i'.y,- ,■"2 •, ■ ■-• Hi''.' "jy , • ✓«<•». . * ■'■•£-&:;a:.\* \a ■•■■.■■i-.VOr^ • • — to? ***!*&' 5i> '%7 *■ .•^■v». ^ :**■ ** v :»•*. r«tt * 4 V \ ; :.?i(': -?■ k:^ - >. ■<. *■.' ■',_ 4t . -J !P*.V\, ; ' ■• '&-', ft6**'* - . - r>.,a • . ■'.all* •' * ft* LIBRARY OF THE MASS. MED. COLLEGE. ^ 7?ij/ao nitri ??/)/>vii/yyi/vwf» Boston /' Medical Library Association, 19 BOYLS'TOlsr PLACE, ']Q^ . _ _,-20 ..(C)^ FROM THE FOURTH LONDON EDITION , IMBBiUEEA ILY.-IHF, ^UTfjOlt. ________ NEW-YORK : PRINTED AND SOLD BY COLLINS AND CO. NO. 189. PEARL-STREET, 1812, TO ALEXANDER WOOD, SURGEON, WHOSE ABILITIES, AND SKILL, AND DISINTERESTED CONDUCT, HAVE RAISED HIM, BY COMMON CONSENT, TO THE FIRST RANK, IN A MOST USEFUL PROFESSION, CONDUCTING HIM, IN HONOUR, TO THAT PERIOD OF LIFE IN WHICH HE MUST FEEL, WITH PLEASURE, HOW COMPLETELY HE ENJOYS THE CONFIDENCE OF THE PUBLIC, AND THE ESTEEM OF ALL GOOD MEN, THIS BOOK OF ANATOMY IS PRESENTED BY HIS PUPIL TOHN BELL, ADVERTISEMENT To the second American Edition. JL HE first American edition of this work being en- tirely sold, and the demand still existing and increas- ing, the Publishers are again induced to present the student of Anatomy with a new edition of this justly celebrated work ; and while acknowledging their past success, they would express the obligations under which they are laid by the Medical Profession in general, and particularly by the Professors of Anatomy throughout the United States, for their patronage and encouragement. In Great Britain, during a short period of time, four editions of the work were printed and sold in succession, which circumstance sufficiently proves its merit; as no book, treating of so important a science, would ex- perience such a rapid sale unless penned by pro- fessors of the greatest eminence. A few of the numerous commendations bestowed on the work by the most respectable critics, are an- nexed ; many more might have been added, but it is presumed these are sufficient to satisfy every rea- sonable enquirer. In regard to the advantages claimed by this Ameri- can edition, the publishers believe that they have on no former occasion been more successful in accom- plishing the two important objects—typographical Vol. I. a IV correctness, and great reduction in the price of the work. With respect to the former of these advantages, the publishers can confidently claim a decided prefer- ence to the English editions. Seldom has a work been issued from the press more loaded with typo- graphical errors, many of them of serious magnitude, than the different editions of this work, which have been published in London. Partly through the aid of a very competent medical friend, who generously offered his services to assist them, the publishers have been able to correct several hundred errors of the press. The custom of some authors in Great Britain, of submitting their manuscripts, not always very legible, entirely to the care of the printer, whose distance from their own place of residence precludes the possibility of their examining the proof-sheets, is the general, though unsatisfactory apology, offered for the numerous typographical mistakes, which are to be found in many valuable works imported from England. The Publishers have the satisfaction to state that the price of this edition is reduced to less than half that of the London copy, as sold in this country. The Engravings are done by the best American Art- ists : the greater part of those executed on copper, especially in the second volume, are much superior to the original; and those on wood, introduced on the punted pages, are pronounced by competent judges, to answer the object in view better than the faint and obscure impressions of the English copy. V The artists who have produced these engravings, having both been regularly taught the Anatomy of the Human Body, may reasonably claim a reliance on their accuracy. It is scarcely necessary to remark, that scrupulous care has been taken, not to omit a syllable of the let- ter-press nor a plate, but that the work should be presented entire. It will be apparent to the Medical Profession, that in the execution of this work, the publishers have in- curred a very heavy expense. If they shall find them- selves encouraged in future, as they have been in several of their late offerings to the profession, they intend to pursue, with redoubled exertions, the busi- ness of reprinting, at greatly reduced prices, the best works of English Authors relating to the science of Medicine: and they are impressed with the hope that, besides receiving an equitable pecuniary remu- neration, they will materially subserve the interests of Medical Science in the United States. CHARACTER OF THIS WORK, By Professional Critics. " It would be injustice to confound this work with the ordinary compilations from the common stock of elementary writers, and the transcribed lectures of the class-room. It is obviously the re- sult of very extensive study, both in books, and in the dissecting- room, and its completion now supplies a want which was much felt by the English reader. The description is clear and accurate, and the engraved sketches occasionally introduced, are also very VI happily devised in assisting the reader to gain a full idea of the relative situation of important and complicated parts of anatomy. They add much to its sterling value, as a comprehensive and well- executed system." Aikin's Annual Review. 11 Anatomy, in common with every other branch of natural sci- ence, has been going on with progressive improvement ever since the arrival of letters in Europe. It therefore becomes necessary from time to time, that new systems should be formed, in which the essays of different professors who have exerted themselves in perfecting the description of particular parts of the body, or in me- liorating the whole, should be collected." After enumerating many celebrated anatomists who have improved the art, the re- viewers conclude: " Having said thus much with regard to the great men who have laboured and are labouring to improve the art which it seemed to demand, we shall readily acknowledge that the authors have collected their materials with industry, and have en- riched their work with the principal improvements in physiology, which the present age has produced." British Critic. " In our account of the former part [the first two volumes by John Bell,] we bore a willing testimony to the ingenious and inte- resting manner in which the subject was handled By judiciously blending the physiology, or doctrine of functions, with the anato- mical descriptions, by frequent occasional references to pathology and practice, and by a manner peculiarly impressive and interest- ing, he wa*s enabled to excite the attention of the student to a sub- ject of the first importance to the healing art, but one which is ren- dered dry and disgusting by the ordinary mode of treating it. The latter volumes by Mr. Charles Bell, are respectably executed; and together they form a body of anatomy, greatly superior to any at present to be found in our language.'' London Medical and Chirurgical Review. The editors of the New-York Medical Repository, thus announce the first American edition. « Our readers we are confident will universally participate the pleasyre we feel in announcing that Messrs. Collins 8c Perkins Vll have undertaken to give an American edition of the ANATOMY OF THE HUMAN BODY, by John and Charles Bell, in two large volumes, octavo, from the fourth London edition, in four volumes, octavo, corrected, and illustrated by one hundred and twenty five engravings. This grand work, embracing by far the most complete system of Anatomy and Physiology in the English language, and possessing a reputation which is extended by the approbation of every additional circle of readers, will thus be pub- lished at a price so greatly reduced as to circulate to a wide extent, be adopted as a standard authority in our Medical Seminaries, and eventually come into the hands of all practitioners of physic in the United States. We most sincerely congratulate the public on the prospect of acquiring this splendid improvement in the means of cultivating Anatomy and Physiology in every part of our country ; as we are confident that the general circulation of this work would be alone sufficient to advance, in a considerable degree, the respectability and usefulness of the Medical profession in this new world.*' The editors of the New- York Medical and Philo- sophicalJournal and Review, in announcing the same undertaking, dwell on the great importance to the profession of thus reducing the prices of imported books, and proceed as follows : " It has been objected to the editions issued from our presses, particularly those in which there are plates, that though cheaper, they are likewise inferior to those imported. This we think will not be the case with the above edition of Bell's Anatomy ; for we have seen some of the plates, which are superior to those in the London copy. The extensive sale of the book, will, we hope, re- munerate the activity and enterprize of the publishers." The editor of the Philadelphia Medical Museum, has called the attention of his readers to the same subject, and informed them, that " This highly useful and important work is to be printed in two volumes, 8vo. on a fine vellum paper, from the fourth London edi- viii tion. A selection of reviews from English publications accompa- nies the prospectus, which cannot fail of evincing the high degree of estimation in which this interesting work is held; and as it is given at less than half the price of the English edition, must en- sura the sanction of the Physicians of America, as a work in the highest degree worthy of a place in every medical library." MEDICAL BOOKS. COLLINS fc? CO. announce to the Medical Pro- fession, that they have been induced to turn their attention to the sale of MEDICAL, CHEMICAL, AND BOTANICAL BOOKS, In consequence of the solicitations of many of the most respectable of the Faculty. Whilst they respectfully solicit the further pa- tronage of the Profession at large, the advertisers should, with gratitude, acknowledge the very exten- sive encouragement which they have already receiv- ed. Their obligations are due, not only to the dif- ferent medical professors and lecturers of the two Colleges in New-York, who in their private capacity, have recommended their establishment, but also to medical institutions, which have promoted their un- dertaking, by officially constituting the advertisers their printers and medical booksellers. Their medical catalogue, which already contains more than double the number of medical books to be found in any book-store of the United States, will be constantly enlarged by the addition of every new work of merit which may appear either in Europe or IX America ; the advertisers having established a cor- respondence in England, which will insure to them this important advantage, unless political differences between the two countries may operate to defeat it. The several Medical Journals printed in Philadel- phia and Baltimore, are also regularly received for delivery to subscribers and others. With regard to charges, those for American books, must be regulated by the prices adopted by their publishers ; but foreign books are priced by the in%» porter. To those of the Faculty who have already dealt with the advertisers, it may be sufficient to ob- serve, that they pledge themselves to continue to sell on the same favourable terms as heretofore. Upon American editions, (periodical publications and a few others excepted) liberal discounts will be allowed to wholesale purchasers ; but upon imported books, such are their present reduced retail prices, only a very small discount can be afforded. Did the advertisers adopt the practice of marking imported books as much above their cost as are those of Amer- ican origin, the same large discounts could with equal propriety be allowed; but they apprehend that such a system is not cakuLted to dispense equal justice to all, nor to enable the purchaser of a siigle book to possets hin^ur of it at a price for which it can be fairly afforded. PREFAC E. ■- »»*;,* lO those who afe at all acquainted with books on anatomy, the appearance of a new one on the subject will not be sur- prising : to those