ESSAY - ORIGIN, PROGRESS AND TREATMENT OP CHO L E II.A, WITH REMARKS ON BERRIBERRI. AND DIET, AS CONNECTED WITH ENDEMICS AND EPIDEMICS. I BY JAMES BANKIER, JV^D. o. OF THE ROYAL NAVVy J/j a »^ a ;^g;om MADRAS: PRINTED AND PUBLISHED J. B. PHAROAH. MDCCCXXXV. To JAMES ANNESLEY, Esquire MEMBER OF THE MADRAS MEDICAL BOARD AS A TRIBUTE ot RESPECT FOR HIS GENIUS, AND GRATITUDE FOR HIS ASSISTANCE » THE FOLLOWING ESSAY IS INSCRIBED THE AUTHOR. * i • » i • ; PREFACE. In committing the following ESSAY — the result of considerable experience, and mature reflection — to the judgment of the PUBLIC, the AUTHOR has little to offer. He is aware of its many imperfections, as regards style ; and feels, moreover, that he may be justly charged with prolixity. His chief aim has been to render his views intelligible ; and, if' he has succeeded in doing so, he will be quite satisfied to forego all claim to elegance. He considers it a hopeless task to attempt to disarm the hostility of criticism ; but, in justice to himself, he must explain that the work has been prepared under the great disadvantages to which almost all Assistant Surgeons in The Navy are subjected, — both as regards Books of reference, and opportunity for undisturbed meditation. If this produces no effect on the mind of the professional critic, it may obtain, at the hand of his other PREFACE. Medical brethren, some slight indulgence, for many minor errors, which, he blows are scattered over the following pages. lie must also avail himself of the present opportunity to acknowledge his great obligations to Mr. J. SriVEN, Assistant Surgeon in the Renal Navy, for many valuable suggestions and remarks, during the preparation of the work. CONTENTS. CHOLERA. Chap. Page I. — Conservative Principle 1 II. — Sympathies 7 111. — Animal Heat 14 IV. — The Blood avd Secretions ». . . 41 V. — The Brain and Nervous Siistem. ....... 57 *J VI. — Marsh Miasm, with other noxious exhalations, as existing in the atmosphere. ... 68 Vll.— Contagion 147 VIII. — Inflammation and concussed Brain said to be a cause of Cholera 169 IX. — Tetanus and Cholera compared 179 X. — Symptoms 190 XI. — Treatment 244 Section I. — Blood-letting 254 II. — Opium 309 lll.— Calomel 329 IV. — Stimulants 333 Cantharides Epispastics Warm Bath Acids Purgatives Rubcfacients 382 Drink 383 Emetics 38(3 Cantharides 390 Phosphorous 393 Conclusion . 396 BERRIBERRL Page. Chap, I. — Symptoms, Bfc ? 409 II. — Treatment 424 111. — Diet as connected with the produc- tion of Epidemic Diseases 436 CONTENTS. INTRODUCTION. X HE importance, and real value, of the acquisition of new Territories, affording- scope or attraction to the Natives of Great Britain, must on sober reflection be regarded as depending", in a very high degree, on the diseases which are to be encountered, in contrast with the power or wealth which is to be acquired. Viewed in this light the Physician, equally with the political economist, will find the regions of India an extensive and interesting field of observation ; and although the latter might conclude his labours, by arguing the expediency of preventing our population from proceeding in such numbers to a land in which so many have been cut off, chiefly by one of the diseases to which all in that climate are subject ; yet the former, instead of resting here, will remember that it is not his own country alone, or the health and happiness of his own countrymen merely, which are to engross, or terminate his exertions, but that his species generally, without regard to locality and the ailments which ' human flesh is heir to" in their causes, amelioration, 2 and possible cure, demand from him researches which must be extended far beyond that limit, and of such a nature as will display a utility, and stamp a dignity and benevolence upon his profession, equal, if not superior, to any that can be claimed by any other human science, or pursuit. Sir Gilbert Blanc observes, in the introductory remarks to his Medical Logic, that the production is the " fruits of more than fifty years meditation and experience."— What an enchanting prospect this holds out for any one undertaking the study of Medicine. Our Author, too, was of deep research and practical knowledge, in his own profession, and inferior to few in general attainments. How humiliating it is to think, that so little, of what some may be inclined to call true knowledge, can be acquired in such a space of time. It would be injustice, however, for any one to imagine that the instructions contained in the Logic, could not be acquired now a days in an incredibly shorter period, by an enterprising, industrious, and ingenious mind. Iby no means wish to cast any reflection, were it possible, on Sir Gilbert ; for, we know that in the more early part of his career, Medicine had not entirely escaped from the deep mist of superstition, and ignorance in which it was enveloped. Man was then but too apt to arrogate to himself principles, which, when properly explained could not be held tenable for a moment. In 3 the present day things are a little altered, — comparatively clear, however, as the atmosphere is, in which medical laws are now placed, it is even yet sufficiently obscure to obstruct our mental vision ; — the darkness may be truly considered as but half cleared away, and by no means unfolding- the meridian splendours of certain knowledge. There is one point which w T e of the present day may be proud of, and it must be confessed that it would be a shame were it otherwise — we are better acquainted with the principles of the healing art than the antients. But, even admitting this, we have no great reason to boast ; we must remember that we are only the dwarf on the giant's shoulders ; although, when so placed, we can see somewhat farther than he, yet he is the structure which upholds us, or more properly the foundation on which we have built. This truism consists in the fact — that the ancients collected all their observations of disease from their own habitatio — nature — in so far as related to the actual statement of things present. It is therefore in the statement of symptoms that we may expect them to be most accurate, and those who attentively peruse their works (as every Physician ought) will find them so. The diseases which they detail are generally all strictly correct ; any others, although they may approach near to them, if they do not mention every characteristic feature in the complaint, must be an alteration of that, or 4 this disease, from what it was in their day. Cholera, as it shews itself in its Epedemic form in India, must either therefore be a higher caste of disease, which they witnessed so seldom as to allow it to pass unnoticed, or it must be a new one added to our catalogue. Many may be inclined to believe both positions correct, but most of the present time, it is presumed, will hold to the latter opinion. It would be unreasonable in the extreme to imagine that our forefathers could be as successful in their treatment as we are. The reason of this may at once appear when we take into consideration the paucity of means falling to their share ; so much so indeed was this the case, as to preclude the idea entirely ; while, from a contrary cause, it might be truly said of us that we ought to be at the acme of it, as being in possession of such a store of chemical knowledge, as well as an intimate acquaintance with those parts of the Globe, which supply drugs of the most important and valuable nature. Yet, even with all this boasted knowledge, how lamentably deficient are we in the treatment of many diseases of a fierce endemic and epidemic nature. In fine then we may compare the antients, to a simple substance, and ourselves to a quadruple or even sextuple, if we attempted more it would be found of but little avail, for, although placed on the top of the highest mountain, and with the best eyes, in the most serene day, we could not see round the world, or explain 5 every thing in it. From the above it may be concluded, that any one endeavouring to scan the whole secrets of nature, must ultimately terminate his efforts in disappointment, if not exhaustion of body and mind. Sir Gilbert need not be ashamed, and I am confident he is not, when he acknowledges that his " fifty years meditation and experience" have not enabled him to discover the whole governing laws of the medical world ; more particularly when it is remembered that the united efforts of all the medical profession either in, or out of India, have as yet done but little in clearing away the mists, or elucidating the cause or causes, the proper treatment, or even satisfactorily pointed out the reason of failure, which so often occurs in the case of Cholera alone. The cause or causes of this, as well as of many other diseases, have hitherto remained wrapt up in much obscurity, and it is likely that this migrht continue to be the case for ages to come, did we not apply those laws and phenomena, with other circumstances of which we are in possession to their elucidation. In a task of such magnitude and under all considerations it becomes me to be circumspect, at all events very modest in giving any opinion considering that it has yet, as I have already intimated, bid defiance to the efforts of the whole medical profession. In the prosecution of the enquiry, I may be as unsucessful as those who have gone before 6 me, but the very magnitude and difficulty of the subject have stimulated me to the undertaking-, and, if I fail, may plead somewhat on my behalf, my attempt in that case will only like those of my predecessors fall into oblivion, or be remembered on account of the illustrations, or opinions advanced. Labouring under the vast load of difficulties which to attend an Assistant Surgeon's life on board a Man-of-War, — in particular as regards a defect of books of reference, I have been compelled to form my own opinions on the subject. This so far from being a defect many may say is the very point they wanted : while others will be inclined to suppose that in these circumstances nothing of importance can be expected. It does not become me to say anything in extenuation. In the investigation of the various phenomena, I shall commence by accounting for some of those which pervade the whole of the animal creation. As to the treatment, it is to be hoped, there will be shewn evident proofs of our failure, and that this will continue to be the case either in consequence of an improper administration of our remedies, or in consequence of a want of remedies endowed with properties, which none in the pharmacopeia at present appear to possess, at least so far as we are acquainted with their various combinations and actions upon the living body. In short then it is proposed in the following pages to enter as minutely as circumstances 7 will permit into every point connected with the rise, progress and treatment of the disease. If anything" of importance has escaped observation, it is to be hoped that it may be speedily supplied by the observation of others ; so that this pestilence may at length be removed from the number of those which form the opprobria medicorum. It is erroneous to suppose that any disease admits only of one method of cure ; those who think so, can know but little of the principles of medicine. The Cholera is one, which is so very versatile in its character, as perhaps to admit of as many modifications of treatment, as the habits of the patients are various. CHAP. I. CONSERVATIVE PRINCIPLE. By the term is to be understood that power which living bodies possess of resisting putrefaction for a time, or as Mr. J. Hunter expresses it "the living principle." Many no doubt will be astonished in what manner this can be applicable to the disease in question. The answer is short, my opinion being that it is the living principle which is assailed. I shall, therefore, proceed to the point by considering in what function of the body the conservative power chiefly resides. I observe that dead animal matter becomes most readily putrid at the temperature of 86° to 100° of Fahrenheit ; I would therefore be inclined to say that if this principle of resisting putrefaction is to be given to any one set of the functions of the body, it ought to be placed in the nervous, this, however, at present may appear perhaps saying a little too much; but that it depends on this in combination with a due distribution of uncontaminated blood there can be but little doubt. There are instances in the animal world in which the circulation of the blood can be suspended for a considerable time ; and, when again placed under favourable circumstances, the dormant animal resumes its usual avocations ; such happens in the case of the frog and of some other cold blooded animals. But in warm blooded animali, and particularly in man this never occurs, since we see in cases in which the circulation is impeded, as in old age, how quickly the extreme parts of the body become gangrenous, 'ibis however may depend, as I shall afterwards state, on a deficit of the blood., producing a diminution of action in the nerves, and 2 in such rases we cannot expert that a due performance of vitality in the system, or the parts affected, should be kept going on. I observe then, that in dormant animals, or reptiles in which there is no circulation, or, at least, in such an inconsiderable degree, as not to be admitted in evidence, that the principle of resistance is in existence. To what can we ascribe this pow er, independent of the cold medium in which they may be placed; surely to none other but their nervous system, these examples however are only brought forward as a helping illustration; we do not admit that such laws can be properly applied to man, for here we will find that these two functions are inseperably connected; v hen one of them is deficient the other suffers to the extent of the lesion inflicted, and then the part itself, or, this last may be the medium through which the disparity of action is communicated. The conservative principle in man, cannot therefore be looked on as the result of any one action, but must depend on them all in some degree. The body has a constant and arduous struggle to maintain against putrefaction, where such changes in the thermometer exist as above noticed. This power of resistance, it will be admitted, cannot be present in any one animal substance, unless it is endowed to a certain extent with the principles of life; — according as life is evident, either in a major or minor degree, so will the strength of the conservative power be. As applied to warm blooded animals, those that feel most, have it in the greatest perfection. I would therefore place it in that function which is possessed of the sentient faculty. We might adduce cases of small pox, or other diseases generally called putrid, to prove that such depend on an abstraction of the circulation from the parts, this term however may by some be deemed inadmissable in a certain degre°, for where the principles of life are still in existence, 3 there can be nothing actually putrefactive present, although there may be an approach to it, the above being present there also will be found an analogous resisting power. On the other hand as we descend the scale of animal existence, do we not find that the putrefactive process commences much more readily in those in which there is a weak nervous power, than in others possessed of a high one, this is more evidently the case under the changes of the atmosphere already noticed. I shall make a fewobservations on some of the above remarks as points of illustration. Let us take the case of small pox with extreme feetor; the parts from which the oifensive smell proceeds, although they may not be entirely deprived of their blood, yet have lost all feeling, and under these circumstances we have them in a demi- gangrenous state. These parts then may be said to suffer in consequence of their nervous supply being almost entirely withdrawn or destroyed, there is always a strong tendency in such cases, when they terminate fatally, of the body running hurriedly to putrefaction, more so than is to be met with in other instances of death, particularly when such occur suddenly. To shew that the principle of resistance is much more durable in those cases of deaths from wounds and other accidents than it is in those from lingering disease we have only to notice hovy much longer the body of a person shot will resist the putrefactive process, than of one who has died of plague, &c. In the former we will find that putrefaction is long in shewing itself, whereas in the latter, as soon as life has become extinct, the process of decomposition takes place, and will proceed more rapidly than in the other ; and this too independently of what may be urged as to the putrefaction of the blood itself, which I do not admit in toto to be the 4 cause of it as will afterwards appear. Hence we draw the conclusion, that when the power of resistance has been strong during life, it will continue so, in a certain degree, after life has become extinct, as it has suffered no lesion, it will not he hurried on so quickly to putrefaction as in the other case in which, this function has been weakened by continued exertion during a severe and lingering illness. That this principle resides therefore in one of the functions of the body more than another I think will be granted, and that this particular one is the nervous may be as little disputed, since we observe putrefaction takes place more speedily in those cases in which this power is as it were, at once struck dead ; (as in deaths from lightning,) than in such as arise from blows or other mechanical injuries ; in these instances there is more time given for exhausting the power in question than in the former, and the reason is obvious the nervous power is here at once annihilated the blood also suffering in some degree. Many, no doubt, will object to the above mode of reasoning and say that the conservative principle more immediately resides in the blood, and they will bring forward examples of its obstruction in various parts of