;^fi«fe:.: BOSTON MEDICAL LIBRARY IN THE Francis A.Countway Library of Medicine BOSTON ^^ ^X ^1 e«^.^^^wc,^^?t4; EXPERIMENTS AND OBSERVATIONS ON THE GASTRIC JUICE, AND THE PHYSIOLOGY OF DIGESTION. Digitized by the Internet Archive in 2011 with funding from Open Knowledge Commons and Harvard Medical School http://www.archive.org/details/experimentsobserOObeau EXPERIMENTS AND OBSERVATIONS ON THE GASTRIC JUICE, AND THE PHYSIOLOGY OF DIGESTION. BY WILLIAM BEAUMONT, M.D. SURGEON IN THE UNITED STATES' ARMY. REPRINTED FROM THE PLATTSBURGH EDITION, WITH NOTES BY ANDREW COMBE, M.D. FELLOW OF THE ROYAL COLLEGE OF PHYSICIANS OF EDINBURGH ; PHYSICIAN EXTRAORDINARY TO THE QUEEN IX SCOTLAND, AND CONSULTING PHYSICIAN TO THE KING AND QUEEN OF THE BELGIANS. EDINBURGH: MACLACHLAN & STEWART, SOUTH BRIDGE ; AND SIMPKIN, MARSHALL & CO., LONDON. MDCCCXXXVIII. /3 a. 4 f / — i^^ PRINTED BY NEILL AND CO., OLD FISHMARKET, EDTNBQRGH. PREFACE BY THE EDITOR. The reasons which have induced me to reprint the present work from the American original, are, 1st, A strong sense of its inherent importance and of the numerous applications which may be made of the facts and principles developed in it to the pre- vention and cure of disease ; ^dly, Its comparative inaccessibility to the European physiologist from the difficulty which still exists of procuring it on this side of the Atlantic ; and, lastly. An earnest desire that the author should obtain that credit which is unquestionably due to his disinterested and indefa- tigable labours. The value of Dr Beaumonfs experiments consists partly in the admirable opportunities for observa- tion which he enjoyed, and partly in the candid and truth-seeking spirit in which all his inquiries seem to have been conducted. Two or three other cases have indeed occurred in which the cavity of the sto- jnach was laid open by external wounds, but in VI PREFACE BY THE EDITOR. none except that of Alexis St Martin, observed by Dr Beaumont, did perfect recovery take place while the opening remained unclosed. In all of them, death occurred in a longer or shorter time, without affording any opportunity of observing the pheno- mena of really healthy digestion. In St Martin, however, notwithstanding the severity of the wound, recovery was so complete that he continued for years (and, I believe, still continues) to lead a laborious life in the enjoyment of vigorous health, while diges- tion was as regular and effective as if no opening into the stomach had ever existed, or as if that once made had been entirely closed. For nearly eleven years after his accident, St Martin continued more or less under Dr Beaumont's observation, and during several years of that time lived in his house as a do- mestic servant, for the express purpose of being ex- perimented upon. So far, then, as opportunity for observation was concerned, nothing could surpass that enjoyed by Dr Beaumont. That Dr Beaumont eagerly and zealously availed himself of his unusual advantages, the following pages furnish ample evidence, and it would, I think, be difficult to point out any observer who excels him in devotion to truth, and freedom from the trammels of theory or prejudice. Among the disci- plined physiologists of Europe, a more systematic experimenter might certainly have been found, but PREFACE BY THE EDITOR. Vll in Dr Beaumont's instance, the absence of systema- tized inquiry — made too generally in support of a preconceived theory, and therefore apt to mislead as well as to instruct — is more than compensated by the implicit reliance which one feels can be placed on the accuracy and candour of his statements. Having no theory to support, and no favourite point to establish, Dr Beaumont tells plainly what he saw, and leaves every one to draw his own inferences, or where he lays down conclusions, he does so with a degree of modesty and fairness of which few perhaps in his circumstances would have been capable,* But, it may be said, singularly favourable as t)r Beaumont's opportunities were, he has made no ori- ginal discovery in the physiology of digestion. To a certain extent this is true, for in the proper sense of the word he has not made and does not claim to have made any discovery, but he has done what is at least equally essential for practical purposes. By separating the truth clearly and unequivocally from the numerous errors of fact and opinion with which it was mixed up, and thus converting into certain- * In proof of Dr Beaumont's disinterestedness in conducting the inquiry, I may mention that I have learned from private sources that the expenses attending the various series of experi- ments exceeded in amount L.700 Sterling, the whole of which was defrayed by himself, and for repayment of which he was ad- vised to apply to Congress, on the ground of the public being in- terested in the promotion of scientific discovery ; but although the American Treasury was at the time literally overflowing, the ap- plication was refused. Vlll PREFACE BY THE EDITOR. ties points of doctrine in regard to which positive proofs were previously inaccessible, he has given to what was doubtful or imperfectly known, a fixed and positive value, which it never had before, and which being once obtained, goes far to furnish us with a clear, connected, and consistent view of the general process and laws of digestion. Other physio- logists have attempted to effect the same end by expe- riments performed upon the