who are not yet acquainted with such writ- ings, I have only to say that I have written this book, because I believed that such a one was needed, and must be useful. I have endeavoured to make itso plain and simple as to be easily understood; I have avoided the tedious interlarding of techni- cal terms (which has been too long the pride of anatomists and the disgrace of their science), so that it may read smoothly compared with the studied harshness, and, I may say, ob- scurity, of anatomical description. If an author may ever be allowed to compare his book with others, it must be in the me- chanical part ; and I may venture to say, that this book is full and correct in the anatomy, free and general in the explana- tions, not redundant, I hope, and yet not too brief. If, in the course of this volume, I shall appear to have given to theories a place and importance far higher than they really deserve, my reader will naturally feel how useful they are in preserving the due balance between what is amusing and what is useful j between the looser doctrines of functions and the close demonstration of parts. He will be sensible how much more easily these things can be read in the closet than taught in any public course ; he will, I think, be ready to Vol. I. b VI. PREFACE. acknowledge, that I introduce such theories only as should connect the whole, and maybe fairly distinguished as the phy- siology of facts; and he will perceive, that in this, too, I feel a deference for the public opinion, and that respect for the established course of education which it is natural to feel and to comply with. Thus, perhaps, it is less immodest for an author to put clown what he thinks he may honestly say concerning his own book, than to omit those apologies which custom requires ; which give assurance that he has not entered upon his task rashly, nor performed it without some labour and thought ; which are the truest signs of his respect for the Public, and of his care for that science to which he has devoted his life. With these intentions and hopes I offer this book to the Public; and more particularly to those in whose education I have a chief concern : not without a degree of satisfaction at having accomplished what, I think, cannot fail to be useful ; and surely not without an apprehension of not having done (iin this wide and difficult subject) all that may be expected or wished for. • Every book of this kind should form a part of some greater system of education : it should not only be entire in its own plan, but should be as a part of some greater whole ; without which support and connection a book of science is insulated and lost. This relation and subserviency of his own particu- lar task to some greater whole, is first in an author's mind : he ventures to look forward to its connection with the general science and common course of education ; or he turns it to a correspondence and harmony with his own notions of study : and if these notions are to give the complexion and character to any book, it should be when it is designed for those who are entering upon their studies, as yet uncertain where to begin, or how to proceed. Hardly any one has been so fortunate as to pursue the study of his own science under any regular and perfect plan ; and there are very few with whom a consciousness of this does not make a deep and serious impression at some future period, ac- PREFACE. Vli companied with severe regret for the loss of time never to be retrieved. In medicine, perhaps, more than in any other science, we begin our studies thoughtless and undecided, fol- lowing whatever is delightful (as much is delightful), and ne- glecting the more severe and useful parts : but as we advance towards that period in which we are to enter upon a most dif- ficult profession, and to take our place and station in life ; and when we think of the hesitation, anxiety, and apprehension, with which we must move through the first years of practice— we begin to look back with regret on every moment that is past; with a consciousness of some idle hours ; and (what is more afflicting still) with an unavailing sense of much ill- directed, unprofitable labour :—for there is no study upon which a young man enters with a more eager curiosity ; but not instructed in what is really useful, nor seriously impressed with the importance of his future profession, he thinks of his studies rather as the amusement, than as the business, of life ; slumbers through his more laborious and useful tasks, and soon falls off to the vain pursuit of theories and doctrines. If I were not persuaded of the important consequences, of the infinite gain or loss which must attend the first steps, in every profession, I should not feel, but, above all, I should not venture to express, an anxiety, which may be thought affected by those who cannot know how sincere it must be ; for, in our profession, this is the course of things, that a young man, who, by his limited fortune, or the will of his friends, by absence from his native country,, or by the destina- tion of his future life, is restricted to a few years of irregular, capricious, ill-directed study, throws himself at once into the practice of a profession, in which, according to his ignorance or skill, he must do much good or much harm. Here there is no time for his excursions into that region of airy and fleeting visions, and for his returning again to sedate and useful labour there is no time for his discovering, by the natural force of his own reason, how vain all speculations are.—i-In but a few years, at most, his education is determined ; the limited term is completed ere he have learnt that most useful of all lessons, vili PREFACE. the true plan of study; and his opportunities come to be valued (like every other happiness), only when they are lost and gone. Of all the lessons which a young man entering upon our pro- fession needs to learn, this is, perhaps, the first,—that he should resist the fascinations of doctrines and hypotheses, till he have won the privilege of such studies by honest labour, and a faithful pursuit of real and useful knowledge. Of this knowledge, anatomy surely forms the greatest share.—Anato- my, even while it is neglected, is universally acknowledged to be the very basis of all medical skill.—It is by anatomy that the physician guesses at the seat, or causes, or consequences, of any internal disease.—Without anatomy, the surgeon could not move one step in his great operations ; and those theories could not even be conceived, which so often usurp the place of that very science, from which they should flow as probabilities and conjectures only, drawn from its store of facts. A consciousness of the high value of anatomical knowledge never entirely leaves the mind of the student. He begins with a strong conviction that this is the great study, and with an ardent desire to master all its difficulties : if he relaxes in the pursuit, it is from the difficulties of the task, and the se- duction of theories too little dependent on anatomy, and too easily accessible without its help. His desire for real know- ledge revives only when the opportunity is lost ; when he is to leave the schools of medicine ; when he is to give an account of his studies with an anxious and oppressed mind, conscious of his ignorance in that branch which is to be received as the chief test of his professional skill; or when, perhaps, he feels a more serious and manly impression, the difficulty and im- portance of that art which he is called to practise. Yet, in spite of feeling and reason, the student encourages in himself a taste for speculations and theories, the idle amuse- ments of the day, which, even in his 'own short course, of study, he may observe sinking in quick succession into neglect and oblivion, never to revive ; he aspires to the character of a physiologist, to which want of experience, and a youthful PREFACE. IX fancy, have assigned a rank and importance which it does not hold in the estimation of those who should best know its weak- ness or strength. The rawest student, proud of his physiolo- gical knowledge, boasts of a science and a name which is modestly disclaimed by the first anatomist, and the truest phy- siologist of this or any age. Dr. Hunter speaks thus of his physiology, and of his anatomical demonstration: u Physio- a l°gy> as far as i* 1S known, or has been explained by Haller, " and the best of the moderns, may be easily acquired by a " student without a master, provided the student is acquainted " with philosophy and chemistry, and is an expert and ready " anatomist; for with these qualifications he can read any " physiological book, and understand it as fast as he reads. " In this age, when so much has been printed upon the sub- "ject, there is almost as little inducement to attend lectures " upon physiology, as there would be for gentlemen to attend " lectures upon government, or upon the history of England. " Lectures upon subjects which are perfectly intelligible in " print, cannot be of much use, except when given by some " man of great abilities, who has laboured the subject, and " who has made considerable improvements either in matter " or in arrangement. " In our branch, those teachers who take but litde pains to " demonstrate the parts of the body with precision and clear- " ness, but study to captivate young minds with ingenious " speculation, will not leave a reputation that will outlive them " half a century. " I always have studied, and shall continue my endeavours, " to employ the time that is given up to anatomical studies as " usefully to the students as I can possibly make it—and there- " fore shall never aim at showing what I know, but labour to " show and describe, as clearly as possible, what they ought to " know. This plan rejects all declamation, all parade, all " wrangling, all subtility: to make a show, and to appear " learned and ingenious in natural knowledge, may flatter " vanitv : to know facts, to separate them from suppositions, X PREFACE. " to range and connect them, to make them plain to ordinary " capacities, and, above all, to point out the useful applica- n tions—is, in my opinion, much more laudable, and shall be " the object of my ambition*." * Introductory Lecture published by Dr. Hunter. Edinburgh,7 Sept. 1795. 5 CONTENTS. ® BOOK I. OF THE BONES. CHAP. I. OF THE FORMATION AND GROWTH OF BONES. I. Page ill story of the Doctrines of Ossification, 2 Phenomena of Ossification, - - - 4 BloodVessels and Absorbents of Bones, and Proofs of the Deposition and Reabsorption of the Bony Matter, - 10 Nerves of Bones, and Proofs of the Sensibility of Bones, 11 The Process of Ossification described, - - 12 1. The various Forms and numerous Points of Ossifica- tion, - - - - - 13 2. The heads and Processes of Long Bones, - ib. 3. The Cavity of Long Bones, - - 14 4. The Cancelli, - - - - 15 5. The Marrow, ib. 6. The Lamells, or Bony Plates, - - ib. 7. The Holes of Bones, - - - 16 8. The Vessels, - - 17 9. The Internal Periosteum, - - ib. 10. The External Periosteum, - - - ib. 1!. The Cartilages, - - 18 The Callus and Regeneration of Broken Bones, 20 xu CONTENTS. CHAP. II.—OF THE SKULL IN GENERAL. 22. Page Importance of the Anatomy of the Skull, - - 22 The Tables and Diploe of the Bones of the Skull, - ib. Enumeration and short Description of the Bones of the Cra- nium, - - - 24 The Sutures, - - - - 25 Remarks on the Formation, Nature, and Use of Sutures, 26 CHAP. Ill —DESCRIPTION OF THE INDIVIDUAL BONES OF THE SKULL. 32. Os Frontis, - 32 1. Superciliary Ridge, - - - ib. 2.----------Artery and Nerve, . 33 3. Angular Processes, - - - ib. 4. Nasal Process, - - - ib. 5. Frontal Sinuses, - - - - ib. 6. Frontal Ridge or Spine, - - 36 7. Orbitary Process, - - - - ib. Os Parietalk, - - 37 OsOccipitis, - - 38 i. External Surface, - > _D, 1. Transverse Spines, - . _D. 2. Crucial Spines, - - ib. 3. Posterior Tuberosity, - - 39 ii. Internal Surface, - _ _ - ib. 1. Great Internal Ridge and Tentorium Cerebello Superextensum, - j^. 