the body, to such an extent as to have produced gangrene. I answer that this very obstruction of blood impairs primarily and in a great degree the nervous energy of the part, then under such a condition of things, both must go down hill rapidly, as will afterwards be shewn. It may be gathered from the writings of Sir Gilbert Blanc, Mr. J. Hunter and other eminent men that they considered the conservative principle to reside mainly, if not entirely, in one function of the body, but were at a los« to say in which of the actions of life they would place it. The real deduction, however, is that it cannot be said to reside in any one action so far as regards man, and the 5 warm blooded animals, but that it depends on a due performance of them all ; few will dispute, so far as relates to a proper respiration, a free circulation of the blood and, above all, to an efficient maintenance of nervous play, which depends chiefly on a healthy state of these actions, as I shall endeavour to shew in the following pages, — that all the powers of the body are dominant to the laws of the nervous system. But, although this is highly probable, and as some may say, it even amounts to more than a probability, yet it is not sufficiently apparent, more especially when wo observe tha various forms of this conservative principle existing from the Zoophites and all the colder blooded animals, till we come to those of warm blood, and from them trace its increasing power up to man. We see it existing in such varied and seemingly inexplicable forms in vegetables, from the most insignificant plant to the largest tree, as to lead us to the belief that they also are endowed with a conservative principle, or as I would say a nervous power. Now the above is correct, I believe, and is the manner of reasoning adopted by most men on the subject. I will attempt to prove in support of the opinion given that they also are possessed of a nervous power, or at all events of something analogous to it, since it appears that each distinct class of animals or plants has a power of resistance in proportion as it possesses more or less of this conservative principle, and no matter whether it does not reside in the circulation of fluids, or whether it exists in a single or double circulation since, as I have said, those possessing the latter will be found to resist in proportion to it ; the laws which govern them however I again state are not strictly applicable to man. Have we not heard of fields of vegetables, corn, rice, &c. being blighted by the same cause as that producing pestilential diseases ? Have we not found in all classes of animals 6 that death depends upon the degree of susceptibility for receiving these impressions and this too at the very time that they are prevailing ? Do such instances not prove that there is one universal cause operating towards the destruction of this power ? As to animal and vegetable life becoming dormant for a certain stated time, still I say that although the juices are not circulating, they have a power of resistance, which is not entirely extinct ; for the time being, it may be dormant but this only in a certain degree. A tree in winter possesses some of this principle, and it only requires heat to be properly applied, with a certain state of the soil, to enable it to flourish even in that season. It is almost superfluous to observe that if the tree be cut off from communicating with the roots, it will to a certainty die ; lop the leg oiF a dormant frog and the portion soon loses the conservative power, even although there has been little or no circulation of fluid in either case. We see then that heat is of the greatest importance to such a state of life ; now it may be stated that in my opinion heat, as it exists in the human body, mainly depends on the nervous power, and I would be also inclined to place the conservative principle more immediately in the power capable of generating it; at the same time I admit that a due performance of the one cannot exist without a healthy action of them all. It may again be asked what has all this to do with Cholera? I answer briefly by adverting to some facts observed by Dr. Davy, in the Island of Ceylon, as regards this disease. There was a " flaccid nature of the muscles ;" such a state generally occurs from the speedy operation of some power capable of destroying the conservative principle, whether from the operation of an all-powerful and overwhelming cause, such as happens in those killed by lightning or in animals hunted to death ; in such instances the nervous power is 7 either destroyed or exhausted. v There was also a ten" derness of the muscular fibres as in many of the Bom" bay cases, there was no difference in the colour of the " arterial and venous blood, and no instance of a huffy " coat on the blood that was drawn ; which in reality " was so loose and uncoagulable that when- venesection " was necessary the vessels were opened with the great" est caution from the difficulty of restraining the blood " afterwards." If this does not prove that the conservative principle is extinguished Ido not know what does, therefore from the above reasoning and more particularly from what is yet to be advanced I am inclined to place the existence of this disease chiefly in the derangement of the nervous system. CHAP. 11. SYMPATHIES. (C Those who are disposed to depreciate the practical " value of anatomy might alledge that there are several " important functions, upon which the knowledge of the li structure of the dead body though ever so minute and " perfect could throw little or no light ; nay that there " are some morbid circumstances and indications in the " living body, ascertained by empirical observation, in " which mere anatomy is' more apt to mislead than in" struct." Our much respected author has stated facts so far as regards a traceable communication anatomically considered can point out. It does not, however, necessarily follow, although we cannot shew it by demonstration, that there is no such thing existing between the external and internal parts of the abdomen. There are many other parts of the body precisely under the same difficulties of illustration as respects disease, and 8 there are other points of anatomy where we cannot detect the manner in which things of the utmost importance are accomplished. We cannot for example anatomically demonstrate the absorbents of. the brain, although we are positive that fluids are removed from this part, as well as others, and it is no matter whether this takes place by nervous absorption or by the undetected absorbents themselves, T here principally allude to the opinions of the major portion of anatomists as to their non-presence. With respect to the surface of the body and the contained viscera, that there is a communication existing, although it cannot be traced between these parts, few of the present day will venture to deny and, although I do not adopt the Cullenian theory in full, concerning the smaller vessels, yet I am inclined to believe as I have stated in the remarks on Dysentery, that such a thing as sympathizing action does exist between the external surface of the abdomen and viscera, also, that this state of things has been mush overlooked by some medical men. In short then we must admit that there are such actions as sympathies in the human body ; by adopting these opinions we will be enabled to account in the most satisfactory manner for the nontraceable phenomena, the existence of which we may be as positive of asofour own. How can we otherwise explain the fact, that the skin is soon drenched with perspiration, after we have drank freely of cold water, when the body is hot, especially in intertropical countries. Upon the hypothesis it will immediately set a going all the minute vessels on the skin, and quicker than I can write the words, the surface will be drenched with perspiration j the liability to ihz annoyance wears off by length of residence, but it does not entirely leave us at any period. 9 How else but on the principles of sympathy are we to account for the relief which is obtained in many cases by a discriminating application to the skin of a blister, fomentations, or local blood-letting ; this too when applied over the region of the abdomen for the relief of the oppressed viscera, where there is as has been stated no traceable communication, not even of nervous power. The answer may be, it does not necessarily follow that there should be a distinct nervous junction in any, or every instance, in all portions of the body, to give that relief which the above remedies, when judiciously employed, are so well calculated to afford. We know that there exists in every part thereof, more especially of analogous textures, a disposition to sympathize with each other, hence it follows, that even if the smaller vessels, nerves, &c. which ramify in the skin, be relieved, that they also wall extend part of this, to the deeper portions, which are assailed ; this may be accomplished either through the medium of the sensorium commune or by a more direct influence on the abdomen itself, and in proportion to the benefit, the nerves, the other vessels, or the muscles here may have received. The tension of the abdomen being taken off, will operate beneficially on those parts below. But not to leave the subject in the conjectural state, which many might say belongs to it, I shall proceed by illustrating the manner in which fomentations act, in relieving inflammations of the viscera of the abdomen. I mention that they must be continued for some time, or until the more internal parts become heated, then we will find, independently of the external relaxation produced, that in proportion as heat has been communicated to these parts, the bowels, now begin to sympathize, and thus obtain a portion of the benefit which was previously 10 afforded to the surface. Besides we will perceive that these applications will in some measure equalize the balance of the broken circulation, and consequently take ofFthe stimulus of hulk in the blood vessels. The blood therefore circulating more freely on the surface than before, will leave less to be distributed to the more internal parts, and this is the manner in which a hot bath also gives reiiof. Care should be taken in some diseases as will afterwards be pointed oat, that we only continue this last so long as we find the stimulus from the heat to be attended with advantage, and the more particularly so when we do not want any thing like its sedative effects. Either from its improper application, as regards the stage of the disease, or its too long duration it will not only do no good but will assuredly be the means of sinking our patients beyond recovery. To prove that heat operates in the manner stated, it is only necessary to apply hot fomentations to the abdomen of a subject in the dissecting room for some time, on opening which we will find the internal viscera warm. This then is the true application of fomentations, and they should be continued for some time, so that they may produce the whole good which they are calculated to effect, provided no untoward circumstances of the patient's habits, or the nature or duration of the disease forbids the application of heat in any form. The benefit derived from blisters is soon stated, nature, or the laws governing the animal economy seem to be extremely averse to maintain in active operation two diseases, she will therefore divide her attention between them, thus in trial the more severe yields from having part of the onus taken off and transferred to the other. That this is in a great measure accomplished through the medium of nervous communication will 11 afterwards appear when I state my views with regard to inflammation, and point out their proper application. As to the operation of local blood letting, and I shall take that of leeches as the more simple, it a"ts not only by abstracting a portion of the stimulus of bulk from the system, but by doing so, it relieves the stimulus which distention gives to the nerves of the part, and thereby prevents a continuance of suffering from this cause. It must be observed that but little benefit will be derived from it, unless the tension of the abdomen, or other parts, be somewhat considerable, therefore they are either less important than general depletion, or more so, according to the nature of the inflamation and the parts attacked. By having recourse to any or all of the above remedies we render the abdomen more pliable, by relaxing it we give a more free play to the muscles and in this manner remove the stimulus of distention from the viscera, just as we would cut through a fascia in order to give exit to the fluid beneath, which has been the occasion of great excitement, thus we will almost immediately relieve the system. Now let us look to another part of the subject, and observe in what manner relief is afforded by these remedies in such cases as pleurisy. I have already noticed the general principles which ought to guide us in their application, it is therefore only requisite to bear in mind that local blood-letting affords relief by v the abstraction of part of the bulk of the general stimulant, the blood thus giving ease to the nervous system, andsecondly byallowingamore free play to the muscular power of the ribs. We must always recollect that every part of the body by means of its nervous power will, and does to a certainty sympathize, with another and distant part, thus we see that man is M fearfully and wonderfully made/ for when 12 relief is given to any part its effect pervades the whole chain of vessels connecting those most distant from it ; either propagated to them from the sensorium commune, or, by the direct action of the nervous branches themselves, independently of any assistance from the brain, or medulla spinalis, since we see that the benefit afforded does not require to travel the rounds of the system, as from the extremity of the nervous power to its origin, or from thence again to its extremity. The sympathetic nerve and its ganglia have a wonderful effect in accomplishing this ; they obviate the necessity of many such impressions travelling so far as the brain and thereby prevent an immediate disturbance which might otherwise have occurred, bat by doing so they may fix disease amongst the viscera of a certain kind. The ganglionic plexuses may be considered as another brain placed in the thorax and abdomen, possessing a regulating or harmonizing action, supplying deficiencies, or quelling disturbances, when there are either too great or too little impressions made on these parts. There are three different sympathies existing in the body by which diseases can be communicated or alleviate — 1 . sympathy of communication — 2. association — 3. equilibrium. 1. The sympathy of communication is that in which one part diseased will communicate disordered action to another and distant part of the body or the adjoining texture, from which we may have the same sort of action or another species of disease induced. 2. Sympathy of association, is when two distant organs are simultaneously affected; I give a familiar example; the tickling of the fauces with a feather will in most instances produce vomiting, this takes place from the sympathy that exists between the upper end of the canal and 13 stomach, the action thereby induced causes contraction of that viscus, and this aided by the diaphragm, causes the discharge of the contents. 3. Sympathy of equilibrium. Thus the action of a blister in phthisis pulmonalis does good, and its beneficial operation can only be. explained on the principle of equilibrium, causing pain on the surface, this of course balances that below. It is worthy of remark that many severe diarrhoeas of children are caused by the nervous sympathy which exists between the head and bowels ; whenever therefore we find the purging unwilling to yield, we ought to attempt the cure by applying blisters to the head and the local destruction of blood, as this is the most proper method to pursue in such cases — It very often happens that the sympathy existing between different places may cause a disease to occur at a very great distance from the seat of the injury. Thus a man struck upon the head may have an abscess of the liver, without this last part having received any injury, and this is only to be explained by the nervous communication which exists between the liver and brain, the eiFect of the blow may be such as to produce inflammation of the brain which may cause an irritative action to the nerves of the liver, and terminate in abscess if we are not active in our treatment. I shall now stop short with the sympathies to answer the question I have but little doubt many have been asking themselves, what have they to do with Cholera ? I answer that it is of the utmost importance that they should be kept in view, as will be afterwards shewn in illustrating the manner in which the cause or causes of this, as well as other diseases, operate on the body, and on that account I could not well pass them over. In their illustration I have made them, when practically considered. 