability had given way to cadaveric rigidity, and when this had lasted twenty minutes, he relaxed the ligature; circulation took place, and sensibility and voluntary movements re-appeared. Hence he infers, that not only local life* but all the properties and actions of full life can be restored in limbs that have been in the state called rigor mortis, cadaveric or post-mortem rigidity. The conclusions of Dr. Brown-Sequard, from all his experiments on the subject on decapitated men and animals, are:—that first, red blood, that is, richly oxygenated blood (arterial or venous) is able to revive ' Grundriss der Physiologie, ler Band., S. 247, Berlin, 1821. 2 The Physiology, Pathology and Treatment of Asphyxia, p. 14d, London, ibchl. 3 Medical Examiner, May, 1353, p. 280. 716 LIFE. irritability in muscles, four or five hours after these organs have lost their property. Secondly. Bed blood is able to revive the vital pro- perties of nerves and nervous centres, when these properties have not been lost for more than about an hour. Thirdly. Muscular irritability can be maintained for more than forty-one hours, by mere injections of blood, in limbs separated from the body of a rabbit. Such are the phenomena that indicate the existence of a vital force, and such the laws by which it seems to be governed. By certain physi- ologists it is considered to influence solids only: by others, it has been considered to reside in the fluids also, and especially in the blood. The notion of the vitality of this fluid was espoused by John Hunter,1 and to him we are indebted for many of the facts and arguments brought forward in its favour, which have impelled the generality of modern physiologists to admit its existence. The analogy of the egg had de- monstrated that life is not restricted to substances which are solid and visibly organized. The fresh egg, like other living bodies, possesses the ordinary counteracting powers communicated by vitality, and resists those agents that act on the dead egg as on other animal sub- stances deprived of the living influence. The fresh egg may be ex- posed for weeks, with impunity, to a degree of heat that would inevit- ably occasion the putrefaction of the dead egg. During the time of incubation, the egg of the hen is kept for three weeks at a heat of 105° ; yet when the chick is hatched, the remaining yolk is perfectly sweet. The power of resisting cold is equally great. Dr. Hunter per- formed several experiments, which show the influence of the vital force in resisting cold, and of cold in diminishing the energy of the force. He exposed an egg to the temperature of 17° and 15° of Fahrenheit, and found that it took about half an hour to freeze. When thawed, and again exposed to a temperature of 25°, it was frozen in one-half the time. He then put a fresh egg, and one that had previously been frozen and again thawed, into a cold mixture at 15° ; the dead egg was frozen twenty-five minutes sooner than the fresh.2 These experiments led to the legitimate inference, that the former possessed the force of life, and, although fluid, must have enjoyed the properties which we have described to be characteristic of vitality,—of being acted upon by an appropriate irritant, and of moving responsive to the irritation. Simi- lar results to those obtained with the egg followed analogous experi- ments with the blood. On ascertaining the degree of cold, and the length of time necessary to freeze blood taken immediately from the vessel, he found that, as in the egg, a much shorter period, and a much less degree of cold, were requisite to freeze blood that had been pre- viously frozen and thawed, than blood recently taken from the vessel. The inference deduced from this was, that the vitality of recent blood being comparatively unimpaired, it was enabled to resist cold longer than blood whose vital energy had already been partly exhausted by previous exposure. It would appear, however, that the vital force in fish can resist the action of frost. Those that were caught by Captain Franklin's party in Winter Lake froze as they were taken out of the 1 Treatise on the Blood, &c, p. i., ch. i. 2 Philosoph. Transact., 1778. pp. 29, 30. LIFE OF THE BLOOD. 717 nets, and became in a short time a solid mass of ice; yet when thawed they were alive.1 The fluidity of the blood whilst circulating in the vessels has been regarded as an additional evidence of its vitality. It is obvious, that such fluidity is indispensable, seeing that it has to circulate through the minute vessels of the capillary system, and that the slightest coagulum forming in them would lead to morbid derangement. Yet the blood is, by its constitution, peculiarly liable to become solid, and whenever it is removed from its vessels it coagulates. This is not owing simply to the cessation of circulation, for if it be kept at the same temperature as in the living body, and be made to circulate with equal rapidity through a dead tube, it equally becomes solid. The cause, consequently, that maintains its fluidity, is the vital agency; or, as J. Miiller remarks, the proper combination of its elements is main- tained so long only as it is under the influence of living surfaces,— that is, of the vessels. The experiments of Schroder van der Kolk2 show, that coagulation takes place with extraordinary rapidity after the brain and spinal marrow have been broken down; even in a few minutes after the operation, coagula -were found in the great vessels. Mayer observed, that after the application of a ligature to the pneu- mogastric nerve the blood coagulated in the vessels, and death was produced. Sir Astley Cooper, on repeating the experiment, found, that the conversion of venous into arterial blood in the lungs was pre- vented. Of four experiments, however, which were performed under the direction of J. Miiller,3—two on dogs and two on rabbits — although the animals were examined immediately after death, which resulted from the ligature of the pneumogastrics, in two cases only was a small coagulum, of the size of a pea, discovered in the left side of the heart, and none in the pulmonary vessels. Another argument in favour of the vitality of the blood is drawn from the facts con- nected with its coagulation,—facts which show that the process is but little influenced by physical agents, and wnich have induced M. Ma- gendie4 to infer, with many other physiologists, who are but little dis- posed to invoke the vital agency, " that the coagulation of the blood cannot be ascribed to any physical influence, but must be esteemed essentially vital, and as affording a demonstrative proof, that the blood is endowed with life." It has, indeed, been attempted to show, that there are certain phenomena, which demonstrate that the vitality of this fluid increases or diminishes with the vitality of other parts of the body. When blood is drawn from a vessel it does not instantly co- agulate or die; and, by observing the length of time consumed in the process, it has been thought that we might, in some measure, be able to estimate the degree of vital energy it possesses. In diseases where the vital action is exalted,—as in inflammation,—the blood is fotmd to coagulate more slowly than in a state of health, and the coagulation ' See page 595 of the first volume. . * Comment, de Sanguin. Coagulat., Groning., 1820; and Diss sist. Sangum. Coagu- lat., Groning., 1820, cited in Miiller, Handbucb u. s. w., Baly s translation, p. 97, Lon'd.,18:'8r ' 3 Qp cjt p. 9S. * Pr-'cis de Pbvsiologie, 2M X p, u o a a to, 3 © % bo "3 o .s 3 o 0> d rrj 60 Si O _ 0 d 0 0 v. • 1° a J2 *5 3 a a o> "3 S > 1 3 ? 2 1 . ■s. e3 £S>.g - fi. si 03 a 5 0 ~ 0 a a < a w o fid .2 o S'5 7 ii 5 s s s OS i-! bo VIII. D rative childbi 13 2 0 v. w /. 7 Alabama 9.091 3,029 63S 676 1,174 34 709 36 151 41 176 616 1,791 Arkansas 3,021 1,358 122 144 396 6 254 5 62 13 2 39 132 7 4 si California 905 659 9 13 15 6 1 1 2 38 161 Columbia, Dist. of 846 2S9 34 89 197 i2 37 '2 ii 8 1 29 33 104 Connecticut 5,781 1,987 457 517 1,293 106 195 26 41 39 4 356 240 *7 513 Delaware 1,209 461 82 113 190 5 63 1 10 8 28 40 208 Florida 931 307 97 51 108 8 114 3 21 3 '2 25 76 2 114 Georgia 9,923 3,136 912 474 1,334 33 872 31 199 53 16 248 663 29 1,925 Illinois 11,759 5,858 433 712 1,799 32 411 41 167 60 11 107 332 4 1,792 Indiana 12,708 6,331 612 905 1,824 37 414 42 137 64 31 182 361 33 1,835 Iowa 2.041 954 83 147 376 3 67 4 26 6 5 13 100 1 259 Kentucky 15,033 6,895 852 878 2,1011 68 588 50 141 75 20 306 569 17 2,473 Louisiana 11,95(3 5,999 621 861 1,175 50 781 18 135 36 13 170 599 15 1..J7S Maine 7,584 2,654 498 492 2,077 76 292 35 58 36 46 310 302 ■• 70s Maryland 9,621 3,345 496 855 1,792 129 405 22 109 70 11 278 332.17 1,760 Massachusetts 19,404 7,189 1,627 1,296 4,418 335 1,065 59 209 85 66 792 657!24 1,5S2 Michigan 4,515 1,428 388 483 1,0811 30 157 25 74 26 23 109 195 4 492 Mississippi 8,721 3,639 509 570 1,0911 45 732 21 130 38 9 126 601 10 1,200 Missouri 12,292 6,832 447 649 1,344; 37 555 15 149 56 8 101 371 7,1,721 New Hampshire 4,231 1,582 302 333 1,072 89 140 21 30 27 2 279 146 .. 208 New Jersey 6,465 2,512 431 667 1,201! 72 268 17 58 51 8 272 231 4 673 New York 45,600 17,976 3,633 4,492 8,913 549 1,906 182 358 262 68 1,393 1,633 51 4,184 North Carolina 10,165 2,495 1,010 527 1,728 28 620 63 188 67 14 40!) 596:20 2,393 Ohio 28,957 16,138 1,265 1,809 4,025 137 836 92 221 119 29 506 707| 6 3,067 Pennsylvania 28,551 11,645 1,919 2,824 5,055 323 957 121 365 193 28 928 951 33 3,206 Rhode Island 2,241 780 164 222 572 31 60 2 15 10 7 97 101il7| 163 South Carolina 8,047 2,645 678 467 1,343; 30 755 15 150 47 15 263 403 11 1,225 Tennessee 11,875 4,524 733 628 l,493l 34 542 42 131 85 26 316 570 29 2,720 Texas 3,057 1,285 150 159| 377 11 180 3 73 13 2 34 204 6' 560 Vermont 3.129 951 258 267, 886 67 100 16 24 11 3 210 93. l! 242 Virginia 19,059 5,190 1,427 1,249 3,567 103 925 83 312 133 17 867 942,15,4,229 Wisconsin 2,903 1,242 177 228j 541 12 129 7 47 24 1 29 123' 343 , . fMinnesota 29 12 2 3| 4 .. 3 2 .. 3 *C 8 J New Mexico 1,157 335 120 19 165 2 31 32 10 2 26 67'... 348 <» '| ] Oregon 47 23 1 2 6 1 4 1 1 1 3j.. 4 H- LUtah 239 149 10 12 35 .. 5 i 1 'S 9.. 1 16 The diagram, Fig. 532, from M. Quetelet,2 exhibits the relative via- bility of the two sexes as deduced by him from numerous statistical inquiries. The dotted line represents the viability of the female: the other that of the male. According to this, the maximum of viability is at the age of 14 in both sexes. After puberty, it diminishes more rapidly in the female than in the male. It is also less during the pe- riod of childbearing, from the 27th to the 45th year. The age of 1 Mortality Statistics of the Seventh Census of the United States, 1850: embracing, 1. The cause of death. 2. The age and sex. 3. The colour and condition. 4. The nativity. 5. The season of decease. 6. The duration of illness. 7. The occupation of the persons reported to have died in the twelve months preceding the first of June of that year ; with sundry comparative and illustrative tables. By J. D. B. De Bow, Superintendent United States Census, p. 11, Washington, 1855. 2 Sur l'Homme, &c, English edit., p. 32, Edinb., 1843. PHENOMENA OF DEATH. 731 shortest viability is immediately after birth; that of the longest via- bility immediately before puberty. The viability of the child after the first month of existence, according to M. Quetelet^ is greater than that of the man nearly 100 years old. Towards the 75th year, it is scarcely greater than that of the infant about the sixth month after birth. For some time before dissolution,—both in death from old age and from disease,—the indications of the fatal event become more and more apparent. The speech grows embarrassed; the ideas are incoherent; the hands, if raised by the effort of the- will, fall inertly into their former position; the laboured respiration occasions insufficient hsema- tosis, and the distress excites an attempt at respiration, which the de- bility renders nearly ineffectual; distressing yawnings and gaspings occur to remedy the defective pulmonary action, and the whole respi- ratory system is in forcible and agitated motion,—the teeth, at times, gnashing, and convulsive contractions occurring at the corners of the mouth. The heart becomes gradually unable to propel the blood with the necessary force into the arteries, so that the fluid ceases to reach the extremities of the body—the hands, feet, nose, and ears—which Fig. 532. a t> 10 IS 20 25 30 UO SO 60 10 80 90 V Curves indicating the Viability or Existibility of Male and Female at Different Ages. become frigid, and a cold clammy moisture oozes from the vessels. In experiments on animals, the blood is found to be gradually driven no farther than to the feet; then to the groin; afterwards it reaches only to the kidneys, and a kind of reflux occurs through the space along 732 DEATH. which it had previously been urged forwards. The flux and reflux now reach no farther than the diaphragm, and gradually retreat, until the blood flows back upon the heart itself, which now stops for a time, and then makes an effort to free itself from the contained fluid. The heart's action and respiration are imperfectly performed for a few times at irregular intervals, until at length the contractility of the organ is entirely gone. Bespiration ceases by a strong expulsion of air from the chest,—often accompanied by a sigh or a groan, and probably arising in part from the relaxation of the inspiratory muscles, but still more from the elasticity of the cartilages of the ribs. Hence it is that, in common language, to expire is synonymous with to die. In cases of sudden death, the heart may continue to beat for a while after inner- vation and respiration have ceased. For some time immediately preceding dissolution, there is usually a peculiar mixed expression of countenance,—a compound of apparent mental and corporeal suffering,—which has given occasion to its being called "the agonyP It is characterized by facial indications, that were first well described by Hippocrates, and from him called Fades Hippocratica. The nose is pinched; the eyes are sunken; the temples hollow; the ears cold and retracted; the skin of the forehead is tense;' the lips are pendent, relaxed, and cold. The eye, during this con- dition, especially when dissolution approaches, is fixed and slightly elevated, being kept in that position, according to Sir Charles Bell, by the power of the brain over the voluntary muscles of the eye being lost, and. the organ being given up to the action of the oblique, which he considers to be involuntary muscles. The word " agony," applied to this condition, means in many languages a violent contest or strife, but its acceptation has been extended so as to embrace what have been termed the " pangs of death," and any violent pain. This agony of death, however, physiologically speaking, instead of being a state of mental and corporeal turmoil and anguish, is one of insensibility. The hurried and laboured breathing; the peculiar sound on inspira- tion, and the fixed and turned up eyeball, instead of being evidences of suffering, are now admitted to be signs of the brain having lost all, or almost all, sensibility to impressions. All the indications of mortal strife are such in appearance only; even the convulsive agitations, occasionally perceived, are of the nature of epileptic spasms, which we know to be produced in total insensibility, and to afford no real evidence of corporeal suffering. Although, from the moment that respiration and circulation perma- nently cease, the body may be regarded as unquestionably dead, vital properties remain in some of the organs, the presence of which is an evidence that vitality had previously and recently existed. The func- tions, which persist after the animal has become dead to surrounding objects, are those that belong to the organic class. Absorption is said to have occurred after death, and the beard and hair to have grown. To a certain degree this growth is possible, in parts which, like the pileous system, are nourished by imbibition; but the apparent elonga- tion of the hair may be, in part at least, owing to the shrinking of the integuments. The rectum is very frequently evacuated after dissolu- tion; and cases have occurred where a child has been born by the POST-MORTEM HEAT. 733 contraction of the uterus after the death of the mother. The most marked evidence, however, of the continuance of a vital property after dissolution, is in the case of the muscles, which, as we have mentioned in another place, can be made to contract powerfully on the applica- tion of an appropriate stimulus, even for hours after death. Nys- teu,1 from his experiments, inferred, that the parts cease to con- tract in the following order:—the left ventricle, large intestine, small intestine, stomach, bladder, right ventricle, oesophagus, iris, different voluntary muscles, and, lastly, the auricles, particularly the right auricle. The body cools gradually at the surface, and especially towards the extremities. In many cases, however, instead of gradually cooling, the temperature actually rises. Dr. John Davy2 had noticed, that after death from fever, the thermometer, placed under the left ventricle of the heart, indicated, in one case, a temperature of 113°; but the tem- perature before death was not noted, and he was induced to believe, that the elevated temperature was generated before death, and "proba- bly in the same way as the ordinary degree of animal heat, experienced in health, or the extraordinary degree witnessed in febrile diseases." Experiments, however, by Dr. Bennet Dowler,3 of New Orleans, have satisfactorily shown, that the increased production of heat, which he noticed in yellow fever cases, occurs after the cessation of respiration and circulation, and only ceases with the putrefactive process. In one case, for example, the highest temperature during life was in the axilla, 104°; ten minutes after death it was 109° in the axilla; fifteen minutes afterwards, it was in the thigh 113°; in twenty minutes, the liver gave 112°; in one hour and forty minutes, the heart 109°,—the thigh, in the old incision, 109°; and in three hours after removing all the viscera, a new incision in the thigh gave 110°. It is curious, that the maximum of observed heat after death was in the thigh. The follow- ing table by Dr. Dowler exhibits the highest amount of temperature noted in eight different regions in different subjects. It appears from Dr. Davy, Dr. Dowler, and Dr. Benjamin Hensley, jr." who instituted some observations at the Philadelphia hospital, at the request of the author, that the brain produces less heat after death than the contents of the other splanchnic cavities. The bearing of 1 Recherches de Physiologie et de Chimie Pathologiques, Paris, 1811. 2 Researches Physiological and Pathological, Amer. edit., p. 328, Philad., 1840. s Medical Examiner, June, 1845, cited from Western Journal of Medicine and Sur- gery, June and October, 1844. *' .Medical Examiner, March, 184b, p. 149. 734 DEATH. these phenomena on the explanation of calorification has been noticed elsewhere. Another remarkable phenomenon, noticed by Dr. Dowler1 in yellow fever subjects especially, "which are incomparably the best for study," is what he has termed " post-mortem contractility." Numerous ex- periments were performed by him on bodies, that had been dead from a few minutes to several hours, in which the muscles of the extremi- ties, struck with a cane, billet of wood, the hand, or the side of a hatchet, contracted with sufficient force to move a weight of several pounds, and he found, that if several blows on the same spot followed each other rapidly, there was but one contraction, but they exhausted the contractile function more than a single blow; " and if the force be greatly augmented the contractility may be killed, almost imme- diately in the muscle struck, without impairing the action of any other part." Spontaneous movements of the limbs have frequently been observed in persons who have xlied from cholera.2 Whilst the refrigeration of the body is going on, the blood remains more or less fluid; and owing to the arteries emptying themselves, by virtue of their elasticity, of their contained blood, it generally accumu- lates in the vense cavse, auricles of the heart, and vessels of the lungs. By virtue of its gravity, it collects also in the most depending parts, occasioning cadaveric hypersemia, suggillations or livid marks, which might be mistaken for bruises inflicted during life; but may generally be distinguished from them by attention. It will be readily understood, that the situation of the blood in the vessels may differ somewhat accord- ing to the vital organ which first ceases its functions. If the action of the right heart stops, the lung may be empty; if the lung or left heart ceases, the lung and right side of the heart—with the vessels commu- nicating with it—may be surcharged with blood, whilst the organs of the corporeal circulation may be almost empty. During the progress of refrigeration, and especially soon after death, the muscles are soft and relaxed, so that the limbs fall into the position to which the force of gravity would bring them; the eyes are half open; and, according to a recent writer, M. Rippault3—the iris is perfectly flaccid when the globe of the eye is compressed in two opposite directions; and if the person be alive the pupil will retain its circular form notwithstanding the compression; whilst if dead, the aperture becomes irregular and the circular form is lost; the lips and lower jaw are pendent, and the pupil dilated. When the body, however, is cold, the blood is coagu- lated, and white or yellowish coagula exist in the right heart, which were at one time supposed to be morbid and termed polypi. They take the shape, more or less, of the cavity in which they are found. Lastly, the muscles become firmly contracted, so that no part can be moved without the application of considerable force; and, in this state, they continue until the natural progress towards putrefaction again 1 Experimental Researches on the Post-mortem Contractility of the Muscles, with Observations on the Reflex Theory, reprinted from the New York Journal of Medicine, for May, 1846. 2 See Dr. Brown-Sequard, on Spontaneous Rhythmical or Irregular Contractions in Muscles after death, in Medical Examiner, p. 493, August, 1853. 3 Cited in London Medical Gazette, May, 1846. SIGNS OF DEATH. 735 softens their fibres. This has been regarded by some physiologists as arising from the last exertion of that residue of vital power, which the body retains after the period of apparent dissolution. With more propriety, perhaps, the rigor mortis may be assigned to physical altera- tions taking place in the organs, owing to the total loss of those powers, which were previously antagonistic to such c-hanges. It has been attributed, by M. Brucke,* to the coagulation of the liquids in the interior of the tissues. He considers, that the fibrin of the muscle coagulates, when the muscular fibre is deprived of life. By some, the muscular contraction, which gives occasion to the rigor mortis, is held to be of the same kind as that which takes place under the influence of the nervous stimulus, although differing as to its conditions. When very strong, it renders the muscles prominent, as in voluntary con- traction ; and Dr. Carpenter2 thinks the comparative observations of Mr. Bowman upon the state of muscular fibre passing into this condi- tion, and upon that which presented various degrees of contraction from ordinary causes, leave no doubt as to their correspondence. The conditions are certainly, however, very different; for the power of the muscle to contract on the application of appropriate stimuli is lost when the rigor mortis sets in. It has also been likened to the coagu- lation of the blood in the vessels; and Dr. Carpenter3 thinks " there is certainly evidence enough to make it appear, that some analogy exists between the two actions, although they are far from being identical. Af- ter those forms of death in which the blood does not coagulate,or coagu- lates feebly, the rigidity commonly manifests itself least, but this is by no means an invariable rule." He thinks it probable, " that as the coagu- lation of the blood is the last act of its vitality, so the stiffening of the muscles is the expiring effort of theirs." Yet—as we have before seeri_the rigor mortis can be removed by the injection of blood into the vessels of the part, which appear rather to be in a state of sus- pended animation, a condition speedily induced by certain agents. Chloroform, for example, injected into the main artery of a limb, in- stantly produces the strongest rigidity, which disappears if blood be allowed to circulate again in it; and M. Brown-Sequard4 has found, that if a limb, into which an injection of chloroform has been thrown, is separated from the body, it is able, under the influence of an injection of blood, to recover its muscular irritability, two, three, four five, and— in one case—ten days afterwards. M. Robin suggests, and M. Brown- Sequard agrees with him, that chloroform prevents the chemical changes that take place in organic bodies after death and thus it can be understood, how an injection of blood may be able to elicit imta- bilitv so long after the limb has been separated from the body. Ine latter named gentleman, however, found, that chloroform does not en- tirely prevent organic change in the muscles, as he found that the lonoir the limbs had been separated from the body, the greater was the°quantity of blood necessary for the reproduction of irritability. * Miiller's Archiv., Nov., 1842; cited in Edinb. Med. and Surg. Journ., Oct., 1843, P* ^Principles of Human Physiology, 2d edit., p. 324, Lond 1844. 