2. Hollows of the Occipital Bone, - ib. Processes of the Occipital Bone, - > ib! 1. Cuneiform, - - ib! 2. Condyles, - . _ j^' Holes, - . . -40 1. Foramen Magnum, - . - ib. 2. Hole for the ninth Pair of Nerves, - ib 3- ----for the Cervical Vein of the Neck. ib 4. Common Hole, - - - ib Os Tempouis, - - ib! Squamous part, - . _, _ .." Petrous part, - - . _ - ib Processes, 1. Zygomatic, - - - ib 2. Styloid, - - - ib 3. Vaginal, - „ - ib. CONTENTS. XIII Page 4. Mastoid or Mamillary, - - 42 5. Auditory, - - ib. Holes, For the Ear, 1. Meatus Auditorius Externus, - ib. 2. ---- ■---- Internus, * ib. 3. Small Hole receiving a Branch from the fifth Pair of Nerves, - - 43 4. Stylo-Mastoid Hole, - - ib. 5. Hole for the Eustachian Tube, ib. For Blood Vessels, 1. For the Carotid Artery, • 44 2. For the Great Lateral Sinus, called the Common Hole, as formed partly by the Temporal, partly by the Occipital Bone, ib. 3. Small Hok on the outside of the Temporal Bone, ... 45 Os-Ethmoides, ----- ib. 1. Cribriform Plate, - - - ib. 2. Crista Galli, ib. 3. Nasal Plate, or Azygous Process, 46 4. Spongy Bones, - - - ib» 5. Orbitary Plate, or Os Planum, - ib. 6. Os Unguis, - - - 47 7. Cells, ib. Os Sphjenoides, - - - 48 Processes, - - - ib. I. Alx, ib. 2. Orbitary process, - - ib. 3. Spinous process, - - ib. 4. Styloid process, - - - ib. 5. Pterygoid processes, - 49 6. Azygous process, « - - ib. 7. Clynoid processes, - - - ib. Anterior, - - - 50 Posterior, - ib. Sella Turcica, and its Cells, - - ib. Holes, 1. Foramen Opticum, - - ib. 2.---------Lacerum, - 51 3.---------Rotundum, - - ib. 4.---------Ovale, - - ib. 5. ———— Spinale, - - 52 6. Pterygoid, or Vidian Hole, - - ib. Vol.. I. c XIV CONTENTS. CHAP. IV__BONES OF THE FACE AND JAWS. 52- Page Ossa Nasi, - .5* Os Unguis, - „ - ib. Ossa Maxillaria Superiora, Processes, . 1. Nasal, "■■"•!!' 2. Orbitary, - .J*" 3. Malar, . . - ib. 4. Alveolar, - - - 55 Antrum Maxillare, or Highmorianum, »b. Holes, I. Infra Orbitary, - - - 5* 2. Foramen Incisivum, or Anterior Palatine Hole, - - jb^ 3. Posterior Palatine Hole, - • ib. Ossa Palati, - - 58 Processes, 1. Palatal Plate or Process, - - jb. Middle Palatal Suture, * ib. Transverse Palatal Suture, - ib. 2. Pterygoid Process, - - - ib. 3. Nasal Plate or Process, 59 4. Orbitary Process, - ib« Palatine Cells, - - - ib. Ossa Spongiosa, or Turbinata Inferiora, - ib. Vomcr, - - 60 Os Mala:, - - - - 61 Processes, 1. Upper Orbitary, - - - ib. 2. Inferior Orbitary, - - ib- 3. Maxillary, - - - - ib. 4. Zygomatic, - - ib. 5. Internal Orbitary, - . ib. Os Maxillje Inferioris, - . - ib. Processes, - - _ g2 1. Coronoid, - ib. ?. Condyloid, - ib. 3. Alveolar, - *■ - 65 Holes, I. Large Hole on the inner side for the entry of the lower Maxillary Nerve and Artery, 64 2. Mental Hole, - . - ib, CONTENTS. XV CHAP. V—OF THE TRUNK. viz. OF THE SPINE, THORAX, AND PELVIS. Page J. Of the Spine----General View of the Spine—its mo- tions—and the Division of the Vertebra, 64 General Description of a Vertebra, - 65 1. Body of the Vertebra, - - 66 2. Articulating, or Oblique Processes, ib. 3. Spinous Processes, - - * 67 4. Transverse Processes, - - »b. Vertebrae of the Loins, - ib- Vertebrae of the Back, 68 Vertebrae of the Neck, - - ib. Atlas, - - - * ™ Dentatus, . - - ib. Medullary Tube and the Passage of the Nerves, 72 Intervertebral Substance, - - ib. Motions of the Vertebrae, - - 73 H. Of the Thorax, i. Of the Ribs. General Description of a Rib——Division of the Ribs into true and false—Form of a Rib, and place of the Intercostal Artery, - ib. The Parts of the Rib, as the Head, Neck—Sur- face for articulating with the Transverse Pro- cess—Nature of the Joint and Motion of the Rib—Angle of the Rib, - - 75, 76 Size and Length of the Ribs.—The Cartilages of the Ribs, - - - 76 ii. Of the Sternum, and its three Parts, - 77 MI. Of the Pelvis, 79 i. Os Sacrum, - 80 ii. Os Coccygis, » »b. iii. Ossa Innominata, - 82 i. Os Ilium, or Haunch Bone——1. Ala- Spine—Spinous Processes, anterior and posterior----2. Dorsum——3. Costa— 4. Linea Innominata, - 83,84 ii. Os Ischium, or Hip-Bone—— 1. Body— 2. Tuber----3. Ramus, - 84, 85 ill. Os Pubis, orSHARE-BoNE----Body---- Crest——Ramus, - - ib. XVI CONTENTS. Page Recapitulation of the chief Points of the Anatomy of the Pelvis, - - - - 85 Size of the Pelvis in Man and Woman, - 86 Remarks on the separation of the Bones of the pubes during labour, - - - * ^7 CHAP. VI.—BONES OF THE THIGH, LEG, AND FOOT. I. Femur, - - - - 91 1. Body, - - - ib. 2. Head, - - ib. 3. Neck, - - 93 4. Trochanter major, - - ib. 5. Trochanter minor, - - ib. 6. Linea aspera, - - 93 7. Condyles, - - ib. II. Tibia, ... 94 1. Upper head, - - ib. 2. Body, - - - ib. 3. Lower Head—Inner Ankle, - ib. III. Fibula, - - - 96 1. Upper Head, - - ib. 2. Lower Head—Outer Ankle, - ib. IV. Rotula, Patella, or Knee-pan, - 97 V. Tarsus, or Instep, - - 98 1. Astragalus, - - ib. 2. OsCalcis, - - ib. 3. Os Naviculare, - - ib. 4 1 . . 5. Y Cuneiform Bones, - - ib. 6. J 7. Os Cuboides, . , jb, VI. Mktatarsus and its five Bones, - \o\ VII. Toes,—Sesamoid Bones, ib. CHAP. VII.—BONES OF THE SHOULDER, ARM, AND HAND. Shouldek, i. Scapula, or Shoulder-blade, 1q., 1. The flat side of the Scapula, 103 2. The upper flat Surface, - _b, 3. The Triangular Form of the Scapula__ Costa—Basis, - . jb CONTENTS. XV11 Page .4. The Glenoid, or Articulating Cavity, 104 5. The Neck, - - - ib. 6. The Spine, - - ib. 7. The Acromion Process, - - 105 8. The Coracoid Process, - - ib. ii. Clavicle, or Collar Bone, - 106 1. The Thoracic End and Joint, - ib. 2. The Outer End, and its union with the Scapula, - - ib- II. Arm, Os Humeri, - - - ib. 1. Head, - - 107 2. Neck, - - |b. 3. Tuberosities, - - - ib. 4. Groove for the Tendon of the Biceps Muscle, - - ib. 5. Ridges leading to the Condyles, ib. 6. Condyles, - - 108 7. Articulating Surface for the Elbow-joint^ and general explanation of the Joint, ib. 8. Hollows for the Olecranon and Coronoid Process of the Ulna, - - 109 HI. Ulna and Radius, - - ib. I. Ulna, - - - ib. 1. Greater Sigmoid Cavity, formed by 1. Olecranon, - - ib. 2. Coronoid Process, - ib. 2. Lesser Sigmoid Cavity for receiving the Head of the Radius, - 110 3. Ridges, - - ib. 4. Lower Head of the Ulna, - - ib. 5. Styloid Process of the Ulna, - ib. II. Radius, - - - 111 1. Body, - - - ib. 2. Upper Head, - - ib. S. Neck, ib. 4. Point for the Implantation of the Biceps Flexor Cubiti, - - ib. 5. Lower Head, - - ib. IV. Hand and Fingers, - - 112 General Explanation of the Hand and Wrist, Carpus, Metacarpus, and Fingers, ib. I. Carpus, or Wrist, - - 113 1. Row forming the Wrist, - ib. 1. Os Scaphoides, - - - ib. 2. Os Lunare, - * 114 3. Os Cuneiforme, - - ib. 4. Os Pisiforme, - ib, xv'iii CONTENTS. Page 2. Row supporting the Metacarpal Bones, i}* 1. Trapezium, - - ib. 2. Trapezoides, - - ib. 3. Os Magnum, - - 115 4. Os Unciforme, - - ib. II. Metacarpus, - - ib. III. Fingers, - - - 116 BOOK II. OF THE MUSCLES. CHAP. I—MUSCLES OF THE FACE, EAR, AND EYE. I. JVIuscles of the Face, - - ng 1. Occipito Frontalis, - ib. 2. Corrugator Supercilii, - - 119 3. Orbicularis Oculi, or Palpebrarum, 120 4. Levator Palpebral Superioris, - jb, H. Muscles of the Nose and Mouth, - 121 5. Levator Labii Superioris et Alae Nasi, ib* 6.-----------------proprius, . fa T. Levator Anguli Oris, or Levator Communis Labiorum, - . _ J22- 8. Zygomaticus Major, - - ib 9.-----------Minor, - . |b" 10. Buccinator, - _, :l* 11. Depressor Anguli Oris, . 123 12. Depressor Labii Inferioris, or Quadratus Gense, ib. 13. Orbicularis Oris, - . •.' 14. Depressor Labii Superioris, et Alse Nasi, 125 15. Constrictor Nasi, - . jl 16. Levator Men! i, - . fo III. Muscles of the External Ear, - _ j^" 17. Superior Auris, - 12s 18. Anterior Auris, L - ib. 19. Poste/ior Auris, - - - ib. 20. Helicis Major, - - ib. 21. Helicis Minor, - - jb„ CONTENTS. XljC Page 22. Tragicus, - 126 23. Antitrtgicus, »- - ib. 24. Transversus Auris, - - ib. IV. Muscles of the Eye-ball, - - 127 General Explanation of these Muscles, - ib. 25. Rectus Superior, 128 26. Rectus Inferior, - - ib. 27. Rectus Internus, - - ib. 28. Rectus Externus, - - ib. 29. Obliquus Superior, - - ib. 30. Obliquus Inferior, - - 129 CHAP. II—MUSCLES OF THE LOWER JAW, THROAT, AND TONGUE. I. Muscles of the Lower Jaw, - - 130 31. Temporalis, - - - ib. 32. Masseter, - ib. 33. Pteregoideus Internus, or Major, - 131 34. Pteregoideus Externus, or Minor, - ib. II. Muscles of the Throat and Tongue, ib. Explanation of certain Bones and Cartilages forming the basis of the Throat and Tongue, and the centre of their motions, - - ib. 1. Os Hyoides,—Its Cornua,—Its Appendices, or perpendicular Processes, - ib. 2. Larynx, Trachea, or Windpipe, - 133 1. Scutiform, or Thyroid Cartilage, ib. 2. Cricoid Cartilage, - - ib. 3. Arytenoid Cartilages, and Rima Glottidis formed by them, - - ib. 4. Epiglottis, - - 134 Recapitulation and view of the constitution of the La- rynx, - - - ib. >. Muscles of the. Throat, - - ib. 1. Muscles which pull the Throat down, 135 34. Sterno-hyoideus, - - ib. 35. Sterno thyroideus, - ib. 36. Omo-hyoideus, - - ib. Action of these Muscles, - - ib. -. Muscles which move the Throat upwards, ib. 37. Mylo-hyoideus, - - ib. 38. Genio-hyoideus, - - - 136 39. Stylo-hyoideus, - - ib*. 40. Digastricus, or Biventer Maxilla Inferioris, in 3. Muscles moving the parts and cartilages, of the XX CONTENTS. Page Larynx upon each other, - *f 41. Hyo-thyroideus, - jb. 42. Crico-thyroideus, - - )b. 43. Musculus Arytenoideus Transversus, - ib. 44. Musculus Arytenoidaus Obliquus, - 138 45. Crico-Arytenoideus Posticus, - )b« 46. Crico-Arytenoideus Obliquus, - ib. 47. Thyreo-Arytenoideus, - - 'b. 4. Muscles of the Palate and Pharynx, - ib. 48. Azygus Uvulae, - * 159 49 Levator Palati Mollis, - - ib. 50. Circumflexus Palati, or Tensor Palati Mollis, ib. 51. Constrictor Isthmi Fauschium, - 140 52. Parato-Pharyngeus, - - ib. Pharynx explained, - - ib. 53. Stylo-pharyngeus, - - ib. 54. Constrictor Superior, - - 141 55. Constrictor Mcdius, - - ib. 56. Constrictor Inferior, - - ib. 57. Vaginalis Guise, - - 142 Muscles of the Tongue, - - ib. 58 Stylo-Glossus, - - ib. 59. Hyo-Glossus, - - ib. 60. Genio-glossus, - - ib. 61. Lingualis, - - ib. Motions of the Tongue performed by these Muscles, - - 143 CHAP. Ill—OF THE MUSCLES OF THE ARM, INCLU- DING THE MUSCLES OF THE SCAPULA, ARM, FORE- ARM, AND HAND. I. Muscles ok the Scapula, . . ib. i. Muscles moviHg the Scapula upwards and back- wards, . . .144 62. Trapezius, . . jb. 63. Levator Scapulae, or Levator Proprius Angu- laris, . . . k45 64 Sc 65. Rhomboides, . t ib. 1. Minor, . ib 2. Major, . . '. ib; ii. Muscles which move the Scapula downwards and forwards, . . # |4S 66. Serratus Major Amicus, . . ib# 67. Pectoralis Minor, . . fo 68. Subclavianus, . . jb. Motions of the Scapula, • . . 147 GONTENT.fi. XX! Page IT. Muscles moving the Os Humeri, or Arm Bone, 147 69. Pectoralis Major, - - ib. 70. Latissimus Dorsi, - - 148 71. Deltoides, - - 149 72. Coraco-brachialis, - - 150 73. Supra Spinatus, - - ib. 74. Infra Spinatus, - - 151 75. Teres Minor, - - ib. 76. Teres Major, - - ib. 77. Subscapularis, - - 152 Motions of the Humerus, and Use and Effect of each of these Muscles in forming and strength- ening the Joint, - - ib. III. Muscles moving the fore-arm, - 154 i. Muscles bending the Fore-arm, - ib. 78. Biceps Brachii Flexor, - - ib. 79. Brachialis Internus, - - ib. ii. Muscles extending the Fore-arm, - 155 80. Triceps Extensor, ib. 81. Anconeus, ... 155 IV. Muscles situated on the Fore-arm, moving the Radius, Carpus, and Fingers, - - ib. Fascia of the Arm, - - - ib. Arrangement of these Muscles, the points of ori- gin and insertion, and the motions of pro- nation and supination, flexion, and extension explained, - - ib. i. Flexors, arising from the Inner Condyle, 157 82. Pronator Teres Radii, - - 159 83. Palmaris Longus, ... ib. 84. Palmaris Brevis, or Cutaneus, - 1 eo 85. Flexor Carpi Radialis, - - ib. 86. Flexor Carpi Ulnaris, - - 161 87. Flexor Digitorum Sublimis, - ib. 88. Flexor Digitorum Profundus, vel Perforans, 162 89. Lumbricales, - - - 163 90. Flexor Longus Pollicis, - - ] 64 91. Pronator Quadratus, - - ib. ii'. Extensors arising from the Outer Condyle, 165 92. Supinator Radii Longus, - - ib. .93. Extensor Carpi Radialis Longior, - 166 94. Extensor Carpi Radialis Brevior, - ib. 95. Extensor Carpi Ulnaris, - 167 96. Extensor Digitorum Communis, - ib. 97. Extensor Minimi Digiti, or Auricularis, 168 98. Extensor Primus Pollicis, "J - 169 99. Extensor Secundus Pollicis, J> - 170 100. Extensor Terlius Pollicis, J - ib. Vol. I. d XX11 CONTENTS. Page 170 101. Indicator, - .171 102. Supinator Brevis, - ib V. MUSCLK-S SKATkD ON THE HAND, ' ^ ^ Table of these Muscles, ib 103. Abductor Pollicis, j 173 ib. 174 104. Opponens Pollicis, i 105. Flexor Brevis Pollicis, \ 106. Adductor Pollicis, J " \'J 107. Abductor Minor Digiti, j • 108. Flexor Parvus Minimi Digiti, i> *"• 109. Adductor Minimi Digiti, J 110. Abductor Indicis, 1 Ii. Interossei Interni, 112. Interossei Externi, ib. ib. (HAP IV.