lower animals, but these are open to so many forcible objections, that we can- not always adopt their conclusions, even where they seem to be most clearly deduced. Not to mention the cruelty inseparable from the performance of such experiments, the pain which the animal suflPers ne- cessarily disturbs the regularity of the function under examination, and in a greater or less degree vitiates the results. And even if this were not the case, the difference between the digestive organs in man and in the lower animals is so great, that it would often be unsafe to assume conclusions as applicable to the former which have been verified only in the latter. In perusing the present volume, it is proper to bear in mind the circumstances under which the ex- periments were made, and the account of them was written. Dr Beaumont was far from enjoying the leisure, resources, and scientific co-operation so easily accessible to the physiologists of any of our Euro-. PREFACE BY THE EDITOR. IX pean capitals. Stationed in a comparatively remote quarter in the exercise of his duties as an army sur- geon, and previously unaccustomed to minute phy- siological research, he conducted his inquiry under many minor disadvantages. When he came to pub- lish also, his want of experience in writing prevent- ed him from making the most of his materials, and doing that justice to himself which he might other- wise have easily accomplished. In the arrangement of his experiments, for example, Dr Beaumont has followed the order of time, and thus mingled many things together, where a more practised inquirer would have classified them according to the subjects in illustration of which they were performed, and thus given a greater unity of purpose to each of the different series of which they are composed. But al- though this defect diminishes the facility of access to the results, it by no means detracts from their in- trinsic value. On the contrary, the very absence of systematized arrangement leaves a character of even greater trust-worthiness attached to the individual observations than if the latter had been made under the influence of some prominent guiding principle, which might have given a bias to the mind. When preparing the following pages for the press, I took a good deal of trouble in an attempt to remedy the above defects of arrangement, but the original absence of method had led to such an inter- X PREFACE BY THE EDITOR. mixture of topics as to render their proper classifi- cation impossible, and I was obliged to give it up. I have, however, endeavoured to facilitate reference by prefixing to each chapter a short summary of its contents, and by adding illustrative notes wherever it could be done with advantage. To the substance of the text I have, of course, carefully adhered ; but I have taken the liberty of altering, and I trust improving, the arrangement of the table illustrative of the digestibility of different kinds of food, occur- ring at page 292, and of the " concluding Infe- rences^' at page 298. The object of both these al- terations was simply to present the different sub- jects in a more natural and instructive order than the author himself has done. As the first division of the work now stands, the reader will remark a considerable similarity between it and the corresponding part of a volume published by me about two years ago.* The similarity exists, so far as the physiological expositions are concerned, because the subjects treated of are nearly the same, and most of the doctrines advanced are peculiar to neither of us, but are those which have long been more or less firmly established ; and also because I naturally availed myself of Dr Beaumont's observa- tions, as the latest and most accurate, wherever I * The Physiology of Digestion considered in relation to the Principles of Dietetics, 2d edition. Edinburgh, 1837. PREFACE BY THE EDITOR. XI could turn them to account in confirming what was before doubtful, or correcting what he proved to be erroneous. But, except in the purely physiological ex- position of the subjects, there is a difference between us, corresponding to the different purposes for which we wrote. Dr Beaumont's sole object was to extend our knowledge of the physiology of digestion, without direct reference to any practical end. My chief aim, on the other hand, was to lay the foundation of a proper system of Dietetics, and to treat of the or- gans and physiology of digestion, only as bearing upon this point, and as the real basis on which all dietetic rules ought to rest. Accordingly, although we both treat of Mastication, Insalivation, Degluti- tion, Chymification, &c., Dr Beaumont limits him- self purely to a physiological exposition, while I treat of them, not only physiologically, but also with re- ference to the organization which executes them, and the means by which their healthy action may be most effectually promoted, preserved, or restored. But, while profiting by that gentleman's labours to enforce more authoritatively the practical truths which it was my chief object to inculcate, I have always been anxious to render him that ample measure of justice to which he is so eminently entitled ; and accordingly, in the preface to my book, I expressly mention, that, " in preparing the present volume for the press, I have derived the Xll PREFACE BY THE EDITOR. utmost advantage from a very valuable work by Dr Beaumont, an American writer, which, though