3 Principles of Human Physiology, 5th Amer. edit., p. 332, Philad., 1853. * Medical Examiner, May, 1853, p. 28o. 736 DEATH. It might seem from the previous enumeration of the signs of death that no difficulty could possibly arise in discriminating between a living and a dead body. Cases have, however, occurred, where such difficulty has been great and perplexing. Many of the signs may exist, and yet the person be merely in a state of suspended animation; and in certain instances it has even been considered advisable to wait for the mani- festations of the putrefactive process, before the body should be con- signed to the grave. The following cases, given by Dr. Gordon Smith,1 strongly exhibits the embarrassment that may occasionally occur. A stout young man had been subject to epilepsy, which became com- bined with madness. On this account it was necessary to remove him to a private asylum in the neighbourhood of London, where he died suddenly in a violent epileptic parox}Tsm. The body was removed to the residence of his friends soon after death, when the necessary prepa- rations for interment were made. On paying attention to the corpse it was found, that the limbs Avere pliable; that the eye was neither col- lapsed nor glazed; and that the features retained their full natural appearance as during life. A surgeon, who, for years, had been in the habit of attending him, was sent for; and although he could find no indications of vitality, he prudently recommended, that the interment should not take place until decomposition had began to manifest itself. In the course of two or three days, appearances still continuing the same, a physician was called in, who concurred in the recommendation that had been given. Fifteen days from the supposed time of his death had elapsed, when Dr. Smith's informant had an opportunity of inspecting the body. At this time, the countenance retained the appearance described, but the eye seemed beginning to sink, and some degree of lividity had commenced on the surface of the abdomen. The joints were still flexible. At this time, an eminent professor of anatomy viewed the body, and, considering the hesitation that had prevailed to be altogether groundless, he appointed the following day to examine it internally. The head was accordingly opened, and a considerable extravasation of blood was found in the posterior part of the cranium, between the skull and dura mater, and between the mem- branes and substance of the brain. No serum was detected in the ven- tricles ; but the brain itself was remarkably hard. This was sixteen days after death. On the following day, the body was interred. A clamour now arose amongst the neighbours, that he had been prema- turely handed over to the anatomist. The body was exhumed; an inquest was held; and the evidence of the medical gentlemen demanded. The jury returned a verdict of " apoplexy." It may hence become a matter of medico-legal inquiry to verify the existence of death, in cases where doubt prevails owing to the person being in a state of apparent death,—natural or assumed. The recent observations and experiments of M. Bouchut2 lead him to conclude, that all varieties of apparent death, and especially such as.are owing to syncope and asphyxia, however much their symptoms may differ, pre- sent the common character of the persistence of the heart's pulsation 1 The Principles of Forensic Medicine, 3d edit., p. 540, Lond., 1827. 2 Abeille Medicale, No. 6, Juin, 1548. APPARENT DEATH. 737 audible to auscultation. M. Bouchut's communication was laid before the Academie des Sciences, of Paris, who awarded him a prize for the same; and the commission to whom it was referred reported, through M. Rayer, a great variety of additional observations made by them, which confirm the conclusions of M. Bouchut. He enumerates the cer- tain signs of death under two divisions—immediate and remote. The immediate signs are—prolonged absence of the sounds of the heart; simultaneous relaxation of the sphincters; and sinking of the globe of the eye, with loss of the transparency of the cornea; the first of which is regarded by the commission" as conclusive. The remote sighs are— cadaveric rigidity; absence of muscular contractility under the influ- ence of galvanism, and putrefaction. Yet resuscitation may occur a considerable time after the sounds of the heart have ceased to be audi- ble ; and perhaps the most singular case on record of suspension of two of the most important of the vital functions occurred in the person of John Hunter. In the year 1769, being then forty-one years of age, of a sound constitution, and subject to no disease except a casual fit of the gout, he was suddenly attacked with a pain in the stomach, which was speedily succeeded by apparently a total suspension of the action of the heart and lungs. By a violent exertion of the will he occasion- ally inflated the lungs, but over the heart he had no control whatever; nor, although he was attended, from the first, by four of the chief phy- sicians in London, could the action of either be restored by medicine. In about three-quarters of an hour, however, the vital actions began to return of their own accord, and in two hours he was perfectly re- covered. " In this attack," says one of his biographers—Sir Everard Home—"there was a suspension of the most material involuntary actions: even involuntary breathing was stopped; while sensation, with its consequences, as thinking and acting, with the will, were per- fect, and all the voluntary actions were as strong as ever."1 Dr. Bennet Dowler2 objects to the validity of the tests of M. Bouchut. " Comparative physiology"—he remarks—" shows that an animal may live hours without the heart, and the heart for days without the body. An allio-ator's heart will act with regularity for many hours, perhaps for days, after having been cut out of the body, and emptied of its blood. Let an alligator, thus deprived of its heart, be roasted; return its heart, and apply the stethoscope, and then the dead will afford this certain sign of life. The commission of the Academy cannot object to this argument, because they themselves experimented on the inferior animals in testing M. Bouchut's claims." Dr. Dowler prefers the test of "post-mortem contractility," as he calls it Yet we have seen that after the muscular contractility has been lost, it may be restored by injections of oxygenated blood into the vessels of A^one period it was universally credited, that substances could be administered which might arrest the vital functions, or cause them to > OHIpv's Life of John Hunter, Bell's Med. Lib. edit., p. 38, Philad., 1839 ; and Hun- ter On the miod by Palmer, Bell's edit., p. 189, Philad, 1840. In the latter work, Mr' TTnnter refers to his own case. «' Researches on the Natural History of Death, New Orleans, 1850. VOL. II.—-17 738 DEATH. go on so obscurely as to escape detection. This erroneous popular notion is exhibited in the description of the action of the drug admi- nistered by Friar Lawrence to Juliet. " Take thou this phial, being then in bed, And this distilled liquor drink thou off; When presently thro' all thy veins shall run A cold and drowsy humour, which shall seize Each vital spirit: for no pulse shall keep His natural progress, but surcease to beat". No warmth, no breath, shall testify thou liv'st; The roses in thy lips and cheeks shall fade To paly ashes ; the eyes' windows fall Like death, when he shuts up the day of life; Each part, deprived of supple government, Shall stiff, and stark, and cold, appear like death : And in this borrowed likeness of shrunk death, Thou shalt remain full two-and-forty hours, And then awake as from a pleasant sleep." Romeo and Juliet, iv. 1. Death may be feigned for sinister purposes. When the author was in attendance on the lectures of Mr. Brookes, the distinguished anato- mist of London, a body was brought in a sack to the house, the vital- ity of which was detected by the warmth of a protruded toe. It was that of a robber, who had chosen this method of obtaining admission within the premises. The celebrated case of Colonel Townshend, as well as that of Dr. Cleghorn, referred to elsewhere,1 exhibits the voluntary power occa- sionally possessed over the vital functions, and curious cases are re- lated by Mr. Braid2 of the Fakeers in India, which lead to the belief, that it is possible for the organic actions to be so reduced, that no sign of life may be perceptible for days, and even weeks; and yet that the subjects may be subsequently restored. Some of the cases, given by Mr. Braid, the authenticity of which is vouched for by British officers of high rank in India, would be incredible, without such authority. If believed, they lead to the inference—as Mr. Braid has suggested—that a condition resembling the hibernation of animals is possible in the human subject. In one case, the Fakeer was buried in a subterranean cell, which was well guarded for six weeks: in another, the man had been buried for ten days in a grave lined with masonry, and covered with large slabs of stone; and in another, the experiment was made for three days, under the superintendence of a British officer. In every case, it is affirmed, the body resembled that of a dead person, and no pulsation was perceptible anywhere; yet under the application of warmth to the vertex, and of friction to the-body and limbs, restora- tion was accomplished. Dr. Carpenter3 observes on these strange cases:—" It may be remarked, that the possibility of the protraction of such a state (supposing that no deception vitiates the authenticity of the narratives referred to) can be much better comprehended as occur- ring in India, than as taking place in this country [Great Britain]; since 1 Vol. i. 403. * Observations on Trance or Human Hibernation, London, 1850. s Principles of Human Physiology, Amer. edit., p. 868 (note), Philad., 1855. PHYSIOGNOMY OF THE DEAD. 739 the warmth of the tropical atmosphere and soil would prevent any serious loss of heat, such as must soon occur in a colder climate, when the processes whereby it is generated are brought to a stand." Yet there is reason to believe, that where the organic actions are re- duced to a low point, the absence of heat of a certain degree is desira- able.1 It has been before remarked,2 that fishes, which have been frozen for thirty-six hours, have been resuscitated; and Dr. Kane re- lated to the author some strange, but authentic, cases of restoration amongst the Esquimaux, where persons had been considered dead, and buried in the snow many hours. Lastly, the character of the death, as to violence or gradual extinc- tion, is often exhibited in the physiognomy of the dead. Where it has taken place during a convulsion, or by agents that have forcibly and suddenly arrested respiration or innervation, the countenance may be livid,- the jaws clenched, the tongue protruded and caught between the teeth, and the eyes forced, as it were, from their sockets ; but usu- ally in death from old age, or even from acute and tormenting disease, any distortion or mark of suffering that may have existed prior to dissolution subsides after the spirit has passed, and the features exhibit a placidity of expression singularly contrasting with their previously excited condition. For effect, however, the poet and the painter suit their descriptions of death to the character of the individual whom they are depicting.3 The tyrant falls convulsed and agonized, whilst the tender and delicate female is described to have progressively with- ered, till " At last, Without a groan, or sigh, or glance to show A parting pang, the spirit from her past; And they who watched her nearest could not know The very instant, till the change that cast Her sweet face into shadow, dull and slow, Glazed o'er her eyes—the beautiful, the black,— Oh 1 to possess such lustre, and then lack." Byron's Don Juan, canto iv. Warwick's description of the frightful physiognomy of Duke Hum- phrey after death from suffocation exhibits some of this poetical license:— " But see, his face is black and full of blood ; His eyeballs farther out than when he lived, Staring full ghastly like a strangled man: His hair uprear'd, his nostrils stretched with struggling : His hands abroad displayed, as one that grasp'd And tugg'd for life, and was by strength subdued. Look on the sheets ; his hair you see is sticking; His well-proportioned beard made rough and rugged, Like to the summer's corn by tempest lodged.— It cannot be but he was murdered here : The least of all these signs were probable." King Henry VI., Part n. Act 3. 1 See the observations of Mr. Edwards on asphyxied animals, p. 613 of the first vol- ume of this work. __ t Vol. i. p. 595, and vol. n. p. 71b. s Sir C. Bell, The Anatomy and Philosophy of Expression, 3d edit., p. 185, Lou*. 1844. 740 DEATH. How different is this picture from that of the countenance of the young being, who has gradually sunk to death in the manner above described. The beauty is unextinguished, and the paleness and lividity of death have taken the place of the colours of life; yet the wonted physiognomy may remain :— " Hush'd were his Gertrude's lips! but still their bland And beautiful expression seem'd to melt With love that could not die!" Campbell. Perhaps one of the most beautiful and accurate pictures, drawn by Byron, is his description of the serenity of countenance observable in most fresh corpses; an expression which, by association, is deeply affecting, but not without its consolation to the friends of the de- parted :— He who hath bent him o'er the dead Ere the first day of death is fled ; * * * * Before decay's effacing fingers Have swept the lines where beauty lingers ; And marked the mild angelic air, The rapture of repose that's there ; The fix'd yet tender traits, that streak The languor of the placid cheek ; And but for that sad, shrouded eye, That fires not,—wins not,—weeps not now ; And but for that chill, changeless brow, Where cold obstruction's apathy Appals the gazing mourner's heart, As if to him it could impart The doom he dreads, yet dwells upon : Yes, but for these and these alone, Some moments, ay, one treach'rous hour, He still might doubt the tyrant's power. So fair, so calm, so softly seal'd, The first, last look by death revealed. Byron's Giaour. An easy death—euthanasia—is what all desire; and fortunately, whatever may have been the previous pangs, the closing scenes, in most ailments, is generally of this character. In the beautiful mythology of the ancients, Death was the daughter of Night, and sister of Sleep. She was the only divinity to whom no sacrifice was made, because it was felt that no human interference could arrest her arm; yet her ap- proach was contemplated without any physical apprehension. The representation of Death as a skeleton covered merely with skin on the monument at Cumse was not the common allegorical picture of the period. It was generally depicted on tombs as a friendly genius, hold- ing a wreath in his hand, with an inverted torch,—a sleeping child, winged, with an inverted torch, resting on his wreath; or as Love, with a melancholy air, his legs crossed, leaning on an inverted torch,—itself a beautiful emblem of the gradual self-extinguishment of the vital flame.1 The disgusting representations of Death from the contents of the char- 1 D'Israeli, Curiosities of Literature, 2d Series, Amer. edit., vol. ii. p. 44, Boston, 1834. PHYSIOGNOMY OF DEATH. 741 nel house would not seem to have been common until the austerity of the 14th century, and are beginning to be abandoned. In more recent times, Death has been portrayed as a beautiful youth, and it is under this form that he is represented by Canova on the monument erected in St. Peter's at Rome, by George the Fourth of England, in honour of the Stuarts. t INDEX. i. refers to the first, and ii. to the second, volume. Aberration of refrangibility, ii. 57 sphericity, ii. 56 Abortion, ii. 509 Absence of mind, ii. 644 Absorption, i. 206 accidental, i. 267 of chyle, i. 206 cutaneous, i. 263 decomposing, i. 456 digestive, i. £06 of drinks, i. 230 of excrementitial secretions, i. 260 internal, i. 260 interstitial, i. 260, 456 of lymph, i. 238 organic, i. 260 of recrementitial secretions, i. 260 of solids, i. 260 venous, i. 253, 254 Abstinence, deaths from, i. 124 effects of, i. 124 Academia del Cimento, experiments of the, on the gizzards of birds, i. 92 Acarus Crossii, ii. 365 folliculorum, i. 506 Achromatopsia, ii. 126 Acid, acetic, where found, i. 54 benzoic, i. 54 where found, i. 54 carbonic, quantity of, consumed in re- spiration, i. 309 where met with, i. 44 lactic, where found, i. 54 muriatic, where found, i. 46 oxalic, where met with, i. 54 phosphoric, where met with, i. 45 uric, where met with, i. 52 xanthic, where met with, i. 52 Adipocire, how formed, ii. 221 Adipous exhalation, i. 485 Admiration, expression of, ii. 351 Adolescence, age of, ii. 616 Aeration, i. 304 Affections, what, ii. 147, 170 African race, ii. 680 After-birth, ii. 511 After-pains, ii. 512 Age, adult, ii. 616 critical, ii. 402, 619 Ages, the, ii. 601 Ages, of nature, ii. 463 Air, atmospheric, properties of, i. 281 drawn into the veins, i. 236 expulsion of, from the intestines, i. 193 in the intestines, nature of the, i. 185 in the stomach, nature of the, i. 174 Albino, state of the eyes of the, ii. 59 Album graecum, what, i. 188 Albumen, where met with, i. 48 concrete, where met with, i. 48 liquid, where met with, i. 48 Albuminose, where met with, i. 48 Aliments, classification of, i. 115 Allantoid vesicle, ii. 536, 562 Alphabet, how formed, ii. 330 Aluminium, where found, i. 46 Ambiguity, sexual, ii. 416 American race, ii. 683 Amnion, ii. 538, 549 Anastomoses of vessels; effects of, on the cir- culation, i. 436 Anatomie vivante, i. 63 Androgynous being, ii. 367 Anencephali, ii. 231 Angle, facial, ii. 177 occipital, ii. 180 visual, ii. 129 Anguillulae intestinales, i. 887 Anguish with bodily suffering, expression of, ii. 350 Angus, Mr., trial of, ii. 444 Anhelation, i. 304 Animal spirits, i. 670 Animalcules, spermatic, ii. 383 Animalculists, ii. 458 Animality, what, i. 39 Animals and vegetables, differences between, i. 39 cold-blooded, what, i. 587 warm-blooded, i. 587 Anomalies of conformation, ii. 592 Anorthoscope, ii. 141 Antagonism of nerves, ii. 243 Antipathies, ii. 654 Apparatus, what, i. 62 Appareil pigmental, i. 496, 677 Appetite, i. 121 Arcus senilis, ii. 64 Ardor venereus, ii. 411 Areola, ii. 518 tubercles of the, ii. 518 Areolar tissue, i. 58 744 INDEX. Areolar tissue, secretion of the, i. 485 Arsenic, where found, i. 47 Arterialization, i. 304 Arteries, i. 340 circulation in the, i. 410 locomotion of, i. 435 Articulation, ii. 327 Articulations, ii. 227 Asiatic race, ii. 682 Association, effects of, ii. 673 Athemprobe, i. 296 Atmospherization, i. 304 Atrabiliary capsules, i. 244 Attitude, ii. 283 erect, ii. 284 horizontal, ii. 289 on one foot, ii. 288 on both feet, ii. 283 on the knees, ii. 288 sitting, ii. 288 Audition, organs of, ii. 17 physiology of, ii. 32 Aura seminis, what, ii. 383, 428, 435 insufficient for effecting fecundation, ii. 435 Auscultation, ii. 29 Australian race, ii. 684 Automatic power of the blood, i. 419 Axis, cerebro-spinal, i. 627 Azote. (See Nitrogen.) Aztec children, ii. 688 B. Ballottement, ii. 503 Bartholin, glands of, ii. 392 Beaumont, Dr., case by, i. 170 Bearing a load, physiology of, ii. 299 Beastings, what, ii. 524 Belching, i. 197 Besoin de respirer, i. 285, ii. 603 Bewegungssinn, ii. 258 Bier-right, ii. 656 Biffin, Miss, her case, i. 694, ii. 158 Bildungstrieb, i. 457, ii. 455, 457 Bile, i. 543 colouring principle of the, i. 53 secretion of the, i. 537 use of, in digestion, i. 180 yellow colouring principle of the, i. 53 Biliary apparatus, i. 527 secretion, i. 527 Bilin, i. 56 Biliphaein, i. 53 Biliverdin, i. 53 Births, legitimate and illegitimate, ii. 479 male, more dangerous, ii. 484 and female, proportion of, ii. 481 Black man of Gmelin, ii. 680 Blastema, i. 465 Blastoderma, ii. 533 Blindness, caused by marriage of near relations, ii. 689 (note) Blood, i. 354 aeration of the, i. 304 agency of the, in health and disease, i. 150 analysis of the, i. 376 arterialization of the, i. 304 atmospherization of the, i. 304 buffy coat of the, i. 379 casein, i. 50, 363 clot of the, i. 368 Blood, coagulation of the, i. 373 coloration of the, i. 314 corpuscles, red, i. 359 corpuscles, white, i. 364 of different veins, i. 382 disks, i. 359 fibre of the, i. 370 of the foetus, analysis of the, ii. 585 forces that propel the, i. 425 forces that retard the, i. 434 globules of the, i. 359 halitus of the, i. 366 of inflammation, i. 378 inflammatory crust of the, i. 379 infusion of substances into the, i. 452 life of the, ii. 719 motive power in the, i. 419 quantity of, i. 355 red colouring principle of the, i. 53, 363 specific gravity of the, i. 358 transfusion of, i. 451 velocity of the, i. 436 venous, i. 357 inspiration of, i. 426 weight of in the body, i. 356 Blowing the nose, i. 300 Bodily suffering, expression of, ii. 350 Body, human, specific gravity of the, ii. 295 Bones, i. 57, ii. 222 analysis of, ii. 225 spongy, use of in olfaction, i. 723 Born alive, ii. 257 Bosjesman female, generative organs of the, ii. 388 nates of the, i. 494 Brace, Julia, deaf, dumb, and blind, ii. 160 Brain, i. 630 analysis of the, i. 654 circulation in the, i. 443, 660 convolutions of the, an index of the mind, ii. 183 decussation of the, ii. 240 fatty matter of the, i. 54 insensible, i. 660 movements of the, i. 662 of the negro, ii. 175 the organ of the mind, ii. 149 a plurality of organs, ii. 184 protections of the, i. 627 ratio of the weight of the, to the other parts, ii. 177 size of the, ii. 173 Breasts, ii. 515 Bridgman, Laura, case of, ii. 161 Brown man, ii. 682 Buffy coat of the blood, i. 379 Burns, Miss, case of, ii. 444 Byron, Admiral, effects of prolonged hunger on, i. 123 C. Caducity, ii. 620 Calcium, where found, i. 45 Callipsedia of C. Quillet, ii. 479 Caloric, laws of, i. 586, 690 Caloricite, of Chaussier, i. 603 Calorification, i. 585 circumstances influencing, i. 601 seat of, i. 601 theories of, i. 603 INDEX. 745 Capillary circulation, i. 416 vessels, i. 340 Carbon, where found, i. 44 Cartilages, i. 57, ii. 229 Casein, where met with, i. 49 Castes, table of, ii. 462 Catamenia, i. 501, ii. 402 Caucasian race, ii. 678 Cell agency in nutrition, i. 463 Cell, germinal, i. 463 life, i. 468 Cells, epidermic, i. 677 epithelial, i. 686 formation of, i. 463 primordial, i. 463 Cellular fibre, i. 58 membrane, exhalation of, i. 485 Cephalo-spinal fluid, i. 631, 663 CerebeUum, i. 635 the regulator of motion, ii. 234 Cerebrum, i. 630 Cerumen, i. 506 Chabert, M., his resistance to heat, i. 689 Cheselden's case of the boy restored to sight, ii. 136 Chick in ovo, developement of the, ii. 528 Childhood, age of, ii. 612 Chinese race, ii. 682 Chlorine, where found, i. 46 Cholepyrrhin, i. 53 Cholesterin, i. 56, 545 Chondrin, i. 51 Chorion, ii. 529, 548 Choroid, physiology of the, ii. 84 Chyle, i. 184 brute, i. 178 where formed, i. 184 Chylification, i. 177 Chyliferous apparatus, i. 207 Chylosis, i. 207 physiology of, i. 221 Chyme, i. 139 Chymifieation, i. 139 Cilia, uses of the, ii. 92 Ciliary motion, ii. 357 processes, uses of, ii. 88 Circulation, i. 330 in arteries, i. 410 in birds, i. 453 in the brain, i. 442, 660 capillary, i. 416 in fishes, i. 454 in the foetus, ii. 567, 588 in the heart, i. 390 in insects, i. 454 in mammalia, i. 453 in the portal system, i. 333, 445 physiology of the, i. 388 in reptiles, i. 453 in veins, i. 422 use of the, i. 449 velocity of the, i. 437 Circulatory apparatus, i. 332 . .co in animals, i. 458 Circumcision in the female, ii. 389 Clairvoyance, ii. 634 Climacteric years, ii. 624 Clot of the blood, i. 368 Ccenaesthesis, ii. 142 _ Coagulation of the blood, i.6t6 Coagulum of the blood, i. 3ba Cold, effects of severe, 1. 593 Colostrum, what, ii. 524 Colouring matter of organs, exhalation of the, i. 496 Colours, accidental, ii. 104 complementary, ii. 104 harmonic, ii. i04 insensibility to, ii. 127 opposite, ii. 104 Combustibility, preternatural, i. 370 Combustion, spontaneous, i. 370 Commodus, his feats, ii. 230 Composition of man, i. 43 Compounds of organization, i. 47 Conception, ii. 427, 474 at different ages, ii. 475 at different seasons, ii. 475 double, ii. 476 physiology of, ii. 427, 474 signs of, ii. 474 Concord, ii. 31 Condiments, i. 118 Conformation, anomalies of, ii. 592 Congenital affections, ii. 595 Conjunctiva, uses of the, ii. 96 Connate affections, ii. 595 Consonants, ii. 332 Constitution, ii. 663 Contractility, i. 41, ii. 254 Contractilite de tissu, i. 65 par defaut d'eztensio?i, i. 65 Copper, where found, i. 45 Copulation, ii. 423 Cord, jelly of the, ii. 560 umbilical, ii. 559 Corpus luteum, ii. 440 Corium phlogisticum, i. 379, ii. 718 Corpora Wolffiana, ii. 541 Corpuscles, blood, i. 359 granulated, of the blood, i. 364 lymph, i. 245 nerve, i. 607 Pacinian, i. 640 red, i. 359 of touch, i. 640 white, i. 364 Correlation of functions, ii. 645 Correlations, functional, ii. 646 mechanical, ii. 645 Cortical membrane, ii. 551 Cortex ovi, ii. 551 Coughing, i. 299 Cowper, Spencer, his case, ii. 297 Crania, measurements of, of different races, n. 176 .. Craniological system of Gall, u. 190 Spurzheim, ii. 193 Craniology, ii. 189 Cranioscopy, ii. 189 Cranology, ii. 189 Crassamentum of the blood, i. 368 Cretinism, ii. 669 Critical age, ii. 402, 619 Cruor of the blood, i. 368 Cruorin, i. 370 Crusta pleuritica, i. 379, ii. 718 Cry, ii. 326 Crying, i. 303 expression of, ii. 348 of animals, i. 303 Crypsorchides, ii. 373 Crypts, i. 58, 471 sebaceous, i. 505, 680 Curvatures of vessels, effects of the, on the cir- culation, i. 435 746 Cutaneous exhalation, i. 497 Cutaneous follicles or glands, i. 680 Cutis anserina, ii. 353 Cutting, Margaret, her case, ii. 324 Cytoblast, i. 463 Cytoblastema, i. 463 D. Dazzling, ii. 104 Deaf-dumb, intelligence of the, ii. 158 and blind, ii. 159 Deaf-dumbness, caused by marriage of near relations, ii. 689 (note) * Death, ii. 721 accidental, ii. 726 from old age, ii. 722 signs of, ii. 737 simulated, ii. 738 Decapitation, death by, i. 668 Decarbonization, i. 304 Decidua, ii. 487 refiexa, ii. 488, 551 Declamation, ii. 341 Decrepitude, ii. 622 Defecation, i. 190 Deglutition, i. 135 of air, i. 139 Demodex folliculorum, i. 506 Dentition, first, ii. 606 second, ii. 612 Depressing passions, ii. 347 Depuration, cutaneous, i. 519 urinary, i. 552 Derivation, i. 425 Desires, instinctive, ii. 145 Developement, foetal, ii. 547 Diastole of the heart, i. 393 Diet, variety of, necessary for man, i. 113 Differences, acquired, amongst mankind, ii. 665, 669 individual, ii. 659 natural, ii. 665 Digestion, i. 73 buccal, i. 130 in the large intestine, i. 185 in the small intestine, i. 176 oral, i. 130 of solids, physiology of, i. 121 of liquids, physiology of, i. 194 of the stomach, after death, i. 160 physiology of, i. 120 theories of, i. 147 theory of, by chemical solution, i. 148 by coction, i. 147 by fermentation, i. 148 by putrefaction, i. 148 by trituration, i. 148 Digestive organs, i. 73 of birds, i. 89 of ruminant animals, i. 88 Discord, ii. 31 Dislodging a stake, physiology of, ii. 299 Distance, appreciated by audition, ii. 46 appreciation of by vision, ii. 129 Diverticula, i. 441 Docimasia pulmonum, i. 296 Dragging a weight, physiology of, ii. 299 Dreams, ii. 630 waking, ii. 637 Drinking, i. 195 DEX. Drinks, i. 118 absorption of, i. 230 Duct, thoracic, i. 214 Duverney, glands of, ii. 392 E. Ear, anatomy of, ii. 17 external, physiology of the, ii. 32 internal, physiology of the, ii. .'19 middle, physiology of the, ii. 33 musical, ii. 42 trumpet, ii. 28 Echo, ii. 28 Egg, incubation of the, ii. 528 Elain, i. 54 Elasticity of tissue, i. 64 Elementary structure of animal substances, i. 59 Elements, inorganic, i. 35, 44 organic, i. 36, 47 containing azote, i. 47 not containing azote, i. 53 Emboltement des germes, ii. 459, 465 Embryo. (See Foetus.) Embryology, ii. 527 Emotions, ii. 147, 170 expressions of the, ii. 355 Encasing of germs, ii. 459, 465 Encephalon, i. 627 size of the, in the races, Ac, of man, ii. 176 Endosmose, i. 66 Engastrimism, ii. 320 Entozoon of the follicles, i. 506 Epigenesis, ii. 455 Epiglottis, use of the, in deglutition, i. 136 Epithelial cells, i. 685 Epithelium, ciliated, i. 687 cylinder, i. 686 pavement, i. 686 tessellated, i. 686 Erectile tissues, i. 443 Erection, ii. 423 Eructation, i. 197 Erythroid vesicle, ii. 562 Ethiopian race, ii. 680 Eustachian tube, uses of the, ii. 37 Evolution, doctrine of, ii. 458 Excitability, ii. 715 Excito-motory nerves, i. 649 Exhalants, i. 456, 471 Exhalations, i. 485 adipous, i. 489 areolar, i. 485 capsular, i. 497 colouring, i. 496 cutaneous, i. 497 dermic, i. 497 external, i. 497 gaseous, i. 501 internal, i. 485 menstrual, i. 501 mucous, i. 497 of mucous membrane, i. 497 of the marrow, i. 495 of the skin, i. 497 pigmental, i. 496 pulmonary, i. 497 serous, i. 486 synovial, i. 488 vascular, i. 486 Exhilaration, ii. 347 INDEX. 