—MUSCLES OF RESPIRATION, OR OF THERiBS. General Explanation and Table of these Muscles, 176 113. Serratus Superior Posticus, - - ]7?' 114. Serratus Inferior Posticus, - ib. 115. Levaiores Costarum, - - *78 116. Intercoslales, - - - ib. 117. Triangularis Sterni, or Sterno-Costalis, 179 CHAP V__MUSCLES OF THE HEAD, NECK, AND TRUNK. I. Muscles of thk Head and Neck, 118. Splenius, - - - 180 1 .9. Complcxus, ... ib. 120. rritchelo-mastoideus, - - 182 121. Rectus Minor, - - ib. 12-i. Rectus Major, ... jb. 123. Obliquus Superior, - - 1S3 124. Obliquus Inferior, - - ib. II. Muscles of the Trunk, 125. Quadratus Lumborum, - - ib. 126. Longissimus Dorsi, - - 184 127. Sucro Lumbalis, - - 185 128. Cervicalis Descendens, - - ib. 129. TransveisalU Colli, ' - 186 CONTENTS. xxiii Page Arrangement of the intricate set of Muscles filling up the hollows and interstices among the Spines and Processes of the Vertebra, - - - lf? 130. Spinalis Cervicis, 131. Spinalis Dorsi, 132. Semi spinalis Dorsi, 133. Muitifidus Spinx, 134. Inter-spinales Colli, Dorsi, et Lumborum, 189 135. Inter transversales, - - lb- III. Muscles on the fork part of the Head and Neck, completing the Catalogue of those belonging to the Spine, - 136. Platysma Myoides, 137. Mastoidtus, - - - Iy~ ]>3B. Rectus Internus Capitis Major, - Jb. 139. Rectus Internus Capitis Minor, - »>• 140. Rectus Capitis Lateralis, - - jb 141. Longus Colli, 142. Scalenus, CHAP. VI—OF THE MUSCLES OF THE ABDO- MEN, AND OF THE DIAPHRAGM. ib. 183 ib. ib. ib. ib. 191 ib. 192 I. Muscles of the Abdomen, - - Importance of the Anatomy of the Abdominal Mus- cles,—General Explanation of these Muscles,— their Uses,— \rrangement, - - #,b' 143. Obliquus lixternus, - - J. 144. Obliquus'Internus, - - 19* 145. Transversalis Abdominis, - - ™- 146 Recti, - " .5 147. Pyramidalis, - " lb* Explanation of the Lines, Rings, 8cc. of the Abdo- minal Muscles, - - " ] ?/> 1. Linea \lba, - " J*. 2. Linea Semilunaris, - »>. 3. Sheath for the Rectus, - >b. 4. Umbilicus, - - 19/ 5. Ring of the Abdominal Muscles, ib. 148. Cremaster Muscles of the Testicle, - 198 6. Ligament of the Thigh, - ™c Explanation of the different kinds of Hernia, and the points at which the bowels are pro- truded, - " -ib. If ses of the Abdominal Muscles, - 199 xxiv CONTENTS. Page H. Diaphragm, - - - .200 149. The Diaphragm, - - "*■ 1. The Greater, or Upper Muscle of the Diaphragm, - - *b- 2. The Lesser Muscle of the Diaphragm, ib. 3. The Tendon in the centre of the Dia- phragm, - - 201 Vessels perforating the Diaphragm, ib. 1. Aorta, - - jb- 2. Oesophagus, - - ib- 3. The Great Vena Cava, - 202 The Tendon of the Diaphragm, - ib. Uses of the Diaphragm, - - ib; CHAP. VII—THE MUSCLES OF THE PARTS OF GENERATION, AND OF THE ANUS AND PE- RINEUM. General idea of these Muscles, - - 203 Structure of the Penis, - 204 150. Erector Penis, - - - ib. 151. Transversalis Perinaei, - - ib. 152. Accelerator, - - - ib. 153. Sphincter Ani, - - 205 154. Levator Ani, - - - ib. 155. Musculus Coccygxus, - - 206 Perinxum,—the point where all these Muscles are united, ib. Course of the Incision in Lithotomy, - _ ib. CHAP. VIII—MUSCLES OF THE THIGH, LEG, AND FOOT. I. Muscles moving the thigh bone, _ _ 207 General Description of these Muscles,—Classification and Arrangement of them,—and Table of their Implantations, and of the Motions which they perform, - - . 20S Fascia of the Thigh, - - ib 156 Musculus Fascialis, or Tensor Vaginse Fe- moris, - _ 2Qg 157. Psoas Magnus, - . - 210 158. Psoas Parvus, - . -" ib 159. Iliacus Internus, - ;.. CONTENTS. 160. Pectineus, or Pectinalis, 161. Triceps Femoris, 1. Adductor Longus, 2 Adductor Brevis, 3. Adductor Magnus, 162. Obturator Externus, 163. Glutaeus Maximus, - 164 Glutxus Medius, or Minor, 165. Glutxus Minimus, 166. > n . . J67 > Gemini, - 168. Pyriformis, - 169. Obturator Internus, 170. Quadratus Femoris, Motions of the Thigh, and Action of these Muscles, II. Musclks of THti Leg, An ar^emtnt of these Muscles, i. Ext >. NsoRh of the Leg, 171. R: otus Femoris, or Rectus Cruris, 172. < ru-xus, Su:>-ciuixi, being blips only of the Crurxus, 173 v'astus Kxternus, ... 174 Vastus Internus, Uses of these Muscles, - ij. Flexors of the Lie, - - 175. Sartonus, - 176 Gracilis, or Rectus Internus Femoris, 177. Semitendinous, 178. Semimembranosus, 179. Poplitxus, 180. Biceps Cruris, - JII. Muscles of the Foot, Arrangement, .... i. Ext. nsors, - - - - 18. Gastrocnemius, - - - 182. Soleus, 183 Plantaris, 184. Peronxus Longus, 185. Peronxus Brevis, 186. Tibialis Posticus, ii. Flexor, - 187. Tibialis Anticus, iV. Musclks of the Toes, - 188 Flexor Longus Pollicis, 189. Flexor Longus Digitorum Pedis, Perforans, 190. Massa Carnea J. Sylvii, or Planlx Pedis, 191. Flexor Brevis Digitorum, 192. Lumbricales, V_\i CONTENTS. Page 193. Extensor Longus Digitorum Pedis, 231 194. Peronaeus Tertius, - " . 195. Extensor Digitorum Brevis, - lL^ 196. Extensor Pollicis Propnus, - - 253 Crucial Ligament, - " 234 197. Abductor Pollicis, ") - J". 198. Flexor Brevis Pollicis, £> - - jb. 199. Adductor Pollicis, J - - ib. 200. Transversalis Pedis, - - 235 201. Abductor Minimi Digiti, - - jb. 202. Flexor Brevis Minimi Digiti, - jb. 203. Interossei Interni, - - ib. 204. Interossei Externi, - - 236 Plantaris Aponeurosis, - - ib. CHAP. IX.—OF THE MUSCULAR POWER. CHAP. X—OF THE TENDONS, LIGAMENTS, BURSE, AND ALL THE PARTS WHICH BE- LONG TO THE BONES OR MUSCLES, OR WHICH ENTER INTO THE CONSTITUTION OF A JOINT. General Explanation of the Tendons, Ligaments, &c 248 Of the Forms of the Cellular Substance, - - 250 1. Its Cells, and their use, - - ib. 2. Bursx Mucosx, - - - ib. 3. Vaginxor Fascix, - - - 251 4. Tendons, - - - ib. 5. Periosteum, - - - 252 6. Vagina, or Sheaths of Tendons, - ib. 7. Capsules of the Joints, - - 253 8. Ligaments of Joints, - - - ib. Recapitulation and Review of the connections of these parts, ib. Constitution and Nature of those less feeling parts,—Almost insensible in health,—slow to inflame,—their inflammation very violent, though slow,—diseases to which they are liable, 254 BOOK III. OF THE JOINTS. CHAP. I—JOINTS OF THE HEAD AND TRUNK. T. Joints of the H'. ad and Spine, - - 258 The Motions ol the Head and Spine, - ib. CONTENTS. XXVll Page The Provisions for these Motions, - 259 i. Joint of the Head with ihe Neck, - ib. 1. Articulation of the Occiput and Atlas, ib. Form of the Joint and Capsules for the Condyles, ib. Flat membranous Ligament from the Ring of the Atlas to the Ring of the Occipital Hole, ib. 2. Articulation of the Atlas with the Dentatus, ib. Capsules betwixt the Condyles of the Vertebrx, ib. Transverse Ligament embracing the Neck of the Tooth-like Process----Capsular Ligament, ib. Ligament betwixt the Tooth-like Process and Occipital Hole, - - ib- ii. Joints of the Common Vertebrx with each other, ib. Intervertebral Substance, and Intervertebral Liga- ments, .... 260 External or Anterior Vagina, or Ligament of the Spine, - ib. Internal Ligaments, - - 261 Ligamenta Subflava Crurum Processuum Spi- nosorum—Membranx Interspinals—Liga- menta Processuum Transversorum, - ib. Posterior or Internal Ligament of the Spine, ib. Apparatus Ligamentosus Colli, - ib. II Joint of the Lower Jaw, ... 262 III. Joints of the Ribs, - - 263 Ligamenta Capitelli Costarum, - - ib. Ligamentum Transversarium Externum, - ib. -----—-------------— Internum, - ib. Capsule and Ligaments belonging to the Cartilages, 264 CHAP. II—JOINTS OF THE SHOULDER, ARM, AND HAND. L Joints of the Clavicle, - - - ib. With the Sternum, - - ib. With the Scapula, .... 265 II. Joint of the Shoulder, - - - ib. III. Joint of the Elbow, ... 267 The General Capsule of the whole Joint, ib-. The Lateral Ligaments, External and Internal, ib. The Coronary Ligament of the Ulna, - 268 Accessory Ligaments, - - ib. IV. Wrist, ib. Articulation of the Scaphoid and Lunated Bones with the Scaphoid Cavity of the Radius, - 269 Articulation of the Radius with the Ulna for the tur- ning Motions of the Hand, - - ib. Articulation of the Bones of the Carpus with each other, ib. Xxviii CONTENTS. Page Articulations of the Metacarpus, - - 270 V. Joints of the Fingers, - - - ib. CHAP. Ill—JOINTS OF THE THIGH, LEG, AND ANKLE. I. The Hip-Joint, - - - - 272 The Ligamentum Labri Cartilaginei Transversale, ib. The Capsule of the Joint, - - ib. The Internal Ligaments, - 273 II. Knee-Joint, - - . 274 1. The External Ligaments, . - » ib. Capsule—and Ligamentum Posticum Winslowii, 275 Lateral Ligaments, - - ib. Ligamentum Laterale Internum, - - ib. -------------------Externum Longior, ib. -------------------Brevior, - ib. 2. The Internal or Crucial Ligaments of the Knee, 276 Posterior Crucial Ligament, - - ib. Anterior------------, - - ib. Semilunar, or moveable Cartilages, - ib. Ligamentum Mucosum—and Ligamentum Alare Majus et Minus, - . 277 Bursas Mucosx of the Knee-joint, - 278 Recapitulation, explaining the Constitution of this Joint, and uses of its several parts, - - fa III. Articulation of the Fibula with the Tibia, 280 IV. Ankle-Joint, - - - - ib. Ligamentum Superius Anticum, - jb. -------------------Posticum, - jb. ■----------Inferius Posticum, - ib. Capsule, - - - . 281 Ligamentum Deltoides, - _ ib_ ----------Fibulx Anterius, - _ jb. ----------------Perpendiculare, - ib! --------Inter Fibulam et Astragalum Posterius, ib' V. Joints of the Foot, " - - ib Articulations of the Bones of the Tarsus with each other, 282 Joints of the Metatarsus and Toes, - fo. Aponeurosis Plantaris Pedis, - . jj * Bursx Mucosx of the Ankle and Foot, . 28 " Conclusion and Enumeration of the Joints, _ 284 THE ANATOMY OF THE BONES, MUSCLES, AND JOINTS, OF THE BONES. CHAP. L OF THE FORMATION AND GROWTH OF BONES. IT is not easy to explain, in their natural order, the various parts of which the human body is composed ; for they have that mutual dependence upon each other, that continual circle of action and re-action in their various functions, and that in- tricacy of connection, and close dependence, in respect to the individual parts, that, as in a circle there is no point of preference from which we should begin to trace its course, so in the human body there is no function so insulated from the other functions, no part so independent of other parts, as to determine our choice. We cannot begin without hesitation, nor hope to proceed in any perfect course; yet, from whatever point we begin, we may so return to that point, as to represent truly this consent of functions, and connection of parts, by which it is composed into one perfect whole. The bones are framed as a basis for the whole system; fit- ted to support, defend, and contain the more delicate and noble organs. They are the most permanent and unchange- able of all parts of the bodv. We see them exposed to the seasons, without suffering the smallest change ; remaining for ages the memorials of the dead ; the evidence of a former race of men exceeding ours in strength and stature ; the only remains of creatures which no longer exist j the proofs of such changes on our globe, as we cannot trace but bv thesi- uncer- Vol. I. V 2 OF THE FORMATION tain marks. Thus we are apt to conceive, that even in the living bodv, bones are hardly organized ; scared}' partaking, of life ; not liable, like the soft parts, to disease and death. But minute anatomy, the most pleasing part of our science, unfolds and explains to us ti■■• internal structure of the bones ; •shows their myriads of vessels ; and proves them to be as full of blood as the most succulent and fleshy parts ; having, like them, their periods of growth and decay ; being as liable to accidents, and as subject to internal disease. The phenomena of fractured bones first suggested some in- distinct notions of tl.c way in which bone might be formed. It was observed, that in very aged men, a hard crust v/a« often formed upon the surface of the bones ; that the fluid ex- uding into the joints of gouty people, sometimes coagulated into a chalkv mass; Le Dran had seen in a case of spina ven- tosa, or scrophulous bone, an exudation which flowed out like wax, and hardened into perfect bone ; Daventer had seen the juice that exuded from a split in a bone, coagulate into a bony crust; and it was thought to be particularly well ascertained, that callus was but a coagulablejuicc, which might be seen exuding directly from the broken ends of a bone, and which gradually coagulated into hard bone. The best physiologists did not scruple to believe, that bones, and the callus of broken bones, were formed of a bony juice, which was deposited by the vessels of the part, and which passing through all the suc- cessive conditions of a thin uncoagulated juice, of a transpa- rent cartilage, and of soft and flexible bone, became at last, by a slow coagulation, a firm, hard, and perfect bone ; de- pending but little upon vessels or membranes, either for its generation or growth, or for nourishment in its perfect state. But this coagulation is a property of dead matter, which hap no place in the living system ; or if blood or mucus do ever coagulate within the body, it is only after it is separated from the system. Coagulation is a sort of accident in the living body ; and it is not to be believed that the accidental concourse of parts should form the perfect system of a livinp bone; nor that coagulation, an irregular uncertain process" should keeppace with the growth of the living parts ; that a bene which is completely organized, and a regular part of the living system, should, in all its progress towards this perfect state, be merely inanimate, inorganized matter: vet this opinion once prevailed ; and if other theories were at tha* time proposed, they did not vary in any very essential poir/ from this first notion. De Heide, a surgeon of Amsterdam believed that bone or callus was not formed from a coagulable juice, but from the blood lt.s-.