14 of some moment to the junior branches of the profession and not altogether out of the way to others. In the mean time I go on to the investigation of another important subject that of. C II A P. 111. ANIMAL HEAT. I state a few points at the onset which it will be of importance to keep in mind. If the sympathetic nerve in the neck be divided, the head begins to lose its action, and the heat of the animal diminishes. If we cut upon the brain, or disturb it in anyway, as in concussion, the heat of the animal decreases very rapidly, and it will diminish in rapidity from the cerebrum till we approach the lumbar vertebrae. Thus an injury inflicted upon the neck will cause the heat to decrease faster than it would do at these vertebrae. Respiration aids but very little in the production of heat ; for it has been observed that the animal dies quicker if the respiration be allowed to go on, or kept artificially in play, the body always cooling much faster under these circumstances. There is also attending an injury of the nerves a partial or general paralysis of the system, if the wound penetrates at the ear, there is a paralysis of the greater part of the body, the extremities become cold, and the motion is in such instances lost. In others it is only so for the time being, and although it may gradually return, yet it does so with slowness, and with much less power than formerly, for the animal seldom recovers its former vigour. Animal heat I believe to be generated in a major degree through the medium of the nervous influence, and to be kept up by an equalization in the circulation of the blood. An instance may be adduced of a want of a proper 15 degree of heat in paralytic affections. A paralytic limb when first attacked, becomes not only motionless, but also loses its temperature, as compared with the other, if healthy, and finally becomes shrivelled or shrunk, especially when the disorder is of loncf standing, I am well aware that in a few cases of this sort, the parts may gradually recover their heat, this however is seldom to be met with in old bed-ridden patients, from such a cause, as about to be stated. During the night they are not unfrequently heard crying out that the affected limb is colder than the other, and request to have it well covered. This at all events proves that the feeling of the injured member is materially affected. When however the injury has been so far recovered from, that the heat of the injured limb is on a par with other sound parts of the body (for here it may be observed that artificial heat is but little adequate to keep up the efficient action of the limb, I mean so far as the nervous energy is concerned,) what let me ask has taken place ? We are all well aware that nature makes attempts at the restoration of all lesions of the system, sooner or later, she appears to accomplish this through the medium of the uninjured nervous twigs supplied from other sources than those situated at the part which has sustained the injury. The heat is therefore kept up through this medium until its own nerves have sufficiently recovered their energy ; somewhat in a similar way that blood is supplied to a limb after the operation for popliteal aneurism. It must at the same time be recollected, that I do not state that these nervous twigs are enlarged, but only that they have an additional stimulus added, so as to enable them to make good the deficiency which they are required to supply. These things can only be expected to 16 take place, in cases where the injury has been light, or insufficient to destroy the principal nerves of the member. If the paralysis be extensive I apprehend that nothing of this sort can take place. From the above we see an instance of that divine interposition so often met with in the animal economy — nature accommodating herself to existing circumstances . To illustrate the point further, every one knows what takes place after the operation for popliteal aneurism. With the decrease of the circulation there also takes place a diminution in the supply of heat (for we must now look on this as a sort of animal secretion) below the parts operated on. Here the advocates for an opposite opinion may exclaim, this is exactly what must be taken in support of our argument, the circulation being impeded, the heat decreases. Nothing can be more correct. It may be answered, however, that the absence of the heat does not depend upon the deficiency in the circulation, for there is generally enough of blood in the limb from the anastamosing branches to maintain the life of the part, although this maybe in a minor degree, but from some other cause which they may not be inclined readily to admit. What will they say to this deficiency of the circulation, acting in such a manner as to ab~ stract the nervous stimulus from the very nerves ramifying in the limb ; for this fluid I apprehend is one of the exciting agents to the nervous system, not only at its fount, but also through every portion of it, and that these two functions act reciprocally on each other, and the blood in proportion to its purity on the whole, when impure we may certainly expect to have some disturbance in the body. What takes place after the circulation becomes more freely established ? The heat of the limb becomes natural in proportion to its restoration, the functions of the parts being thereby gradually 17 restored. Here again my opponents will say any one may plainly perceive, that when the blood circulates with freedom, the heat is restored, nothing then is more plain to us than that heat must be produce:! by the blood. I have only to say that I gave them one example of perfect circulation with a decrease of temperature, in the case of paralysis and now it may be added, that the nerves are supplied with a due degree of stimulus, and that they will act well. How can this be, they ask seeing that the main branches of the nerves have not been touched in this last instance, they of course will continue to act well no matter what the state of the circulation. Here also I answer that the nervous influence of parts is kept up by a due degree of blood supplied them through their whole extent, and that the nerves are not only capable of being stimulated at their extremities, but throughout their course, by the blood as well as by other stimulants j so that an action once commenced at the extremities, may in certain instances be propagated to their origins, and vice versa, such may be observed in metastasis, or the transplanting of disease by the medium of sympathetic action, from one part of the system to another, as sometimes happens in gout or gun-shot wounds. I am therefore of opinion that a proper distribution of the blood is necessary to a due degree of nervous energy being kept up. Let us pursue this highly interesting subject a little further, I ask what is the effect produced by the application of a superabundant quantity of heat, in an artificial way, to the case of aneurism above noticed, or to an amputated limb, or to severe frost-bitten parts, or I may add a hearty meal after long fasting and exposure to excessive fatigue. If the heat is over and above that which ought to be applied, the parts are to a certainty as effectually destroyed as if gangrene had already occurred, 18 merely from the application of an over degree of stimulus which they cannot withstand. Those who choose to refute these and the following opinions, I have no douht will be well aware that such things do occur, and, if they are sufficiently grounded in the general principles of surgery, they must also admit that it is one of the most dangerous things possible to apply too much artificial heat in such cases. For, the parts are now weak, under temperature, and cannot withstand this stimulus. The nervous energy of the parts is hereby increased, heat is soon present in these places themselves, over and above the healthy standard. I could give some examples from my own observation, but pass them over, contenting myself with the fact as above stated. Now in what manner does this increase of heat and action occur, not from an increase in the circulation, for in aneurism, or even sometimes in amputations this cannot be the case, the heat we contend is materially lessened, from an abstraction of the blood, and thereby causes a deficient supply to the nerves. The manner in which the supply of artificial heat, greater than is compatible with the now •decreased energy of the part, acts may now be stated. It produces an excitement in the extremity of the nerves, and being carried from thence to their origins, causes an irritation or stimulation through the system generally ; now this may come to reach the diseased parts themselves, thereby constituting what was at first a local, into a constitutional complaint. Many examples of a similar sort could be given, but those advanced will be sufficient to establish the point in question. Why have I instanced hunger after long fatigue as producing the same effects. If people in these circumstances are allowed to eat freely, we will have many patients, amongst a boat's crew, or any other body of men, who may have been unfortunately 19 exposed to them. Care must therefore be taken at first that they have not too much of warm liquids, or even solids allowed them ; we musthave recourse to those articles gradatim, as the stomach and powers of the body will admit them to be used with safety ; if unfortunately the men are otherwise treated, the system is soon thrown into over-action, and will be in the utmost danger of being overpowered. I give two other familiar examples of the nerves being the medium through which heat is supplied. Pressure tor some time against the nerves in the hams or armpits will not only cause a want of sensation in the parts that are supplied from them, but will also cause them to feel colder than those of the other limb for some time after. Another example of nerves supplying heat in the first instance, and then an excitement of the vascular action, may be deduced from the act of blushing, for every one knows and I dare say has felt a glow of heat in his cheeks, before anything like a blush was apparent. In addition to what has already been stated as to the production of animal heat not being dependent in a major degree on the circulation of the blood, so far as the fluid itself is concerned, it will be proper to go on with the illustration of the question. A vessel filled with, water and set a boiling, we cannot make the water hotter by any means, so long as we allow the steam to escape, even by supplying as much fuel as we please, since its capacity for heat at the boiling point is only 212^. The reason that the water cannot be rendered hotter is, that the heat which accumulates at the bottom and sides of the vessel rises to the surface, and flies off in the vapour, in this way then is the superabundant quantity got rid oif, the thermometer, therefore, must always stand at the boiling point. We may, perhaps, from this draw 20 something regarding the evolution of heat in the human body. We know that the temperature of the blood under all circumstances is about 98° ; this is generally the case under whatever alteration of temperature the body may be exposed. If, however, a greater proportion of heat is present than the man can well withstand, it must either accumulate in the system, or be got rid of in some other manner. The way in which this is sometimes, or generally accomplished is by the perspiration, which we may, for the sake of illustration, consider as something analogous to the process of evaporation from the boiling water. This being allowed, the solution of the question becomes easy. But if the heat, in either instance, be shut in, then there must be either a bursting of the vessel, or disease engendered in the system. Perspiration then is to be looked on as the cooling process by which the body gets rid of its redundant heat, and by which it is maintained at a pretty uniform standard ; this too in almost any clime of moderate degrees of temperature, provided the person has done nothing to heat himself, by giving an increased impetus to his nervous system, and thereby adding activity to the circulation. We may thus easily perceive the manner in which an accumulation of heat in the body engenders disease, in those who have not the regulating 1 medium in a proper state, and it particularly manifests itself on those parts which from their bulk are most susceptible of its actions, such as the liver, brain or bowels, &c. this is pre-eminently the case in hot climates. It is unnecessary here to say what the effects, or ultimate terminations of these primary disorders may lead to. Thus, then, have I accounted for the general laws which are at present allowed to be tenable; as yet little, or nothing, has been said in respect of the nervous play 21 in the above processes. Having stated what takes place from the flow of perspiration, our attention may now be directed to some other phenomena attending the production, or generation of animal heat, since we often oee it reduced when the body has been exceedingly hot, without perspiration taking place, consequently the reduction of temperature cannot be supposed to depend on the insensible perspiration, even although the blood be 98° and the heat of the body above 100°. Let us turn our attention to a patient in a bath of 112° or upwards, here we will find that after he has been in it for some time, his body will return to the same degree of heat as when he was immersed, but this is not a healthy man, it might be better to take one in health, when the body is very hot, or even of the ordinary temperature, place him in the bath, here we can have little doubt as to the result, so far as regards the thermometrieal observations, •which will not, especially in the latter instance, be materially altered in his new position. In such cases there can be no evaporation from the surface by the process of perspiration, although he may be perspiring copiously. This objection is met by a sort of ingenious hypothesis of Dr. Cuvrie, he says that the process of perspiration is a cooling one, even when engendered internally, and before it breaks out on the surface, this is to be ascribed, he says, to the circumstance of this fluid having a greater capacity for heat than the blood, and thus absorbing or reducing the temperature in the moment of its formation ! that a fluid exists in the blood capable of doing this is certainly a very ingenious thought. The heat surely must be latent, for it does not seem to shew itself in any other way than by its evaporation on the surface in a dry day ; for when any one is wet with sweat, in one that is damp or rainy, he will by no means 22 be greatly benefitted by perspiration, but this may add much to his annoyance or disquiet. Why does this cooling process not occur in the case of a patient who has been sweating in bed for hours together, if the perspiration be a cooling process, at the moment of its formation* we ought to have hectic patients in a cold climate almost frozen to death in winter, and the blood robbed of much of its heat. Some may think that we should be more cool and comfortable in a hot climate than we usu- ally are, or even in bed, the parts that are covered with perspiration should feel the coolest, especially when not exposed to any current of air, but we all know that such is not the case ; the reason of this some may alledge to be very obvious, in saying, that it is only superabundant heat which this process carries from the system, and that it is constantly engendered under such circumstances. Such a notion maybe well enough adapted for those who think that such properties exist in the perspired matter as generated in the living body, and this too in the warm bath above all other places. To me it appears that such a process as the " absorbing or reducing the '' temperature at the moment of its formation" cannot take place, or even be admitted on chemical principles, or any other known laws, to the extent required to account for it. To what then are we to look for the solving of the phenomenon. The nervous system is that alone through which it can be satisfactorily accounted for ; since by accommodating itself to existing circumstances, bysome laws of its own, it produces a uniformity of action as regards temperature, either in a hot or cold climate ; to this power therefore are we to ascribe the phenomena which take place in the animal machine for withstanding the ennui, and oppression of the one, or the over bracing effects of the other, as well as all the cold chills and other 23 attendants on it. Those who wish to prosecute the subject experimentally will find it so, and that the temperature of the human body is pretty uniformly the same in all climates, under the ordinary circumstances at present met with. Let us take the case of patients, however, in whom there exist frost-bitten parts, or those so severely benumbed with cold as to resemble more halfdead animal matter than living. The parts here are so deadened as to destroy, for the time being, the influence of nervous supply, but let them be warmed a little, if the heat be over and above that which ought to have been used we have to a certainty an increase of action, with every probability of serious consequences about to ensue, this does not entirely depend on the sudden supply of blood to them as the cause of all this disturbance, but is to be explained on the supposition of an over excitement of the nervous power of the part, as I have shewn in the case of aneurism, and I also state that such an occur, rence would have taken place from a continued supply of artificial heat, even although the blood was circulating in a minor degree. Besides this very irritation of the nerves causes an increase of action there, this may appear at once evident, from a greater impulse being given to the circulation of the blood, where we have no mechanical obstruction existing, than in those instances in which it is present and in other parts of the body. Every one knows that in phlegnion and in a paronychia, that the arteries of the part beat more forcibly, and more frequently than elsewhere, which is to be explained on an increase of stimulus being given to the nerves of the diseased part, thereby causing an increased action of the vessels, and this applies also to other portions of the system. The blood vessels therefore are plainly under the influence of the nervous power, as well as all other parts of the system 24 depending on them in a major degree for their vitality. The above borders en seme points, connected with the causes of inflammation, which I pass over for the present. ]>y the above reasoning we may explain the manner in which inflammation of somepartsis produced, and this too on the principles of the sympathy of communication. Other objections I start as to the blood being the generating power of heat, and state that in febrile affections we may not unfrequently observe a profuse perspiration, under certain circumstances, not