747 Exosmose, i. 66 Expansibility, vital property of, i. 419 Expectoration, i. 301 Expiration, i. 292 Expression, ii. 300 depressing, ii. 347 exhilarating, ii. 347 Extensibility of tissue, i. 64 Extract of meat, i. 51 Extractive of meat, i. 51 Eye, achromatism of the, ii. 83 accessory organs to the, ii. 73 accommodation of the, to distances, ii. 109 insensibility of the, to colours, ii. 126 Eyeball, muscles of the, uses of the, ii. 93 coats of the, uses of the, ii. 84 diaphanous parts of the, ii. 64 dimensions of the, ii. 73 muscles of the, uses of the, ii. 92 refracting power of the, ii. 80 transparent parts of the, ii. 64 Eyelids, uses of, ii. 9i Eyes, unequal foci of the, ii. 123 Face, muscles of the, ii. 342 Faculties, affective, ii. 147, 170 emotive, ii. 147, 170 of the heart, ii. 147 intellectual, ii. 166 and moral, physiology of the, ii. 166 mental, ii. 166 moral, ii. 147, 170 • of the heart, ii. 147, 170 Fffices, properties of the, i. 188 Fakeers of India, ii. 738 Falsetto voice, ii. 338 Fat, exhalation of the, i. 485 Fatigue, sense of, ii. 145 Fatty matter of the brain and nerves, i. 654 Fear, expression of, ii. 350 Fecundation, ii. 427 Feeling, common sense of, ii. 143 bodily, ii. 143 of life, ii. 143 Female, characteristics of the, ii. 666 Females, born, ratio of, ii. 480 Fibre, what, i. 59, 62 albugineous, i. 60 areolar, i. 59 elementary, i. 59 laminated, i. 59 medullary, i. 59 muscular, i. 59 nervous, i. 59, 656 of the blood, i. 370 pulpy, i. 59 Fibres, primary, i. 59 Fibrils, formative, of Darwin, ii. 457 Fibrin, where met with, i. 48 Filament, what, i. 59, 62 seminal, ii. 383 spermatic, ii. 383 Flexibility of tissues, i. 64 Flexors, preponderance of the, n. 2iHi Fluid, nervous, i. 671 Fluids, division of, i. 63 of the human body, l. 62 Fluorine, where found, i. 46 Flying, ii. 298 Foetal existence, ii. 527 Foetus, of the, ii. 527 anatomy of the, ii. 527 animal functions of the, ii. 598 blood of the, ii. 585 calorification of the, ii. 598 circulation of the, ii. 503, 567, 588 dependencies of the, ii. 547 developement of the, ii. 527, 547 digestion of the, ii. 568, 586 dimensions of the, ii. 542 effect of maternal imagination on the, ii. 470, 594 expression of the, ii. 600 * external senses of the, ii. 598 genital organs of the, ii. 569 hepatic secretion of the, ii. 568 histology of the, ii. 527 increment of the, ii. 527 in foetu, ii. 459 intellectual and moral faculties of the, ii. 599. internal senses of the, ii. 599 motion of the, ii. 599 nutrition of the, ii. 573 nutritive functions of the, ii. 573 peculiarities of the, ii. 563 physiology of the, ii. 572 position of the, ii. 545 reproductive functions of the, ii. 600 respiration of the, ii. 566, 586 secretions of the, ii. 597 urinary secretions of the, ii. 569 weight of the, ii. 542 Follicle, i. 58, 471 sebaceous, or cutaneous, i. 680 Follicular secretions, i. 502 Food of man, i. 106 prehension of, i. 127 Force, cosmic, i. 457, ii. 455 essential, i. 457, ii. 455 germ, i. 457 of formation, i. 457, ii. 455 tutritive, i. 457 plastic, i. 457, ii. 455 of vegetation, i. 457 vital, ii. 696 Forces, motive, seat of the, ii. 233 Foreshortening, ii. 130 Free-martin, ii. 420 Friction of the blood, i. 434 Functions, animal, i. 626 classification of the, i. 71 correlation of, ii. 645 nutritive, i. 73 of man, i. 69 of relation, i. 626 reproductive, ii. 360 table of the, i. 71 G. Galactophorous tubes, ii. 516 Gall's craniological system, ii. 190 Galvanism, effects of, on the muscles, ii. 255 Ganglia, sensory, i. 669 Ganglionic nerve, i. 644 Ganglions, glandiform, i. 58, 575 nervous, i. 58 Gaping, i. 301 Gas animale sanguinis, i. 367 Gases, permeability of tissues by, i. 68 748 INDEX. Gases in the stomach, i. 174 in the small intestines, i. 185 in the large intestines, i. 190 Gaseous exhalation, i. 501 Gastric juice, i. 145 Gelatin, where met with, i. 51 nutrient properties of, i. Ill Gemeingefuhl, ii. 142 Gemeinsinn, ii. 142 Generation, ii. 360, 422 ab animalculo maris, ii. 466. alternate, ii. 369 animalcular theory of, ii. 466 by spontaneous division, ii. 367 equivocal, ii. 360 * fissiparous, ii. 367 gemmiparous, ii. 367 marsupial, ii. 368 oviparous, ii. 368 ovo-viviparous, ii. 368 physiology of, ii. 422 regular, ii. 360 spontaneous, ii. 360 theories of, ii. 454 univocal, ii. 360 viviparous, ii. 368 Generative apparatus, ii. 370 Genesique, la, ii. 145 Genital organs of the female, ii. 387 foetus, ii. 569 male, ii. 370 Germ-force, i. 457 Germ spot, ii. 528. Germinal cell, i. 463 membrane, ii. 533 spot, i. 463, ii. 401, 528 Germs, dissemination of, ii. 465 encasing of, ii. 459, 465 vital, Darwin's notion of, ii. 457 Gestation, ii. 487 of animals, ii. 477 Gestures, ii. 341 Girandelli, Madame, her resistance to heat, i. 688 * Gland, described, i. 58, 472 Glandiform ganglions, i. 575 Glands of Brunner, i. 96 ductless, i. 575 of Lieberkiihn, i. 96 of Peyer, i. 97 Glandulas odoriferas, i. 506 Glandular secretions, i. 507 Globular elements of tissues, i. 460 Globules, blood, i. 359 fibrinous, of the blood, i. 364 Globulin of the blood, i. 363, 370 Globulins, i. 364 Gluten of the blood, i. 370 Glycerin, i. 54 Goitre, i. 244, ii. 669 Granula seminis, ii. 384 Gras des cimetieres, ii. 221 Gravity retards the blood, i. 435 Greisenbogen, ii. 64 Growth of the body, i. 468 Guillotine, death by the, i. 668 Gustation, i. 698 H. Habit, ii. 669 Haemacyanin, i. 53 Hsemadynamometer, i. 409 Hsemaphaoin, i. 53 Haematin, i. 53, 363 Haematoglobulin, i. 363 Haematosis, i. 304 Haemodrometer, i. 438 Hair, i. 680 Halitus of the blood, i. 366 sperm, ii. 428 Hallucinations, ii. 637 Hand, advantages of the, as an organ of touch, i. 693 Harmony, what, ii. 31 Hawking, i. 301 Hearing, ii. 17 immediate functions of, ii. 42 improved by cultivation, ii. 48 nerve of, ii. 41 organ of, ii. 17 Heart, i. 332 a double organ, i. 331 beat of the, i. 400 circulation through the, i. 390 foetal, pulsation of the, ii. 503 force of the, i. 409 impulse of the, i. 400 lymph, i. 251 sounds of the, i. 393 suction power of the, i. 425 weight, &c, of the, i. 337 Heart's action, cause of the, i. 402 Heat, animal, i. 585 of different animals, i. 588 sense of, i. 692 venereai, ii, 411, 423 Hellsehen, ii. 634 Hemachroin, i. 370 Hematin, i. 53, 370 Hematocrystallin, i. 366 Hematoidin, i. 366 Hematosin, i. 53, 370 Hemicephali, ii. 231 Hepar sanguinis, i. 368 Hermaphrodism, ii. 416 Hermaphrodite, ii. 367, 416 Hexathyridium venarum, i. 387 Hibernation in man, ii. 738 Homo diluvii testis, ii. 463 Honeywell, Miss, her case described, i. 695 Hottentot Venus, i. 494 Humorists, i. 57 Hunger, i. 121 Hunter, Mr., singular case of, ii. 737 Hybridity, ii. 472 Hybrids, doctrine of, ii. 461 Hydrogen, where found, i. 44 Hygrometric property, i. 65 Hymen, use of, ii. 390 Hypnotism, ii. 633 I. Idiosyncrasy, ii. 663 Illegitimate births, ratio of, ii. 479 Illusions, mental, ii. 637 optical, ii. 129, 139 spectral, ii. 637 Imagination, effect of, ii. 653 maternal, influence of the, on the fcetus, ii. 470 Imbibition, i. 65 Imitation, effects of, ii. 674 INDEX. 749 Inanition, i. 125 Incitability, ii. 715 Incubation of the egg, ii. 528 hulividiialit'dtssinn, ii. 142 Infancy, ii. 601 first period of, ii. 601 second period of, ii. 606 third period of, ii. 612 Inflammatory crust, i. 379 Infusion of medicines into the blood, i. 451 Innervation, i. 670 Inorganic bodies, i. 34 Insalivation, i. 131 Inspiration, i. 286 of venous blood, i. 426 first, ii. 603 Instinct, ii. 163, 702 Instincts, ii. 163 Instinctive desires, ii. 145 signs, ii. 355 Insula sanguinis, i. 368 Intellect, ii. 166 Intellectual sphere, sources of, ii. 157 Intercellular substance, i. 465 Intercostal nerve, great, i. 644 Intermediate system of vessels, i. 343 Iris, uses of, ii. 85 Iron, where found, i. 45 Irritability, i. 42, ii. 254 restored by injecting arterial blood, ii. 715 Irritation, constitutional, ii. 647 Itching, ii. 143 Jelly of the cord, ii. 560 Joints, ii. 227 Joy, expression of, ii. 351 K. Kalmuck race, ii. 682 Kidney, i. 552 royal road to the, i. 572 secretion of the, i. 552 Kiestein, ii. 501 Kissing, ii. 347 Korpergefuhl, ii. 142 Kreatin, i. 51 Kreatinin, i. 51 Kyestein, ii. 501 L. Labour, ii. 509 duration of, ii. 513 premature, ii. 509 Lachrymal apparatus, ii. 74 secretion, i. 520 Lactation, ii. 515 Lacteal secretion, i. 575, u. 515 Lacteals, i. 207 Lactiferous tubes, ii. 516 Laminated tissue, i. 58 Language, ii. 300 artificial, n. 327 _ articulate, ii. 327 Language, natural, ii. 326 origin of, ii. 328 Laughing, i. 302, ii. 326 Laughter, i. 302, ii. 326, 347, 355 broad, ii. 348 of animals, i. 303 Lead, where found, i. 45 Leaping, ii. 293 Lebensgefuhl, ii. 142 Lebenssinn, ii. 142 Lebensturgor, i. 419 Legitimate births, ratio of, ii. 479 Legumin, i. 50 Lenses, various, ii. 54 Letters, how divided, ii. 330 Life, ii. 696 natural period of, ii. 721 cell, i. 468 of the blood, ii. 719 Ligaments, i. 57, ii. 229 Light, ii. 49 colour and decomposition of, ii. 55 diffraction of, ii. 124 duration of the impression of, on the retina, ii. 140 intensity of, ii. 51 reflection of, ii. 51 refraction of, ii. 52 velocity of, ii. 50 Likeness of child to parent, remarks on the, ii. 470 Line, facial, ii. 177 occipital, ii. 180 Liquids, prehension of, i. 195 Liquor amnii, ii. 549 false, ii. 549 sanguinis, i. 379 seminis, ii. 384 Listening, ii. 48 Liver, histology of the, i. 529 secretion of the, i. 527 Lochia, ii. 512 Locomotion, nervous system of, ii. 234 Locomotility, ii. 208 Locomotive influx, ii. 234 Longsightedness, ii. 116 Lung-proof of infanticide, i. 296 Lungenprobe, i. 296 Lymph, i. 245 coagulable, i. 370 corpuscles, i. 245 heart, i. 251 Lymphatic apparatus, i. 238 Lymphosis, i. 238, 248 M. Macula germinativa, ii. 401 Magnesium, where found, i. 46 Magnetism, animal, ii. 633 Malay race, ii. 684 Males born, ratio of, ii. 480 Mammae, ii. 515 secretion of the, i. 575 Manganese, where found, i. 45 Manhood, age of, ii. 619 Mankind, varieties of, ii. 675 Mantle, i. 679 Mariotte, experiment of, ii. 97 Marks, mother's, ii. 593 Marriage of near relations, results of the, ii. 689 (note) 750 INDEX. Marrow, i. 495, ii. 226 Mastication, i. 131 Mastoid cells, uses of the, ii. 35 Matiere extractive du bouillon, i. 51 Matrix, i. 463 Meatus auditorius externus, uses of the, ii. Mechanical principles, ii. 266 Meconium, ii. 568, 597 Medulla oblongata, i. 636 ossium, i. 495 spinalis, i. 638 Megalanthropogenesis, ii. 479 Melancholy, expression of, i. 352 Melody, ii. 31 Membrana granulosa, ii. 399, 531 tympani, uses of the, ii. 33 Membrane, i. 58 compound, i. 58 fibrous, i. 58 germinal, i. 465 mucous, i. 58, 685 nictitating, ii. 73 serous, i. 58 simple, i. 58 Menses, ii. 402 Menstrual exhalation, i. 501 Menstruation, ii. 402 vicarious, ii. 406 Mental faculties, ii. 147 Mesenteric glands, i. 212 Mesmeric sleep, ii. 633 Mesmerism, ii. 633 Metagenesis, ii. 369 Milk, ii. 515, 522 Mind, not proportionate to the state of the senses, ii. 157 seat of the, ii. 207 Miscarriage, ii. 509 Mitchell, the boy, case of, i. 729 Moi, seat of the, ii. 207 Molecules, organic, of Buffon, ii. 456 Mongolian race, ii. 682 Monorchides of the Cape of Good Hope, ii. 374 Monsters, ii. 592 double, ii. 595 Monstrosities, ii. 592 Moral acts, ii. 166 Mother's marks, ii. 593 Motility, ii. 713 Motion, ciliary, ii. 357 encephalic seat of, ii. 241 involuntary, ii. 233 muscular, ii. 208 nerves of, ii. 243 physiology of, ii. 229 sensation of, ii. 258 vibratory, ii. 357 voluntary, ii. 208, 229 Motive apparatus, ii. 209 forces, seat of the, ii. 229 Mouvement de ballottement, ii. 503 Movements, ii. 289 locomotive, ii. 289, 291 partial, ii. 289 Mucous follicular secretion, i. 502 exhalation, i. 497 membranes, i. 685 Mucus, i. 52, 502 where met with, i. 52 Mulatto less fertile, ii. 473 Muscas volitantes, ii. 100 Muscles, i. 57, ii. 209 analysis of, ii. 220 Muscles of animal life, ii. 210 colour of, ii. 218 contraction of, ii. 244 of organic life, ii. 210 non-striated, ii. 210 relaxation of, ii. 246 simple and compound, ii. 219 striated, ii. 210 , state of, in action, ii. 245 table of, ii. 280 Muscular contraction, duration of, ii. 262 extent of, ii. 266 force of, ii. 259 theories of, ii. 249 varieties of, ii. 299 velocity of, ii. 263 fibre, i. 59, ii. 210 motion, ii. 208 nervous centre of, ii. 233 phenomena of, ii. 247 physiology of, ii. 229 sense, ii. 142 system of animal life, ii. 229 web, i. 679 Musical tone, ii. 31 Musielsinn, ii. 258 Muteosis, ii. 341 Myopy, ii. 115 N. Naevi materni, ii. 593 Nails, i. 684 Natural bodies, i. 33 signs, ii. 355 state of man, i. 109 Nature, ages of, ii. 463 Nausea, i. 198 Navel-string, ii. 559 Negro-race, ii. 680 Nerve corpuscle, i. 607 fibre, i. 606 Nerves, i. 58, 638 composition of the, i. 654 excito-motory, i. 649 fatty matter of, i. 54 incitors of motion, ii. 254 M. Hall's division of, i. 649 pneumogastric, effects of the section of the, on digestion, i. 162 on respiration, i. 327 reflex system of, i. 649 sensible and insensible, i. 664 spinal, i. 649 Sir C. Bell's division, i. 643 Nervi-motion, Dutrochet's views of, i. 462 Nervous fibre, i. 606 fluid, i. 671 system, i. 626 Neurine, i. 654 tubular, i. 655 vesicular, i. 655 New Zealander, head of, i. 470 Nightmare, ii. 631 Nipples, ii. 517 Nisus formativus, i. 457, ii. 455, 457 Nitrogen, quantity of, consumed in respira- tion, i. 307 where found, i. 45 sources of, in the food, i. Ill Norma verticalis of Blumenbach, ii. 181 INDEX. 751 Nose, blowing the, i. 300 use of the, in smell, i. 723 Nuclei, i. 463 Nucleoli, i. 463 Nutrition, i. 45 agents of, ii. 459 force of, i. 457 Nutritive principle, peculiar, does not exist, i. 110 Nyctalopes, ii. 59 0. Odours, i. 716 classification of, i. 720 disengagement of, i. 717 divisibility of, i. 718 medical properties of, i. 721 nutritive properties of, i. 721 vehicles of, i. 719 Oil of bones, i. 495 Oken's bodies, ii. 541 Old age, ii. 620 Olein, where met with, i. 53, 54 Olfaction, i. 712 physiology of, i. 722 Onomatopoeia, ii. 329 Ophthalmoscope, ii. 63 Optic nerves, decussation of the, ii. 70 Organ, i. 62 Organic nerve, i. 644 Organization, i. 37 compounds of, i. 47 Organized bodies, characters of, i. 34 Organology, ii. 189 Oscitation, i. 301 Osculation, ii. 347 Osmazome, where found, i. 51 Ovarists, doctrine of the, ii 458 Ovary, secretion of the, i. 507 during menstruation, ii. 408 Ovists, ii. 458 Ovulation, ii. 408 Ovum, ii. 399 developement of the, ii. 539 ripe, ii. 408 Oxygen, where found, i. 44 quantity of, consumed in respiration, i. 306 Oxyprotein, i. 381 P. Pacinian corpuscles, i. 640 Pain, ii. 146 bodily, expression of, ii. 350 Pains, after, ii. 512 Painting, a variety of expression, ii. 357 Palpation, i. 676, 687 Palsy, theory of, ii. 249 Pancreatic juice, i. 524 secretion of the, l. 524 use of, in digestion, i. 180 Pandiculation, i. 302 _ Panniculus carnosus, i. 679 Panspermia, ii. 465 Panting, i. 304 Parturition, ii. 509 _ .. more dangerous in male births, n. 484 Parturition, mortality in, ii. 515 number of children dying during, ii. 484 Passions, ii. 170 expression of the, ii. 355 seat of the, ii. 155 Pavilion of the ear, uses of the, ii. 32 Pectoriloquy, ii. 320 Pepsin, i. 50, 156 Peptone, where met with, i. 48 Peripheral system of vessels, i. 343 Peristaltic action, i. 144 Peristole, i. 144 Perceptivity of plants, i. 41 Perspective, ii. 131 aerial, ii. 131 Perspiration, i. 507 Peyer's glands, i. 97 Phantasmascope, ii. 141 Phenakistiscope, ii. 141 Phonation, ii. 301 Phosphorus, where found, i. 45 Phrenologist, cerebral organs of the, ii. 180 Phrenology, ii. 184, 189 Phreno-magnetism, ii. 634 Phreno-mesmerism, ii. 634 Physical properties of the tissues, i. 64 Physiognomy, ii. 352 medical, ii. 353 Physiology, general, of man, i. 43 Picromel, where found, i. 56 Pigment exhalation, i. 496 Pigmentum nigrum, uses of the, ii. 84 Placenta, ii. 551 of the blood, i. 368 Placental souffle, ii. 503 Plasma, i. 379 Pneumogastric nerves, effect of the section of, on digestion, i. 162 on respiration, i. 327 Point, visual, ii. 115 Polystoma venarum, i. 387 Portal system, i. 353 of the kidney, i. 556 Potassium, where found, i. 46 Power, sensorial, ii. 208 Pregnancy, ii. 487 duration of, ii. 505 protracted, ii. 507 signs of, ii. 498 tubal, ii. 430 Prehension, ii. 300 of food, i. 127 of liquids, i. 195 Presbyopy, ii. 116 Presentations, various, ii. 513 Principle, nutritive peculiar, does not exist, i. 110 vital, ii. 696 Principles, mechanical, ii. 266 proximate of animals, i. 47 Proligerous disc, ii. 399 Propelling a body, how effected, ii. 299 Property, hygrometric, of tissues, i. 65 physical, of tissues, i. 64 vital, ii. 711 Prosopose, ii. 347 Protein, i. 47 Protogala, ii. 524 Pseiido-zoo-sjM'rrnes, ii. 430 Psychology, ii. 147 Puberty, ii. 616 Pulmonary transpiration, i. 498 752 INDEX. Pulse, doctrine of the, i. 444 venous, i. 391 Purgations, ii. 406 Pylorus, use of the, i. 14P Q. Quickening, ii. 502 R. S. Saliva, i. 521 use of, in digestion, i. 131 Salivary glands, i. 77, 521 secretion, i. 521 Sapidity, cause of, i. 701 Sanguification, i. 304 Savours, i. 701 classification of, i. 702 Schurze, of the Bosjesman female, ii. 389 Sculpture, a variety of expression, ii. 357 Sea-sickness, i. 199 Sebaceous follicles, i. 680 Secretion, i. 471, 475 follicular, i. 502 glandular, i. 507 simple, i. 485 vicarious, i. 483 Secretions, table of the, i. 484 Secretory apparatus, i. 471 Secundines, ii. 511 Selbstgefuhl, ii. 142 Self-feeling, ii. 142 Semen, secretion of, ii. 380 properties of, ii. 382 Seminal animalcules, ii. 383 filaments, ii. 383 granules, ii. 384 Seminists, ii. 458 Sens genital, ii. 145 Sensation, common, ii. 143 Sensations, i. 665 external, i. 673 internal, ii. 144 morbid, ii. 146 objective, i. 666 organic, ii, 144 subjective, i. 666 Sense of cold, ii. 142 geometrical, i. 695 hearing, ii. 17 heat, i. 692, ii. 142 hunger, ii. 142 individuality, ii. 143 life, ii. 143 locality, ii. 143 motion, ii. 142, 258 muscular, ii. 142, 258 smell, i. 712 taste, i. 698 thirst, i. 194, ii. 142 touch, i. 676 vision, ii. 48 pneumatic, ii. 142 sixth, of Buffon, ii. 142 regulating, i. 695 Senses, additional, ii. 142 Sensibility, i. 626, ii. 712 general, i. 664 less in the lower animals, ii. 152 physiology of, i. 665 special, i. 664 vital property of, ii. 702 Sensorial power, ii. 208 Sensory ganglia, i. 669 Serosity of the blood, i. 369 Serous exhalation, i. 486 of the areolar membrane, i. 485 Serum of the blood, i. 368 Sex, doubtful, ii. 416 of the foetus, ii. 570 Sexes, proportion of the, born, ii. 480 art of producing the, ii. 478 Sexual ambiguity, ii. 416 Sheep, fat-buttocked, i. 494 Short-sightedness, ii. 115 Show, the, ii. 510 Sighing, i. 301, ii. 326, 355 sound of, ii. 325 Sight, sense of, ii. 48 . Silicon, where found, i. 46 Singing voice, ii. 338 Sinuses, nasal, use of, in smell, i. 725 Sitting posture, ii. 288 Skeleton, living, exhibited, i. 63 Skin, i. 676 follicular secretion of the, i. 504 transpiratory secretion of the, i. 507 Skull, i. 628 Sleep, ii. 624 complete, ii. 629 I incomplete, ii. 629 mesmeric, ii. 633 necessity of, ii. 145 Races of man, ii. 675 division of the, ii. 677 origin of the, ii. 685 Racornissement, i. 65 Rage, expression of, ii. 350 Red man, ii. 684 Reflex system of nerves, i. 649 Regurgitation, i. 197 Reinigung, ii. 406 Rennet, i. 157 Repose, necessity of, ii. 145 Reproduction, desire of, ii. 422 functions of, ii. 360 instinct of, ii. 422 Respiration, i. 268, 285, 304 chemical phenomena of, i. 305 physiology of, i. 285 proof, i. 296 cutaneous, i. 326 effects of, on the circulation, i. 426 effects of section of nerves on, i. 327 of animals, i 329 first, i. 285, ii. 603 mechanical phenomena of, i. 285 Respirations, number of, i. 297 Respiratory organs, i. 268 Retina, uses of, ii. 89 Revery, ii. 644 Rigor mortis, ii. 735 Rubrin, i. 370 Rumination, i. 197 Running, ii. 295 Rut of animals, ii. 410, 423 INDEX. 753 Sleep walking, iir 632 Slumber, ii. 626 Smegma praeputii, i. 506 Smell, i. 712 acuteness of, in animals, i. 727 in the blind, i. 729 immediate function of the, i. 726 improved by education, i. 729 mediate functions of, i. 726 nerves of, i. 725 organs of, i. 712 Sneezing, i. 299 Sobbing, i. 303, ii. 355 Podium, where found, i. 46 Solander, Dr., effects of severe cold on, i. 593 Solidists, i. 57 Solids, i. 57 compound, i. 60 Somnambulism, ii. 632 Soul, seat of the, ii. 207 Sound, ii. 26 acute, malappreciation of, ii. 46 intensity of, ii. 29 reciprocating, ii. 27 reflection of, ii. 28 sympathetic, ii. 29 timbre of, ii. 31, 47 tone of, ii. 31 vehicle of, ii. 26 velocity of, ii. 27 Spaying, method of effecting, ii. 431 Spectra, ocular, ii. 105 Speech, ii. 327 Sperm, ii. 380, 382 Spermatic filaments, ii. 383 secretion, ii. 370, 380 Spermatists, ii. 458 Spermatozoa, ii. 383 Spermatozoids, ii. 383 in hydrocele, ii. 387 Spinal marrow, protection of the, i. 630 structure of the, i. 638 system of nerves, i. 649 Spirits, animal, i. 670 Spirometer, i. 293 Spitting, i. 300 Splanchnic nerve, i. 644 Spleen, i. 576 Spontaneity of plants, i. 41 Spurzheim's craniological system, ii. 193 Squeezing, ii. 299 Squinting, ii. 122 Standing, ii. 283 Stearin, where met with, i. 53 Steatozoon folliculorum, i. 506 Stereoscope, ii. 119 Stethoscope, ii. 29 Stillborn, ii. 483 ratio of males to females, ii. 484 Stomach, digestion of the, after death, i. 160 and kidney, connexion between the, i. 572 Stout, Mrs., her case, ii. 297 Strabismus, ii. 122 Straining, i. 192, 299 Stretching, i. 302 Structure, elementary, of animal substances, i. 460 Study, brown, ii. 644 Succus intestinalis, i. 178 Sucking, i. 195 Suckling, ii. 525 Suction power of the heart, i. 425 VOL. II.