-lf. He broke the bones of ani- AND GROWTH OP BONES. 5 mals, and, examining them at various points of time, he ne- ver failed (like other speculators) to find exactly what he de- sired to find. In "every experiment," he found a great effu- sion of blood among the muscles, and round the broken bone : and he as easily traced this blood through all the stages of its progress : on the first day red and fluid ; by and by coagula- ted ; then gradually becoming white, then cartilaginous, and at last (by the exhalation of its thinner parts) hardening into perfect bone. It is very singular, that often those who abjure theory, and appeal to experiments, who profess only to deliver facts, are least .of all to be trusted ; for it is theory which brings them to try experiments, and then the form and order ; and even the result of such experiments, must bend to meet the theories which they were designed to prove. It is by this decep- tion that the authors of two rival doctrines arrive at opposite conclusions by facts directly opposed to each other. Du Ha- mel believed, that as the bark formed the wood of a tree, add- ing, by a sort of secretion, successive layers to its growth ; so the periosteum formed the bone at the first, renewed it when spoiled or cut away, and, when broken, assumed the nature of bone, and repaired the breach. He broke the bones of pigeons, and, allowing them to heal, he found the perios- teum to be the chief organ for reproducing bone. He found that the callus had no adhesion to the broken bone, and was easily separated from the broken ends which remained rough nnd bare. And, in pursuing these dissections, he found the periosteum fairly glued to the external surface of the new bone ; or he found rather the callus or regenerated bone to be but a mere thickening of the periosteum, its layers being sepa- rated, and its substance swelled. On the first days he found the periosteum thickened, inflamed, and easily divided into many lamellae, or plates ; but while the periosteum was suffer- ing these changes, the bone was in no degree changed. On the following days, he found the tumour of the periosteum in- creased at the place of the fracture, and extending further along the bone ; its internal surface already cartilaginous, and always tinged with a little blood, which came to it through the vessels of the marrow. » He found the tumour of the peri- osteum spongy, and divisible into regular layers, while still the ends of the bone were unchanged, or only a little rough- ened by the first layer of the periosteum being already con- verted into earth and deposited upon the surface of the bone : and in the next stage of its progress, he found the periosteum ■firmly attached to the surface of the callous mass. By wound- ing, not breaking, the bones, he had still a more flattering ap- 4 OF THE 'FORMATION pearanceof a proof; for having pierced them with holes, lie found the holes filled up with a sort of tompion, proceeding from the periosteum, which was thickened all round them. In an early stage, this plug could, by drawing the periosteum, be pulled out from its hole : in a more advanced stage, it was inseparably united to the bone, so as to supply the loss. Haller, doubting whether the periosteum, a thin and deli- cate membrane, could form so large a mass ot bone or callus, repeated the proofs ; and he again found quite the reverse ot all this: that the callus, or the original bone, was in no de- gree dependent on the periosteum, but was generated from the internal vessels of the bone itself: that the periosteum did indeed appear as early as the cartilage which is to produce the bone, seeming to bound the cartilage, and give it form ; but that the periosteum was at first but a loose tissue of cellu- lar substance, without the appearance of vessels, or any mark of blood, adhering chiefly to the heads or processes, while it hardly touched the body of the bone. He also found that the bone grew, became vascular, had a free circulation of red blood, and that then only the vessel of the periosteum began to carry red blood, or to adhere to the bone. We know that the bones begin to form in small nuclei, in the very centre of their cartilage, or in the very centre of the yet fluid callus, far from the surface, where they might be assisted by the pe- riosteum ; and that ossification begins.first in the middle of the long bones, where the periosteum does not adhere, and is formed much later in the heads and processes, whose connec- tion with the periosteum is very close. Thus has the formation of bone been falsely attributed to a gelatinous effusion, gradually hardened ; or to that blood which must be poured out from the ruptured vessels round a fractured bone ; or to the induration and change of the peri- osteum, depositing layer after layer, till it completed the form of vhe bone. But when, neglecting theory, we set ourselves to examine with an unbiassed judgment, the process of nature in forming the bones, as in the chick, or in restoring them, as in broken limbs, a succession of phenomena present themselves the most orderly, beautiful, and simple, of any that are recorded in the philosophy of the animal body : for if bones were but condensed gluten, coagulated blood, or a mere deposition from the periosteum, they were then inorganized, and out of the system, not subject to change, nor open to disease ; liable indeed, to be broken, but without any means of being healed again : while they are, in truth, as fuliy organized, as per- meable to the blood, as easily hurt, and as easily healed as AND GROWTH OF BONES. . 5 sensible to pain, and as regularly changed as the softer parts are. We are not to refer the generation and growth of bone to any one part. It is not formed by that gelly in which the bone is Lived ; nor by the blood which is circulating in it ; nor by the periosteum which covers it; nor by the medullary membrane with which it is lined : but the whole system of the bone, of which these are parts only, is designed and planned, is laid out in the very elements of the body, and advances to ripeness by the concurring action of all its parts. The arte- ries, by a determined action, deposite the bone ; which is for- med commonly in a bed of cartilage, as the bones of the leg or arm are ; sometimes betwixt two layers of membrane, like the bones of the skull, where true cartilage is never seen. Often the secretion of the bony matter is performed in a dis- tinct bag, and there it grows into form, as in the teeth ; for each tooth is formed in its little bag, which, by injection, can be filled and covered with vessels. Any artery of the body may assume this action, and deposite bone, which is some- times also formed where it should not be; in the tendons and in the joints, in the great arteries, and in their valves, in the flesh of the heart itself, or even in the soft and pulpy substance of the brain. All the bones of the body, both in the human foetus, and in other animals, are merely cartilage before the time of birth. The whole foetus is gelatinous ; the bones are a pure, almost transparent and tremulous gelly ; they are iLxible, so that a long bone can be bent into a complete ring ; and no opacity, nor spot of ossification is seen. This cartilage is never hardened into bone ; but, from the first, it is in itself an organized mass. It has its vessels ; which are at first transparent, but which soon dilate, and whenever the red colour of the blood begins to appear in them, ossification very quickly follows, the arteries being so far en- larged as to carry the coarser parts of the blood. The first mark of ossification is an artery, which is seen running into the centre of the gelly in which the bone is to be formed. Other arteries soon appear; overtake the first; mix with it, and form a net-work of vessels ; then a centre of ossification begins, stretching its rays according to the length of the bone, and then the cartilage begins to grow opaque, yellow, brittle ; it will no longer bend, and the small nucleus of ossification is felt in the centre of the bone, and when touched with a sharp point, is easily known by its gritty feel. Other points of ossi- fication are successively formed ; the ossification being always foretold by the spreading of the artery, and by the arrival of led blood. Every point of ossification has its little arteries, 6 OF THE FORMATION and each ossifying nucleus has so little dependence on the car- tilage in which it is formed, that it is held to it by these arte- ries only ; and when the ossifying cartilage is cut into thin slices, and steeped in water till its arteries rot, the nucleus of ossification drops spontaneously from the cartilage, Laving the cartilage like a ring, with a smooth and regular hole where the bone lay. The colour of each part of a bone is proportioned exactly to the degree in which its ossification has advanced. When ossification begins in the centre of the bone, redness also ap- pears ; indicating the presence of those vessels by which the bony matter is to be poured out. When the bony matter be- gins to accumulate, the red colour of those arteries is obscured, the centre of the bone becomes yellow or white, and the colour seems be removed towards the ends of the bone. In the centre, the first colouring of the bone is a cloudy, diffused and general red, because the vessels are profuse. Beyond that, at the edges of the first circle, the vessels are more scattered, and distinct trunks are easily seen, forming a circle of radia- ting arteries, which point towards the heads of the bone. Beyond that, again, the cartilage is transparent and pure, be- ing yet untouched with blood ; the arteries have not reached it, and its ossification is not begun. Thus, a long bone, while forming, seems to be divided into seven variously coloured zones. The central point of most perfect ossification is yel- low and opaque. On either side of that, there is a zone of red. On either side of that again, the vessels being more scattered, form a vascular zone,* and the zone at either end is transparent or white. The ossification follows the vessels, burying and hiding those vessels by which it is formed : the yellow and opaque part expands and spreads along the bone : the vessels advance towards the heads of the bones : the whole body of the bone becomes opaque, and there is left only * It ii curious to obferves how completely vafcular the bone of a chicken is be- fore the ossification have fairly begun ; how the ossification having begun over- takes the arteries, and hides them, changing the tranfpartnt and vafcular part of the bone into an opaque white; how, by peeling off the periofteum, bloody dots are feen, which shows a living connection and commerce of veffels betwixt the periofteum and the bone ; how, by tearing up the outer layers of the tender bone the vafcularity of the inner layers is again expofed But of all the proofs ol the' vafcularity of bones and depofition of the bony matter, the moft beautiful is that of our common preparations ; where,after filling with injection the arteries of an adult bone, by its nutritious veffels, we, by corroding the bone with mineral acids, diffolve the earth, leaving nothing but the tranfparent gtlly, and thus re- ftore the bone to its original cartilaginous flare ; then the veffels appear in fuch profusion, that the bone may be compared in vafcularity with the foft parts, and it is feen that its arteries were not annihilated, but its high vafcuhrify ei.!y con- cealed by the depofition of the bony parts. AND GROWTH OF BONES. 