scarcely at all known in this country, contains an authentic record of some of the most curious and instructive observations which have ever been made on the subject of Digestion. That excellent and enlightened physiologist had the rare good fortune to meet with a case in which an artificial opening into the stomach existed, through which he could see every thing that took place during the progress of healthy digestion ; and, with the most disinterest- ed zeal and admirable perseverance, he proceeded to avail himself of the opportunity thus afforded of advancing human knowledge, by engaging the pa- tient, at a heavy expense, to live with him for seve- ral years, and become the subject of numerous and carefully conducted experiments. Of the results thus obtained, I have not scrupled to make the freest and most ample use, — not from considering them as positively new (for even Dr Beaumont lays little claim to the merit of a discoverer), but because they come before us so entirely freed from the nu- merous sources of error and doubt which formerly impaired their value, that they can now, for the first time, be safely trusted as practical guides in the science of Dietetics. From Dr Beaumont's work also being still inaccessible to the British reader, it is a bare act of justice towards him, and also the PREFACE BY THE EDITOR. XIU best way of fulfilling the objects he had in view, to make its contents known as widely as possible ; for wherever they are known, they will be acknowledged to redound to his credit, not less as a man than as a philosopher."— (Preface, p. xxv.) So much, indeed, did I consider the republication of Dr Beaumon^s work as a matter of justice to him, that, had I not expected its appearance from some other quarter long ago, I would have undertaken the task at an earlier period, and, even now, I can account for the omission only by supposing that very few copies of the original have reached this country. Everywhere, both in British and foreign books, we meet with reference to, and often inac- curate extracts from it, but almost nowhere is it spoken of as if the work itself had been consulted. I trust then, that in now presenting it, I shall be con- sidered as rendering an acceptable service to British and Continental physiologists, as well as a pleasing act of justice to its deserving author. Actuated by the feeling that knowledge is valua- ble chiefly for the uses to which it may be applied, I have ventured to add a supplementary chapter, embodying a few of the practical conclusions which may be deduced from the experiments of Dr Beau- mont, but finding that, to do full justice to them, would both add to the size of the volume, and ne- cessarily involve a repetition of several topics already XIV PREFACE BY THE EDITOU. discussed in the work referred to, I have judged it better not to enter too largely upon this branch of the subject, particularly as the professional reader can deduce his own inferences for himself. I may, however, add, in reference to the table exhibit- ing the relative digestibility of different articles of diet, that its results ought to be received, not as certainties, but only as approximations to the truth. The rapidity of digestion is so much influenced by the quantity eaten, the degree of preparatory mas- tication, the amount of exercise, the mode of life, and state of health, that no positive conclusions on that point can be drawn, except where due attention has been paid to all these modifying circumstances. In the following experiments, however, Dr Beau- monfs chief aim was to ascertain the nature and laws of the digestive process, and his observations on the comparative digestibility of different sub- stances, were thus too incidental to be relied upon as minutely accurate ; but in a general way they are well worthy of attention. In the second edition of the " Physiology of Di- gestion" I ventured to suggest, that some of our scientific associations, such as the Royal Society or British Association, would do science a service and themselves an honour, by using their influence and means to have St Martin brought over to this coun- try, and the remainder of the subject fully investi- PREFACE BY THE EDITOR. XV gated under the direction of a committee of their number. An opportunity of this kind may never occur again, and it will be a source of lasting re- gret, and even of merited reproach, if it be allowed to pass away without being turned to the best pos- sible account. If the suggestion now thrown out shall ever be acted upon, special care should be taken not to injure St Martin's health by withdrawing him entirelv from his accustomed diet and mode of Kfe, otherwise the whole value of the experiment may be lost, — the object being to ascertain the laws and con- ditions of HEALTHY DIGESTION. Edinburgh, April 1838. CONTENTS. Author's Prefac e, . . . . . 