—48 Sudoriparous apparatus, i. 509 Suffering, bodily, expression of, ii. 350 Sugar, hepatic, i. 55 of diabetes, i. 55, 552 milk, i. 55 Sulphur, where found, i. 45 Superfecundation, ii. 485 Superfcetation, ii. 485 Supra-renal capsules, i. 243, ii. 566 Suspicion, expression of, ii. 352 Sutures, i. 628 Sweat, what, i. 520 Swimming, ii. 295 Sympathetic, great, i. 644 Sympathy, ii. 650 agents of, ii. 657 cerebral, ii. 657 direct, ii. 657 morbid, ii. 647 of contiguity, ii. 651 of continuity, ii. 651 remote, ii. 653 superstitions connected with, ii. 655 Synergies, ii. 646 Synovia, i. 488, ii. 229 System, i. 62 nervous, i. 626 nervous, of locomotion, ii. 234 Systole of the heart, i. 393 T. Tablier of the Bosjesman female, ii. 389 Tact, i. 676, 687 Tapetum, ii. 84 Tartar of the teeth, i. 524 Taste, i. 689 diversity of, in animals, i. 711 immediate functions of, i. 709 improvement of, by education,, i. 711 mediate functions of, i. 709' nerve of, i. 707 organs of, i. 699 physiology of, i. 704 Tattooing, i. 470 Tawny man, ii. 684 Tears, i. 520 secretion of the, i. 520 use of the, ii. 94 Teeth, i. 74, ii. 610 shedding of the, ii. 612' Temperament, ii. 154, 659 athletic, ii. 660 atrabilious, ii. 661 bilious, ii. 661 choleric, ii. 661 influence of, on the mind, ii 154 lymphatic,.ii. 661 melancholic, ii. 661 muscular, ii. 660 nervous, ii. 662 phlegmatic, ii. 661 pituitous, ii. 661 sanguine, ii. 660 Temperature, animal, i. 585 according to age, sex,&c.,.i. 599 depressed, effects of, i. 591 elevated, effects of, i. 596 of animals, table of, i..588 of bodies, i. 586' Terror, expression of, ii. 351 754 INDEX. Testes, descent of the, ii. 372, 571 secretion of the, i. 575, ii. 380 Testicondi, ii. 373 Textures, arrangement of, i. 60 Thaumatrope, ii. 141 Thigh-bone, neck of, advantage of the, i. 440 Thirst, i. 194 sense of, 194 Thoracic duct, i. 214 Thymus gland, i. 243, ii. 564 Thyroid gland, i. 243, ii. 566 Tickling, ii. 143 Tingling, ii. 144 Tissue, i. 59, 62 areolar, i. 59 albugineous, i. 59 compound, i. 60 fibrous, i. 486 laminated, i. 59 medullary, i. 60 muscular, i. 59 nervous, i. 60 primary, i. 59 pulpy, i. 60 Tissues, arrangements of, i. 60 permeability of, to gases, i. 68 physical properties of, i. 64 Titanium, where found, i. 47 Titillation, ii. 144 Toltecan race, ii. 683 Tone, i. 65 Tongue, i. 699 Tonicity, i. 65 Torpidity in man, ii. 738 Touch, i. 676, 687 acuteness of, i. 696 appreciation of temperature by, i. 689 corpuscles, i. 640 immediate functions of, 695 improved by education, i. 696 organs of, i. 676 regarded the first of the senses, i. 694 Townshend, Col., his case, i. 403 Transfusion, i. 451 Transpiration, cutaneous, i. 507 pulmonary, i. 498 Transposition of the viscera, ii. 592 Transudation, i. 66 Travail, ii. 509 Trichomonas vaginalis, ii. 392 Triplets, proportion of cases of, ii. 476 Trisplanchnic nerve, i. 644 Tubercles of the areola, ii. 518 'Turgor vitalis, i. 419 Tutamina cerebri, i. 627 oculi, ii. 74 Twins, proportion of cases of, ii. 476 U. "Umbilical cord, ii. 559 vesicle, ii. 536, 560 TJnderstanding, ii. 166 Urea, where met with, i. 52 Urinary organs, i. 552 secretion, i. 552 Urine, i. 560 secretion of, i. 552 Utero-gestation, ii. 487 Uvula, use of the, i. 134 V. Varieties of mankind, ii. 675 Vasa vasorum, i. 353 Vascular glands, i. 575 Vaterian corpuscles, i. 640 Vegetables and animals, differences between, i. 39 Vegetative nerve, i. 644 Veins, i. 349 circulation in the, i. 422 Vena porta, i. 353 Venous system, i. 349 blood, i. 357 Ventrale cutaneum of the Bosjesman female, ii. 389 Ventriloquism, ii. 320 Venus, Hottentot, i. 494 Vernix caseosa, i. 56, ii. 542 Vesicle, allantoid, ii. 536, 562 blastodermic, ii. 533 ' erythroid, ii. 562 intestinal, ii. 560 germinal, ii. 401, 528 of Purkinje, ii. 401, 528 umbilical, ii. 536, 560 Vessels, i. 57 Viability of child, ii. 508 Vibrations, sympathetic, ii. 29 Vibratory motion, ii. 357 Virility, age of, ii. 619 Vis insita, of Haller, i. 712 mortua, i. 69 medieatrix naturae, ii. 703 Viscus, i. 58 Visible direction, centre of, ii. 102 Vision, ii. 48 advantages of, to the mind, ii. 126 auxiliary functions, ii. 128 binocular, ii. 120 direct, ii. 106 direction of bodies appreciated by, ii. 129 distance appreciated by, ii. 129 distinct, point of, ii. 106 requisites for, ii. 107 double, ii. 120 erect, ii. 101 immediate function of, ii. 126 improved by education, ii. 142 indirect, ii. 106 magnitude, appreciated by, ii. 129 mediate functions of, ii. 128 motion, appreciated by, ii. 134 multiple, with one eye, ii. 123 nerves of, ii. 70 nocturnal, ii. 59 oblique, ii. 106 organ of, ii. 58 phenomena of, ii. 97 physiology of, ii. 78 position, appreciated by, ii. 129 seat of, ii. 99 single, ii. 117 surface of bodies appreciated by, ii. 129 Visual angle, ii. 129 point, ii. 115 Vital capacity, i. 293 force, ii. 696 particles, of Buffon, ii. 457 principle, ii. 696 properties, ii. 697 Vitality, ii. 696 INDEX. (00 Vitality of the blood, ii. 716 Vitelline, ii. 398, 562 disc, ii. 399 fluid, ii. 562 pedicle, ii. 561 pouch, ii. 561 Vitellus, ii. 398, 529 Vitia primae conformationis, ii. 592 Vocal apparatus, ii. 301 Voice, ii. 301 intensity of, ii. 310 native, ii. 326 nerves of, ii. 306 physiology of the, ii. 307 quality of the, ii. 319 timbre of the, ii. 319 tone of the, ii. 311 Volition, seat of, ii. 231 Vomiting, i. 198 at pleasure, i. 197 Vowels, ii. 331 W. Wagner's corpuscles, i. 640 Walking, ii. 291 Wants, ii. 145 Weeping, i. 303 expression of, ii. 347, 348 of animals, i. 303 Wheatstone, Professor, experiments by, ii. 119 Whispering, ii. 325 Whistelo's case, ii. 470 Whistling, ii. 325 Wolff's bodies, ii. 541 Writing, art of, ii. 330 Y Yawninar. i. 301, ii. 326, 355 Yolk. ii'.'39S. 529 Yolk bag, ii. 401 Zona pellucida, ii. 399 Zoohematin, i. 363 Zoospmnr.s, ii. 383, 469 THE END. BLANCHARD & LEA'S MEDICAL AND SURGICAL PUBLICATIONS. TO THE MEDICAL PROFESSION. In the present catalogue we have affixed prices to our publications, in obedience to the repeated requests of numerous members of the profession. While books, like all other articles, must necessarily vary somewhat in cost throughout the ex- tended territories of this country, yet our publications will generally be furnished at these rates by booksellers throughout the Union, who can readily and speedily procure any which they may not have on hand. To accommodate those physicians who have not convenient access to bookstores, or who cannot order through merchants visiting the larger cities, we will forward our works by mail,/ree of postage, on receipt of the printed prices in current funds or postage stamps. As our business is wholesale, and we open accounts with book- sellers only, the amount must in every case, without exception, accompany the order, and we can assume no risks of the mail, either on the money or the books* and as we only sell our own publications, we can supply no others. Physicians will, therefore, see the convenience and advantage of making their purchases, when- ever practicable, from the nearest bookseller. We can only add that no exertions are spared to merit a continuance of the gratifying confidence hitherto manifested by the profession in all works bearing our imprint. BLANCHARD & LEA. Philadelphia, August, 1857. *** We have now ready a new Illustrated Catalogue of our Medical and Scientific Publications, forming an octavo pamphlet of 80 large pages, containing specimens of illustrations, notices of the medical press, &c. &c. It has been pre- pared without regard to expense, and will be found one of the handsomest specimens of typographical execution as yet presented in this country. Copies will be sent to any address, by mail, free of postage, on receipt of nine cents in stamps. Catalogues of our numerous publications in miscellaneous and educational litera- ture forwarded on application. TWO MEDICAL PERIODICALS, FREE OF POSTAGE, FOR FIVE DOLLARS PER ANNUM. THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES, subject to postage, when not paid for in advance,.......$5 00 THE MEDICAL NEWS AND LIBRARY, invariably in advance, - - 1 00 or, both periodicals furnished, free of postage, for Five Dollars remitted in advance. THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES, Edited by ISAAC HAYS, M. D., is published Quarterly, on the first of January, April, July, and October. Each number contains at lea*t two hundred and eighty large octavo pages, handsomely and appropriately illustrated, wherever necessary. It has now been issued regularly for more than thirty-five years, and it has been under the control of the present editor for more than a quarter of a century. Throughout this lone neriod it has maintained its position in the highest rank of medical periodicals both at home and abroad and has received the cordial support of the entire profession in this country. Its list of rnllahontors will be found to contain a large number of the most distinguished names of the pro- fession in every section of the United States, rendering the department devoted to ORIGINAL COMMUNICATIONS fMll nf varied and important matter, of great interest to all practitioners. A. the aim of the Journal, however, is to combine the advantages presented by all the different rarieties of periodicals, in its 2 BLANCHARD & LEA'S MEDICAL REVIEW DEPARTMENT will be found extended and impartial reviews of all important new work*, presenting subjects of novelty and interest, together with very numerous BIBLIOGRAPHICAL NOTICES, including nearly all the medical publications of the day, both in this country and Great Britain, witll a choice selection of the more important continental works. This is followed by the QUARTERLY SUMMARY, being a very full and complete abstract, methodically arranged, of the IMPROVEMENTS AND DISCOVERIES IN TUE MEDICAL SCIENCES, This department of the Journal, so important to the practising physician, is the object of especial care on the part of the editor. It is classified and arranged under different heads, thus facilitating the researches of the reader in pursuit of particular subjects, and will be found to present a very full and accurate digest of all observations, discoveries, and inventions recorded in every branch of medical science. The very extensive arrangements of the publishers are such as to afford to the editor complete materials for this purpose, as he not only regularly receives ALL THE AMERICAN MEDICAL AND SCIENTIFIC PERIODICALS, but also twenty or thirty of the more important Journals issued in Great Britain and on the Conti- nent, thus enabling him to present in a convenient compass a thorough and complete abstract of everything interesting or important to the physician occurring in any part of the civili2ed world. To their old subscribers, many of whom have been on iheir list for twenty or thirty years, the publishers feel that no promises for the future are necessary; but those who may desire for the first time to subscribe, can rest assured that no exertion will be spared to maintain the Journal in the high position which it has occupied for so long a period. By reference to the terms it will be seen that, in addition to this large amount of valuable and practical information on every branch of medical science, the subscriber, by paying in advance, becomes entitled, without further charge, to THE MEDICAL NEWS AND LIBRARY, a monthly periodical of thirty-two large octavo pages. Its "News Department" presents the current information of the day, while the "Library Department" is devoted to presenting stand- ard works on various branches of medicine. Within a few years, subscribers have thus received, without expense, the following works which have passed through its columns:— WATSON'S LECTURES ON THE PRACTICE OF PHYSIC. BRODIE'S CLINICAL LECTURES ON SURGERY. TODD AND BOWMAN'S PHYSIOLOGICAL ANATOMY AND PHYSIOLOGY OF MAN. WEST'S LECTURES ON THE DISEASES OF INFANCY AND CHILDHOOD. MALGAIGNE'S OPERATIVE SURGERY, with wood-cuts. SIMON'S LECTURES ON GENERAL PATHOLOGY. BENNETT ON PULMONARY TUBERCULOSIS, with wood-cuts, WEST ON ULCERATION OF THE OS UTERI, and BROWN ON THE SURGICAL DISEASES OF FEMALES, with wood-cuts. While in the number for July, 1856, was commenced a new and highly important work, which is continued throughout 1857. WEST'S LECTURES ON THE DISEASES OF WOMEN. The very favorable reception accorded by the profession to the valuable "Lectures on thb Diseases of Children," by the same author, which likewise appeared in this periodical, has in- duced the publishers to secure the present work for their subscribers, from advance sheets, supplied by the author. The very high reputation of Dr. West, and the ungual clinical advantages which he has enjoyed, sufficiently indicate the practical value of a systematic work from his pen on so important a subject. The publishers, therefore, trust that its appearance in the " News" will afford entire satisfaction to their numerous subscribers, who will thus receive it free of all expense. fjjT For a more extended advertisement, see p. 32. It will thus be seen that for the small sum of FIVE DOLLARS, paid in advance, the subscriber will obtain a Quarterly and a Monthly periodical, EMBRACING ABOUT FIFTEEN HUNDRED LARGE OCTAVO PAGES, mailed to any part of the United States, free of postage. These very favorable terms are now presented by the publishers with the view of removing all difficulties and objections to a full and extended circulation of the Medical Journal to the office of every member of the profession throughout the United States. The rapid extension of mail facili- ties will now place the numbers before subscribers with a certainty and dispatch not heretofore attainable; while by the system now proposed, every subscriber throughout the Union is placed upon an equal footing, at the very reasonable price of Five Dollars for two periodicals, without further expense. Those subscribers who do not pay in advance will bear in mind that their subscription of Five Dollars will entitle them to the Journal only, without the News, and that they will be at the expense of their own postage on the receipt of each number. The advantage of a remittance when order- ing the Journal will thus be apparent. As the Medical News and Library is in no case sent without advance payment, its subscribers will always receive it free of postage. Remittances of subscriptions can be mailed at our risk, when a certificate is taken from the Post- master that the money is duly inclosed and forwarded. Address BLANCHARD & LEA, Philadelphia. AND SCIENTIFIC PUBLICATIONS. 3 ALLEN (J. M.), M. D., Professor of Anatomy in the Pennsylvania Medical College, &.C THE PRACTICAL ANATOMIST; or, The Student's Guide in the Dissecting- ROOM. With 266 illustrations. In one handsome royal 12mo. volume, of over 600 pages, lea- ther. $2 25. (Now Ready.) In the arrangement of this work, the author has endeavored to present a complete and thorough course of directions in a clearer and more available form for practical use, than has as yet been accomplished. The chapters follow each other in the order in which dissections are usually con- ducted in this country, and as each region is taken up, every detail regarding it is fully described and illustrated, so that the student is not interrupted in his labors, by the necessity of referring from one portion of the volume to another. However valuable may be the " Dissector's Guides" which we, of late, have had occasion to notice, we feel confident that the work of Dr. Allen is superior to any of them. We believe with the author, that none is so fully illustrated as this, and the arrangement of the work is such as to facilitate the labors of the student in acquiring a thorough practical knowledge of Anatomy. We most cordi- ally recommend it to their attention.— Western Lan- cet,Dee. 1856. We believe it to be one of the most useful works upon the subject ever written. It is handsomely illustrated, well printed, and will be found of con- venient size for use in the dissecting-room.—Med. Examiner, Dec. 1856. From Prof. J. S. Davis, University of Va. I am not acquainted with any work that attains so fully the object which it proposes. From C. P. Fanner, M. D., Demonstrator, Uni- versity of Michigan. I have examined the work briefly, but even this examination has convinced me that it is an excellent guide for the Dissector. Its illustrations are beau- tiful, and more than I have seen in a woik of this kind. I shall take great pleasure in recommending it to my classes as the text-book of the dissecting- room. ANALYTICAL COMPENDIUM OF MEDICAL SCIENCE, containing Anatomy, Physiology, Surgery, Midwifery, Chemistry, Materia Medica, Therapeutics, and Practice of Medicine. By John Neill, M. D., and F. G. Smith, M. D. New and enlarged edition, one thick volume royal 12mo. of over 1000 pages, with 374 illustrations. I3^~ See Neill, p. 24. ABEL (F. A.), F. C.S. AND C. L. BLOXAM. HANDBOOK OF CHEMISTRY, Theoretical, Practical, and Technical; with a Piecommendatory Preface by Dr. Hofmann. In one large octavo volume, extra cloth, of 662 pages, with illustrations. $3 25. It must be understood that this is a work fitted for the earnest student, who resolves to pursue for him- self a steady search into the chemical mysteries of creation. For such a student the ' Handbook' will prove an excellent guide, since he will find in it, not merely the approved modes of analytical investi- gation, but most descriptions of the apparatus ne- cessary, with such manipulatory details as rendered Faraday's ' Chemical Manipulations' so valuable at the time of its publication. Beyond this, the im- portance of the work is increased by the introduc- tion of much of the technical chemistry of the manu- factory.—Dr. Hofmann's Preface. ASHWELL (SAMUEL), M. D., Obstetric Physician and Lecturer to Guy's Hospital, London. A PRACTICAL TREATISE ON THE DISEASES PECULIAR TO WOMEN. Illustrated by Cases derived from Hospital and Private Practice. Third American, from the Third and revised London edition. In one octavo volume, extra cloth, of 528 pages, f 3 00. The most able, and certainly the most standard and practical, work on female diseases that we have yet seen.—Medico-Chirurgical Review. The most useful practical work on the subject in the English language. — Boston Med. and Surg. Journal. ARNOTT (NEILL), M. D. ELEMENTS OF PHYSICS; or Natural Philosophy, General and Medical. Written for universal use, in plain or non-technical language. A new edition, by Isaac Hays, M. D. Complete in one octavo volume, leather, of 484 pages, with about two hundred illustra- tions. $2 50. _________. BUDD (GEORGE), M. D., F. R. S., Professor of Medicine in King's College, London. ON DISEASES OF THE LIVER. Second American, from the second and -.*.\«.™~a T «nHnn edition. In one very handsome octavo volume, extra cloth, with four beauti- fully TolorecI plates, and numerous wood-cuts, pp.468. $3 00. P v vears Dr. Budd's work must be the I the subject has been taken up by so able and experi- X or many y - ' mass 0f British practitioners enced a physician.—British and Foreign Medico- Z thehepatic diseases; and it is satisfactory that I Chirurgical Review. BY THE SAME AUTHOR. ON THE ORGANIC DISEASES AND FUNCTIONAL DISORDERS OF THE STOMACH. In one neat octavo volume, extra cloth. $1 50. From the high position occupied by Dr. Budd as . fZJhec a writer, and a practitioner, it is almost SeeXss tos7ate that the present book may be coa- sted with great advantage. It is written in an easy style, the subjects are well arranged, and the practi- cal precepts, both of diagnosis and treatment, denote the character of a thoughtful and experienced phy- sician.—London Med. Times and Gazette, Deo. 1856. 4 BLANCHARD & LEA'S MEDICAL BROWN (ISAAC BAKER), Surgeon-Accoucheur to St. Mary's Hospital, &c. ON SOME DISEASES OF WOMEN ADMITTING OF SURGICAL TREAT- MENT. With handsome illustrations. One vol. 8vo., extra cloth. (Now Ready.) $160. Mr. Brown has earned for himself a high reputa- tion in the operative treatment of sundry diseases and injuries to which females are peculiarly subject. We can truly say of his work that it is an important addition to obstetrical literature. The operative suggestions and contrivances which Mr. Brown de- scribes, exhibit much practical sagacity and skill, BLAKISTON'S PRACTICAL OBSERVATIONS ON CERTAIN DISEASES OF THE CHEST, and on the Principles of Auscultation. In one vol., cloth, 8vo pp.384. $1 25. BURROWS ON DISORDERS OF THE CERE- BRAL CIRCULATION, and on the Connection between the Affections of the Brain and Diseases of the Heart. In one 8vo. vol., extra cloth, with colored plates, pp. 216. 81 25. BEALE ON THE LAWS OF HEALTH IN RE- LATION TO MIND AND BODY. A Series of Letters from an old Practitioner to a Patient. In one volume, royal 12mo., extra cloth, pp. 296. 80 cents BUSHNAN'S PHYSIOLOGY OF ANIMAL AND I and merit the careful attention of every surgeon- accoucheur.—Association Journal. We have no hesitation in recommending this book to the careful attention of all surgeons who make female complaints a part of their study and practice. —Dublin Quarterly Journal. VEGETABLE LIFE; a Popular Treatise on the Functions and Phenomena of Organic Life. In one handsome royal 12mo. volume, extra cloth, with over 100 illustrations, pp.234. 80 cents. BUCKLER ON THE ETIOLOGY, PATHOLOGY, AND TREATMENT OF FIBRO-BRONCHI- TIS AND RHEUMATIC PNEUMONIA. In one 8vo. volume, extra cloth, pp. 150. $1 25. BLOOD AND URINE (MANUALS ON). BY JOHN WILLIAM GRIFFITH, G. OWEN REESE, AND ALFRED MARKWICK. One thick volume, royal 12mo., extra cloth, with plates, pp.460. SI 25. BRODIE'S CLINICAL LECTURES ON SUR- I GERY. 1 vol. 8vo., cloth. 350 pp. $125. BENNETT (J. HUGHES), M.D., F. R. S. E., Professor of Clinical Medicine in the University of Edinburgh, &c. THE PATHOLOGY AND TREATMENT OF PULMONARY TUBERCU- LOSIS, and on the Local Medication of Pharyngeal and Laryngeal Diseases frequently mistaken for or associated with, Phthisis. In one handsome octavo volume, extra cloth, with beautilul wood-cuts. pp. 130. (Lately Issued.) $1 25. BENNETT (HENRY), M. D. A PRACTICAL TREATISE ON INFLAMMATION OF THE UTERUS, ITS CERVIX AND APPENDAGES, and on its connection with Uterine Disease. Fourth American, from the third and revised London edition. To which is added (July, 1856), a Review of the Present State of Uterine Pathology. In one neat octavo volume, extra cloth, of 500 pages, with wood-cuts. $2 00. The addition of the "Review" presents the most recent aspects of the questions discussed in this well-known work, bringing it down to the latest moment. This edition has been carefully revised and altered, | When, a few years back, the first edition of the and various additions have been made, which render present work was published, the subject was oneal- it more complete, and, if possible, more worthy of i most entirely unknown to the obstetrical celebrities the high appreciation in which it is held by the i of the day ; and even now we have reason to know medical profession throughout the world. A copy that the bulk of the profession are not fully alive to should be in the possession of every physician.— the importance and frequency of the disease of which Charleston Med. Journal and Review. it takes cognizance. The present edition is so much We are firmly of opinion that in proportion as i knowledge of uterine diseases becomes more appre We are firmly of opinion that in proportion as a enlarged, altered, and improved, that it can scarcely .f uterine diseases becomes more appre- be considered the same work.—Dr. Ranking'* Ab- ciated, tfiis work will be proportionably established , stract. as a text-book in the profession.—The Lancet. ALSO, FOR SALE SEPARATE, A REVIEW OF THE PRESENT STATE OF UTERINE PATHOLOGY. 1 small vol. 8vo. 50 cents. BIRD (GOLDING), A. M., M. D., 8cc. URINARY DEPOSITS: THEIR DIAGNOSIS, PATHOLOGY, AND THERAPEUTICAL INDICATIONS. A new and enlarged American, from the last improved London edition. With over sixty illustrations. In one royal 12mo. vol, extra cloth, pp.372. $130. It can scarcely be necessary for us to say anything of the merits of this well-known Treatise, which so admirably brings into practical application the re- sults of those microscopical and chemical researches regarding the physiology and pathology of the uri- nary secretion, which nave contributed so much to the increase of our diagnostic powers, and to the extension and satisfactory employment of our thera- peutic resources. In the preparation of this new edition of his work, it is obvious that Dr. Golding Bird has spared no pains to render it a faithful repre- sentation of the present state of scientific knowledge on the subject it embraces.— The British and Foreign Medico-Chirurgical Review. BY THE SAME AUTHOR. ELEMENTS OF NATURAL PHILOSOPHY; being an Experimental Intro- duction to the Physical Sciences. Illustrated with nearly four hundred wood-cuts. From the third London edition. In one neat volume, royal 12mo, extra cloth. pp.402. $125. AND SCIENTIFIC PUBLICATIONS. b BARLOW (GEORGE H.), M.D. Physician to Guy's Hospital, London, &c. A MANUAL OF THE PRACTICE OF MEDICINE. With Additions by D F. Condie, M. D., author of " A Practical Treatise on Diseases of Children," &c. In one hand Borne octavo volume, leather, of over 600 pages. (4 new work, just issued, 1856.) $2 75. We most emphatically commend it to the attention of the profession, as deserving their confidence—a depository of practical knowledge, from which they may draw with great benefit.—Cincinnati Med. Ob- server, Mar. 1856 The student has long been in want of a good ele- mentary work on the Practice of Medicine. In Dr. Barlow's Manual that want is supplied ; and we have no question that it will at once be installed as the favorite text-book in all Medical Schools.— Medical Times and Gazette. We recommend Dr. Barlow's Manual in the warm- est manner as a most valuable vade-mecum. We have had frequent occasion to consult it, and have found it clear, concise, practical, and sound. It is eminently a practical work, containing all that is essential, and avoiding useless theoretical discus- sion. The work supplies what has been for some time wanting, a manual of practice based upon mo- dern discoveries in pathology and rational views of treatment of disease. It is especially intended for the use of students and junior practitioners, but it will be found hardly less useful to the experienced physician. The American editor has added to the work three chapters—on Cholera Infantum, Yellow Fever, and Cerebro-spinal Meningitis. These addi- tions, the two first of which are indispensable to a work on practice destined for the profession in this country, are executed with great judgment and fi- delity, by Dr. Condie, who has also succeeded hap- pily in imitating the conciseness and clearness of style which are such agreeable characteristics of the original book.—Boston Med. and Surg. Journal. BARTLETT (ELISHA), M. D. THE HISTORY, DIAGNOSIS, AND TREATMENT OF THE FEVERS OF THE UNITED STATES. A new and revised edition. By Alonzo Clark, M. D., Prof. of Pathology and Practical Medicine in the N. Y. College of Physicians and Surgeons, &c. In one octavo volume, of six hundred pages, extra cloth. (Now Ready.) Price $3 00. The position which this work has obtained as one of our medical classics, renders unnecessary any remark further than to say that the editor, in executing the task assigned to him by the late author, has endeavored to render the work a faithfnl exposition of the subject in its most advanced condition. To effect this, a considerable amount of matter has been introduced, but by a slight enlargement of the page it has been accommodated without unduly increasing the bulk of the volume. The reputation of the editor as an accurate observer and philosophical writer is sufficient guarantee that, in his hands, the work will fully maintain its former character. It is the best work on fevers which has emanated from the American press, and the present editor has carefully availed himself of all information exist- ing upon the subject in the Old and New World, so that the doctrines advanced are brought down to the latest date in the progress of this department of Medical Science.—London Med. Times and Gazette, May 2, 1857. This excellent monograph on febrile disease, has stood deservedly high since its first publication. It will be seen that ithas now reached its fourth edi- tion under the supervision of Prof. A. Clark, a gen- tleman who, from the nature of his studies and pur- suits, is well calculated to appreciate and discuss the many intricate and difficult questions in patho- logy. His annotations add much to the interest of the work, and have brought it well up to the condi- tion of the science as it exists at the present day in regard to this class of diseases.—Southern Med. and Surg. Journal, Mar. 1857. It is a work of great practical value and interest, containing much that is new relative to the several diseases of which it treats, and, with the additions of the editor, is fully up to the times. The distinct- ive features of the different forms of fever are plainly and forcibly portrayed, and the lines of demarcation carefully and accurately drawn, and to the Ameri- can practitioner is a more valuable and safe guide than any work on fever extant.—Ohio Med. and Surg. Journal, May, 1857. The plan of the work is exceedingly compact and comprehensive. The style of the author is clear, his reasoning logical, and his deductions philoso- phical, while the spirit that pervades the work is, in the main, unexceptionable. The frequent addi- tions by the editor, are what might be looked for from their distinguished source, able, judicious, and timely. We heartily commend it to the attention of our readers as the only work on fevers that is fully adapted to this country and climate. We predict for the present edition even a more rapid sale than the former ones.