by any means carrying off the superabundant heat, or even lessening this in almost any perceptible degree, therefore it is but reasonable to conclude that it is not the only process by which the body is cooled, or that it even reduces the temperature "at the moment of its formation." I have already stated the agents which do this without the perspiration. From the above, the inference may be drawn, that there is a natural, as also a morbid animal heat, according as the individual is in health or disease, that these two states of heat depend on something else than the generating power of the blood at the temperature of 98°, even when the circulation is slew or quick, and are independent of chemical laws, so far as these have any influence over living animal matter. But do not imagine that I lose sight of the action of the blood as assisting in the production of this ; by no means, for we must find that there is a sort of reciprocal action hetw r een the two powers, neither let any conclude that I for a moment think that the blood is the governing, or regulating power in accomplishing this important process. The blood is necessary for keeping up a due stimulus to the nervous system, from which it, in its turn, even receives its vitality ! In this way then are we enabled to 25 account for some actions that depend on vital principles alone ; as well as the impressions made on the sensorium commune, through the medium of the external or internal sentient faculties or organs. T may add that, on the supposition that the hlood is the only means of propagating heat, it might he difficult to account for the skin in fever determinately retaining its heat and dryness, until a certain period, then all at once becoming drenched with perspiration. "Why, let me ask, does not perspiration occur upon the reaction, and the heat of fevers ? "Why dees en intermittent in England so frequently go through its three stages of cold, hot, and sweating, each lasting for a considerable time ? Why does not the sweating occur in the hot stage ? I have stated that perspiration does not remove the heat in many instances ; even from this we may conclude that it depends on the nervous power, and also that there is a difference between the production of heat in certain cases as regards perspiration carrying this off, as well as that there is a dry heat of the surface capable of being maintained independently of the state of the circulation, and according to the condition of our patient. Why is it that, at the commencement, or even during the progress of fever, or other diseases, the under part of the body will be preternaturally hot, with the upper portion cold, or the reverse, both places being exactly under the same conditions as regards covering, and the natural distribution of the blood ? — this others as well as myself have experienced much to our annoyance. In cholera, the patient not unfrequently complains of great heat, just as happens in some cases of fever — for example, typhus, in which, while the body actually feels colder to the hands of another, the feeling to the patient is sensible and acute, therefore, he often complains of it. 26 It is truly astonishing, when Sir Gilbert Blanc was perfectly aware of the fact, that in amphibious tribes and fishes the standard of heat is but very little above that of the circulating medium, and with a power of resistance in maintaining their specific temperature either in cold or torrid climes such as not to alter it, that he did not look for some other power than the blood in order to obtain a satisfactory explanation. He says " that temperature is both raised and depressed by some " power essentially inherent in life" " this is most 11 observable in birds, for in those, even of the smallest " size, the natural heat is tenor twelve degrees above the " human." Had Sir Gilbert's attention only been directed for a moment to the nervous system, it is thought that this circumstance could not have escaped his deep penetration after more than " fifty years meditation and "experience." Such however is the fallacy of human reasoning and human pursuits, that we are but too apt, even as logicians, to pin our faith to an honoured theory, or for the support of that most important discovery of Harvey ; so much so indeed, that we may possibly give it more influence over the phenomena of life than even its splendid author could have contemplated. I am afraid that in the present time it has received a shock of diminution from which it may not easily recover, in so far as it attempts to explain the generating power of animal heal, when this is considered as the primary principle of production, and I am still the more astonished at the upholdingof this doctrine when we have the following from the author above quoted. " When it is considered how immea"surably greater theahstractingpowerof the atmosphere "is in these small bodies, in consequence of the ratio of " their surface being as the square of their mass it ia "utterly impossible to account for this on chemical 27 "¦principles and must depend on a specific generating "power furnished in various degrees to the respective "species of animals, and it must be astonishingly great "in small animals to enable them to resist the strong ic power of abstraction in the external medium. This " argument is rendered still more strong by what is (i found to take place with regard to some insects. Let " the bulb of a thermometer be thrust into a swarm of "bees, the heat will be 97° or 93° that is as high as the "living human body." This last circumstance of course can only be properly explained on the supposition of accumulated heat. None for a moment will suppose that a bee is capable of raising the thermometer to 9S 0 , thus evidently shewing the source from which the heat is derived. It is the more remarkable however, that he does not attempt to account for the existence of this principle more particularly, when we find him making U3e of the words in Italics. I am almost irresistibly lead to the conclusion that our author, although he does not, and perhaps was rather unwilling to express it, must have been aware that there did exist some other power than the circulation of the blood for regulating the animal temperature. This very passage must have calledthe attention of others to the investigation, hence the important results which lead us to an opposite conclusion. Sir Gilbert, as well as very many others the advocates of the opinion, that heat is generated through the medium of the circulation, believed that oxygen the supporter of combustion is indispensibly requisite for a due supply of animal heat. But life, although in this way compared to a lamp continually burning, and the comparison, for aught I know, may be apt enough, yet it may be safely stated that man is not a lamp, and that the blood is not the means through which this species 28 of vitality is kept in play. The simile might possibly apply could we see, or even suppose, that the body of man was the vessel and the blood as influenced by the nerves the oil, but this vital oil would not act without some power to put it in action. The nerves, therefore, affording vitality to the blood may thus cause it to shew light to the whole body, and in this way the secret and invisible fire may be kept in a continual glow. This is, however, wandering a little from the point ; a due supply of oxygen is furnished merely with the idea of purifying not heating the blood ; this must be the case if we view life as consisting of a multiplicity of actions, each depending in a great degree on another, and all in particular on the due and efficient performance of the nervous power, as well as, the supply of blood ; these two systems go hand in hand together, and the nerves will continue to act so long as the blood is properly purified, and regularly transmitted to the different compartments of the body. Oxygen will only give heat under certain circumstances, and we all know well, that it is a supporter of combustion, but the flame, or a sufficient degree of heat, must first be in existence ere this can take place. I am well aware that the sun's influence producing the various orders of divisible prismatic colours in its different rays ,each of them, according to its colour, possessing more heat than the others, even one of them as it has been statsd is in possession of magnetic or magnetizing powers, may have something of a specific action on the production of animal heat, so far as the selecting power of the blood is concerned, and that it may be absorbed, when the air is presented to the large expanse of the nvngs on purpose for purification, but through what distinct medium or action it is accomplished does not appear, nor do I mean to inquire into it, suffice it to say 29 that oxygen in any degree of purity does not give th<* heat to the blood, since those who breathed a more pure air, or those in an atmosphere to which a quantity of oxygen was added, would be hotter than other people, but this is far from being the case. Our author (and I like to keep by one when he is very good) however states that oxygen is furnished for this purpose, and that this v is extremely plausible when it is considered that the " specific temperature of different orders of animals, exceeding that which they are capable of bearing, causes them to decay. Do such things not shew that there is something very noxious in the atmosphere at such times, and what let me ask is to prevent the presence of other ingredients at other times, capable of proving injurious to animal and vegetable life ? 37 I apprehend the more we look into the laws and wonder workings of nature the more we will find to admire. We may even see the most stinted scale of existence, whether in the one class or other, when not possessed of a traceable nervous power, blessed with a something in this way, and find that it is acted on by the influence of external heat, or that of the medium in which it is placed. It is a well known fact that light is divisible into different rays, some of them possessing heat : it does not seem preposterous, therefore, to imagine that plants, or other substances in the vegetable, and lower orders of animal life, may be kept alive by absorbing these calorific rays. Animals, under these circumstances, only exist asplants do. Some may object to the above reasoning, by saying that plants or other substances have not the power of selection, or are incapable of separating these rays. How can we know that the y imbibe heat, it is surely more reasonable to suppose that they have this power, slender as it may be, than that they have not, and that it is always adequate to keep up their very limited existence : they are surely as capable of doing this as inanimate bodies which absorb heat from the atmosphere according to their different capacities for it. Here would be a fine field for expatiating on the different effects of colour and texture, but I pass it over, allowing those who have more leisure to prosecute it. As to heat being in fluids, where there is no organization, it may be answered shortly by stating, that where there is no heat present, there can be no life, and where there is no life, we are at the end of the subject, since such must of necessity fall under the laws governing inorganic matter, therefore fluids are exactly in this state; but then there is the blood of man and other warm blooded animals the most important of all 38 fluids, possessed of a high nervous power, I take this as the best example, as in the opinion of Hunter, it is possessed of life, nay some of the present day may even adhere to its vital principles ere I conclude the subject of Cholera. If they say that the blood receives life by being acted on by the nervous influence, as it circulates through the whole body, — that in this way, it keeps up, and retains its various properties, I am of their opinions, and these are rendered extremely probable when we take certain diseases into consideration. As to oxygen being the sole agent in the production of the animal temperature, I shall introduce a quotation which may serve to shake such an idea. " Though oxygen may contriu bute somewhat to the generation of heat, its chief ac(i tion is that of serving as a stimulus to the living pow" er in generating it, for it plays an interesting and ac** tive part as an exciting power throughout all nature ** both animate and inanimate, being a main consti" tuent in water and atmospheric air, and indispensible " to combustion, and no animal exists without more or "or less of its influence, either by respiration or other(' ( ' wise." In proof that artificial heat has a great and wonderful influence on vegetable and animal life, I wish only to bring forward an instance or two of the latter sort, the chick in ovo, will serve for an illustration. We know that the Egyptians can produce an abundance of chickens by placing the eggs in ovens properly regulated as to temperature ; here, however, if the warmth be either too great, or too little, nothing of the sort would take place. I only give the fact, for I do not mean to investigate the matter further as to whether the eggs are, in the first instance in possession, of a nervous power. Although the idea may be somewhat problematical, I believe that ftetal life, wherever met with, only 39 requires a due proportion of heat for a time, so as to bring this into active operation, — it then lives by laws peculiarly its own. But this is bordering on another important subject which I do not wish to have any thing to do with, at least for the present. Examples must be familiar to every one of the sun's rays being capable of producing the same effect in other instance — I shall mention two. The eggs of the turtle and alligator, when deposited in the sand by these animals, after remaining some time, are hatched by the heat of the sun. It is thought that enough has now been advanced to prove that the nervous power is the medium through which heat is, in the major degree, generated in the system of man, and that any cause, which disturbs, or destroys the actions of the nerves, will tend also to the destruction of the heat of the body, or any thing in short which deranges their power will, to the same extent, either increase or diminish it — I have shewn also that animals and plants are much acted on by the presence of heat, either as it exists in the atmosphere or as generated by themselves. I trust that, in proceeding so far with the investigation and illustration of this highly interesting question, I have not overstepped the bounds prescribed. If the above views be admitted, then there is but little doubt that we must have obtained much information concerning the proper treatment of many diseases, which have hitherto baffled all our best directed energies. The application of this subject to Cholera will appear, when it is stated that such will enable us to account for the cold feel of the skin, also for the paralytic affections which we not unfrequently meet with during the progress of some cases of the attack; for we will invariably find that a perfect paralytic body, or member, has always much 40 less heat than one in health. As to the occurrence of paralysis of some of the muscles in Cholera, as that of an arm, a leg, &c. we need not be astonished, when we consider the violent action of many of the cases, in which we find a gorged state of the veins of the internal parts, or even an effusion of blood somewhere about the cranium, as is found on inspection ; hence such occurrences will take place as readily in Cholera, as in cases of apoplexy, concussion of the brain and some other diseases, in which the nervous power is either heavily pressed on, or in which severe lesion has been inflicted on the cerebrum, or medulla spinalis, or, in proportion to the nature of the power applied, whether from a gaseous substance or otherwise, for those may be so potent as at once to destroy their power, either through a part of the extent of the system, or at the very origins themselves. Hence we can easily account for the appearances met with in a Cholera case, such as the eye being fixed and immovable to all external stimuli, as sometimes likewise takes place in concussion, and oftener in compression of the brain, or other diseases ; we may have an incapacity for speech, or a very low articulation, an insensibility of the patient to objects around him, a torpidness of the system, after the attack has continued for some time, with many other phenomena that take place during the progress of the complaint. As the nervous power of a part, therefore, is worn out, or oppressed, so, in proportion, will we have an imperfect performance of its actions, this may either manifest itself in particular parts, or in the whole body, since where there is no life, we can expect no action, and, where there is nervous supply, we may expect to meet action in proportion to its energy; when any cause is in existence to call it into operation this may either be a weak state of it, or the reverse, 41 for over excitement in a part does not necessarily produce an increase of action, as it may be of the depressing sort, especially in worn out constitutions ; over excitement may be said to produce spasm in a healthy stout body, but in one in opposite circumstances we will have a state approaching to paralysis. Having stated the above influence of the nervous system, the next subject for investigation is that of CHAP. IV. THE BLOOD AND SECRETIONS. It is imagined that most medical men, if not all, will admit that a proper digestion, and performance of the respiration are necessary to the maintenance of healthy action in the body ; also that, upon the efficient operation of these, the blood depends for its richness and purity. A man with a good digestion, I do not mean a glutton, but one who properly digests what he takes, and in sufficient quantity for the maintenance of his size of body, with a free respiration and good air, will have proper blood, as the product of the conjoint actions. A man who, on the other hand is unfortunately troubled with