7 a small vascular circle at either end : the heads are separated from the body of the bone by a thin cartilage ; and the vessels of the centre, extending still towards the extremities of the bone, perforate that cartilage, pass into the head of the bone^ and then its ossification also begins, and a small nucleus of ossification is formed in its centre. Thus the heads and the body are, at the first, distinct bones formed apart and joined by a cartilage ; and they are not united till the age of fifteen Or twenty years.. The vessels are seen entering in one large trunk (the nutri- tious arten) into the middle of the bone : from that centre they extend in a radiated form towards either end, and the fibres of the bone are radiated in the same direction ; there are furrows betwixt the rays, and the arteries run along in the furrows of the bone, as if the arteries were forming these ridges, secreting and pouring out the bony matter, each arte- ry piling it up on either side to form its ridge. The body of the bone is supplied by its own vessels ; the heads of the bone are supplied by the extremities of the same trunks which per- forate the dividing cartilage like a sieve ; the periosteum ad- hering more firmly to the heads of the bone, it brings assistant arteries from without, which meet the internal trunks, and assist the ossification ; but with every help, the ossification is not accomplished in many years. It is by the action of the vessels that all the parts of the hu- man body are formed ; fluids and solids, each for its respec- tive use. The blood is formed by the action of the vessels, and all the fluids are in their turn formed from the blood. We see in the chick, where there is no external source from which its red blood can be derived, that red blood is formed within its own system. Every animal system, as it grows, assimi- lates its food, and converts it to the animal nature, and so in- creases the quantity of its red blood : and as the red blood is thus prepared by the actions of the greater system, the actions of particular vessels prepare various parts : some to be added to the mass of solids, for the natural growth ; others to supply the continual waste ; others to be discharged from the body r.s effete, and hurtful, or to allow new matter to be received ; others again to perform certain offices within the bodv, as the secretion of semen, of saliva, of bile, or of urine. Thus the body is furnished with various apparatus for performing vari- ous offices, and for repairing the waste. These are the secre- tions, and the formation of bone is one of these. The plan of the whole body lies in the embryo, in perfect order, with all its forms and parts. Cartilage is laid in the place of bone, and preserves its form for the future bone, with all its appara- 3 OF THE FORMATION tus of surrounding membranes, its heads, its processes, and its connection with the soft parts. The colourless arteries of this pellucid, but organized mass of cartilage keep up its growth ; extend, and yet preserve its form ; and gradually en- larging in their own diameter, at last receive the entire blood. Then the deposition of earthy matter begins. The bone is deposited in specks, which spread and meet, and form them- selves into perfect bone. While the bone is laid by arteries, the cartilage is conveyed away by the absorbing vessels ; am! while they convey away the superfluous cartilage, they model the bone into its' due form ; shape out its cavities, cancclli, and holes; remove the thinner parts of the cartilage, and harden it into due consistence. If such organization of arteries to deposite bone, and of absorbents to take up the cartilage and make room for the os- seous matter, be necessary in the formation and growth, it is no less necessary for the life and health of the full-formed bone. Its health depends on the regular deposition and re-absorption, moulding and forming the parts ; and by various degrees of action, bone is liable to inflame, to ulcerate, to rot and spoil, to become brittle by too much secreted earth, or to become soft by a greedy diseased absorption of its earthy parts. The earth, which constitutes the hardness, and all the useful pro- perties of bone, is dead, inorganized, and lies in the intersti- ces of the bone } where it is united with mucus, to give it consistence and strength; furnished with absorbents to keep it in health, and carry off its wasted parts ; and pervaded by vessels to supply it with new matter. The cartilage is itself a secretion, to which the full secretion of bone succeeds, as the arteries grow stronger in their secreting office : for in a broken limb there is first a thin effusion, then a tremulous gelly, then radiated vessels, then ossifying spots, and these running to- gether form perfect bone. If the broken limb be too much moved during the cure, then the secreting arteries are inter-; rupted in their office ; perfect bone is never formed ; it re- mains a cartilage ; and an unnatural joint is produced: but We cut the surface of these cartilages, and then the vessels are opened again, the process is renewed, and the bones unite : or even by rubbing, by stimulating, by merely cutting the sur- rounding parts, the vessels are made active, and their secre- tion is renewed. During all the process of ossification, the absorbents proportion their action to the stimulus which is ap- plied to them ; they carry away the serous fluid, when gelly is to take its place ; they remove the gelly, as the bone is laid • they continue removing the bony particles also, which (as in a ircle) the arteries continually renew. AND GROWTH OF BONES. 9 Nothing can be more curious than this continual renovation Rnd change of parts, even in the hardest bones. We are ac- customed to say of the whole body, that it is daily changed ; that the old particles are removed; and new ones supply their place ; that the body is not now the same individual body that it was ; but it could not be easily believed that we speak only by guess concerning the softer parts, what we know for cer- tain of the bones. It was discovered by chance, that animals fed upon the refuse of the dyer's vats, received so much of the colouring matter into the system, that the bones were tinged by the madder to a deep red, while the softer parts were un- changed ; no tint remaining in the ligaments nor cartilages ; in the membranes^ vessels, nor nerves ; not even in the delicate vessels of the eye. It was easy to distinguish by the micro- scope, that such colour was mixed with the bony matter, and resided in the interstices only, but did not remain in the ves- sels of the bone, which like those of all the body had no tinge of red ; while our injections again fill the vessels of the bone, make all their branches red, but do not affect the colours of the bony part. When madder is given to animals, withheld for some time, and then given again, the colour appears in their bones; is removed; and appears again, with such a sud- den change as proves a rapidity of deposition and absorption exceeding all likelihood or belief. All the bones are tinged in twenty-four hours : in two or three days their colour is very deep : and if the madder be left off but for a few days, the red colour is entirely removed. This tinging of the bones with madder, was the great in- strument employed by Du Hamel, for proving by demonstra- tion, that it was by layers from the periosteum that the bone was formed ; and how very far the mind is vitiated by this vanity of establishing a doctrine on facts, is too easily seen here. As Du Hamel believed that the periosteum deposited successive layers, which were added to the bone, it was his business to prove that the successive layers would be deposited alternately red, white, and red again, by giving a young ani- mal madder, withholding it for a little w hile, and then begin- ning again to give it. Now, it is easy to foresee that this tinging of the lamellse should correspond with the successive times in which the periosteum is able to deposite the layers of its substance ; but Du Hamel very thoughtlessly makes his layers correspond only with the weeks or months in which his madder was given or withheld. It is easy to foresee also, that if madder be removed from the bones in a few days (which he himself has often told us,) then his first layer, viz. of red bone, could not have waited for his laver of white to Vot.. I. B 10 or THE FORMATION be laid above it, nor for a layer of red above that again, so as to enable him to show successive layers : and if madder can so penetrate, as to tinge all the bone's that are already formed, then, though there might be first a ..ingsd bone, then a white and colourless laver, whenever he exceeded to give madder for tinging a third layer, it would pervade all the bone, tinge the layer below, and'reduce the whole to one tint. If a bone were thus to increase by layers, thick enough to be visible, and of a distinct tint ; and if such layers were to be continually accumulated upon each other every week, what kind of a bone should this grow to ? Yet such is the fascinating nature of a theory, that" Du Hamel, unmindful of any interruptions like thesej describes boldly his successive layers ; carrying us through regular details, experiment after experiment, till at last he brings up his report to the amount of five successive layers, viz. two red layers, and three white ones : nay, in one experiment he makes the tinge of the madder continue in the bones for six months, forming successive layers of red and white -, although, in an earlier experiment (which he must have forgotten in his hurry,) he tells us, that by looking through the transparent part of a cock's wing, he had seen the tinge of the madder gradually leave the bones in a few days. These experiments are as gross and palpable as the occa- sion of them ; and should stand as a warning to us, showing how severely and honestly we ought to question our own judgment, when we aim at confirming our preconceived theo- ries by experiments and facts. Yet by these experiments with madder, one most important fact is proved to us ; that the arteries and absorbents, acting in concert, alternately deposite and reabsorb the earthy parti-' cles, as fast as can be conceived of the soft parts, or even of the most moveable and fluctuating humours of the body. The absorption of the hardest bones is proved by daily obser- vation. When a carious bone disappears before the integu- ments are opened ; when a tumour, pressing upon a bone de- stroys it ; when an aneurism of the temporal artery destroys the skull ; when an aneurism of the heart beats open the tho- rax, destroying the sternum and ribs; when an aneurism of the ham destroys the thigh-bone, tibia, and joint of the knee - when a tumour coming from within the head, forces its way- through the bones of the skull;—in all these cases, since the hone cannot be annihilated, what can happen, but that it must be absorbed and conveyed away ? If we should need any- stronger proofs than these, we have mollities ossium ; a dis- ease by which, in a few months^ the bony system is entirely AND GROWTH OF BONES. H broken up, and conveyed away, by a high action of the ab- sorbents, with continual and deep-seated pain, a discharge of the earthy matter by the