—N. J. Med. Reporter, Mar. 1857. BOWMAN (JOHN E.), M.D. PRACTICAL HANDBOOK OF MEDICAL CHEMISTRY. Second Ame- rican, from the third and revised English Edition. In one neat volume, royal 12mo., extra cloth, with numerous illustrations, pp.288. $125. BY THE SAME AUTHOR. INTRODUCTION TO PRACTICAL CHEMISTRY, INCLUDING ANA- LYSIS Second American, from the second and revised London edition. With numerous illus- trations. In one neat vol., royal 12mo., extra cloth, pp. 350. $1 25. CURLING (T. B.), F. R.S., Surgeon to the London Hospital, President of the Hunterian Society, &c. A PRACTICAL TREATISE ON DISEASES OF THE TESTIS, SPERMA- TIC CORD AND SCROTUM. Second American, from the second and enlarged linglish edi- tion In one handsome octavo volume, extra cloth, with numerous illustrations, pp. 420. (Just Issued, 1856.) $2 00. ... v , Tn the reviaed English edition, of which this is a reprint, the author, for want of space, omitted th Anatomical Introduction. By a more condensed style of printing, room has been found in the l recent condition of the subject, while the very handsome series of illustra- tion* introduced, representing such pathological conditions as can be accurately portrayed, present a novel feature, and afford valuable assistance to the young practitioner. Such additions as ap- peared desirable for the American student have been made by the editor, Dr. Condie, while a marked improvement in the mechanical execution keeps pace with the advance in all other respects which the volume has undergone, while the price has been kept at the former very moderate rate. A few notices of the former edition are subjoined:— We now regretfully take leave of Dr. Churchill's book. Had our typographical limits permitted, we should gladly have borrowed more from its richly stored pages. In conclusion, we heartily recom- mend it to the profession, and would at the same time express our firm conviction that it will not only add to the reputation of its author, but will prove a work of great and extensive utility to obstetric practitioners.—Dublin Medical Press. Former editions of this work have been noticed in previous numbers of the Journal. The sentiments of high commendation expressed in those notices, have only to be repeated in this; not from the fact that the profession at large are not aware of the high merits which this work really possesses, but from a desire to see the principles and doctrines therein contained more generally recognized, and more uni- versally carried out in practice.—N. Y. Journal of Medicine. We know of no author who deserves that appro- bation, on "the diseases of females," to the same extent that Dr. Churchill does. His, indeed, is the only thorough treatise we know of on the subject; and it may be commended to practitioners and stu- dents as a masterpiece in its particular department. The former editions of this work have been com- mended strongly in this journal, and they have won their way to an extended, and a well-deserved popu- This fifth edition, before us, is well calcu- i maintain Dr. Churchill's high reputation. larity. lated to i It was revised and enlarged by the author, for his American publishers, and it seems to us that there is scarcely any species of desirable information on its subjects that may not be found in this work.—The Western Journal of Medicine and Surgery. We are gratified to announce a new and revised edition of Dr. Churchill's valuable work on the dis- eases of females We have ever regarded it as one of the very best works on the subjects embraced within its scope, in the English language; and the present edition, enlarged and revised by the author, renders it still more entitled to the confidence of the profession. The valuable notes of Prof. Huston have been retained, and contribute, in no small de- gree, to enhance the value of the work.' It is a source of congratulation that the publishers have permitted the author to be, in this instance, his own editor, thus securing all the revision which an author alone is capable of making.—The Western Lancet. Asa comprehensive manual for students, or a work of reference for practitioners, we only speak with common justice when we say that it surpasses any other that has ever issued on the same sub- ject from the British press.—The Dublin Quarterly Journal. DICKSON (S. H.), M. D., Professor of Institutes and Practice of Medicine in the Medical College of Sonth Carolina. ELEMENTS OF MEDICINE; a Compendious View of Pathology and Thera- peutics, or the History and Treatment of Diseases. In one large and handsome octavo volume, of 750 pages, leather (Lately Issued.) $3 75. As an American text-book on the Practice of Medicine for the student, and as a condensed work of reference for the practitioner, this volume will have strong claims on the attention of the profession. Few physicians have had wider opportunities than the author for observation and experience, and few perhaps have used them better. As the result of a life of study and practice, therefore, the present volume will doubtless be received with the welcome it deserves. This book is eminently what it professes to be; a distinguished merit in these days. Designed for Teachers and Students of Medicine," and admira- bly suited to their wants, we think it will be received, on its own merits, with a hearty welcome.—Boston Med. and Surg. Journal. Indited by one of the most accomplished writers of our country, as well as by one who has long held a high position among teachers and practitioners of medicine, this work is entitled to patronage and careful study. The learned author has endeavored to condense in this volume most of the practical matter contained in his former productions, so as to adapt it to the use of those who have not time to devote to more extensive works.—Southern Med. and Surg. Journal. We can strongly recommend Dr. Dickson's work to our readers as one of interest and practical utility, well deserving of a place in their libraries as a book of referenct ; and we especially commend the first part as presenting an admirable outline of the princi- ples of medicine.—Dublin Quarterly Journal, Feb. 1856 This volume, while as its title denotes it is a compendious view, is also a comprehensive system of oractiee. perspicuously and pleasantly written, ana Admirably suited to engage the interest, and in- struct the reader.—Peninsular Journal of Medicine, Jan. 1SS6. Prof. Dickson's work supplies, to a great extent, a desideratum long felt in American medicine.—iV. O. Med. and Surg. Journal, Estimating this work according to the purpose for which it is designed, we must think highly of its merits, and we have no hesitation in predicting for it a favorable reception by both students and teachers. Not professing to be a complete and comprehensive treatise, it will not be found full in detail, nor filled with discussions of theories and opinions, but em- bracing all that is essential in theory and practice, it is admirably adapted to the wants of the American student. Avoiding all that is uncertain, it presents more clearly to the mind of the reader that which is established and verified by experience. The varied and extensive reading of the author is conspicuously apparent, and all the recent improvements and dis- coveries in therapeutics and pathology are chroni- cled in its pages.—Charleston Med. Journal. In the first part of the work the subject of gene- ral pathology is presented in outline, giving a btau- tiful picture of its distinguishing features, and throughout the succeeding chapters we find that he has kept scrupulously within the bounds of sound reasoning and legitimate deduction. Upon the whole, we do not hesitate to pronounce it a superior work in its class, and that Dr. Dickson merits a place in the first rank of American writers.—Western Lancet. AND SCIENTIFIC PUBLICATIONS. n DRUITT (ROBERT), M.R. C.S., &c. THE PRINCIPLES AND PRACTICE OF MODERN SURGERY. A new American, from the improved London edition. Edited by F. W. Sargent, M. D., author of " Minor Surgery," &c. Illustrated with one hundred and ninety-three wood-engravings. In one very handsomely printed octavo volume, leather, of 576 large pages. $3 00. Dr. Druitt's researches into the literature of his subject have been not only extensive, but well di- rected ; the most discordant authors are fairly and impartially quoted, and, while due credit is given to each, their respective merits are weighed with an unprejudiced hand. The grain of wheat is pre- served, and the chaff is unmercifully stripped off. The arrangement is simple and philosophical, and the style, though clear and interesting, is so precise, that the book contains more information condensed into a few words than any other surgical work with which we are acquainted.—London Medical Times and Gazette. No work, in our opinion, equals it in presenting so much valuable surgical matter in so small a compass.—St. Louis Med. and Surgical Journal. Druitt's Surgery is too well known to the Ameri- can medical profession to require its announcement anywhere. Probably no work of the kind has ever been more cordially received and extensively circu- lated than this. The fact that it comprehends in a comparatively small compass, all the essential ele- ments of theoretical and practical Surgery—that it is found to contain reliable and authentic informa- tion on the nature and treatment of nearly all surgi- cal affections—is a sufficient reason for the liberal patronage it has obtained. The editor, Dr. F. W. Sargent, has contributed much to enhance the value of the work, by such American improvements as are calculated more perfectly to adapt it to our own views and practice in this country. It abounds everywhere with spirited and life-like illustrations, which to the young snrgeon, especially, are of no minor consideration. Every medical man frequently needs just such a work as this, for immediate refer- ence in moments of sudden emergency, when he has not time to consult more elaborate treatises.—The Ohio Medical and Surgical Journal. The author has evidently ransacked every stand- ard treatise of ancient and modern times, and all that is really practically useful at the bedside will be found in a form at once clear, distinct, and interest- ing.—Edinburgh Monthly Medical Journal. Druitt's work, condensed, systematic, lucid, and practical as it is, beyond most works on Surgery accessible to the American student, has had much currency in this country, and under its present au- spices promises to rise to yet higher favor.—The Western Journal of Medicine and Surgery. The most accurate and ample resume of the pre- sent state of Surgery that we are acquainted with.— Dublin Medical Journal. A better book on the principles and practice of Surgery as now understood in England and America, has not been given to the profession.—Boston Medi- cal and Surgical Journal. An unsurpassable compendium, not only of Sur- gical, but of Medical Practice.—London Medical Gazette. This work merits our warmest commendations, and we strongly recommend it to young surgeons as an admirable digest of the principles and practice of modern Surgery.—Medical Gazette. It maybe said with truth that the work of Mr, Druitt affords a complete, though brief and con- densed view, of the entire field of modern surgery. We know of no work on the same subject having the appearance of a manual, which includes so many topics of interest to the surgeon ; and the terse man- ner in which each has been treated evinces a most enviable quality of mind on the part of the author, who seems to have an innate power of searching out and grasping the leading facts and features of the most elaborate productions of the pen. It is a useful handbook for the practitioner, and we should deem a teacher of surgery unpardonable who did not recommend it to his pupils. In our own opinion, it is admirably adapted to the wants of the student.— Provincial Medical and Surgical Journal. DUNGLISON, FORBES, TWEEDIE, AND CONOLLY. THE CYCLOPAEDIA OF PRACTICAL MEDICINE: comprising Treatises on the Nature and Treatment of Diseases, Materia Medica, and Therapeutics, Diseases of Women and Children, Medical Jurisprudence, &c. &c. In four large super-royal octavo volumes, of 3254 double-columned pages, strongly and handsomely bound, with raised bands. $12 00. *** This work contains no less than four hundred and eighteen distinct treatises, contributed by Sixty-eight distinguished physicians, rendering it a complete library of reference for the country practitioner The most complete work on Practical Medicine extant; or, at least, in our language.—Bujfalo Medical and Surgical Journal. For reference, it is above all price to every prac- titioner.—Western Lancet. One of the most valuable medical publications of the day__as a work of reference it is invaluable.— Western Journal of Medicine and Surgery. It has been to us, both as learner and teacher, a work for ready and frequent reference, one in which modern English medicine is exhibited in the most advantageous light.—Medical Examiner. We rejoice that this work is to be placed within the reach of the profession in this country, it being unquestionably one of very great value to the prac- titioner. This estimate of it has not been formed from a hasty examination, but after an intimate ac- quaintance derived from frequent consultation of it during the past nine or ten years. The editors are practitioners of established reputation, and the list of contributors embraces many of the most eminent professors and teachers of London, Edinburgh, Dub- lin, and Glasgow. It is, indeed, the great merit of this work that the principal articles have been fur- nished by practitioners who have not only devoted especial attention to the diseases about which they have written, but have also enjoyed opportunities for an extensive practical acquaintance with them, and whose reputation carries the assurance of their competency justly to appreciate the opinions of others, while it stamps their own doctrines with high and just authority.—American Medical Journ. DEWEES'S COMPREHENSIVE SYSTEM OF MIDWIFERY. Illustrated by occasional cases and many engravings. Twelfth edition with the nnthor's last improvements and corrections In one octavo volume, extracloth.of 600 pages. *3 20. n.,wl?P,,s TREATISE ON THE PHYSICAL DAND MED^ALTREATMENT OF CHILD- REN Tenth edition. In one volume, octavo, extra cloth, 548 pages. »2 80. DEWEES'S TREATISE ON THE DISEASES r»F FKMALES. Tenth edition. In one volume, ocW exua ctoth, 532 pages, with plates. $3 00. DANA ON ZOOPHYTES AND CORALS. In one volume, imperial quarto, extra cloth, with wood- cuts. $15 00. Also, AN ATLAS, in one volume, imperial folio, with sixty-one magnificent colored plates. Bound in half morocco. $30 00. DE LA BECHE'S GEOLOGICAL OBSERVER. In one very large and handsome octavo volume, ex- tra cloth, of 700 pages, with 300 wood-cuts. $4 00. FRICK ON RENAL AFFECTIONS; their Diag- nosis and Pathology. With illustrations. One volume, royal 12mo., extra cloth. 75 cents. 12 BLANCHARD & LEA'S MEDICAL DUNGLISON (ROBLEY), M. D., Professor of Institutes of Medicine in the Jefferson Medical College, Philadelphia. MEDICAL LEXICON; a Dictionary of Medical Science, containing a concise Explanation of the various Subjects and Terms of Physiology, Pathology, Hygiene, Therapeutics, Pharmacology, Obstetrics, Medical Jurisprudence, &c. With the French and other Svnonymes; Notices of Climate and of celebrated Mineral Waters; Formulae for various Officinal, Empirical, and Dietetic Preparations, etc. A new edition, revised, is now ready. In one very thick octavo volume, of over nine hundred large double-columned pages, strongly bound in leather, with raised bands. $4 00. Every successive edition of this work bears the marks of the industry of the author, and ol his determination to keep it fully on a level with the most advanced state of medical science. Thus nearly fifteen thousand words have been added to it within the last few years. As a complete Medical Dictionary, therefore, embracing over FIFTY THOUSAND DEFINITIONS, in all the branches of the science, it is presented as meriting a continuance of the great favor and popularity which have carried it, within no very long space of time, through so many editions. Every precaution has been taken in the preparation of the present volume, to render its mecha- nical execution and typographical accuracy worlhy of its extended reputation and universal use. The very extensive additions have been accommodated, without materially increasing the bulk of the volume, by the employment of a small but exceedingly clear type, cast for this purpose. The press has been watched with great care, and every effort used to insure the verbal accuracy so ne- cessary to a work of this nature. The whole is printed on fine white paper; and, while thus exhi- biting in every respect so great an improvement over former issues, it is presented at the original exceedingly low price. We welcome it cordially ; it is an admirable work, | readers to its peculiar merits; and we need do and indispensable to all literary medical men. The j little more than state, in reference to the present labor which has been bestowed upon it is something I reissue, that, notwithstanding the large additions prodigious. The work, however, has now been previously made to it, no fewer than four thou- done, and we are hnppy in the thought that no hu- i sand terms, not to be found in the preceding edi- man being will have again to undertake the same | tion, are contained in the volume before us.— gigantic task. Revised and corrected from time to I Whilst it is a wonderful monument of its author's time, Dr. Dunglison's "Medical Lexicon" will last erudition and industry, it is also a work of great for centuries.—British and Foreign Med.-Chirurg. I practical utility, as we can testify from our own Review. j experience; for we keep it constantly within our The fact that this excellent and learned work has i reach> and make very frequent reference to it, passed through eight editions, and that a ninth is i nearly always finding in it the information we seek. rendered necessary by the demands of the public, I —British and Foreign Med.-Chirurg. Review. affords a sufficient evidence of the general apprecia- : It nag the rare merit that it certainly has no rival tion of Dr. Dunglison's labors by the medical pro- , in the Ensligh language for accuracy and extent fession in England and America. It is a book which of references. The terms generally include short will be of great service to the student, in teaching physiological and pathological descriptions, so that, him the meaning of all the technical terms used in a8 the autnor justly observes, the reader does not medicine, and will be of no less use to the practi- poggegs in this work a mere dictionary, but a book, tioner who desires to keep himself on a level with I which whiie it instructs him in medical etymo- the advance of medical science.—London Medical logV) f\,rnisneg him with a large amount of useful Times and Gazette. information. The author's labors have been pro- In taking leave of our author, we feel compelled perly appreciated by his own countrymen ; and we to confess that his work bears evidence of almost, can only confirm their judgment, by recommending incredible labor having been bestowed upon its com- this most useful volume to the notice of our cisat- position.—Edinburgh Journal of Med. Science. | lantic readers. No medical library will be complete A miracle of labor and industry in one who has j without it.—London Med. Gazette. written able and voluminous works on nearly every j It ig eertainly more complete and comprehensive branch of medical science. There could be no more i than with which we are acquainted in the useful book to the student or practitioner, in the English language. Few, in fact, could be found present advancing age, than one in which would be betfer aualiffed than Dr. Dunglison for the produc- found, in addition to the ordinary meaning and den- tion 0f such a work. Learned, industrious, per- vationof medical terms—so many of which are of | 8evering, and accurate, he brings to the task all modern introduction—concise descriptions of their | the pec°u'li!ir tHlents neCessary for its successful explanation and employment: andall this and much rfoKrmiince; while at the same time, his fami- more is contained in the volume before us. It is liarit wlth t'he writingg 0f the ancient and modern therefore almostas indispensably the other learned : u m./steIS of our art,'? renders him skilful to note professions as to our own. In fact, to all who may . tne exact „ of 'the geveral terms of science, have occasion_to ascertain the meaningof any word i and the various modifications which medical term belonging to the many branches of medicine. From , inolo(ry has undergone with the change of theo a careful examination of the present edition, we can vouch for its accuracy, and for its being brought quite up to thedate of publication ; the autnor states in his preface that he has added to it about four thou- sand terms, which are not to be found in the prece ries or the progress of improvement. — American Journal of the Medical Sciences. One of the most complete and copious known to the cultivators of medical science.—Boston Med. ding one.— Dublin Quarterly Journal of Medical | Journal. Scimces. | >pne most comprehensive and best English Die- On the appearance of the last edition of this I tionary of medical terms extant.—Buffalo Medical valuable work, we directed the attention of our | Journal. BY THE SAME AUTHOR. THE PRACTICE OF MEDICINE. A Treatise on Special Pathology and The- rapeutics. Third Edition. In two large octavo volumes, leather, of 1,500 pages. $6 25. Upon every topic embraced in the work the latest information will be found carefully posted up.— Medical Examiner. ferings of the race.—Boston Medical and Surgical Journal. , It is certainly the most complete treatise of which The student of medicine will find, in these two ' we have any knowledge.—Western Journal of Medi- elegant volumes, a mine of facts, a gathering of cjne anc[ Surgery. precepts and advice from the world of experience, j that will nerve him with courage, and faithfully | One of the mos lelaborate treatises of the kind direct him in his efforts to relieve the physical suf- i we have.—Southern Med. and Surg. Journal. AND SCIENTIFIC PUBLICATIONS. 13 DUNGLISON (ROBLEY), M.D., Professor of Institutes of Medicine in the Jefferson Medical College, Philadelphia. HUMAN PHYSIOLOGY. Eighth edition. Thoroughly revised and exten- sively modified and enlarged, with five hundred and thirty-two illustrations. In two large and handsomely printed octavo volumes, leather, of about 1500 pages. (Just Issued, 1856.) $7 00. In revising this work for its eighth appearance, the author has spared no labor to render it worthy a continuance of the very great favor which has been extended to it by the profession. The whole contents have been rearranged, and to a great extent remodelled ; the investigations which of late years have been so numerous and so important, have been carefully examined and incorporated, and the work in every respect has been brought up to a level with the present state of the subject. The object of the autnor has been to render it a concise but comprehensive treatise, containing the whole body of physiological science, to which the student and man of science can at all times refer with the certainty of finding whatever they are in search of, fully presented in all its aspects; and on no former edition has the author bestowed more labor to secure this result. A similar improvement will be found in the typographical execution of the volumes, which, in this respect, are superior to their predecessors. A large number of additional wood-cuts have been introduced, and the series of illustrations has been greatly modified by the substitution of many new ones for such as were not deemed satisfactory. By an enlargement of the page, these very considerable additions have been accommodated without increasing the size of the volumes to an extent to render them unwieldy. We believe that it can truly be said, no more com- plete repertory of facts upon the subject treated, ean anywhere be found. The author has, moreover, that enviable tact at description and that facility and ease of expression which render him peculiarly acceptable to the casual, or the studious reader. This faculty, so requisite in setting forth many graver and less attractive subjects, lends additional charms to one always fascinating.—Boston Med. und Surg. Journal, Sept. 1656. The most complete and satisfactory system of Physiology in the English language.—Amer. Med Journal. The best work of the kind in the English lan- guage.—Silliman's Journal. The present edition the author has made a perfect mirror of the science as it is at the present hour. As a work upon physiology proper, the science of the functions performed by the body, the student will find it all he wishes.—Nashville Journ. of Med. Sept. 1856. That he has succeeded, most admirably succeeded in his purpose, is apparent from the appearance of an eighth edit ion. It is now the great encyclopedia on the subject, and worthy of a place in every phy- sician's library.— Western Lancet, Sept. 1S56. BY THE SAME AUTHOR. GENERAL THERAPEUTICS AND MATERIA MEDICA; adapted for a Medical Text-book. New edition, much improved. With one hundred and eighty-seven illus- trations. In two large and handsomely printed octavo vols., leather, of about 1100 pages. $6 00. In this work of Dr. Dunglison,we recognize the same untiring industry in the collection and em- bodying of facts on the several subjects of which he treats, that has heretofore distinguished him, and we cheerfully point to these volumes, as two of the most interesting that we know of. In noticing the additions to this, the fourth edition, there is very little in the periodical or annual literature of the profession, published in the interval which has elapsed since the issue of the first, that has escaped the careful search of the author. As a book for reference, it is invaluable.—Charleston Med. Jour- nal and Review. It may be. said to be the work now upon the sub- jects upon which it treats.—Western Lancet. BY THE SAME AUTHOR As a text-book for students, for whom it is par- ticularly designed, we know of none superior to it.—St. Louis Medical and Surgical Journal. It purports to be a new edition, but it is rather a new book, so greatly has it been improved, both in the amount and quality of the matter which it contains.—iV. O. Medical and Surgical Journal. We bespeak for this edition, from the profession, an increase of patronage over any of its former ones, on account of its increased merit. — N. Y. Journal of Medicine. We consider this work unequalled.