a bad digestion will have a less rich blood, although his lungs are acting freely and inhaling a pure air. Let any of the accustomed secretions in these men be impaired or stopt, as that from the skin, or the bowels, the bile, or the urine, &c. ; under each, or all of these circumstances we will have disease produced, which will equal in extent the cause from which it arises, or will run a course in proportion to the susceptibility of the man for imbibing impressions, or for resisting them. .The stopping of any, or all of the secretions, therefore, is sufficient to produce disturbance of action in the general 42 system, as the blood cannot so readily get rid of the impurities which it has contracted from going the rounds of the body. Hence it also follows, that the longer the duration of this disturbed action, the more likely are we to have disease of some nature or other induced. In illustration of the above it may be proper to state that the bleed, in its visits to the different parts imbibes from them impurities, which are got rid of through the process of respiration, &c. ; but if the air be bad, or the accustomed evacuations checked, w r e have one, two, or many causes operating towards the production of disease, which may even occur to the extent of the exciting cause or causes, whether as existing in the blood, from its not being able to free itself go readily from these impurities, or as arising from other sources. When we observe all the secretions checked in any disease, as happens to be the case in Cholera, the patient must soon die, did this proceed from no other cause than the excess of what has been called azotic particles in the blood, or the other ingredients collected in it from the various compages of the body ; thus it may be said that man generates a poison capable of destroying himself, and that speedily, if not removed by the re-estabiishment of the various secretions. We see, then, of how much importance it is to keep these free, and properly regulated. Under the circumstances of one very important secretion being checked, the lungs, in co-operation with the other emunctories, may be unable to throw out the excess of impurities, even in the most pure air, — that they may do so under certain states may be true, but, if few grant that the lungs are only for (he purpose of puriying the blood to people in health, it surely is not to be expected that they can do more than this, when the other secreting apparatus is affected by disease, and 43 thereby rendered incapable of throwing off the onus of one, two, or three important and extensive secretions, which are now supposed tobe impaired, or totally checked. The blood, therefore, being rendered impure, in a major or minor degree, from these causes, will still have such impurities going on increasing ; these, when accumulated, as accumulate they will, must tend strongly to the general disturbance of the balance of healthy action. We thus see the great importance of paying strict attention to all the secretions. A checked perspiration givs rise to headaches, fevers, bowel complaints &c. anl the reason of these occurences may be explained on the principle of a sympathy of communication. When the secretions of the urine are impaired we have much excitement produced ; this sooner or later ends in fever. The bile being deficient in quantity, or obstructed or vitiated, gives rise to inflammation of the bowels at times, or to serious disturbance of the whole powers of the body, and a suspended secretion of the faeces may also occasion an inflammation in the alimentary canal, the liver, or even fever with many other diseases. There are many other complaints that have their origin in these several causes, which it is unnecessary to state here, my only wish being, for the present, to draw our attention to these facts, in order to point out the vast importance of attending to their proper regulation. I do not intend to dive into their several causes, or the manner in which such may operate on the system; by referring to what has been said, on the sympathetic actions much may be learnt; I at present, therefore, observe, as a well known deduction in medicine, that it is not one secretion we must endeavour to restore in disease, but all, and this too by a combination of remedies adapted to fulfil many such indications at one and the same time. Thus calomel and opium in combination — 44 antimony and calomel, or this last, with a purgative, will accomplish many of these intentions, and in this manner we may speedily relieve our patients at the very commencement of disease. I cannot say in every instance, for there are many points to be taken into consideration in the treatment, such as the duration of the attack, since its nature may be of an ephemeral sort, or may be determined to this by our remedies, or the disease may be such as to run its fatal career in the space of a fevr hours; in such instances we must employ more energetic measures, adapted to the nature of the case ; thus in Cholera, in many cases, we would waste much valuable time by having recourse to a dilly dallying sort of treatment, for this is a disease, when of the more aggravated form, in which the axe must at once be applied to the root of the evil, and our best endeavours must be directed to prevent the occurrence of symptoms, or if present, to effect their speedy subduction. When there has been disease existing for some time we will find that there is some secretion not in proper play, we may also perceive that it cannot be restored at once, and that we must proceed slowly and cautiously to work,acting gradatim on the general system by some remedy, or a combination of such as may be capable of fulfilling the object in view. An example amongst the many that could be adduced maybe given in that of diabetes mellitus, in which we will find the secretion of the skin as well as that of the bowels, in general vastly deficient, and acting capriciously, with many other attendant circumstances. Now we cannot operate in these cases at once, perhaps, by the exhibition of Dovers powder so as to bring back the perspi" ration ; but this may be accomplished in time, by a proper plan of procedure. So also in ulceration of the bowels, we may not be able to remove the pain in some 45 cases by the exhibition of opium, but we may lull it for the time being, this, however, will only be for a time. We know well that mental depressions act as a sedative to the whole of the animal and vital powers, suspending, in- a greater or less degree, various secretions of the body, such as the bile or perspiration, and, if of Ion? duration, they will to a certainty produce disease, which in its turn may react on the brain, and this again on the general system. In such cases we may do much good by a discriminating administration of medicines, but the only effectual remedy is a relief from the mental despondency, ioined to pure air, good diet, and as much exercise as the patient may be capable of sustaining — provided he keeps within due bounds. From suppressed secretions, then, we may have diseases as diversified as the characters of mankind in general, these it would be worse than useless for me to enlarge upon, suffice it to say, that whatever produces nervous derangement will to a certainty cause disease, in proportion to the excitement, and whatever produces a stoppage of the secretions will as certainly produce disease, either primarily in the parts, or secondarily in the general system, through the influence of the nervous power, as T shall have frequent occasion to shew in this Essay. Is it not likely that when we meet with a slow circulation, in any disease, that the blood takes up and contains a greater proportion of noxious particles, that also in proportion to its slow movements, and being shut up in the body, it will tend to the overthrow of the nervous power; for Hook on the blood as one of the main stimulants to the general and local nervous power ; hence we may easily imagine the extent of the evil that will rasult from the extensively obstructed secretions, which we meet with in 46 more diseases than the one immediately under our notice. The parts that are destined to be nourished with pure blood will be thus impaired in their action, as no one part of the sytem lives by its own laws, but by those that govern the whole of the animal machine, so a part once attacked by disease will gradually draw in those in its vicinity, and so on until the whole system is under its influence. Therefore, what is to prevent this very cause from acting as readily on the lungs themselves as on any other part of the system, and in this way producing a disturbed respiration, as we see particularly marked in the latter stages of severe cases of cholera ? — orwhat is to prevent this same cause of impure blood from producing an extraordinary action of the heart, and affecting the nerves, not only of this organ, but of the general system so as to induce a more rapid dilatation and contraction of the heart and lungs ? This is not all, the circulation becomes torpid in the larger vessels, and at times so much so indeed, as to all appearance to stagnate there, so that really there is but little going the rounds of the circulation, notwithstanding the hurried respiration and quickness of the pulse. The lungs, being in over action, will of course allow less time for the purification of the blood, and although some might be inclined to imagine that in proportion to its quickness of circulation, in consequence of the now hurried respiration, so should the vital fluid be in an equal degree purilied, since more must go through the system and thus make up the difference between its comparatively slow movements in health. The blood, however, in the former instance has not time to throw off its impurities in consequence of being quickly sent the rounds of the system ; and, as we will find in the generality of such cases, previously healthy, there is always a tendency to a venous congestion, 47 therefore less blood is now actually in circulation than would otherwise be the cage ; this cause therefore, increasing, at length breaks forth in the general system, and produces serious disturbance and numerous diseases, — these existing in degree according to the susceptibility of the patient, or~ the resisting power of his nervous system. Do not, however, let us be deceived as to the quickness, or hurried manner, in which the lungs and heart play their different parts, and imagine that the blood is better purified under these circumstances — no such thing will ever take place, these two functions are now not in their natural state, hence it follows that, in proportion to the distance the blood is removed from them, so does it collect the amount of the disturbance. If the blood could be better purified by the combined operation of the causes just supposed, we surely would have found in the generality of mankind such a state existing — but no— the blood, under these circumstances, is forced on without being allowed proper time for the purification, and this in small quantities, hence an accumulation of ntoms of noxious properties, hence also proceeds an irritability of the heart itself, or of the general system, or of the nerves of the different parts. Do not imagine by irritability that I mean an increase of one or all of the functions of the body, — that is not exactly the full extent of the term applicable here, for we may also have a weak state of the organs induced from the same cause, but less in degree and they may be in a state just approaching to, but not actually in an irritable condition. What are we to do in such cases, as at first supposed, with respect to the increased action of the lungs and heart, are we to abstract blood or not? The former of these propositions certainly seeirs the more proper plan of procedure, but what is to be gained by it? We will certainly 48 subdue these actions in many cases, but in others we cannot do this, although we may moderate them, hence an amelioration of symptoms, but the present existing cause, or that arising from checked secretions, or rather powers, operating on the system, being only in part, and this too, for the time being, subdued, does not necessarily take away the whole extent of the original cause which is now present in the general system ; therefore this being in duration will or may go on to increase, notwithstanding the now lessened quantity, and perhaps partially altered character of the blood. The nerves of the part may have been previously thrown into an unusual state; they may have taken on diseased action, and this, eithersooner or later, according to the peculiar condition of the body for resisting or receiving impressions of this nature. Now this may be all caused by our tardiness in having recourse to venesection, or it may take place from abstracting too much blood, or from the already impaired powers of the system. I therefore, infer, that it is an important point to bleed early in such disorders. The term early, be it recollected I mean to apply to those cases only in which there is sufficient action in the system to warrant our interference. The above, however, may arise from a tardiness, or unwillingness, on the part of the patients in making their appearance for advice. They, therefore, must be to blame for any of the evils which result from a protracted case — such as inflammation of an organ that has occurred, in consequence of their late application, for now all that we can do is to moderate the action, we cannot cut it off entirely, or we may place the part at the balancing point of returning health, or inveterate disease. This is no idle speculation, we therefore require to be on the alert, when we take lancet in hand, to use it with strict attention to existing 49 Circumstances. I defer at preseut entering any further into this point, when, however, the treatment of cholera comes under review then will be the time to state distinctly under what circumstances, we can safely and effectually put this remedy into full force. What is the state of the blood in Cholera ? By referring to the experiments of Dr. Davy, as given at page 13, it will be found that it is much altered, being greatly deprived of its oxygen, and having in its place an accumulation of azotic, or other noxious particles, so that it is almost impossible to distinguish between the venous and arterial. I have seen cases in which this would have defied any one, — even the most strict investigator. Why should the circulating blood be so uncoagu- Inble as we find it to be ? Does this not lead us irresistibly to the conclusion that there is a loss of something, which will afterwards appear to be the nervous power ; the loss of this destroys the properties of the blood, and, as it were actually dissolves it — the more fluid particles having by some means or other escaped, since we in general, especially in the most severe forms of the disease, find nothing but black thick blood remaining.i ng. That the fluid particles are not diffused in the muscular parts will at once appear from the consideration that every part of the body is shrunk or shrivelled, and the intestines in many places are often found contracted ; but we do not find in the substance of these parts many watery particles, as is evinced on dissection. The blood of Cholera patients, particularly in the more advanced stages of the disease, when it can be drawn, is excessively dark, does not readily coagulate, or in other instances in which the disease has fully formed, it is also certainly much altered as to colour ; — does this not shew distinctly that the lungs have not the power of purifying the blood 3 50 in consequence of a loss of tone ? Whether this takes place from an impaired action in the lungs, or from the. deficit of the nervous power (which I shall afterwards, show to be the case) need not stop us at present in our inquiry, hut we may do well to imagine that such occurs from the combination of both, and that this rapid change induced shews an evident want of serum in the blood itself, which may appear satisfactory to those who have seen inspections of Cholera cases, or even from the blood, when obtained in the more advanced stages of the disease. The blood, when drawn from a vein, has been observed not to coagulate at all, and even the serum, which is at times long in separating in the less severe forms, has* been observed as " white as milk floating on the surface." As to blood becoming putrid or dissolved in the progress of fevers ; Dr. Cullen observes " from the *' dissolved state of the blood as it presents itself when " drawn out of the veins, or as it appears from the red " blood being disposed to be effused, and run off by vari" ous outlets and from several other symptoms, to be " hereafter mentioned, I have no doubt, how much so/ ever it has been disputed by some ingenious men, that ny "of us slept in the open air. But in November the nights " were exceedingly cold ; and although there was hardly " any thing that could be called a swamp or marsh on the c: Island, yet intermitents and fluxes made their appear" ance and continued without any very apparent cause, " except this sudden vicissitude of the temperature of " the air. There was indeed a very high peak in the cen'" tre of the island, the sides of which were covered with " thick grass jungle ; and over this the winds blew " towards the ship and tents. There can be no doubt " that hills and mountains arrest the course of marsh *' miasmata through the air, and when a sufficient quan- ' tity of these is collected, they will produce their ef" fects on the human frame, in a similar manner, as if " issuing from the original source ; especially when the " pre-disposing causes are in great force. Hence we " see how miasmal fever may take place on the sura" mit of morne fortunte or the rock of Gibraltar, with? <( out any necessity for the supposition that the febrific i( exhalations arose from these places themselves." We can, therefore, see the reason why some fevers, which distinctly owe their existence to marsh maismata, should