urine, and a gradual softening of the bones, so that they bend under the weight of the body ; the heels are turned up behind the head ; the spine becomes crook- ed ; the pelvis distorted; the breast is crushed anci bent in ; and the functions beginning to fall low, the patient, after a slow hectic fever, long and much suffering of pain and misery, expires ; with all the bones distorted in a shocking degree ; gelatinous, or nearly so, robbed of all their earthy parts; and so thoroughly softened that they may be cut writh the knife. Thus every bone has, like the soft parts, its arteries, veins, and absorbent vessels. And every bone has its nerves too : we see them entering into its substance in small threads, as on the surfaces of the frontal and parietal bones; we see them entering for particular purposes, by a large and peculiar hole, as the nerves which go into the jaws to reach the teeth: we find delicate nerves going into each bone along with its nutri- tious vessels ; and yet we dare hardly believe the demonstra- tion, since bones seem quite insensible and dead. We have no pain when the periosteum is rasped and scraped from a bone : we have no feeling when bones are cut in amputation ; or when, in a broken limb, we cut off with pincers the pro- truding end of a bone ; we feel no pain when a bone is tre- panned, or when caustics are applied to it; and it has been always known, that the heated irons which the old surgeons used so much, made no other impression upon the bone than to excite a particular titillation and heat, rather pleasant than painful, running along the course of the bone. But there is a deception in all this. A bone may be exquisitely sensible, and yet give no pain; a paradox which is very easily explain- ed. A bone may feel acutely, and yet not send its sensation to the brain. It is not fit that parts should in this sense feel, which are so continually exposed to shocks and blows, and all the accidents of life; which have to suffer all the motions which the other parts require. In this sense, the bones, the cartilages, ligaments, bursse, and all the parts that relate to joints, are quite insensible and dead. A bone does not feel, or its feelings are not conveyed to the brain ; but with this single exception, it shows every mark of life. Scrape a bone, and its vessels bleed ; cut or bore a bone, and its granulations sprout up ; break a bone, and it heals ; or cut a piece of it away, and more bone will be readily produced; hurt it in any way, and it inflames ; burn it, and it dies : take any proof of sensibility, but the mere feeling of pain, and it will answer u OF THE FORMATION to the proof. In short, these parts have a sensibility which belongs to themselves, but have no feelings in correspondence with the general system. A bone feels stimuli, and is excited to re-act; injuries pro- duce inflammation in the bones, as in the soft parts ; and then swelling a*.d spongy looseness, and a fullness of blood, sup- puration, ulcer, and the death and discharge of the diseased bone ensue. When the texture of a bone is thus loosened by inflammation, its feeling is roused ; and the hidden sensibili- ty of the bone rises up like a new property of its nature : and as the eye, the skin, and all feeling parts, have their sensibili- ty increased by disease, the bones, ligaments, bursas, and all the parts whose feeling, during health, is obscure and hardly known, are roused to a degree of sensibility far surpassing the soft parts. The wound of a joint is indeed less painlul at first, but when the inflammation comes, its sensibility is rais- ed to a dreadful degree : the patient cries out with anguish. No pains are equal to those which belong to the bones and joints. Thus ossification is a process of a truly animal nature : no coagulation will harden cartilage into bone ; no change of con- sistency will convert the blood into it; no condensation of the periosteum can assimilate it to the nature of a bone. Bone is not the inorganic concrete which it was once supposed; but it is a regularly organized part, whose form subsists from the first ; and which is perfected by its secreting arteries, balan- ced, as in every secretion, by the absorbents of the part : it lives, grows and feels; is liable to accidents, and subject to disease. It is a process which, at first, appears so rapid, that we should expect it to be soon complete ; but it becomes in the end a slow and difficult process. It is rapid at first; it advances slowly after birth; it is not completed in the human body till the twentieth year ; it is forwarded by health and strength, retarded by weakness and disease. In scrofula it is imperfect; and so children become rickety, the bones soften- ing and swelling at their heads, and bending under the weight of the body. And why should we be surprised, that careless- ness of food or clothing, bad air, or languid health, should cause that dreadful disease, when more or less heat, during the incubation of a chick, affects the growth of its bones- when the sickness of a creature, during our experiments, pro- tracts the growth of callus ; when, in the accidents of preg- nancy, of profuse suppuration, or of languid health, the knit- ting of broken bones is delayed, or wholly prevented. This process, so difficult and slow, is assisted by every pro- vision of nature. The progress of the whole is slow, that as, AND GROWTH OF BONE8. 13 long as the body increases in stature, the bones also may grow ; but it is assisted in the individual parts, where some are slow ; some rapid in their growth ; some delayed, as the heads of joints, that their bones may be allowed to extend; and others hastened, as the pelvis, that they may acquire their perfect size early in life. Ossification is assisted by the soft- ness of the cartilaginous bed in which the bone is formed ; by those large and permeable vessels which carry easily the gross- er parts of the blood ; by a quick and powerful absorption, which all along is modelling the bone; and, most of all, by being formed in detached points, multiplied and crowded to- gether, wherever much bone is required. There is one central ring first ossified in a long bone, as of the leg or arm ; the heads or ends of the bone are at first mere cartilage, but they also soon begin to ossify ; the body stretch- es in a radiated form towards either head ; the heads ossifying each in its centre, also stretch towards the bone ; the heads meet the body, and join to it; a thin cartilage only is inter- posed, which grows gradually thinner till the twentieth year, and then disappears ; the body, heads, and processes, becom- ing one bone. In flat bones, as in the skull, ossification goes from one or more central points, and the radiated fibres meet the radii of other ossifying points, or the edges of the next bone. The thick round bones which form the wrist and foot, have one ossification in their centre, which is bounded by car- tilage all round. The processes are often distinct ossifications joined to the bones, like their heads, and slowly consolidated with them into firm bones.* While the bone is forming, various parts, essential to its system, gradually rise into view. At first, we cannot in the long bone perceive any heads, processes, cavities, or cells ; these parts are very slowly formed, and are perfected only in the adult bone. At first, the whole length of a long bone is represented by a transparent gelly ; where there is no distinction of heads nor processes, it is all of one mass. After the red blood has be- gun to tinge this cartilage, the ossification begins, and one ring is formed in the middle of the bone : from this ring, the fibres stretch towards either end, and stop there ; then it begins to appear that the heads and body are distinct parts ; the fibres of the growing bone have extended till the cartilage is annihi- lated, and only a small plate remains, separating the knobs of the heads from the long body of the bone. Thus, there is no distinction betwixt the heads and the body, while the bone is * The processes and heads are named the epiphysis and apophysis of bones. 14 OF THE FORMATION cartilaginous ; they begin to appear, as distinct parts, at that stage in which the body of the bone is ossified, and each of the heads is beginning'to form : they continue three distinct bones, during all the early part of life, and are easily separa- ted, by soaking the bone in water ; when they are separated, there is seen a rough hollow on the surface of the epiphysis, or separated head, and a rough convexity on the end of the body : they are finally united into one bone, about the twen- tieth year. In the original cartilage, there is no hollow, nor cavity ; it is all one solid mass. When the ossification first appears, the cavity of the bone also begins, and extends with the ossifica- tion. At first, the cavity is confined chiefly to the middle of the bone, and extends very slowly towards the ends. This cavity, in the centre of the bone, is at first smooth, covered by an internal membrane, containing the trunks and branch- ings of the nutritious vessels, which enter by a great hole, in the middle of the bone ; and the cavity is traversed, with divisions of its lining membrane, which, like a net-work of partitions, conduct its branches to all parts of the internal surface of the bone ; and its nets, or meshes, are filled with a reddish and serous fluid, in the young bone, but secrete and contain a perfect marrow in the adult bone. The whole substance of a bone is not only fibrous, as ap- pears outwardly, but is truly lamellated, consisting of many distinct and delicate plates of bone ; which lie over each other in regular order, and might suggest the notion that successive ossifications of the periosteum form the bone. These lamel- la?, or plates, are more condensed and firmer towards the outer surface ; and are more loose, separate, and spongy, towards the internal surface of the bone : and it is easily seen, during the growth of a young bone, that the inner and more delicate plates are separating from the walls of the bone, and receding towards its cavity ; and these plates, being again crossed by small bony partitions, form a net-work, or spongy mass which fills the whole cavity of the bone. In the middle of the bone the cavity is small, the walls are thick, and have all their bony plates ; the cells of net-work are few, and large : but towards the ends, the bone swells out; the cavity also is large but it is not like that in the middle, a large tubular cavity ; it is so crossed with lattice-work, with small interstices and cells that it seems all one spongy mass of bone; and so many of thr- inner layers are separated, to form this profusion of cells that she whole substance of the bone has degenerated into this AND GROWTH OF BONES. 15 lattice-work, leaving only a thin outward shell.