—Boston Med. and Surg. Journal. (A new Edition.) NEW REMEDIES, WITH FORMULA FOR THEIR PREPARATION AND ADMINISTRATION. Seventh edition, with extensive Additions. In one very large octavo volume, leather, of 770 pages. (Just Issued, May, 1856.) $3 75. Another edition of the » New Remedies" having been called for, the author has endeavored to add everything of moment that has appeared since the publication of the last edition. The chief remedial means which have obtained a place, for the first time, in this volume, either owing to their having been recently introduced into pharmacology, or to their having received novel awKons-and which, consequently, belong to the category of « New Remedies''-are the fol- l° Amf l^Caffein, Carbazotic acid, Cauterization and catheterism of the larynx and trachea, Cedron, Cerfum Chloride of bromine, Chloride of iron, Chloride of sodium Cinchonicine Cod-liver olein, Citation Eau de Pagliari, Galvanic cautery, Hydriodic ether, Hyposulphite of soda and stiver, Wt on Iodide of sodium, Nickel, Permanganate of potassa, Phosphate of lime Pumpkin Qumuha, Set Saccharine carbonate of iron and manganese, Santonin, Tellurium, and Traumatic.ne. The artfdes treated of in the former editions will be found to have undergone considerable ex- r^5on in thK in order that the author might be enabled to introduce as far as practtcable the Kts of the subsequent experience of others, as well as of his own observation and reflection; and!omakethe work still more deserving of the extended circulation w.th which the preceding ^ftions have blen favored by the profession. By an enlargement of the page, the numerous addi- ^s have blen incorporated without greatly increasing the bulk of the volume.-Preface. The great learning of the author, and his remark- able industry in pushing his researches into every One of the most useful of the author's works.- Southern Medical and Surgical Journal. This elaborate and useful volume should be found in every medical library, for as a book of re- Kce for Physicians, it is unsurpassed by any other work in existence, and the double index for SiseasTs and for remedies, will be found greatly to JSc^ its value.-JV«W York Med. Gazette. source whence information is derivable,have enabled him to throw together an extensive mass of facts and statements, accompanied by full reference to authorities; which last feature renders the work practically valuable to investigators who desire te examine the original papers.—The American Journal of Pharmacy. 14 BLANCHARD * LEA'S MEDICAL ERICHSEN (JOHN), Professor of Surgery in University College, London, &c. THE SCIENCE AND ART OF SURGERY; being a Treatise on Surgicax Injuries, Diseases, and Operations. Edited by John H. Brinton, M. D. Illustrated with three hundred and eleven engravings on wood. In one large and handsome octavo volume, of over nine hundred closely printed pages, leather, raised bands. $4 25. It is, in our humble judgment, decidedly the best book of the kind in the English language. Strange that just such books are notoftener produced by pub- lic leachers of surgery in this country and Great Britain Indeed, it is a matter of great astonishment, but no less true than astonishing, that of the many works on surgery republished in this country within the last fifteen or twenty years a- text-books for medical students, this is the only one. that even ap- proximates to the fulfilment of the peculiar wants of young men just entering upon the study of this branch of the profession.— Western Jour, of Med. and Surgery. Its value is greatly enhanced by a very copious well-arranged index. We regard this as one of the most valuable contributions to modern surgery. To one entering his novitiate of practice, we regard it the most serviceable guide which he can consult. He will find a fulnessof detail leadinghim through every step of the operation, and not deserting him until the final issue of the case is decided. For the same rea- son we recommend it to those whose routine of prac- tice lies in such parts of the country that they must rarely encounter cases requiring surgical manage- ment.—Stethoscope.. Embracing, as will be perceived, the whole snrei- cal domain, and each division of itself almost com- plete and perfect, each chapter full and explicit, each subject faithfully exhibited, we can only express ou» estimate of it in the aggregate. We consider it an excellent contribution to surgery, os probably the best single volume now extant on the subject, and with great pleasure we add it to our text-books.— Nashville Journal ef Medicine and Surgery. Prof. Erichsen's work, for its size, has not been surpassed; his nine hundred and eight pages, pro- fusely illustrated, are rich in physiological, patholo- gical, and operative suggestions, doctrines, details, and processes; and will prove a reliable resource for information, both to physician and surgeon, in the hour of peril.— N. O. Med. and Surg. Journal. We are acquainted with no other work wherein so much good sense, sound principle, and practical inferences, stamp every page.—American Lancet. ELLIS (BENJAMIN), M.D. THE MEDICAL FORMULARY: being a Collection of Prescriptions, derived from the writings and practice of many of the most eminent physicians of America and Europe. Together with the usual Dietetic Preparations and Antidotes for Poisons. To which is added an Appendix, on the Endermic use of Medicines, and on the use of Ether and Chloroform. The whole accompanied with a few brief Pharmaceutic and Medical Observations. Tenth edition, revised and much extended by Robert P. Thomas, M. D., Professor of Materia Medica in the Philadelphia College of Pharmacy. In one neat octavo volume, extra cloth, of'296 pages. (Lately Issued.) $1 75. After an examination of the new matter and the alterations, we believe the reputation of the work built up by the author, and the late distinguished editor, will continue to flourish under the auspices of the present editor, who has the industry and accu- racy, and, we would say, conscientiousness requi- site for the responsible task.—Am. Jour, of Pharm. It will prove particularly useful to students and young practitioners, as the most important prescrip- tions employed in modern practice, which lie scat- tered through our medical literature, are here col- lected and conveniently arranged for reference.— Charleston Med. Journal and Review. FOWNES (GEORGE), PH. D., &c. ELEMENTARY CHEMISTRY; Theoretical and Practical. With numerous illustrations. Edited, with Additions, by Robert Bridges, M. D. In one large royal 12mo. volume, of over 550 pages, with 181 wood-cuts We know of no better text-book, especially in the difficult department of organic chemistry, upon which it is particularly full and satisfactory. We would recommend it to preceptors as a capital " office book" for their stndents who are beginners in Chemistry. It is copiously illustrated with ex- cellent wood-cuts, and altogether admirably "got Bp.»>—JV. J. Medical Reporter. A standard manual, which has long enjoyed the reputation of embodying much knowledge in a small space. The author hasachieved the difficult task of condensation with masterly tact. His book is con- cise without being dry, and brief without being too dogmatical or general.—Virginia Med. and Surgical Journal. In leather, $ 1 50; extra cloth, $1 35. The work of Dr. Fownes has long been before the public, and its merits have been fully appreci- ated as the best text-book on chemistry now in existence. We do not, of course, place it in a rank Bupenor to the works of Brande, Graham, Torner, Gregory, or Gmelin, but we say that, as a work for students, it is preferable to any of them.—Lon- don Journal of Medicine. A work well adapted to the wants of the student. It is an excellent exposition of the chief doctrines and facts of modern chemistry. The size of the work, and still more the condensed yet perspicuous style in which it is written, absolve it from the charges very properly urged against most manuals termed popular.—Edinburgh Journal of Medical Science. FERGUSSON (WILLIAM), F. R. 3., Professor of Surgery in King's College, London, Ac. A SYSTEM OF PRACTICAL SURGERY. Fourth American, from the third and enlarged London edition. In one large and beautifully printed octavo volume, of about 700 pages, with 393 handsome illustrations, leather. $3 00. The most important subjects in connection with practical surgery which have been more recently brought under the notice of, and discussed by, the surgeons of Great Britain, are fully and dispassion- ately considered by Mr. Fergusson, and that which was before wanting has now been supplied^ so that we can now look upon it as a work on practical sur- gery instead of one on operative surgery alone. Medical Times and Gazette. No work was ever written which more nearly comprehended the necessities of the student and practitioner, and was more carefully arranged to that single purpose than this.—N. Y. Med. Journal. The addition of many new pages makes this work more than ever indispensable to the student and prac- titioner.—Banking's Abstract. Among the numerous works upon surgeTy pub- lished of late years, we know of none we value more highly than the one before us. It is perhaps the very best we have for a text-book and for ordi- nary reference, being concise and eminently practi- cal.—Southern Med. and Surg. Journal. AND SCIENTIFIC PUBLICATIONS. 15 FLINT (AUSTIN), M. D., Professor of the Theory and Practice of Medicine in the University of Louisville, &c. (An Important New Work.) PHYSICAL EXPLORATION AND DIAGNOSIS OF DISEASES AFFECT- ING THE RESPIRATORY ORGANS. In one large and handsome octavo volume, extra cloth, 636 pages. (Now Ready.) $3 00. We can only state our general impression of the high value of this work, and cordially recommend it to all. We regard it, in point both of irrangement and of the marked ability of its treatment of the sub- jects, as destined to take the first rank in works of this class. So far as our information extends, it has at present no equal. To the practitioner, as well as the student, it will be invaluable in clearing up the diagnosis of doubtful cases, and in shedding light upon difficult phenomena.—Buffalo Med. Journal. This is the most elaborate work devoted exclu- sively to the physical exploration of diseases of the lungs, with which we are acquainted in the English language. From the high standing of the author as a clinical teacher, and his known devotion, during many years, to the study of thoiacic diseases, much was to be expected from the announcement of his determination to embody in the form of a treatise, the results of his study and experience. These ex- pectations we are confident will not be disappointed. For our own part, we have been favorably impressed by a perusal of the book, and heartily recommend it to all who are desirous of acquiring a thorough ac- quaintance with the means of exploring the condi- tions of the respiratory organs by means of auscul- tation and percussion. — Boston Med. and Surg. Journal. A work of original observation of the highest merit. We recommend the treatise to every one who wishes to become a correct auscultator. Based to a very large extent upon cases numerically examined, it carries the evidence of careful studv and discrimina- tion upon every pa?e. It does credit to the author, and, through him, to the profession in this country. It is, what we cannot call every book upon auscul- tation, a readable book.—Am. Jour. Med. Sciences. FISKE FUND PRIZE ESSAYS. THE EFFECTS OF CLIMATE ON TUBERCULOUS DISEASE. By Edwin Lee, M. R. C. S., London. THE INFLUENCE OF PREGNANCY ON THE DEVELOPMENT TUBERCLES. By Edward Warren, M. D., of Edenton, N. C. Together in one neat octavo volume, extra cloth. $1 00. (Just Ready.) These two valuable Essays on Tuberculosis are reprinted by request of the Rhode Island Medi- cal Society, fron« he "American Journal of the Medical Sciences" for April and July, 1857. OF GRAHAM (THOMAS), F. R. S., Professor of Chemistry in University College, London, &c. THE ELEMENTS OF CHEMISTRY. Including the application of the Science to the Arts. With numerous illustrations. With Notes and Additions, by Robert Bridges, M. D., &c. &c. Second American, from the second and enlarged London edition. PART I. (Lately Isstied) large 8vo., 430 pages, 185 illustrations. $1 50. PART II. (Preparing) to match. __________________ GRIFFITH (ROBERT E.), M. D., &c. A UNIVERSAL FORMULARY, containing the methods of Preparing and Ad- ministering Officinal and other Medicines. The whole adapted to Physicians and Pharmaceu- tists. Second Edition, thoroughly revised, with numerous additions, by Robert P. Thomas, M. D. Professor of Materia Medica in the Philadelphia College of Pharmacy. In one larpe and handsome octavo volume, extra cloth, of 650 pages, double columns. (Just Issued.) $3 00; or bound in sheep, $3 25 It was a work requiring much perseverance, and when published was looked upon as by far the best work of its kind that had issued from the American press. Prof Thomas has certainly "improved" as well as added to this Formulary, and has rendered it additionally deserving of the confidence of pharma- ceutists and physicians.—Am. Journal of Pharmacy. We are happy to announce a new and improved edition of this, one of the most valuable and useful works that have emanated from an American pen. It would do credit to any country, and will be found of daily usefulness to practitioners of medicine; it is better adapted to their purposes than the dispensato- ries— Southern Med. and Surg. Journal. A new edition of this well-known work, edited by R. P. Thomas, M. D., affords occasion for renewing our commendation of so useful a handbook, which ought to be universally studied by medical men of evfry class, and made use of by way of reference by office pupils, as a standard authority. It has been much enlarged, and now condenses a vast amount Sf needful and necessary knowledge in small com- Saw The more of such books the better for the pro- Fusion and "he public- N. Y. Med. Gazette. It is one of the most useful books a country practi- tioner can possibly have in his possession.—Medical Chronicle. The amount of useful, every-day matter, for a prac- ticing physician, is really immense.—Boston Med. and Surg. Journal. This is a work of six hundred and fifty-one pages, embracing all on the subject of preparing and admi- nistering medicines that can be desired by the physi- cian and pharmaceutist.— Western Lancet. In short, it is a full and complete work of the kind, and should be in the hands of every physician and apothecary. 0. Med. and Surg. Journal We predict a great sale for this work, and we espe- cially recommend it to all medical teachers.—Rich- mond Stethoscope. This edition of Dr. Griffith's work has been greatly improved by the revision and ample additions of Dr. Thomas, and is now, we believe, one of the most complete works of it* kind in any language. The additions amount to about seventy pages, and no effort has been spared to include in them all the re- cent improvements which have been published in medical journals, and systematic treatises. A work of thi* kind appears to us indispensable to the physi- cian, and there is none we can more cordially recom- mend.— N. Y. Journal of Medicine. BV THE SAME AUTHOR. MFDICAL BOTANY; or, a Description of all the more important Plants used \»T Medicine and of their Properties, Uses, and Modes of Administration. In one large octavo chime extra cloth, of 704 pages, handsomely printed, with nearly 350 illustrations on wood. $3 00. 16 BLANCHARD & LEA'S MEDICAL GROSS (SAMUEL D.), M. D., Professor of Surgery in the Jefferson Medical College of Philadelphia, Ac. New Edition (Now Ready.) ELEMENTS OF PATHOLOGICAL ANATOMY. Third edition, thoroughly revised and greatly improved. In one large and very handsome octavo volume, with about three hundred and fifty beautiful illustrations, of which a large number are from original drawings. Price in extra cloth, $4 75; leather, raised bands, $5 25. The length of time which has elapsed since the appearance of the last edition of this work, and the energetic labors of the numerous investigators of pathological subjects, have so changed th« details of the science, that very extensive alterations have been found requisite in its revision, to bring it thoroughly up to the present state of the subject. In many respects this edition may there- fore be regarded as a new work. A similar improvement will likewise be found in its mechanical execution, and in the series of illustrations, which has been greatly altered and improved. In every respect it may therefore be expected to fully maintain the very high reputation which it has acquired as a sound practical text-book on all points relating to its important subject, while a considerable reduction has been made in the price. BY THE SAME AUTHOR. A PRACTICAL TREATISE ON THE DISEASES, INJURIES, AND MALFORMATIONS OF THE URINARY BLADDER, THE PROSTATE GLAND, AND THE URETHRA. Second Edition, revised and much enlarged, with one hundred and eighty- four illustrations. In one large and very handsome octavo volume, of over nine hundrr J pages. (Just Issued.) In leather, raised bands, $5 25; extra cloth, $4 75. A volume replete with truths and principles of the utmost value in the investigation of these diseases.— American Medical Journal. On the appearance of the first edition of this woTk, the leading English medical review predicted that it would have a " permanent place in the literature of Burgery worthy to rank with the best works of the present age." This prediction has been amply ful- filled. Dr. Gross's treatise has been found to sup- ply completely the want which has been felt ever since the elevation of surgery to the rank of a science, of a good practical treatise on the diseases of the bladder and its accessory organs. Philosophical in its design, methodical in its arrangement, ample and sound in its practical details, it may in truth be said to leave scarcely anything to be desired on so im- portant a subject, an<* with the additions and modi- fications resulting from future discoveries and im- provements, it will probably remain one of the most valuable works on this subject so long as the scienoe of medicine shall exist.—Boston Med. and Surg. Journal. Dr. Gross has brought all his learning, experi- ence, tact, and judgment to the task, and has pro- duced a work worthy of his high reputation. We feel perfectly safe in recommending it to our read- ers as a monograph unequalled in interest and practical value by any other on the subject in our language.—Western Journal of Med. and Surg. Whoever will peruse the vast amount of valuable practical information it contains, and which we have been unable even to notice, will, we think, agree with us, that there is no work in the English language which can make any just pretensions to be its equal.—N. Y. Journal of Medicine. BY THE SAME AUTHOR. (Just Issued). A PRACTICAL TREATISE ON FOREIGN BODIES IN THE AIR-PAS- SAGES. In one handsome octavo volume, extra cloth, with illustrations, pp. 468. $2 75. A very elaborate work. It is a complete summary conclude by recommending it to our readers, fully of the whole subject, and will be a useful book of persuaded that its perusal will afford them much reference.—British and Foreign Medico-Chirurg. practical information well conveyed, evidently de- Review. j rived from considerable experience anil deduc6C,/Yom A highly valuable book of reference on a most im- \ aTn ample collection of facts. -Dublin Quarterly portant subject in the practice of medicine. We I Journal, May, 1S55. by the same author. (Preparing.) A SYSTEM OF SURGERY j Diagnostic, Pathological, Therapeutic, and Opera- tive. With very numerous engravings on wood. GLUGE (GOTTLIEB), M. D., Professor "f Physiology and Pathological Anatomy in the Ur.it ^rsity of Brussels, Ac. AN ATLAS OF PATHOLOGICAL HISTOLOGY. Translated, with Notes and Additions, by Joseph Leidy, M. D., Professor of Anatomy in the University of Pennsylva- nia. In one volume, very large imperial quarto, extra cloth, with 320 figures, plain and coloied, on twelve copperplates. $5 00. GARDNER'S MEDICAL CHEMISTRY, for the use of Students and the Profession. In one royal 12mo. vol., ex. cloth, pp. 396, with illustrations. 61 00. HARRISONS ESSAY TOWARDS A CORRECT THEORY OF THE NERVOUS SYSTEM. In one octavo volume, leather, 292 pages. $1 50. HUGHES' CLINICAL INTRODUCTION TO THE PRACTICE OF AUSCULTATION AND OTHER MODES OF PHYSICAL DIAGNOSIS, IN DISEASES OF THE LUNGS AND HEART. Second American, from the second London edition, 1 vol. royal 12mo., ex. cloth, pp. 304. SI 00. HAMILTON (FRANK H.), M. D., Professor of Surgery, in Buffalo Medical College, &c. A TREATISE ON FRACTURES AND DISLOCATIONS. octavo volume, with numerous illustrations. (Preparing.) In one handsome AND SCIENTIFIC PUBLICATIONS. 17 HOBLYN (RICHARD D.), M. D. A DICTIONARY OF THE TERMS USED IN MEDICINE AND THE COLLATERAL SCIENCES. By Richard D. Hoblyn, A. M., &c A new American from the last London edition. Revised, with numerous Additions, by Isaac Hays, M. D., editor of the "American Journal of the Medical Sciences." In one large royal 12mo. volume, leather, of over 500 double columned pages. (Just Issued, 1856.) $1 50. If the frequency with which we have referred to tills volume since its reception from the publisher, *#o or three weeks ago, be any criterion for the future, the binding will soon have to be renewed, even with careful handling. We find that Dr. Hays has done the profession great service by his careful and industrious labors. The Dictionary has thus become eminently suited to our medical brethren in this country. The additions by Dr. Hays are in brackets, and we believe there is not a single page but bears (these insignia; in every instance which we have thus far noticed, the additions are really needed and ex- eeedingly valuable. We heartily commend the work to all who wish to be au courant in medical termi- nology.—Boston Med. and Surg. Journal. To both practitioner and student, we recommend this dictionary as being convenient in Bize, accurate in definition, and sufficiently full and complete for ordinary consultation.—Charleston Med. Journ. and Review. Admirably calculated to meet the wants of the practitioner or student, who has neither the means nor desire to procure a larger work. — American Lancet. Hoblyn has always been a favorite dictionary, and in its present enlarged and improved form will give greater satisfaction than ever. The American editoi, Dr. Hays, has made many very valuable additions. —N.J. Med. Reporter. To supply the want of the medical reader arising from this cause, we know of no dictionary better arranged and adapted than the one bearing the above title. It is not encumbered with the obsolete terms of a bygone age, but it contains all that are now in use ; embracing every department of medical scienoe down to the very latest date. The volume is of a convenient size to be used by the medical student, and yet large enough to make a respectable appeai- ance in the library of a physician.—Western Lancet. Hobly n's Dictionary has long been a favorite with us. It is the best book of definitions we have, and ought always to be upon the student's table.— Southern Med. and Surg. Journal. HOLLAND (SIR HENRY), BART., M.D..F. R. S., Physician in Ordinary to the Queen of England, &c. MEDICAL NOTES AND REFLECTIONS. From the third London edition. In one handsome octavo volume, extra cloth. (Now Ready.) $3 00. As the work of a thoughtful and observant physician, embodying the results of forty years' ac- tive professional experience, on topics of the highest interest, this volume is commended to the American practitioner as well worthy his attention. Few will rise from its perusal without feel- ing their convictions strengthened, and armed with new weapons for the daily struggle with disease. HUNTER (JOHN). TREATISE ON THE VENEREAL DISEASE. With copious Additions, by Dr. Ph. Ricord, Surgeon to the Venereal Hospital of Paris. Edited, with additional Notes, by F. J. Bumstead, M. D. In one octavo volume, with plates. $3 25. "EF"* See Ricord. Also, HUNTER'S COMPLETE WORKS, with Memoir, Notes, &c. &c. In four neat octavo volute jS, leather, with plates. $10 OP. HORNER (WILLIAM E.), M. D.. Professor of Anatomy in the University of Pennsylvania. SPECIAL ANATOMY AND HISTOLOGY. Eighth edition. Extensively revised and modified. In two large octavo volumes, extra cloth, of more than one thousand pages, handsomely printed, with over three hundred illustrations. $6 00. This edition enjoyed a thorough and laborious revision on the part of the author shortly before his death with the view of bringing it fully up to the existing state of knowledge on the subject of general and special anatomy. To adapt it more perfectly to the wants of the student, he introduced a large number of additional wood-engravings, illustrative of the objects described, while the pub- lishers have endeavored to render the mechanical execution of the work worthy of its extended reputation. JONES (T. WHARTON), F. R. S., Professor of Ophthalmic Medicine and Surgery in University College, London, &c. THE PRINCIPLES AND PRACTICE OF OPHTHALMIC MEDICINE AND SURGERY With one hundred and ten illustrations. Second American from the second and revised London edition, with additions by Edward Hartshorne, M. D., Surgeon to Wills' Hospital, &c. In one large, handsome royal 12mo. volume, extra cloth, of 500 pages. (Now Ready.) $1 50. We are confident that the reader will find, on ly wrought up, and digested m the author's mind, «JnfLi tto/ the execution of the work amply fulfils as to come forth with the freshness and impressive- perusal, that *hfe "e£uX°e°Vnd sustains, in every ness of an original production. We entertain little * • PTii-dvliiri.reputation of the author as doubt that thfs book will become what its author point, the already h,g* "Pu»«° ag phygioiORist hoped it might become, a manual for daily reference ^°Piwt ThebooH evidently the result and consultation by the student and the general prao- sgjd Path^'^^^eBearch, and has been written titioner. The work is marked by that correctness, Itrrlie Neatest care andAttention; it possesses clearness, and precision of style which distinguish tltK t 5f,»mS which ageneral work, like a sys- all the productions of the learned author.-£rm»A gn^manua M^NK : the.qua.ity of havfng and For. Med. Review. af Hhe materials whencesoever derived, so thorough- 18 t BLANCHARD & LEA'S MEDICAL JONES (C. HANDFIELD), F. R. S., & EDWARD H. SIEVEKING, M.D., Assistant Physicians and Lecturers in St. Mary's Hospital, London. A MANUAL OF PATHOLOGICAL ANATOMY. First American Edition, Revised. With three hundred and ninety-seven handsome wood engravings. In one large and beautiful octavo volume of nearly 750 pages, leather. (Lately Issued.) $3 75. Asa concise text-book, containing, in a condensed form, a complete outline of what is known in the domain of Pathological Anatomy, it is perhaps the best work in the English language. Its great merit consists in its completeness and brevity, and in this respect it supplies a great desideratum in our lite- rature. Heretofore the student of pathology was obliged toglean from a great number of monographs, and the field was so extensive that but few cultivated it with any degree of success. As a simple work of reference, therefore, it is of great value to the present condition of pathological anatomy. In this they have been completely successful. The work ia one of the best compilations which we have evei perused.