occur where we have no reason to suspect the existence of any thing like this acting as a cause ; but, in such cases, there can be little difficulty in accounting for their presence, if we take into consideration what I have already advanced as to the winds carrying about the 78 minsm. This take place even where the nature of the* soil is such as not to lead us to suspect the existence of marshy grounds. But then we are also aware that these neednot he necessarily present for their production, since it has been clearly proved that such soil is capable, under certain circumstances, of giving out an exhalation as noxious as the former. Why should medical men continue to resist the conclusive evidence that may be met with in the statement of facts like the present, in all authors who have treated of the endemic and epidemic diseases of hot countries. The facts are stated, but their deductions, as applied either to their operation, or the effects they produce on the system, have not been sufficiently attended to. Dr. Johnston observes " although the season of the year was not that of au" tumnal remittents, yet the land winds in all seasons, " and in all tropical climates, are more or less impreg" nated with miasmata, and that these had a considera- M ble share in the fever above described, I entertain no " doubt." This he states when speaking of the bilious fever that occurred in His Majesty's ship Centurion at Bombay in 1804. A question of some importance to determine is, whether a ship sailing along a coast, where she meets with winds impregnated with these morbific particles, and at length arriving at a healthy place or harbour, may have disease amongst her crew ; I think that, as a matter of course, the men on board would be exceedingly liable to it. But may not the disease be modified as to intensity, or even assume a new type, by being now in a healthy place ? — it is imagined that this will also alter the nature of the distemper in the ship ; for had she remained in the place where she first contracted the cause, there can be but little doubt that it would have been at 79 leaat more severe, if, indeed, not another form of disease. We need not, therefore, in such cases seek for the cause of the disease in the place she has now anchored at, which we supposed to he healthy, we must look therefore to the places she has been at, or the coasts along which she has been sailing. It would be singular, if, where there is a number of ships lying, and with no complaint amongst them, we should not, under the supposition of the disease having been contracted where the vessel is at anchor, find seamen belonging to other ships precisely under the same or similar circumstance — consequently labouring under the same form of disease. The above, however, depends on some points which must be taken strictly into account. Suppose a ship sails from England, and arrives at Bombay, Trincomallee, or the river Hooghly, without touching at any place, and with no sick on board at the time, she will be particularly liable to epidemic diseases, or those of the country, although there may be a number of other ships at the same anchorage, very healthy, these having been in the climate for a considerable time, while the new arrived suffers from her first exposure. Great care therefore, should be observed by all in command to restrain their men from going on shore, and to keep them living regularly until they have been some time in the climate. A man-of-waron her voyage from England toached at the Island of St. Jago; all who had been in shore and proceeded a little v ay into the interior of the country felt the full effects of the climate. Returning after sunset to the boat fatigued, the miasm had full power over their bodies, and almost all died from fever, even on their first exposure. Had these persons returned before sun-set, the chances are that fewer would have fallen victims, as we know that the miasm acts much more 80 forcibly on the body after sunset than it does at mid-day. It is improper, therefore, to visit places in which such is engendered, even in the morning, until the sun has been up for sometime ; for then we expose ourselves to the mists, or dews ascending or descending, which at all timos have a delitereous effect on the human frame. Bence a good rule to be observed would be not to expose our men either before sun-rise, or after sun-set j this the more particularly applies to wooding and watering parties. But let us proceed a point further, and suppose that, after the ship's arrival, and after she has been in port for some time, many, very many, of her men are attacked, — are we to ascribe this to infection caught at the place, or from the former source ? So long as there are no other ships attacked then we may fairly conclude that the cause exists within herself, and has been imbibed elsewhere ; but if we see other ships also under the same, then we can have but little hesitation in concluding that the cause is of a general nature. That ships, under such circumstances, are capable of affecting one another with any epidemic disease seems highly improbable, so long as we adopt the necessary precautions of free ventilation, cleanliness, &c. and take particular care that the diseases are not allowed to become inveterate from mere accumulation. Under the last supposition another important question is, will the disease from accumulation spread to others? — of this I have no doubt, especially where there exists a free intercourse ; for the air not only around them may become contaminated, but it may even extend its pestilential influence to a certain distance. That there are some diseases capable of spreading this poison further than others, no one can have any hesitation in admitting, but how far this power may extend has never been satisfactorily 81 shewn; but that it is, under certain circumstances, carried about with the prevailing wind I have n ing in Madras roads, had her lower deck painted ; on this her men usually slept, they were not, however, allowed to sleep there during the time that the paint was drying ; at this time they slept on the main deck, which is immediately above the former. In a short time, a case of Cholera occurred which speedily ran its fatal course, shortly after this, several were attacked and there were some deaths. It must be observed that these early cases occured amongst those who had been previously much annoyed with dysentery and who were, at the time, in a state of debility. There were doubts entertained at first whether these cases were those of Cholera or not ; the afterpart of the business, however, soon put an end to all this sort of doubt. For two or three days, from the first death, she did not number more than six or seven on her sick list, but then the disease began to assume a determined aspect. In another day, or so, she went to sea on a cruize, and, before her return, had Cholera cases to the amount of 103, with only 8 cases of death, from its commencement until it entirely ceased. The Surgeon of the Undaunted, very prope rly in my opinion, in the returns to Head Quarters included all bowel attacks, at this particular time, as Cholera cases. In the Melville, in October 1832, we had above 50 such cases, with only 3 deaths. When she first started on the cruize, the cases continued to increase daily until they hauled their wind, or laid },^r broad-side to the breeze ; there was then a sudden and visible change, as regards the admissions; next morning's list preserved fewer, end in place of there 105 Being above thirty in one day, there was not a half of that number, and the day after still fewer ; in this manner, the cases went on decreasing until there was not a single admission. This occupied a period of from fourteen to sixteen days, — she sailed on the 21st August, and returned to Madras on the Bth September 1833. Shortly after this, 1 was directed to joini n her, and wait the arrival of the Melville. It must be stated that there was not a case of Cholera in any of the other Ships at the anchorage, nor any appearance of it on board the "Alligator," which lay only at a short distance from the Undaunted, and the outermost ships in the road-stead, — the only wind which could reach them at/irst being the sea breeze. The Melville traversed the same tract of coast, on her passage to the Hooghly, immediately after, still not a ease of the epidemic, or any thing like it occurred. The Cholera, and a famine were, at the time, committing depredations on shore, and many died, notwithstanding the exertions of the Local Government to avert the calamity. Let me ask why the Cholera, under the circumstances stated, no other ships being attacked, was so sharply dealt out on board the Undaunted. The cause appears to me to be so evident, that few if any can contradict it — it exists in one, or perhaps two points alone, but I would be inclined, almost exclusively, to attribute its presence to the noxious gases emitted from the paint while drying in such a climate, and particularly at such ;i, season of the year. The only objection that can b<*. stated is that the painters slept on the lower deck, (the one painted,) and escaped ; yet this can only go to prove a. point already so well known — the insusceptibility of the human body, in certain cases, for receiving accustomed infect ion, — and that this was one to which such nieu; 106 were habituated there can be but little doubt. I can have but little hesitation, notwithstanding this apparently counter indication, in stating that the bad air which was engendered from the wet paint, by escaping from between the decks, through the hatchways, and coming in contact with the mens hammocks at night where they were sleeping, was the cause of the whole disturbance. This then, was the pestilential blast, and the only one, which passed over her in the production of the disease. The bad air from the paint could only escape by circulating amongst the men ; and I say that these very men, although apparently further removed, were actually more exposed than the painters, who slept on the lower deck. This may appear a strange circumstance to many, but let it be recollected that the windsails, or drying apparatus, dissipated the noxious particles, and prevented them from collecting at the bottom of this deck where these few men slept — this is the reason why they escaped, and why the others suffered ; besides, the great concourse of people on the one deck is also to be taken into account. The Undaunted had just arrived, two weeks before the Cholera appeared in her, from the Cape of Good Hope station, where she had been upwards of two years and a half, and her men had certainly been inured to a hot climate, by having been long at the Mauritius, where she had suffered from dysentery. Immediately before her arrival in India, she had also returned from a cruize on the western coast of Africa, about Sierra Leonne, the river Gambia, and the Island of Ascension, &c. ; thus her men may be considered as habituated to an intertropical climate. Some of her crew, while at the Mauritius, had certainly had attacks of dysentery, but, according to the Surgeon's account, had perfectly recovered,, with the exception of two or three 107 who were, as above noticed, the first to be attacked with Cholera. The Alligator had been at Manilla in the proceeding month of October, and remained there till the 29th November, — the '* Peacock," an American man-of-war, was there, at the time, and remained until a fort-nighfc before the Alligator sailed. " They were in a very " sickly state while at Manilla having lost seven men "from Cholera in as many days." The crew of the Alligator were all this time in perfect health. The cause of the Cholera in the Peacock, is also to be considered the same as that in His Majesty's ship Undaunted. She was rather furiously attacked by the epidemic, although the men before the deck on which they slept was painted, were in excellent health. Therefore the two ships were precisely under the same circumstances, as regarded the severe heat of the weather and paint. From the above, we may draw some important deduc - tions : it will no doubt strike every one as strange that so long as the Undaunted, while on her cruize, kept before the wind, the cases of Cholera continued to increase. But almost the moment she hauled her wind the disease began hourly to decrease, and continued decreasing until not a single case occurred, which happened in a short time after. We need not be surprised at this, when we consider that a ship, before the wind, has not the same advantages of a free circulation of air which she has when sailing with her broadside to it, when it is independent of the windsail — being admitted by every port hole. I think that the above narration of facts, as they occurred, goes far to prove that certain noxious substances, or particles, are capable of producing the disease in question, under certain peculiarities of weather, Tfhich at that time was oppressively hot. There was an evident 108 tendency in the atmosphere to the production of epidemics, as was evinced by the Cholera being at Madras, at the period when this ship was attacked, but that it was owing to the paint will appear when we take into account the Cholera attack of the American vessel at Manilla ; where, I believe, no epidemic of this nature existed on shore. I have, in conclusion, to observe that had there been a tendency to fever or dysentery then the above cause would just have been as likely to have produced these as it did Cholera; for, when a disease is once in operation, and taking the lead, so also is there a great tendency of all attacks to assume the particular type of the complaint then prevailing. There is one deduction of paramount importance, as to painting ships or even cleaning their holds — it is in intertropical climes that such ought always to be done during the best period of the year, and at the most healthy place on the station, and, if she requires to be painted inside, we should see and have our men as commodiously lodged elsewhere, either on shore, or in other ships, as we may have opportunity. An important subject of enquiry is how long does the miasm, as given out from the earth, or other substances, take ere it produces its effects on the human constitution. That there can be no fixed or determinate time for its operation will appear if we take into consideration several circumstances that may have occurred from the time of being exposed to its effects, to the breaking out of the disease. I speak now more particularly with reference to marsh miasm : it has been stated that generally a week elapses, after exposure to the morbific principle, ere the disease shews itself. That this may be a general result I readily admit as regards intermittent fevers, but that, when the miasra is 109 more concentrated, it must act quicker, as in the production of Cholera, 1 have little doubt. Whether this proceeds from certain undefined degrees of the miasm, at its maximum, or whether there is a something else given out by the soil itself, or some change produced in the air, I cannot pretend to state. I can have no hesitation however, in maintaining that the effects are as stated, be the cause what it may. I also imagine that different poisonous states of the atmosphere will require indefinite times for shewing their operation on the human body, and, as in the case of poisons, this may be in the course of an hour, or after the lapse of many days. We need not cavil about the manner in which it gains access to the system, so long as we know that it does gain admittance ; we may soon settle the question when we consider that people cannot be prevented from eating, and breathing, either through the nostrils or mouth, and that we cannot defend the skin from being a means of its ingress. It is imagined that this last is one great channel through which the exciting cause enters ab extern o, — this opinion I advance in opposition to that of most medical men on the point. We have only to consider that the atmosphere is capable of penetrating every body, of whatever densityit may be, — do what we may we cannot prevent the air from gaining access, nor can we press it entirely out of any, or every particle, of animate or inanimate substances. This may be one reason why those who visit and handle small-pox patients or persons labouring under other contagious diseases are comparatively safe, if well protected by oiled silk or bladders on their hands, &c. Thus then, the air, in whatever manner it enters the body, will operate on the sentient extremities of the nerves. I have shewn, or will do so, that they are often the first parts assailed 110 by the disease and that they, in their turn, will propagate the action to the other parts of the system, and this too at times rapidly, nay the attack may even shew itself before this action has got the length of the sensorhtm commune; but, when the impression is made there, it will be rapidly communicated to every portion of the body, and now the whole of the nervous power being brought into action, the certain effects which follow are either speedy dissolution, severity of symptoms, or they may be less intense, according as the powers of the body are favourable for resisting, or will readily yield to such impressions. The nervous system is and must be affected by a number and variety of circumstances as already stated, as well by the duration of time the person has been in an intertropical climate, as by many other collateral causes. It must not be imagined that, by strength of constitution, I mean firmness or rotundity o f body, by no means, since we know that the stoutest suffer not only in Cholera but also from the fever of the West Indies. None therefore, can tell what their fate maybe on a first exposure to the influence of this cause, — in twenty people, it may even shew as great a diversity of symptoms, or manner of attack ; — even in some the nature of the disease, whether this be a fever, a dysentery, a cold, an erysipelas, an influenza, or Cholera, may be altogether different, such depends