* This reti- cular form is what anatomists call the cancelli, lattice-work, net-work, or alveolar part of the bone : it is lined throughout with one delicate membrane ; and inward partitions of the same lining membrane cover each division of the lattice-work, forming each cell into a distinct cavity. In these cavities or cells the marrow is secreted. The secretion is thin and bloody in children ; it thickens as we advance in years ; it is a solid oil, or marrow, in the adult. The marrow is firmer, and more perfect in the middle of the bone ; more thin and serous to- wards the spongy ends. The whole mass, when shaken out of the bone, is like a bunch of grapes, each hanging by its stalk. The globules, when seen with the microscope, are neat, round, and white, seeming like small pearls, and each stalk is seen to be a small artery, which comes along the mem- brane of the cancelli, spreads its branches beautifully on the surface of the bag, and serves to secrete the marrow, each small twig of artery filling its peculiar cell. To this, an old anatomist added, that they had their contractile power, like the urinary bladder, for expelling their contents ; that they squeezed their marrow, by channels of communication, through and among the bony layers ; and that their oil exuded into the joint, by nearly the same mechanism by which it got into the substance of the bone. While the constitution of a bone was not at all understood, anatomists noted with particular care, every trifling peculiari- ty, in the forms or connections of its parts, and these lamellae attracted particular notice. That a bone is formed in succes- sive plates, is easily seen, as in whalebone ; or in the horns and bones of the larger animals; in church-yard bones, which have been long buried, or long exposed to the air. It is de- monstrated by a careful picking, and separation of the scales, in a young bone, or by burning a bone, which melts and con- sumes its gelly, and leaves the bony parts entire. It is seen in the common diseases of bones ; for they cast off by successive plates, or leaves, whence the process is named exfoliation ; and one plate is thoroughly spoiled and cast off, whilst another is entire, and sound. Malpighi had first observed the lamel- lated structure of bones, likening them to the leaves of a book. Gagliardi, who, like Hippocrates, went among the burial pla- * That it is merely an expansion of the layers that forms the cancelli, and a mere swelling and sponginess of the same quantity of bony substance, that makes the ends so much thicker thin the middle, is proved hy this, that an inch of the smaller bony tube, cut from the middle, weighs equally with an inch ot the large spongy tube, cut out from the ends. i6 OF THE FORMATION ces of the city, to observe the bones there, found in a tomb.) where the bones had been long exposed, a skull, the os frontis of which he could dissect into many layers, with the point ot a pin. He afterwards found various bones, from all parts of the bodv, thus decomposed ; and he added to the doctrine ot plates, that thev were held together by minute processes, which going from plate to plate, performed the offices of nails : these appeared to his imagination to be of four kinds, straight and inclined nails, crooked or hook-like, and some with small round heads, of the forms of bolts or pins.* Another notable discover)-, was the use of the holes which are very easily seen through the substance of bones, and among their plates. They are, indeed, no more than the channels by which the vessels pass into the bones ; but the older anatomists imagine them to be still more important, allowing the marrow to transude through all the substance of the bone, and keep it soft. Now this notion, of lubricating the earthy parts of a bone, like the common talk about fomen- tations to the internal parts of the body, is very mechanical, and very ignorant; for the internal parts of the body, are both hot and moist of themselves, and neither heat nor mois- ture can reach them from without: the bone is already fully watered with arteries ; it is moist in itself, and cannot be fur- ther moistened nor lubricated, unless by a fuller and quicker circulation of its blood. It must be preserved by that mois- ture alone which exists in its substance, and must depend for its consistence upon its own constitution ; upon the due mix- ing up of its gluten and earth. Kvery part is preserved in its due consistence by the vessels which form its subsistence ; and I should no more suppose fat necessary for preserving the moistness of a bone, than for preventing brittleness in the eye* This marrow is, perhaps, more an accidental deposition, than we at first sight believe. We indeed find in it such a regulari- ty of structure, as seems to indicate some very particular use- but we find exactly the same structure in the common fat of the body. When, as we advance in years, more fat is depo- sited in the omentum^ or round the heart, we cannot entertain the absurd notion of fat being needed in our old age, to lubri- cate the bowels or the heart; no more is the marrow (which is not found in the child,) accumulating in old age for prevent- ing brittleness of the bones. * These nails, which Gagliardi imagined, were no more than the little ir- regularities, rifirgs, and hollows of the adjoining plates, by which thev are connected. AND GROWTH OF BONES, it The blood vessels of a bone are large, in proportion to the mass of the bone: for first one great trunk enters commonly about the middle of the bone, as in the thigh-bone, leg or arm, and is called the nutritious or medullary artery ; it pene- trates into the central cavity of the bone, spreads upwards and downwards, supplying all the substance of the bone itself, and giving those delicate arteries which secrete the marrow. Other arteries enter from without, at the spongy ends of the bones, where the holes are not visible only, but very large in the adult; particularly large arteries enter into the heads of the bones, as of the shoulder, or of the thigh-bones ; and there the periosteum adheres very strongly: and every where on its surface the bone is supplied by numerous vessels from the periosteum (and this seems, indeed, to be the chief use of that membrane ;) so that in tearing off the periosteum, the surfaces of the membrane, and of the bone, are seen covered with bloody points ; all the vessels are conducted to the sub- stance of the bone by its two membranes: the internal vessels by the membrane which lines the cavity, and which is known by the absurd name of internal periosteum ; the external one by the outer membrane, the proper or external periosteum. The internal periosteum is that membrane which surrounds the marrow, and in the bags of which the marrow is formed and contained. It is more connected with the fat than with the bone ; and in animals, can be drawn out entire from the cavity of the bone: but its chief use is to conduct the vessels which are to enter into the substance of the bone; and this connection and office is so essential to the life and health of the bone, that the spina ventosa, or scrophulous bone, is merely a failure of the internal circulation, a total corruption of the marrow, and a consequent loss of the medullary vessels; by which the whole bone dies, is thrown out by nature, or more- frequently the limb must be cut off. The same effect is pro- duced in our experiments, where, by piercing into the medul- lary cavity, and destroying the marrow, the shaft of the bone dies, while the heads and processes live, merely because they are supplied more fully by their external vessels. The periosteum, which was once referred to the dura mater, is merely condensed cellular substance; of which kind of matter we now trace many varied forms and uses ; for, so close is the connection of the periosteum, tendons, ligaments, fasciae, and bursae, and so much are these parts alike in their nature and properties, that we rt ckon them but as varied forms of one common substance, serving for various uses in different parts. The periosteum consists of many layers, accumulated andcondensedc.no above another: it adheres to the bodv of Vol. I. C id OF THE FORMATION the bone by small points or processes, which dive into the* substance of the outer layer, giving a firm adhesion to it, so that it may bear the pulling of the great tendons, which are fixed rather into the periosteum, than into the bone.* It is also connected with the bone, by innumerable vessels. It is not in itself vascular; but it is the medium by which vessels are transmitted to the bone ; and our injections do not easily colour the periosteum itself, while they make the bone which belongs to it thoroughly red. The layers of the periosteum nearest to the bone, are condensed and strong, and take a strong adhesion to the bone, that the vessels may be transmit- ted safely, and the fibres of this inner layer follow the longi- tudinal directions of the bony fibres. The periosteum is looser in its texture outwardly, where it is reticulated and lax, chang- ing imperceptibly into the common cellular substance. There the fibres of the periosteum assume the directions of the mus- cles, tendons, or other parts which run over it. The office of the periosteum is not to generate bone ; and therefore it ad- heres but slightly to the growing bone : it is to nourish the ex- ternal plates ; and therefore as the bone grows, and as the ex- ternal plates are further removed from the medullary vessels, the adhesion of the periosteum becomes closer, its arteries are enlarged, and the dependence of the outer layers on the periosteum is as well proved as the dependence of the body of the bone upon its medullary artery; for as piercing the me- dulla kills the whole bone, hurting the periosteum kills the outer layers of the bone. Any accident which robs the bone of its periosteum has this effect; accidental wounds of the periosteum, deep ulcers of the soft parts, as on the shin, the beating of aneurisms, the growth of tumours, the pressure eren of any external body, will, by hurting the periosteum, cause exfoliation, which is, in plain terms the death of the external layer, by the injury of the outward vessels; and an active inflammation of the deeper layers, which being fully- nourished by the internal arteries, inflame, swell, become porous and spongy-, form granulations, and these granulations push off the mortified plate, and form themselves into new bone, which supplies its place. "The cartilages are also part of the living system of the bone: and we see too well, in the question of the' bones them- selves, how unphilosophical it must be, to deny organization and feeling to any part of the living body, however dead or * It would appear that the arteries are convertible through time into th»fc tooth-like proceffes, by which the periofteum is fixed into the bore ; for in ymith the veffels are numerous, the adhefion slight, and the ftparation bloody • but' '• tile older fubject, the feparation is more difficult, and lefs blood is feen. AND GROWTH OF BONES. 19 insulated it may appear ; for every part has its degree of life : the eye, the skin, the flesh, the tendons, and the bones, have successive degrees of feeling and circulation. We see, that where even the lowest of these, the bone, is deprived of its small portion of life, it becomes a foreign body, and is thrown off from the healthy parts, as a gangrened limb is separac.d from the sound body; and we speak as familiarly of the death of a bone, as of the gangrene of soft parts. How, then, should we deny drganization and life to the cartilages, though surely, in respect of feeling, they must stand in the very last degree ? The periosteum goes from the bone over the surface of the cartilage also, where it is named perichondrium : it still pre- serves its own vascular nature ; the vessels can be injected ; and it is not to be believed that the perichondrium has these vessels,, without communicating them to the cartilage to which it belongs. We pee red arteries in the centre of an ossifying cartilage ; and therefore we know that the trunk of the artery may be red, as in the ossifying part of the cartilage, and yet the extremity of the same artery be pellucid, as in the unossi- fied part. Since vessels run through the cartilage to generate bone, we cannot, in reason, suppose that these vessels are produced in the instant in which they appear : they had exist- ed before ; they are but dilated now: the increasing action dilates them, and the dilatation makes them red : this enables them to secrete bone, and, in many cases, as in the acciden- tal joint formed by a fracture ill cared for, we can, by paring the cartilage, set the vessels free again, and make them begin to secrete. Wherever we find a vascular membrane surrounding and nourishing any part, as the vitreous or crystalline humours in the eye, we must not suppose that such are insulated parts, maintained there by mere adhesion; but must consider them as parts regularly organized, their vascular membrane being part of their living system ; and though the transparent hu- mours of the eye, the cartilages and ligaments over all the body, and all the system of the bones, have been considered as mere concretes, and insulated parts, they are now known to be regular parts of the living whole. The cartilages have no very active circulation ; it is such as to keep them in life, but not so active as to endanger inflammation ; in the continual shocks which they must endure, their feeling must be very ob- scure ; for feeling also would have been inconsistent with their offices, which is to cover and defend the bones; to yield to the weight of the body, and to restore themselves when that weight is removed ; to bear all the shocks of leaps or falls; t