—Charleston Medical Journal and Review. We urge upon our readers and the profession gene- rally the importance of informing themselves in re- gard to modern views of pathology, and recommend to them to procure the work before us as the bea means of obtaining this information.—Stethoscope. From the casual examination we have given we are inclined to regard it as a text-book, plain, ra- _...,1~~. c _ .u i i " it .it ' l|c liiuum-u iu icuaiu ib no u lcai-uwuk, plain, ra- !«,t nh5.Kfi- . T'i anat"m5:> and should be ln tional, and intelligible, such a book as the practical every physician's library—Western Lancet. i man ,*eet|g for dally reference. For thiB reason it In offering the above titled work to the public, the will be likely to be largely useful, as it suits itself authors have not attempted to intrude new views on to those busy men who have little time for minute their professional brethren, t.ut simply to lay before ; investigation, and prefer a summary to an elaborate them, what has long been wanted, an outline of the | tieatise.—Buffalo Medical Journal. KIRKES (WILLIAM SENHOUSE), M. D., Demonstrator of Morbid Anatomy at St. Bartholomew's Hospital, Ac. A MANUAL OF PHYSIOLOGY. A now American, from the third and improved London edition. With two hundred illustrations. In one large and handsome royal 12mo. volume, leather, pp. 580. $2 00. (Now Ready, 1857.) In again passing this work through his hands the author has endeavored to render it a correct exposition of the present condition of the science, making such alterations and additions as have been dictated by further experience, or as the progress of investigation has rendered desirable. In every point of mechanical execution the publishers have sought to make it superior to former edi- tions, and at the very low price at which it is offered, it will be found one of the handsomest and cheapest volumes before the profession. In making these improvements, care has been exercised not unduly to inerease its size, thus maintaining its distinctive characteristic of presenting within a moderate compass a clear and con- nected view of its subjects, sufficient for the wants of the student. One of the very best handbooks of Physiology we possess—presenting just such an outline of the sci- ence, comprising an account of its leading facts and generally admitted principles, as the student requires during his attendance upon a course of lectures, or for reference/whilst preparing for examination.— Am. Medical Journal. This is a new and very much improved edition of Dr. Kirkes' well-known Handbook of Physiology. Originally constructed on the basis of the admirable treatise of Miller, it has in successive editions de- veloped itself into an almost original work, though no change has been made in the plan or arrangement. It combines conciseness with completeness, and is, therefore, admirably adapted for consultation by the busy practitioner.—Dublin Quarterly Journal, Feb. 1857. Its excellence is in its compactness, its clearness, and its carefully cited authorities. It is the most convenient of text-books. These gentlemen, Messrs Kirkes and Paget, have really an immense talent for silence, which is not so common or so cheap as prat- ing people fancy. They have the gift of telling us what we want to know, without thinking it neces- sary to tell us all they know.—Boston Med and Surg. Journal, May 14, 1857. We need only say, that, without entering into dis- cussions of unsettled questions, it contains all the recent improvements in this department of medical science. For the student beginning this study, and the practitioner who has but leisure to refresh his memory, this book is invaluable, as it contains all that it is important to know, without special details, which are read with interest only by those who would make a specialty, or desire to possess a criti- cal knowledge of the subject.—Charleston Medical Journal. KNAPP'S TECHNOLOGY ; or, Chemistry applied to the Arts and to Manufactures. Kdited, with numerous Notes and Additions, by Dr. Edmund Ronalds and Dr. Thomas Richardson. First American edition, with Notes and Additions, by Prof. Walter R. Johnson. In two handsome octavo volumes, extra cloth, with about 500 wood- engravings. 86 00. LALLEMAND ON SPERMATORRHEA. Trans- lated and edited by Henry J. McDougal. ln one volume, octavo, extra cloth, 320 pages. Second American edition. $1 75. LUDLOW (J. L.), M. D. A MANUAL OF EXAMINATIONS upon Anatomy, Physiology, Surgery, Practice of Medicine, Obstetrics, Materia Medica, Chemistry, Pharmacy, and Therapeutics. Tb which is added a Medical Formulary. Designed for Students of Medicine throughout the United States. Third edition, thoroughly revised and greatly extended and enlarged. With three hundred and seventy illustrations. In one large and handsome royal 12mo. volume, leather, of over 800 closely printed pages (Now Ready.) $2 50. The great popularity of this volume, and the numerous demands for it during the two years in wnich it has been out of print, have induced the author in its revision to spare no pains to render it a correct and accurate digest of the most recent condition of all ihe branches of medical science. In many respects it may, therefore, be regarded rather as a new book than a new edition, an entice section on Physiology having been added, as also one on Osranic Chemistry, and many portions having been rewritten. A very complete series of illustrations has been introduced, and every care has been taken in the mechanical execution to render it a convenient and satisfactory book fin- study or reference. The arrangement of the volume in the form of question and answer renders it especially suited for the office examination of students and for those preparing for graduation. We know of no better companion for the stadent during the hours spent in the lecture room, or to re- fre#h^ at a glance, his memory of the various topics crammed into his head by the various professors to whom he is compelled listen.—Western Lancet, May, 1857. AND SCIENTIFIC PUBLICATIONS. 19 LEHMANN (C. G.) PHYSIOLOGICAL CHEMISTRY. Translated from the second edition by George E. Day, M. D., F. R. S., &c, edited by R. E. Rogers, M. D., Professor of Chemistry in the Medical Department of the University of Pennsylvania, wilh illustrations selected from Funke's Atlas of Physiological Chemistry, and an Appendix of plates. Complete in two large and handsome octavo volumes, extra cloth, containing 1200 pages, with nearly two hundred illus- trations. (Just Issued.) $6 00. This great work, universally acknowledged as the most complete and authoritative exposition of the principles and details of Zoochemistry, in its passage through the press, has received from Professor Rogers such care as was necessary to present it in a correct and reliable form- To such a work additions were deemed superfluous, but several years having elapsed between the appear- ance in Germany of the first and last volume, the latter contained a supplement, embodying nume- rous corrections and additions resulting from the advance of the science. These have all been incor- porated in the text in their appropriate places, while the subjects have been still further elucidated by the insertion of illustrations from the Atlas of Dr. OttoFunke. With the view of supplying the student with the means of convenient comparison, a large number of wood-cuts, from works on kindred subjects, have also been added in the form of an Appendix of Plates. The work is, therefore, pre- sented as in every way worthy the attention of all who desire to be familiar wilh the modern facts and doctrines of Physiological Science. The most important contribution as yet made to Physiological Chemistry__Am. Journal Med. Sci- ences, Jan. 1856. The present volumes belong to the small class of medical literature which comprises elaborate works of the highest order of merit.—Montreal Med. Chron- icle, Jan. 1856. The work of Lehmann stands unrivalled as the most comprehensive book of reference and informa- tion extant on every branch of the subject on which it treats.—Edinburgh Monthly Journal of Medical Science. Already well known and appreciated by the scien- tific world, Professor Lehmann's great work re- quires no laudatory sentences, as, under a new garb, it is now presented to us. The little space at our command would ill suffice to set forth even a small portion of its excellences.—Boston Med. and Surg. Journal, Dec. 1855. by the same author. (Just Issued, 1856.) MANUAL OF CHEMICAL PHYSIOLOGY. Translated from the German, with Notes and Additions, by J. Cheston Morris, M. D., with an Introductory Essay on Vital Force, by Samuel, Jackson, M. D., Professor of the Institutes of Medicine in the University of Pennsylvania. With illustrations on wood. In one very handsome octavo volume, extra c.'oth, of 336 pages. $2 25. From Prof. Jackson's Introductory Essay. In adopting the handbook of Dr. Lehmann as a manual of Organic Chemistry for the use of the stntients of the University, and in recommending his original work of Physiological Chemistry for their more mature studies, the high value of his researches, and the great weight of his autho- rity in that important department of medical science are fully recognized. The present volume will be a very convenient one I densed form, the positive facts of Physiological for students, as offering a brief epitome of the more Chemistry.—Am. Journal Med. Sciences, April, 1856. elaborate work, and as containing, in a very con- | LAWRENCE (W.), F. R. S., &c. A TREATISE ON DISEASES OF THE EYE. A new edition, edited, with numerous additions, and 243 illustrations, by Isaac Hays, M. D., Surgeon to Will's Hospi- tal, &c. In one very large and handsome octavo volume, of 950 pages, strongly bound in leather with raised bands. $5 00. This work is so universally recognized as the standard authority on the subject, that the pub- lishers in presenting this new edition hate only to remark that in its preparation the editor has carefully revised every portion, introducing additions and illustrations wherever the advance of science has rendered them necessary or desirable, constituting it a complete and thorough exponent of the most advanced state of the subject. octavo pages—has enabled both author and editor to do justice to all the details of this subject, and con- dense in this single volume the present state of our This admirable treatise—the safest guide and most comprehensive work of reference, which is within the reach of the profession.—Stethostope. This standard text-book on the department of whieh it treats, has not been superseded, by any or all of the numerous publications on the subject heretofore issued. Nor with the multiplied improve- ments of Dr. Hays, the American editor, is it at all likely that this great work will cease to merit the confidence and preference of students or practition- ers. Its ample extent—nearly one thousand large knowledge of the whole science in this department, whereby its practical value cannot be excelled. We heartily commend it, especially as a book of refer- ence, indispensable in every medical library. The additions of the American editor very greatly en- hance the value of the work, exhibiting the learning and experience of Dr. Hays, in the light in which he ought to be held, as a standard authority on all sub- jects appertaining to this specialty .—N. Y. Med. Gax. LARDNER (DIONYSIUS), D. C. L., &c. HANDBOOKS OF NATURAL PHILOSOPHY AND ASTRONOMY. Revised with numerous Additions, by the American editor. First Course, containing Media- te* Hvdrostatics, Hydraulics, Pneumatics, Sound, and Optics. In one large royal 12mo. volume of 750 pages, with 424 wood-cuts. $1 75. Second Course, containing Heat, Electricity, Mae-neti*m and Galvanism, one volume, large royal 12mo., of 450 pages, with 250 illustrations. «i 9;,. Yn.m wrnNDARY; comprising the Treatment of Constitutional and Confirmed Syphi- MARY A™ b j g„,Ce8Sful method. With numerous Cases, Formulae, and Clinical Observa- lis, by a^1® ^he .jhird and entirely rewritten London edition. In one neat octavo volume, tions. From ^ --- , _- extra cloth, of 316 pages, f 1 75. 26 BLANCHARD* & LEA'S MEDICAL PARRISH (EDWARD), Lecturer on Practical Pharmacy and Materia Medica in the Pennsylvania Academy of Medicine, Ac AN INTRODUCTION TO PRACTICAL PHARMACY. Designed as a Text- Book for the Student, and as a Guide for the Physician and Pharmaceutist. With many For- mulae and Prescriptions. In one handsome octavo volume, extra cloth, of 550 pages, wilh 243 Illustrations. $2 75. A careful examination of this work enables us to Bpeak of it in the highest terms, as being the best treatise on practical pharmacy with which we are acquainted, and an invaluable vade-mecum, not only to the apothecary and to those practitioners who are accustomed to prepare their own medicines, but to every medical man and medical student. Through- out the work are interspersed valuable tables, useful formulae, and practical hints, and the whole is illus- trated by a large number of excellent wood-engrav- ings.—Boston Med. and Surg. Journal. This is altogether one of the most useful books we have seen. It is just what we have long felt to be needed by apothecaries, students, and practitioners of medicine, most of whom in this country have to put up their own prescriptions. It bears, upon every page, the impress of practical knowledge, conveyed in a plain common sense manner, and adapted to the comprehension of all. who may read it. No detail has been omitted, however trivial it may seem, al- though really important to the dispenser of medicine. —•Southern Med. and Surg. Journal. To both the country practitioner and the city apo- thecary this work of Mr. Parrish is a godsend. A careful study of its contents will give the young graduate a familiarity with the value and mode of administering his presetlptions, which will be of as much use to his patient as to himself.— Va. Med. Journal. Mr. Parrish has rendered a veTy acceptable service Medica; it familiarizes him with the compounding of drugs, and supplies those minutiae which but few practitioners con impart. The junior practitioner will, also, find this volume replete with instruction. —Charleston Med. Journal and Review, Mar. UJ56. There is no useful information in the details of the apothecary's or country physician's office conducted according to science that is omitted. The young physician will find it an encyclopedia of indispensa- ble medical knowledge, from the purchase of a spa- tula to the compounding of the most learned pre- scriptions. The woikisby theablest pharmaceutist in the United States, and mast meet with an im- mense sale.—Nashville Journal of Medicine, April, 1856. We are glad to receive this excellent work. It will supply a want long felt by the profession, and especially by the itudent of Pharmacy. A large majority of physicians are obliged to compound their own medicines, and to them n work of this kind is indispensable.—N. O. Medical and Surgical Journal. We cannot say but that this volume is one of the most welcome snd appropriate which has for a long time been issued from the press. It is a work which we doubt not will at once secure an extensive cir- culation, as it is designed not only for the druggist and pharmaceutist, but also for the great body of practitioners throughout the country, who not only have to prescribe medicines, but in the majority of to the practitioner and student, by furnishing this instances have to rely upon their own resources— book, which contains the leading facts and principles whatever these may be—not only to compound, but of the science of Pharmacy, conveniently arranged also to manufacture the remedies they are called for study, and with special reference to those features of the subject which possess an especial practical in- terest to the physician. It furnishes the student, at the commencement of his studies, with that infor- mation which is of the greatest importance in ini- tiating him into the domain of Chemistry and Materia upon to administer. The author has not mistaken the idea in writing this volume, as it is alike useful and invaluable to those engaged in the active pui- suits of the profession, and to those preparing to en- ter upon the field of professional labors.—American Lancet, March 24, 1856. RICORD (P.), M. D., A TREATISE ON THE VENEREAL DISEAS K. By John Hunter, F. R. S. With copious Additions, by Ph. Ricord, M. D. Edited, with Notes, by Freeman J. Bumstead, M. D. In one handsome octavo volume, extra cloth, of 520 pages, with plates. $3 25. secretaries, sometimes accredited and sometimes not. Every one will recognize the attractiveness and value which this work derives from thus presenting the opinions of these two masters side by side. But, it must be admitted, what has made the foriune of the book, is the fact that it contains the -'most com- plete embodiment of the veritable doctrines of the Hdpital du Midi," which has ever been made public. The doctrinal ideas of M. Ricord, ideas which, if not universally adopted, are incontestably dominant, have heretofore only been interpreted by more or less skilful In the notes to Hunter, the master substitutes him- selfforhis interpreters, and gives his original thoughts to the world in a lucid and perfectly intelligible man- ner. In conclusion we can say that this is incon- testably the best treatise on syphilis with which we are acquainted, and, as we do not often employ the phrase, we may be excused for expressing the hope that it may find a place in the library of every phy- sician.— Virginia Med. and Surg. Journal. BY THE SAME AUTHOR ILLUSTRATIONS OF SYPHILITIC DISEASE. Translated by Thomas F. Betton, M. D. With fifty large quarto colored plates. In one large quarto volume, extra cloth. $15 00. LETTERS ON SYPHILIS, addressed to the Chiet Editor of the Union Medicale. Translated by W. P. Lattimore, M. D. In one neat octavo vol- ume, of 270 pages, extra cloth. 92 00. RIGBY (EDWARD), M. D., Senior Physician to the General Lying-in Hospital, Ac. A SYSTEM OF MIDWIFERY. With Notes and Additional Illustrations. Second American Edition. One volume octavo, extra cloth, 422 pages. $2 50. by the same author. (Now Ready, 1857.) ON THE CONSTITUTIONAL TREATMENT OF FEMALE DISEASES. In one neat royal 12mo. volume, extra cloth, of about 250 pages, f 1 00. The aim of the author has been throughout to present sound practical views of the important subjects under consideration ; and without entering into theoretical disputations and disquisitions to embody the results of his long and extended experience in such a condensed form as would ba easily accessible to the practitioner. ROYLE'S MATERIA MEDICA AND THERAPEUTICS; including the Preparations of the Pharmacopoeias of London, Edinburgh, Dublin, and of the United States. With many new medicines. Edited by Joseph Carson, M. D. With ninety-eight illustrations. In one large octavo volume, extra clotb, «f about 7.00 pages. f3 00. AND SCIENTIFIC PUBLICATIONS. 27 RAMSBOTHAM (FRANCIS H.), M.D. THE PRINCIPLES AND PRACTICE OF OBSTETRIC MEDICINE AND SURGERY, in reference to the Process of Parturition. A new and enlarged edition, thoroughly revised by the Author. With Additions by W. V. Keating, M. D. In one large and handsome imperial octavo volume, of 650 pages, strongly bound in leather, with raised bands; with sixty- four beautiful Plates, and numerous Wood-cuts in the text, containing in all nearly two hundred large and beautiful figures. (Lately Issued, 1856.) $5 00. In calling the attention of the profession to the new edition of this standard work, the publishers would remark that no efforts have been spared to secure for it a continuance and extension of the remarkable favor with which it has been received. The last London issue, which was considera- bly enlarged, has received a further revision from the author, especially for this country. Its pas- sage through the press here has been supervised by Dr. Keating, who has made numerous addi- tions with a view of presenting more fully whatever was necessary to adapt it thoroughly to American modes of practice. In its mechanical execution, n like superiority over former editions will be found. From Prof. Hodge, of the University of Pa. To the American public, it is most valuable, from its intrinsic undoubted excellence, and as being the best authorized exponent of British Midwifery. Its circulation will, I trust, be extensive throughout our country. The publishers have shown their appreciation of the merits of this work and secured its success by the truly elegant style in which they have brought it out, excelling themselves in its production, espe- cially in its plates. It is dedicated to Prof. Meigs, and has the emphatic endorsement of Prof. Hodge, as the best exponent of British Midwifery. We know of no text-book which deserves in all respects to he more highly recommended to students, and we could wish to see it in the hands of every practitioner, for they will find it invaluable for reference.—Med. Gazette. cine and Surgery to our library, and confidently recommend it to our readers, with the assurance that it will not disappoint their most sanguine ex- pectations.— Western Lancet. It is unnecessary to say anything in regard to the utility of this work. It is already appreciated in our country for the value of the matter, the clearness of its style, and the fulness of its illustrations. To the physician's library it is indispensable, while to the student as a text-book, from which to extract the material for laying the foundation of an education on obstetrical science, it has no superior.—Ohio Med. But once in a long time some brilliant genius rearB and Surg. Journal. bis head above the horizon of science, and illumi Dates and purifies every department that he investi- gates; and his works become types, by which innu- merable imitators model their feeble productions. Such a genius we find in the younger Rainsbotham, and such a type we find in the work now before us. The binding, paper, type, the engravings and wood- cuts are all so excellent as to make this book one of We will only add that the student will learn from it all he need to know, and the practitioner will find it, as a book of reference, surpassed by none other.— Stethoscope. The character and merits of Dr. Ramsbotham's work are so well known and thoroughly established, that comment is unnecessary and praise superfluous. the finest specimens of the art of printing that have : The illustrations, which are numerous and accurate, given such a world-wide reputation to its enter- are executed in the highest style of art. We cannot prising and liberal publishers. We welcome Rams- | too highly recommend the work to our readers.__St. botham's Principles und Practice of Obstetric Medi- i Louis Med. and Surg. Journal. ROKITANSKY (CARL), M.D., Curator of the Imperial Pathological Museum, and Professor at the University of Vienna, &c. A MANUAL OF PATHOLOGICAL ANATOMY. Four volumes, octavo, bound in two, extra cloth, of about 1200 pages. Translated by W. E. Swaine, Edward Sieve- king, C. H. Moore, and G. E. Day. (Just Issued.) $5 50 To render this large and important work more easy of reference, and at the same time less cum- brous and costly, the four volumes have been arranged in two, retaining, however, the separate paging, &c. The publishers feel much pleasure in presenting to the profession of the United States the great work of Prof. Rokitansky, which is universally referred to as the standard of authority by the pa- thologists of all nations. Under the auspices of the Sydenham Society of London, the combined labor of four translators has at length overcome the almost insuperable difficulties which have so long prevented the appearance of the work in an English dress. To a work so widely known, eulogy is unnecessary, and the publishers would merely state that it is said to contain the results of not less than thiety thousand post-mortem examinations made by the author, diligently com- pared, generalized, and wrought into one complete and harmonious system. The profession is too well acquainted with the re- putation of Rokitansky's work to need our assur- ance that this is one of the most profound, thorough. and valuable books ever issued from the medical press. It is sui generis, and has no standard of com- parison. It is only necessary to announce that it is issued in a form as cheap as is compatible with its size and preservation, and its sale follows as a matter of course. No library can be called com- plete without it—Buffalo Med. Journal. An attempt to give our readers any adequate idea of the vast amount of instruction accumulated in these volumes, would be feeble and hopeless. The effort of the distinguished author to concentrate in a small space his great fund of knowledge, has so charged his text with valuable truths, that any attempt of a reviewer to epitomize is at once para- lyzed, and must end in a failure.—Western Lancet. As this is the highest source of knowledge upon the important subject of which it treats, no real student can afford to be without it. The American publishers have entitled themselves to the thanks of the profession of their country, for this timeous and beautiful edition.—Nashville Journal of Medicine. As a book of reference, therefore, this work must prove of inestimable value, and we cannot too highly recommend it to the profession.—Charleston Med. Journal and Review, Jan. 1856. This book is a necessity to every practitioner.— Am. Med. Monthly. SCHOEDLER (FRIEDRICH), PH.D., Professor of the Natural Sciences at Worms, Ac. THE BOOK OF NATURE; an Elementary Introduction to the Sciences of Phvsics Astronomy, Chemistry, Mineralogy, Geology, Botany, Zoology, and Physiology. First American edition, with a Glossary and other Additions and Improvements; from the second Fnjrlish edition Translated from the sixth German edition, by Henry Mkdlock, F. C. S., &c. La one volume, small octavo, extra cloth, pp. 692, with 679 illustrations. $1 80. 