much on the state of the climate, whether hot or cold, and also on the particular time of the year, &c. It would be almost impossible to point out distinctly the different phenomena that attend each, or every modification of attack. I am convinced that the more closely we examine into epidemic fevers, or epidemic disease of any kind which o^'es its existence to miasmatic particles,, 111 from whatever source derived, the more will we be inclined to believe that all of them operate more or less, from their origin to their termination, on the extremities of the nervous system, through which the other parts of the body are influenced, and that one part, or organ, in particular, will be found to suffer in all fevers — the brain and liver, especially in endemic fevers of the West or East Indies. In the yellow fever of the West, the skin also, after a time, assumes the yellow appearance, but this is when the fever is fully formed. In the fever met with at Batavia, there is certainly a strong tendency, in most of the cases,to assume this characterestic appearance, and it often does so. Can this be said to depend on the absorption of bile ? I should think not, for the yellow tinge does not appear either in the skin or system by absorption at the onset, — when present however, it may heighten the colour. I think that this peculiarity of caste depends, in a great measure, on the nervous power being, in some way or other interfered with, and that it shews this action either through the medium of derangement in the coats of the skin, or in some other way. There is a peculiarity of appearance, as well as sensation, to be met with in the skin of Cholera patients, in the more severe forms of the attack ; in these it assumes a dusky whitish colour, approaching to a light leaden grey, with a strong impression of cold communicated to the hand of another. It is imagined that such depends on an interference with the action of the nerves of the surface, and consists in the total or partial abstraction of their power. We see similar changes occurring in other diseases, and varying in degree and brightness of colour : — may such changes not depend to some extent at least, upon the derangement of these nerves, and does this not take place in proportion to the disturbing cause ? I think that it is not all improbable; 112 for in some diseases of an epidemic and endemic nature, less intense than Cholera, we see different changes taking place in the skin, according to the force with which the disease attacks and progresses. A change is thus produced in the colouring matter of the mucous coat, which now undergoes some modification of action, in consequence of the deficient supply of nervous power, — this operating to the extent, and according to the nature of the particular disease. We should, under all these circumstances, give very guarded prognosis as to the result of the case, since it may. and often does indicate a fatal tendency. I have said that it is not known what the particular change is that takes place, but that it depends on the nervous power being interfered with, many others as well as myself may believe — at all events, the presence of such changes in the skin is always indicative of a high state of severe disease. In all severe epidemics we may by minute, or even superficial attention, perceive some change in it, which will indicate the extent of oppression induced by this all-powerful and wonder-working cause the miasm, or other states of the atmosphere. To shew that the skin does not become yellow solely from the absorption of bile I ask why it assumes that tinge in parts recovering from contusions- It is difficult to suppose, indeed, that bile is conveyed to this particular portion of the skin on purpose to give itthe yellow caste, which is now so evident, without also communicating the same appearance to the healthy surface around the seat of the blow, and beyond its sphere of influence. These appearances are met with in every part of the body from contusion, — as the thighs, breast, back, arms, around the eyes, &c. If bile is not necessary to give this yellow tinge, which, I suppose. 113 every one will admit not to be present in such instance?, I should say it is not actually requisite to communicate (his appearance in other diseases; and that we must therefore look to the nervous power of the part alone, or perhaps to the blood itself. The coats of the skin, from, their own altered state, may assimilate from the blood this colouring material, — being now weakened in their powers, they may form the peculiar colouring matter, as I imagine that all secreting surfaces and vessels secrete different fluids according to the state of health or derangement. This is also rendered highly probable when we consider the debilitated state of the extremities of the nervous system whether existing in part, as in contusions, or from the more generally operating cause which is present in all epidemic diseases. Bile, no doubt, may exist in the blood, but in those cases in which we know it is present, as in jaundice, we are well aware that it produces far other effects than in the fevers and other complaints more particularly under review. We do not see such high states of excitement take place injaundice,even in inter tropical countries, and I think a very fair inference is that it is not productive of the yellow fever, or even the yellow tinge in the skin, at least in the great majority of instances : bile, however,, tfhdn circulating with the blood, either produces disease of another description, or aggravates that in existence, it rffay, therefore, be looked on as a foreign ingredient, which, when present, may excite at any time the disturbance to a greater pitch. In the case of contusions, liowever extensive they may be, we see that this does not occur, arid if not in contusions why does the bile require to be present in other diseases, in order to mv part a- yellow hue to the skin? This appearance may, from a deficit of power in the nerves of the parts, 114 or whole body, pervade the entire surface ; and we know that various tissues in the body are capable of assimilating to themselves certain qualities from the blood, according as their nervous power is in an excessive or defective state of action — under the particular circumstances of health, disease, or the vicissitudes of climate, — such a conclusion is by no means unreasonable. Ido not, however, choose to prosecute this important subject, but now leave it with the distinct inference that bile is not necessary to give the skin this yellow tinge, that, ¦when it is present in the blood, it in general excites much disturbance in the general system, or in particular parts of it ; and also that, when such appearances as those above noticed do occur, the nerves of the surface, or of the whole body, are suffering from a deficit of action, as in cholera, or an increase of this perhaps, as is occasionally met with in yellow fever. That the bile when in excess, and even acrid, as it has been termed, should be a general disturber of the operations of the system need not astonish us, especially if we reason according to the opinions of most of former days, — this the more particularly so when we know that it is not an unfrequent attendant of sporadic cases of Cholera even in India, but perhaps more particularly in Britain, in the hot weather. lam at liberty to ask a question and it is, why should bile, when a little changed, so stimulate the intestinal canal, through which it daily passes the more particularly as it is an inmate in the parts themselves ? One would be apt to conclude that this, as a general cause in the production of many diseases, has been conceded. The intestinal tube, in so far as it is individually or identically concerned,has as little todowith it as any other part of the system ; and although it transmits the bile^ yet this last does not act detrimentally upon 115 the tube but upon its sentient power, and therefore the nerves being irritated or disturbed, it is no wonder that we should have such varied features of disease even as these exist in dysenteries, fevers, or cholera, which occur according to the peculiarities so often pointed out, as those of season, and the different circumstances under which the sporadic cases, and not such as are epidemic shew themselves, as well as the peculiar nature of the reigning complaint. From the above, we may gather the reason why acrid and non-acrid bile may be a cause of disease ; — but that it is a general one cannot be admitted even for an instant. There are other causes to be taken into account, as well as the acrid nature of the bile, which operate not exactly in the same way, but all of them upon the nervous system, producing the vast variety of fevers, and other diseases so frequently met with. The cause or causes, however, producing them being removed, it does not as a matter of course follow that the disease will cease, or the symptoms be even moderated, since the impressions being once made, they will remain in operation until either the powers of the system, or those of medicine expel them. It is one thing, therefore, in the treatment of such attacks, to remove the cause, and another to take away the disease induced. We need not, therefore, be astonished that either a purging, or vomiting, should continue in other disorders, after the ejection of the offending materials, which have been the cause of the whole ; since the impression made on the extremity of the nerves may remain for a length of time, and even become deeply fixed in the system, by inducing* such a change in the condit 'on of the parts as may be favourable to its continuance. Rut to return from these degressions, which I am obliged every now and then to make, for the purpose of 116 having every thing connected with every part of the subject completely and at once before us, I now observe, as respects the depressing passions, that very many medical men have observed that those of the mind, however caused, are a strong incentive to the operations of Cholera. If we look into the various complaints which may be classed with it, or which depend on morbific matter for their presence, we will find that depression of body and mind, either as arising from the state of the atmosphere, or from any other source such as bodily fatigue, will all have a powerful and extraordinary influence in bringing into speedy operation the over-powering one, so frequently alluded to, in very many instances : or, if it has not been as yet admitted, the very presence strongly pre-disposes the body to its influence. The disease may, in certain cases, be said to produce its ravages on the constitution accordingly, and this may even be one reason why the strongest constitutions suffer, since, although their bodies may be powerful, they require as powerful a supply of nervous energy for their support as others do under other and opposite states. The more firm and resisting the mind of our patient is, for combatting impressions of this nature, so much the morechance for him, either in guarding against disease, or giving a more powerful resistance to it when formed. It therefore, follows, that we should encourage all our patients, during epidemic seasons, as much as in our power, even those who are not suffering from them. But after doing all that in us lies, we will find even the stoutest hearts give way to an almost uncontroulaule depression of mind, — particularly during the prevalence of a severe epidemic. It is not the courageous or more than brave, or the coward, who can escape this sort of calamity ; since man, however formed or steeled for facing 117 an enemy, or any other danger, before him will sink at the approach of disease. Does the above not shew that the operating cause of cholera, and other epidemics, exists in, and depends upon, derangement of the sensorial powers, and that the operating influence of the attack makes its first impressions entirely on the nervous system, and that it is in this way that man is robbed of that stability and firmness of mind, which so strongly characterise the bold and undaunted under other circumstances however appaling; — but here is a cause by which he is shorn of it even independently of himself. Many instances could be adduced in corroboration of the above, such must be familiar to every medical man — I pass them over on this account. Some have been of the opinion that certain other conditions of the atmosphere, independently of those already stated, have to do with the production, and are the real cause of the epidemic cholera. We must now turn our attention, for a short time only, however, to the examination of the subjects of electricity, the productions from earthquakes sol lunar influence, &c. Mr. Orton has struggled hard to shew that the grand and overwhelming cause was owing to a deficit of electric matter in the air; but, it is believed, had he directed his thoughts to miasm, as occurring under the different states mentioned, and which I will yet further illustrate, that he would have been much inclined to have admitted the sources already advocated, as being the fertile cause from which the epidemic springs. He says that "it has " been shown that the attacks of the epidemic are ac" companied or immediately followed by rain, cloudy " and moist states of the atmosphere, thunder and light" ning, or light winds ; and from these circumstances " it is likewise inferred that they are also accompanied 118 «by a depression of the barometer." This statement, so far as it goes, is certainly correct, and he has been at considerable pains in collecting facts as given by printed reports, and from other sources within his grasp at the time ; but I must object to his inference. The facts he has distinctly stated, but his deductions are at variance with those advanced ; although, be it recollected, they are drawn from facts j before I enter on the subject which I shall do in as concise a manner as is compatible with the nature of the enquiry, it will be as well, as has been formerly done, to commence the subject with a quotation, since such a method serves as a sort of wedge to open the way. The paragraph is from a published report transmitted to the Madras Government in 1811, as to the cause of an epidemic fever which prevailed in a certain part of India. " What was particularly observable in the " state of the atmosphere at this time, the period too at " which the epidemic raged with the greatest violence " was a denseness in it, sometimes almost creating a dif" ficulty of breathing, a feeling we had occasion to expe" rience about the middle of April at Dindigul : and we ° learn from Mr. Hepburn that at Tinnevelley it was <( equally remarkable and distressing. There was (i besides, during these months, a singularly oppressive " and steamy vapour, which rose from the ground, and ii which gave a sensation not unlike what is occasionally " experienced from a crowded assemblage of people in " hot weather" — " The districts are in many places " marshy ; and much rice is cultivated in them which " requires to be kept under water. They are bounded "on one side by the western Ghauts, the great line of " mountains which runs down the whole peninsula, and "on the other by the Bay of Bengal. Those parts which " are situated on the sea coast suffered least, and those 119 « next the mountains were particularly affected. It was *< the opinion of the Natives that the disease was owing "to the mountains. The villages which were situated « near marshes suffered excessively.'''' lam under the necessity of introducing for the elucidation of this subject a number of quotations, since one man's observations and experience cannot afford an inlight into the whole ; therefore at times we must cull from others, but this has been done in as limited a degree as possible, and wherever met with, and passed over without any further comment, they are to be taken as if they were my own opinions. That the Natives were not very far out in their notions, as to the mountains being the cause, or having something to do with it, as well as the marshes, will at once appear from what I have stated already; but more particularly when we consider, what is narrated as regards the mountains on the Island of Ceylon, they will, as a matter of course, prevent the free circulation of air, and the putrid particles must accumulate near their bottoms : and although the places were not in a stagnant "state with respect to their circulation, yet they were not so well ventilated as they would have been, had there not existed this cause of obstruction : consequently there must be, for a greater or less space of time, an accumulation of the materies morbi engendered, and this is always apt to be increased by the large forests end impenetrable jungles in or near them, as well as the marshes. This then is not electricity, and it will appear more evident from the sequel. The testimony of the compilers of the above report, who, it does not appear had any theory to support, shews that the pec pie near these marshes suffered most. It is well known that on the Island of Ceylon, the winds are prevented from having their full sweep across the country, from the very high mountains that 120 intersect it ; for. when it is the healthy season at Trincomallee, it is the unhealthy one at Colombo, which is on the opposite side of the Island, and in an oblique direction from the former. This chain of mountains prevents the wet and moisture in the one season from passing them ; when it is therefore the wet portion of the year at the one place it is the dry one at the other. Mr. Orton says, " the epidemic Cholera has been fre- M quently found to precede the falls of rain while the " earth was still parched with draught. Nay, so far from " the rain being a cause of the disease, it is a very general, •* and I believe a just opinion, that it actually tends to 14 destroy not only this but other epidemics. Several in" stances have been already related where the disease ** disappeared on the occurrence of heavy rain succeeded "by fine weather. It appears therefore