28 BLANCHARD & LEA'S MEDICAL SMITH (HENRY H.), M.D., Professor of Surgery in the University of Pennsylvania, Ac. MINOR SURGERY; or, Hints on the Every-day Duties of the Surgeon. Illus- trated by two hundred and forty-seven illustrations. Third and enlarged edition. In one hand- some royal 12mo. volume, pp. 456. In leather, $2 25; extra cloth, $2 00. And a capital little book it is. . . Minor Surgery, i A work such as the present is therefore highly we repeat, is really Major Surgery, and anything I useful to the student, and we commend this one which teaches it is worth having. So we cordially to their attention.—American Journal of Medical recommend this little book of Dr. Smith's.—Med.- C-hir. Review. This beautiful little work has been compiled with a view to the wants of the profession in the matter of bandaging, Ac, and well and ably has the author performed his labors. Well adapted to give the requisite information on the subjects of which it treats.—Medical Examiner. The directions are plain, and illustrated through- out with clear engravings.—London Lancet. One of the best works they can consult on the Btibject of which it treats.—Southern Journal of Medicine and Pharmacy. Sciences. No operator, however eminent, need hesitate to consult this unpretending yet excellent book. Those who are young in the business would find Dr. Smith's treatise a necessary companion, after once under- standing its true character.—Boston Med. and Surg. Journal. No young practitioner should be without this little volume; and we venture to ussert, that it may be consulted by the senior members of the profession with more real benefit, than the more voluminous works.—Western Lancet. BY THE SAME AUTHOR, AND HORNER (WILLIAM E.), M. D., • Late Professor of Anatomy in the University of Pennsylvania. AN ANATOMICAL ATLAS, illustrative of the Structure of the Human Body. In one volume, large imperial octavo, extra cloth, with about six hundred and fifty beautiful figures. $.3 00. late the student upon the completion of this Atlas, as it is the most convenient work of the kind that has yet appeared ; and we must add, the very beau- tiful manner in which it is "got up" is so creditable to the country as to be flattering to our national pride.—American Medical Journal. These figures are well selected, and present a complete and accurate representation of that won- derful fabric, the human body. The plan of this Atlas, which renders it so peculiarly convenient for the student, and its superb artistical execution, have been already pointed out. We must congratu- SARGENT (F. W.), M. D. ON BANDAGING AND OTHER OPERATIONS OF MINOR SURGERY. Second edition, enlarged. One handsome royal 12mo. vol., of nearly 400 pages, with 182 wood- cuts. Extra cloth, $1 40; leather, $1 50. This very useful little work has long been a favor- ite with practitioners and students. The recent call for a new edition has induced its author to make numerous important additions. A slight alteration in the size of the page has enabled him to introduce the new matter, to the extent of some fifty pages of the former edition, at the same time that his volume is rendered still more compact than its less compre- hensive predecessor. A double gain in thus effected. which, in a vade-mecum of this kind, is a material improvement.—Am. Medical Journal. Sargent's Minor Surgery has always been popular, and deservedly so. It furnishes that knowledge of the most frequently requisite performances of surgical art which cannot be entirely understood by attend- ing clinical lectures. The art of bandaging, which is regularly taught in Europe, is very frequently overlooked by teachers in this country ; the student Bad junior practitioner, therefore, may often require that knowledge which this little volume so tersely and happily supplies. It is neatly printed and copi- ously illustrated by the enterprising publishers, and should be possessed by all who desire to be thorough- ly conversant with the details of this branch of our art.—Charleston Med. Journ. and Review, March, 1856. A work that has been so long and favorably known to the profession as Dr. Sargent's Minor Surgery, needs no commendation from us. We would remark, however, in this connection, that minor surgery sel- dom gets that attention in our schools that its im- portance deserves. Our larger works are also very defective in their teaching on these small practical points. This little book will supply the void which all must feel who have not studied its pages.—West- ern Lancet, March, 1856. We confess our indebtedness to this little volume on many occasions, and can warmly recommend it to our readers, as it is not above the consideration of the oldest and most experienced.—American Lan- cet, March, 1856. SKEY'S OPERATIVE SURGERY. In one very handsome octavo volume, extra cloth, of over 650 pages, with about one hundred wood-cuts. $3 25. STAN LEY'S TREATISE ON DISEASES OF THE BO.N'ES. In one volume, octavo, extra cloth, 286 page* $1 50. SOLLY ON THE HUMAN BRAIN; its Structure, Physiology, and Diseases. From the Second and much enlarged London edition. In one octavo volume, extra cloth, of 500 pages, with 120 wood- cuts. $2 00. SIMON'S GENERAL PATHOLOGY, as condne- ive to the Establishment of Rational Principles for the prevention and Cure of Disease. In one neat octavo volume, extra cloth, of 212 pages. 81 25. STILLE (ALFRED), M.D. PRINCIPLES OF GENERAL AND SPECIAL THERAPEUTICS ln handsome octavo. (Preparing.) SIBSON BSON (FRANCIS), M. D., Physician to St. Mary's Hospital. MEDICAL ANATOMY. Illustrating the Form, Structure, and Position of the Internal Organs in Health and Disease. In large imperial quarto, with splendid colored plates. To match "Maclise's Surgical Anatomy." Part I. (Preparing.) AND SCIENTIFIC PUBLICATIONS. 29 SHARPEY (WILLIAM), M. D., JONES QUAIN, M. D., AND RICHARD QUAIN, F. R. S., &c. HUMAN ANATOMY. Revised, with Notes and Additions, by Joseph Leidy, M. D., Professor of Anatomy in the University of Pennsylvania. Complete in two large octavo volumes, leather, of about thirteen hundred pages. Beautifully illustrated with over five hundred engravings on wood. $6 00. It is indeed a work calculated to make an era in anatomical study, by placing before the student every department of his science, with a view to the relative importance of each; and so skilfully have the different parts been interwoven, that no one who makes this work the basis of his studies, will hereafter have any excuse for neglecting or undervaluing any important particulars connected with the structure of the human frame; and whether the bias of his mind lead him in a more especial manner to surgery, physic, or physiology, he will find here a work at once so comprehensive and practical as to defend him from exclusiveness on the one hand, and pedantry on the other.__ Journal and Retrospect of the Medical Sciences. We have no hesitation in recommending this trea- tise on anatomy as the most complete on that sub- ject in the English language; and the only one, perhaps, in any language, which brings the state of knowledge forward to the most recent disco- veries.—The Edinburgh Med. and Surg. Journal. SMITH (W. TYLER), M. D., Physician Accoucheur to St. Mary's Hospital, &c. ON PARTURITION, AND THE PRINCIPLES AND PRACTICE OF OBSTETRICS. In one royal 12mo. volume, extra cloth, of 400 pages. $125. BY THE SAME AUTHOR. A PRACTICAL TREATISE ON THE PATHOLOGY AND TREATMENT OF LEUCORltHCEA. With numerous illustrations. In one very handsome octavo volume, extra cloth, of about 250 pages. $1 50. We hail the appearance of this practical and invaluable work, therefore, as a real acquisition to our medical literature.—Medical Gazette. TAYLOR (ALFRED S.), M. D., F. R. S., Lecturer on Medical Jurisprudence and Chemistry in Guy's Hospital. MEDICAL JURISPRUDENCE. Fourth American, from the fifth improved and enlarged English Edition. With Notes and References to American Decisions, by Edward Hartshorne, M. D. In one large octavo volume, leather, of over seven hundred pages. (Just Issued, 1856.) $3 00. This standard work has lately received a very thorough revision at the hands of the author, who has introduced whatever was necessary to render it complete and satisfactory in carrying out the objects in view. The editor has likewise used every exertion to make it equally thorough with regard to all matters relating to the practice of this country. In doing this, he has carefully ex- amined all that has appeared on the subject since the publication of the last edition, and has incorpo- rated all the new information thus presented. The work has thus been considerably increased in size, notwithstanding which, it has been kept at its former very moderate price, and in every respect it will be found worthy of a continuance of the remarkable favor which has carried it through so many editions on both sides of the Atlantic. A few notices of the former editions are appended. We know of no work on Medical Jurisprudence which contains in the same space anything like the Bame amount of valuable matter.—N. Y. Journal of Medicine. No work upon the subject can be put into the hands of students either of law or medicine which will engage them more closely or profitably; and none could be offered to the busy practitioner of either calling, for the purpose of casual or hasty reference, that would be more likely to afford the aid desired. We therefore recommend it as the best and safest manual for daily use.—American Journal of Medical Sciences. So well is this work known to the members both of the medical and legal professions, and so highly is it appreciated by them, that it cannot be necessary for us to say a word in its commendation; its having already reached a fourth edition being the best pos- sible testimony in its favor. The author has ob- viously subjected the entire work to a very careful revision.—Brit, and Foreign Med. Chirurg. Review. This work of Dr. Taylor's is generally acknow- ledged to be one of the ablest extant on the subject of medical jurisprudence. It is certainly one of the BY THE SAME AUTHOR. ON POISONS, IN RELATION TO MEDICAL JURISPRUDENCE AND MEDICINE. Edited, with Notes and Additions, by R. E. Griffith, M. D. In one large octava volume, leather, of 688 pages. $3 00 TODD (R. B.), M. D., F. R. S., &c. CLINICAL LECTURES ON CERTAIN DISEASES OF THE URINARY ORGANS AND ON DROPSIES. In one octavo volume. (Now Ready, 1857.) $1 50 The valuable practical nature of Dr. Todd's writings have deservedly rendered them favorites with the pro'ession, and the present volume, embodying the medical aspects of a class of diseases not elsewhere to be found similarly treated, can hardly fail to supply a want long felt by the prao- most attractive books that we have met with; sup- plying so much both to interest and instruct, that we do not hesitate to affirm that after having once commenced its perusal, few could be prevailed upon to desist before completing it. In the last London edition, all the newly observed and accurately re- corded facts have been inserted, including much that is recent of Chemical, Microscopical, and Patholo- gical research, besides papers on numerous subjects never before published .-Charleston Medical Journal and Review. It is not excess of praise to say that the volume before us is the very best treatise extant on Medical Jurisprudence. In saying this, we do not wish to be understood as detracting from the merits of the excellent works of Beck, Ryan, Traill, Guy, and others; but in interest and value we think it must be conceded that Taylor is superior to anything that has preceded it. The author is already well known to the profession by his valuable treatise on Poisons; and the present volume will add materially to his high reputation for accurate and extensive know- ledge and discriminating judgment.—N. W. Medical and Surgical Journal. 30 BLANCHARD & V^A'S MEDICAL Now Complete (April, 1857.) TODD (ROBERT BENTLEY), M. D., F. R. S., Professor of Physiology in king's College, '.Vmdon; and WILLIAM BOWMAN, F. R. S., Demonstrator of Anatomy in King's College, London. THE PHYSIOLOGICAL ANATOMY AND PHYSIOLOGY OF MAN. With about three hundred large and beautiful illustrations on wood. Complete in one large octavo volume, of 950 pages, leather. Price $4 50. The very great delay which has occurred in the completion of this work has arisen from the de- sire of the authors to verify by their own examination the various questions and statements pre- sented, thus rendering the work one of peculiar value and authority. By the wideness of its scope and the accuracy of its facts it thus occupies a position of its own, and becomes necessary to all physiological students. kjr" Gentlemen who have received portions of this work, as published in the " Medical News and Library," can now complete their copies, if imrrUiate application be made. It will be fur- nished as follows, free by mail, in paper covers' (.iie'Dl"'-1*- backs. Parts I., II., III. (pp. 25 to 552), $2 50. •'••-' Part IV. (pp. 553 to end, with Title, Preface, Contents, &c), $2 00. Or, Part IV., Section II. (pp. 725 to end, wilh Title, Preface, Contents, &c), $1 25. In the present part fthird) some of the most diffi- cult subjects in Anatomy and Physiology are handled in the most masterly manner. Its authors have stated that this work was intended " for the use of the student and practitioner in medicine and sur- gery," and we can recommend it to both, confident that it is the most perfect work of its kind. We cannot conclude without strongly recommending the present work to all classes of our readers, recognis- ing talent and depth of research in every page, and believing, as we do, that the diffusion of such know- ledge will certainly tend to elevate the sciences of Medicine and Surgery.—Dublin Quarterly Journal of Medical Sciences. TANNER (T. HJ, M. D., Physician to the Hospital for Women, Ac. A MANUAL OF CLINICAL MEDICINE AND PHYSICAL DIAGNOSIS. To which is added The Code of Ethics of the American Medical Association. Second American Edition. In one neat volume, small 12mo. Price in extra cloth, 87$ cents; flexible style, lor the pocket, 80 cents. Dr. Tanner has, in a happy and successful manner, indicated the leading particulars to which, in the clinical study of a case of disease, the attention of the physician is to be directed, the value and import of the various abnormal phenomena detected, and the several instrumental and accessory means which may be called into requisition to facilitate diagnosis and increase its certainty.—Am. Journal of Med. Sciences. The work is an honor to its writer, and must ob- tain a wide circulation by its intrinsic merit alone. Suited alike to the wants of students and practi- tioners, it has only to be seen, to win for itself a place upon the shelves of every medical library. Nor will it be " shelved" long at a time ; if we mis- take not, it will be found, in the best sense of the homely but expressive word, " handy." The styl* is admirably clear, while it is so sententious as not to burden the memory. The arrangement is, to our mind, unexceptionable. The work, in short, de- serves the heartiest commendation.—Boston Med. and Surg. Journal. WATSON (THOMAS), M.D., &.c. LECTURES ON THE PRINCIPLES AND PRACTICE OF PHYSIC Third American edition, revised, with Additions, by D. Francis Condie, M. D., author of a "Treati>e on the Diseases of Children," &c. large pages, strongly bound with raised bands. To say that it is the very best work on the sub- ject now extant, is but to echo the sentiment of the medical press throughout the country. — N. O. Medical Journal. Of the text-books recently republished Watson is very justly the principal favorite.—Holmes's Rep. to Nat. Med. Assoc. By universal consent the work ranks among the very best text-books in our language.—Illinois and Indiana Med. Journal. Regarded on all hands as one of the very best, if not the very best, systematic treatise on practical medicine extant.—St. Louis Med. Journal. In one octavo volume, of nearly eleven hundred $3 25. Confessedly one of the very best works on the principles and practice of physic in the English or any other language.—Med. Examiner. Asa text-book it has no equal; as a compendium of pathology and practice no superior.—New York Annalist. We know of no work better calculated for being placed in the hands of the student, and for a text- book ; on every important point the author seems to have posted up his knowledge to the day.— Amer. Med. Journal. One of the most practically useful books that ever was presented to the student. — N. Y. Med. Journal. WHITEHEAD ON THE CAUSES AND TREAT- MENT OF ABORTION AND STERILITY. Second American Edition. In one volume, octa- vo, extra cloth, pp. 308. $1 75. WALSHE ON DISEASES OF THE HEART, LUNGS, AND APPENDAGES; their Symp- toms and Treatment, ln one handsome volume, extra cloth, large royal 12mo., 512 pages. $1 50. WHAT TO OBSERVE AT THE BEDSIDE AND AFTER DEATH, IN MEDICAL CASES. Published under the authority of the London Society for Medical Observation. A new American, from the second and revised London edition. In one very handsome volume, royal 12mo., extra cloth. $1 00. To the observer who prefers accuracy to blunders I One of the finest aids to a young practitioner we and precision to carelessness, this little book is in- have ever seen.—Peninsular Journal of Medicine. valuable.—N. H. Journal of Medicine. | AND SClKJNitr TO PUBLICATIONS. WILSON (ERASA. /S), M.D., F. R. S., Lecturer on Anatomy, London. A SYSTEM QF HUMAN ANATOMY, General and Special. Fourth Ameri- can, from the last English edition. Edited by Paul B. Goddard, A. M., M. D. With two hun- dred and fifty illustrations. Beautifully printed in one large octavo volume, leather, of nearly six hundred pages. $3 00. In many, if not all the Colleges of the Union, it i It offers to the student all the nssistance that can has become a standard text-book. This, of itself, be expected from such a work.—Medical Examiner. ia sufficiently expressive of its value. A work very -jo now be found a collection of Selected Formula, consisting for the most part of prescriptions of which the author has tested the value. In the present edition Mr. Wilson presents us with the results of his matured experience gained after an extensivt acquaintance with the pathology and treat- ment of cutaneous affections; and we have now be- fore us not merely a reprint of his former publica- tions, but an entirely new and rewritten volume. Thus, the whole history of the diseases affecting the skin, whether they originate in that structure or are also, just ready, A SERIES OF PLATES ILLUSTRATING WILSON ON DISEASES OF THE SKIN ; consisting of nineteen beautifully executed plates, of which twelve are exquisitely colored, presenting the Normal Anatomy and Pathology of the Skin, and containing accurate re- presentations of about one hundred varieties of disease, most of them the size of naiure. Price in cloth §4 25. In beauty of drawing and accuracy and finish of coloring these plates will be found superior to anything of the kind as yet issued in this country. The plates by which this editition is accompanied j The representations of the various forms of cutane- leave nothing to be desired, so far as excellence of ous disease are singularly accurate, and the coloring delineation and perfect accuracy of illustration are , exceeds almost anything" we have met with in point concerned.__Meaico-Chirurgical Review. of delicacy and finish.—British and Foreign Medical Of these plates it is impossible to speak too highly. | *«<***«*• BY THE SAME AUTHOR. ON CONSTITUTIONAL AND HEREDITARY SYPHILIS, AND ON SYPHILITIC ERUPTIONS. In one small octavo volume, extra cloth, beautifully printed, with four exquisite colored plates, presenting more than thirty varieties of syphilitic eruptions. $2 25. BY THE SAME AUTHOR. (Just Issued.) HEALTHY SKIN; A Popular Treatise on the Skin and Hair, their Preserva- tion and Management. Second American, from the fourth London edition. One neat volume, royal 12mo., extra cloth, of about 300 pages, with numerous illustrations. $1 00; paper cover, 75 cents. _________________ WILDE (W. R.), Surgeon to St. Mark's Ophthalmic and Aural Hospital, Dublin. AURAL SURGERY, AND THE NATURE AND TREATMENT OF DIS- EASES OF THE EAR. Ia one handsome octavo volume, extra cloth, of 476 pages, with illustrations. $2 80. Thi. work certainly contains more information on the author for his manful effort to rescue this depart .u h^ot in which it is devoted than any other ment of surgery from the hands of the empirics who wfih which we are acquainted. We feel grateful to nearly monopolize it.- Va. Med. and Surg. Journal. 82 BLANCHARD & LEA'S MEDICAL PUBLICATIONS. ■ WEST (CHARLES), M. D., Accoucheur to and Lecturer on Midwifery at St. Bartholomew's Hospital, Physician to the Hospital for Sick Children, Ac. LECTURES ON THE DISEASES OF INFANCY AND CHILDHOOD. Second American, from the Second and Enlarged London edition. In one volume, octavo, extra cloth, of nearly five hundred pages. $2 00. ligation by this able, thorough, and finished work upon a subject which almost daily taxes to the ut- most the skill of the general practitioner. He has with singular felicity threaded his way through all the tortuous labyrinths of the difficult subject he has undertaken to elucidate, and has in many of the darkest corners left a light, which will never be extinguished.—Nashville Medical Journal. We take leave of Dr. West with great respect for his attainments, a due appreciation of his acute powers of observation, and a deep sense of obliga- tion for this valuable contribution to our profes- sional literature. His book is undoubtedly in many respects the best we possess on diseases of children. Dublin Quarterly Journal of Medical Science. Dt. West has placed the profession under deep ob- ^ BY the same author. (Nearly Ready.) Publishing in the "Medical News and Library," for 1856 and 1857. LECTURES ON THE DISEASES OF WOMEN. In two parts. Part I. 8vo. of about 300 pages, comprising «*e Ureases of the Uterus. Part II. (Preparing), will contain Disease^ of the Ovaries, and of all the parts -'onnected with the Uterus; of the Bladder, Vagina, and External Organs. The ob'jet of the author in this work is to present a complete but succinct treatise on Female Diseases."embodying the results of his experience during the last ten years at St. Bartholomew'* and the Midwifery Hospitals, as well as in private practice. The characteristics which have se- cured to his former works so favorable a reception, cannot fail to render the present volume a standard authority on its important subject. To show the general scope of the work, an outline of the Contents of Part I. is subjoined. Lectures I, II— Introductory—Symptoms—Examination of Symptoms—Modes of Examina- tions. Lectures III., IV., V — Disorders of Menstruation, Amenorrhea, Menorrhagia, Dys- menorrhea. Lectures VI, VII., VIII—Inflammation of the Uterus, Hypertrophy, Acute Inflammation, Chronic Inflammation, Ulceration of the Os Uteri, Cervical Leucorrhcea. Lecture* IX., X., XL, XII, XIII.—Misplacement of the Uterus, Prolapsus, Anteversion, Retrover- sion, Inversion. Lectures XIV., XV., XVI, XVII— Uterine Tumors and Outgrowths, Mucous, Fibro-cellular, and Glandular Polypi, Mucous Cysts, Fibrinous Polypi, Fibrous Tumors, Fibrous Polypi, Fatty Tumors, Tubercular Diseases. Lectures XVIII, XIX., .XX—Canoer of the Uterus. Part II. will receive an equally extended treatment, rendering the whole an admirable text-book for the student, and a reliable work for reference by the practitioner. by the same author. (Just Issued) AN ENQUIRY INTO THE PATHOLOGICAL IMPORTANCE OF ULCER- ATION ( F THE OS UTERI. In one neat octavo volume, extra cloth. $1 CO. WILLIAMS (C. J. B.), M.D., F. R. S., Professor of Clinical Medicine in University College, London, Ac. PRINCIPLES OF MEDICINE. An Elementaiy View of the Causes, Nature, Treatment, Diagnosis, and Prognosis of Disease; with brief remarks on Hygienics, or the pre- servation of health. A new American, from the third and revised London edition, ln one octavo volume, leather, of about 500 pages. $2 50. (Now Ready, May, 1857.) The very recent and thorough revision which this work has enjoyed at the hands of the au'hor has brougt' it so completely up to the present state of the subject that in reproducing it no t.dditiona have been found necessary. The success which the work has heretofore met shows that -'s im- portance has been appreciated, and in its present form it will be found eminently worthy a continu- ance of the same favor, possessing as it does the strongest claims to the attention of the medical student and practitioner, from the admirable manner in which the various inquiries in the different branches of pathology are investigated, combined and generalized by an experienced practical phy- sician, and directly applied to the investigation and treatment of disease. We find that the deeply-interesting matter and style of this book have so far fascinated us, that we have unconsciously hung upon its pages, not too long, indeed, for our own profit, but longer than re- viewers can be permitted to indulge. We leave the further analysis to the student and practitioner. Our judgment of the work has already been sufficiently expressed. It is a judgment of almost unqualified praise. The work is not of a controversial, but of a didactic character; and as such we hail it, and recommend it for a text-book, guide, and constant companion to every practitioner and every student who wishes to extricate himself from the well-worn ruts of empiricism, and to base his practice of medi- cine upon principles.—London Lancet, Dec.27,1850. A text-book to which no other in our language is comparable.—Charleston Medical Journal. No work has ever achieved or maintained a mow deserved reputation.— Va. Med. and Surg. Journal. YOUATT (WILLIAM), V. S. THE HORSE. A new edition, with numerous illustrations; together with a general history of the Horse; a Dissertation on the American Trotting Horse; how Trained and Jockeyed; an Account of his Remarkable Performances; and an Essay on the Ass and the Muk. By J. S. Skinner, formerly Assistant Postmaster-General, and Editor of the Turf Register One large octavo volume, extra cloth, f 1 50. The attention of all who keep horses is requested to this handsome and complete edition of a work which is recognized as the standard authority on all matters connected with veterinary medi- cine. The very low price at which it is now offered, free by mail, places it within the reach of every one. by the same author. THE DOG. Edited by E. J. Lewis, M. D. With numerous and beautiful illustrations. In one very handsome volume, crown Svo., crimson cloth, gilt, f 1 25. XT .^ f YfLJ .f\\ & 4!^ /, X c=w/\ ^40 ^ ^L^ NLM032067339