that of all the " atmospherical phenomena which have been mentioned " as accompanying the disease, none are universally " present except those which indicate a ditni" nution in the density of the air and a tendency ** to rain and storms." I have already stated what my opinions are, as regards the appearances which occur during the prevalence of heavy rains, and some other particulars ; I now go on to say, that it has been supposed, as above stated, that the general cause of Cholera depends on a tenuity of the atmosphere, with a diminution of electric fluid ; consequently, it may be supposed, that the air abstracts this from our bodies, and that in this manner the nervous power is impaired. This appears curious indeed, in particular when we observe the epidemic as prevailing along a wide range of sea coast. The supply of this deficit electric fluid, even if it did exist, could be surely easily accounted for on other principles than by 121 supposing that it operated on the body in the way referred to, this could surely be supplied from the waters of the sea, since they must always tend to keep up an equilibrium in the state of the air, and clouds, by supplying the deficit when required. Thus, by restoring a proper quantity of that electricity to the clouds which we know takes place in the ascent of water into the air in the phenomenon of the water-spout, they will prevent our poor bodies from being acted on by this as a cause. A most distinct appearance of the above phenomenon was observed by the Officers and Men of His Majesty's ship Melville when on the passage from Bombay to Madras in March 1834. The funnel appearance was most beautiful and distinct, in short it was one of the most perfect representations of the kind that could possibly be seen — so distinct as to resemble a well defined drawing on paper. We were within a very short distance of it, — it certainly did not exceed a mile, at all events so close that some imagined they could distinctly trace the water ascending from the surface of the sea ; at the place where the mouth of the funnel appeared to be attached, there existed an evident depression, or pit-like appearance ; the supposed ascent of the water, for we had no other proof of the matter than that afforded by the appearance, could be traced to a large, heavy black cloud which hovered at a considerable distance above. There was also a peculiar, and rather remarkable appearance traceable along the whole extent of it, the funnel, which was larger at both extremities than in the middle, had also a well marked and near resemblance to the flame proceeding from the tor of a burning brick kiln, in a cool, dry, and dark night, when the greatest proportion of the smoke has disappeared ; this continued for several minutes. But to return, to the subject, even admitting 122 for a moment that a deficit of electricity were a cause of the disease, the following questions of importance occu — Is the human body capable of parting with its electricity supposing that it possessed much of it under these circumstances ? Would the parting with it produce the appearances met with in the disease ? Would the breathing of air deprived of the greater part of this subtle fluid induce an epidemic ? Can the body give out electricity, as above stated, without a conductor intervening between it and the air ? Besides, what is to prevent the earth from imparting electricity to the air, and thus saving our poor frames from being deprived of that which, at best, is a very conjectural cause of the disease ? To enumerate the various causes which arise from earthquakes, andthe other inexplicable phenomena, which attend convulsive struggles of nature, during these periods, would perhaps be superfluous. I have, however, to observe that, although from such concussions there is something given out, at times, which proves extremely detrimental, yet we cannot admit it as an all-powerful cause of Cholera. It has been stated that every place which suffers need not experience the shock, but the reason why, in so far as lam aware, is not given ; therefore we are yet left to find our road in the dark, as to the manner in which this deliterious principle travels, and to rest contented with what investigators of these phenomena state as to the fact of severe epidemics occurring about such times ;—; — if we are to look on plague as one, then this has on many occasions occurred at or about the period when the shocks have been felt ; from this we must certainly admit that there is something noxious emitted from the earth. This of course shews that there is a something added to the atmosphere, detrimental to human existence ; and the occurrence of endemics might be accounted for., even in 123 those places where the concussion is* not felt, on the supposition that the noxious materials were propagated through the medium of the atmosphere, and in opposition to the prevailing winds, as already stated. From the above, then, maybe drawn a most important inference in support of my theory, that there is a something noxious given or added to the air, which of course was not previously in being nor could possibly be, in any other way, so long as the diurnal revolution continues. But that earthquakes, or the productions of them, are to be looked on as the general cause of Cholera, seems preposterous in the extreme, especially when we know that the disease has prevailed in all countries, without the presence of any such phenomenon occurring at the time, or perhaps for years before, and that when such does take place it is not necessarily followed by disease, although the complaints arising from such should be greatest, one would think, at the place where the shock is most powerful. Even admitting that earthquakes were the grand cause of epidemics, why do we not find this extending along the whole line in which the concussion is experienced, and at once making its attacks in several places simultaneously. Nothing of this sort has ever been observed in any quarter of the globe, else we would have had many parts severely and repeatedly attacked by pestilences, and even the whole of India must ere this have been, at one and the same time, attacked with Cholera, if such owed its presence to this as a cause. But as nothing of the kind occurs it is but reasonable to conclude that, although an earthquake may be present at the time a particular disease appear?, it will surely cease to operate as soon as this is absent, — this the more especially when the disease has been in a manner once extinguished . Nothing of this has ever happened in India., for we see 124 Cholera almost yearly raising its savage head, destroying thousands, breaking out in places that have never experienced these shocks at all, or at any rate not for a great many years, — moreover, that the epidemic at first occupied one year in travelling over the whole of the continent of India. Some may say that the earthquakes do not, at all times, give out this noxious material,or at least not along its whole line of march; I think from this it seems evident, and necessarily follows, that there does exist another general operating cause, and that this depends, in the manner stated, on the nature of the soil, and on the woods and jungles, &c. and that this noxious principle is capable of being produced every year, according to the season, the climate, and the other varying circumstances attending its presence. The appearance of the cholera has been ascribed to sol lunar influence ; and however Medical men, at Home, may be inclined to deride the opinion, that this is an aggravation of disease there, yet, in India, we have more to do with the notion. I shall only attempt however, to refute the opinion, that the existence of the epidemic is dependent on this as a cause ; lat the same time, admit that it may possess some power over certain other diseases, or on the constitution of man. If cholera depended on the motions of the moon and the other heavenly bodies, why does it prevail incessantly for months in India ? — nay, its very continuance from year to year would lead us almost at once to give the negative to the question. The difference existing between places attacked, and those suffering at the time, although not removed far from one another, so far as the latitude and longitude are concerned, seems to shew that such cannot operate as a cause. If, as imagined, the disease owed its existence to this, why have we a particular district or 125 village attacked, and these not many miles distant from others equally populous and under its influence. Why does thedisease continue its depredations during a whole period of the lunation, without abating one iota of its virulence ; this runs counter to the opinion of Mr. Orton who supposes that the cholera is more mild at two periods of the moon, as between the change and the full, but it is not invariably the case, for we will find the epidemic more severe or mild, according as the weather is good or bad, or approaching to the interval between the two periods, for reasons sufficiently obvious. Besides, if such were the case it would only shew the moon's influence over the disease, not in producing it. Why does the disease play its eccentricities in the division of an army by only attacking the centre, and leaving the wings free, or by attacking one of the wings, and leaving the other two divisions free. The above I expect cannot be satisfactorily explained on the supposition of sol lunar influence being a cause of the production of cholera ; it, however, admits of the easiest possible explanation on the supposition of the miasm as arising from the soil, or the other sources mentioned. One part of the camp may be situated on soil which parts easily with these noxious properties, and the other not. This is the reason why it shews itself in the particular quarter in the first instance, and, in proportion to the tendency of the soil to part with these noxious ingredients, under the various circumstances of moisture, dews, &c. so will the liability increase. As the diversity of soil in all quarters of the world is great, and this too even at very short distances, the same field or place of encampment, for example, may have a soil possessing a multiplicity of properties, — one part of it may be marshy, or may indicate the remains of a marsh, by being spongy to the tread, — it 126 may he clayey or of a more imbibing quality, — it may be rocky, sandy, or the like; — all these things therefore making a difference of such importance as to be regarded strictly in the selection of ground proper for an encampment, especially at particular periods of the year, when we know that an epidemic is likely to break out, in the district in which our army may be desirous to encamp. The moon has certainly a powerful effect over the inhabitants of our globe, and the diseases with which they are assailed, and as it is also wonderfully manifested in the production of the tides of the ocean, so it may certainly have a corresponding influence over the air; but I have already shown that neither its density nor its tenuity can avail much under these circumstances ; but that it has a manifest effect onsomeof the diseases of India most men will admit, who have seen much of intermittent fevers there, particularly those of long duration, and cases of lunacy, or such as approach to it. I knew a Captain in one of the regiments belonging to the Bombay establishment, (and such cases are by no means rare) who had an attack of fever every month, and this had occurred for several years ; the paroxysms were always greatest when the moon came to her full, and the intensity of the symptoms decreased as she diminished in her last quarter. I also know an officer, in His Majesty's service, who has, since being in India had much mental aberration about these periods. He is teased, fretted, and uneasy, a little before the change and full, but when that takes place the appearances give way to more outrageous acts ; and, in defiance of his better principles, he is very apt to quarrel with almost every one that comes near him. This species of lunacy is of the knowing sort, since most, who are under its influence, believe themselves excessively clever 127 and shrewd, when labouring under the hallucination. Independently of all these considerations, I cannot admit that the moon exerts any influence in the production of cholera, since we meet with it at every period of her age and proceeding, independently of her increasing or decreasing, according to the state of the weather. In so far as the moon's influence extends to the regulation of the weather, I would agree to the supposition that it has some power over the disease. It is therefore over the state of the weather, in so far as this may be wet, moist, or dry, and not to any specific influence it exerts alone even although barometrical changes do not point it out, so far as refers to the tenuity of the air, or a deficit of electric matter. Under the last mentioned circumstances, we should certainly expect a great and overpowering disease to be produced by the sudden falling of the barometer, as we know takes place before hurricanes in many places of the world. We may meet with it falling more than an inch in a few hours, as has often occurred at the Mauritius, immediately before the bursting of storms, which prevail there in resistless fury, — yet no epidemic has manifested itself. In fact, the place remains healthy. I must, however, state that, after the last hurricane in 1834, there was much chin-cough amongst the children. I could enlarge much on this point but the instances adduced, will, I trust, be sufficient to account for the noninterposition of sol lunar influence, deficit of electricity, or tenuity of the air as being influential in the production of any epidemic. In fact, when such are prevailing the hurricanes in general make them more tractable, particularly after these have expended their fury, so long as the weather remains clear and dry ; when not so, the 128 noxious particles are not so rapidly carried off as when it is in a contrary state. If sol lunar influence had to do with the production of disease of this class, why should we not have it existing in every part of the world, and to the same extent, in many places where causes are favourable for their production, I mean as regards the state of the weather, this we know is not the case even from the earliest accounts of some of these places : — if we take the Mauritius as an example, we know that the disease did not shew itself to any extent there, before 1819. From that period to this, it has never prevailed as an epidemic, although a few solitary cases are occasionally met with in the summer season ; these are^ however, mainly attributable to the other sources from which I have stated the disease in question may arise, — such as eating indigestible substances, shell fish, the climate or malaria. Here then, as we have seen above we have the epidemic introduced in the first instance into the island — and I would now ask why it has not continued to prevail if it depended on sol lunar influence or a tenuity of the air, since there are few places where the barometer changes so much in a few hours ? As this, however, is not the case here, we have little hesitation in rejecting it as the cause of cholera, in any other part of the world. Sol lunar influence is a very convenient way of accounting for the rise and spread of such an epidemic as this, for it certainly does depend greatly on the state of the weather, and it must occur during some period of the month, as is evident enough ; none however, can tell that it is in consequence of the moon's influence that the disease is produced. If we divide the quarters of the moon's age, we will have three and a half days on either side of these points, then there comes to be a clear short space which may either be free or the reverse, 129 until we approach within a few days of the change or full. Now I repeat that this is a very convenient way to account for the presence of the disease ; but as we know that it often gives premonitory signs, for a few days, before it breaks out, by an irregularity of the bowels, and if we calculate from these appearances, we shall have it prevailing both under the influence of the full and change, or in the other quarters, although, I believe it has been said, that the attack prevails with more virulency at the time of the full. It is imagined that the supposition is nugatory and fallacious in the extreme ; although a convenient one perhaps for the purpose which it serves, I cannot admit it as in any way connected with the production of epidemic cholera. That cholera depends on the same cause as other epidemics, will appear evident when we consider that in those climates, in which the disease more regularly shews itself at certain periods of the year, we* have either dysentery, intermittent fever, cholera, or many others. One of these diseases predominating over the others. I think that this distinctly shews that the same cause determines, or brings into operation, the whole of them, as it may be in a major or minor degree of concentration. Do we not observe even during the prevalence of cholera, bowel complaints, or fevers, and this the more particularly, towards the close of the reign of the severe epidemic ?—? — these things occur even when the cholera suddenly disappears. From hence, I would draw the inference that the greater the concentration of the miasmatic or morbific principle, so much the more severe will be the leading or reigning disease. We see therefore, now, that the weather has much to do with this. as a cause. It is no argument against the opinion that the same kind of weather produces both these species, of disease. I answer 130 at once, and without scruple, that the morbific material from other causes is not present each year, to the same, extent, and that the weather is not always the same, although apparently so, there being frequently some deviation the one year from the other. " I will mention" says Dr. Kennedy. " That in the province of Guzu