1-3 CHAPTER I. HISTORY OF THE CASE OF ALEXIS ST MARTIN. St Martin's Stomach perforated by a musket-shot — Situation and nature of the wound — His treatment and recovery — External opening into the stomach remains unclosed — Mode of extracting gastric juice through the opening — Extraordinary facilities presented for experimenting on digestion, by introducing and withdrawing food through the opening, and observing its changes — Woodcuts repre- senting the appearance of the wound after recovery, and the valve by which the opening is filled up, . • 7-23 CHAPTER II. OF ALIMENT. Man an omnivorous animal — Nature of animal food — The ulti- mate principles of aliment the same, whether derived from animals or vegetables — The action of the stomach on food always the same — The quantity of nutriment re- quired varies according to circumstances — The quality is also important — Variety is required — Table of digesti- bility of various substances — Animal more quickly di- gested than vegetable food — Minuteness of division in- fluential on digestion — Fish easily digested — Condiments not essential — Drink necessary — Effect of Wine — Quan- tity more influential than quality, .... 24.42 XVlll CONTENTS. CHAPTER III. OF HUNGER AND THIRST. Hunger — Its exciting cause — Different theories of— The Au- thor's theory of hunger — Thirst and its causes — Objec- tions to the Author's theory of hunger, . . . 43-51 Note by the Editor, 51-53 CHAPTER IV. OF SATISFACTION AND SATIETY. Quantity of food required — Satiety not a proper guide — The first feeling of satisfaction is the true indication — Gastric juice secreted in relation to this indication, . . 54-57 CHAPTER V. MASTICATION, INSALIVATION, AND DEGLUTITION. Uses of mastication — Nature and use of saliva — Saliva not essential to digestion — Mastication essential as a meaaas of dividing food into minute portions — Deglutition ought to be slow, as the stomach admits only of slow disten- tion, 58-63 Note by the Editor, 63 CHAPTER VI. OF DIGESTION BY THE GASTRIC JUICE. Chymification — Agents of. — Spallanzani's theory of Diges- tion— Common opinions regarding the gastric juice — Gas- tric juice has a solvent power — Analysis of — Composition of — Its action is purely chemical — Gastric juice described — Its quantity proportioned to wants of the system — Its secretion and action begin on the contact of food— Evils of frequent eating explained — Gastric juice supplied to all the food at once when the latter is not in excess — Old and new food mix — Effects of exercise on digestion — Bile not essential to chymification — Chyme, its nature and pro- gress— Montegre's theory of digestion — Smith's and Jack- son's theories — General remarks, .... 64-93 CONTENTS, XIX CHAPTER VII. OF THE APPEARANCE OF THE VILLOUS COAT, AND OF THE MOTIONS OF THE STOMACH. Appearance of the villous coat — Gastric Papillae — Healthy aspect of the villous coat — Its aspect in disease — Motions in the stomach — Effects of — Order of contraction in the muscular fibres of the stomach — Passage of the chyme out of the stomach, 94-10? CHAPTER VIII. OF CHYLIFICATION, AND THE USES OF THE BILE AND • PANCREATIC JUICE, Passage of chyme into the duodenum — and there converted into chyle by the agency of the bile and pancreatic juice — Chyle always the same in health — Changes occurring in the duodenum, ....... 108-116 EXPERIMENTS AND OBSERVATIONS. First Series, 117-14! Second Series, 124-166 Third Series, 167-242 Note by the Editor, 243-243 Microscopic Examinations, 245-246 Fourth Series, 247-255 Note by the Editor, . 253-255 Experiments, &c. 255-291 Table shewing the Mean Time of Digestion of tlie different Articles of Diet, naturally, in the Stomach, and artificially in Vials, on a Bath, ...... 292-29S Table shewing the Temperature of the Interior of the Stomach in different Conditions, taken in different Seasons of the Year, and at various times of the Day, from 5 o'clock in the Morning till 12 o'clock at night, . . . 295-296 Inferences from the foregoing Experiments and Observa- tions, 298-303 Concluding Remarks by the Editor, . . . . 303-328 PREFACE. The present age is prolific of works on physiology ; therefore in offering to the public another book relative to an important branch of this science, it will, perhaps, be necessary to assign my motives. They are, first, a wish to comply with the repeated and urgent solicitations of many medical men who have become partially acquainted with the facts and observa- tions it is my intention to detail ; men in whose judg- ment I place confidence, and who have expressed their conviction of the deep importance of the experiments, the result of which I mean herewith to submit to the public : secondly, (and it is that which mainly influences me,) my own firm conviction that medical science will be forwarded by the publication. I am fully aware of the importance of the subject which these experiments are intended to illustrate, as well in a pathological as in a physiological point of view ; and I am therefore willing to risk the censure or neglect of critics, if I may be permitted to cast my mite into the treasury of knowledge, and to be the means, either directly or in- ^ PREFACE. directly, of subserving the cause of truth, and amelio- rating the condition of suffering humanity. I make no claim to originality in my opinions, as it re- spects the existence and operation of the gastric juice. My experiments confirm the doctrines (with some modi- fications) taught by Spallanzani, and many of the most enlightened physiological writers. They are experiments made in the true spirit of inquiry, suggested by the very extraordinary case which gave me an opportunity of making them. I had no particular hypothesis to support ; and I have therefore honestly recorded the result of each experiment exactly as it occurred. The reader will perceive some slight seeming discre- pancies, which he may find it difficult to reconcile ; but he will recollect that the human machine is endowed with a vitality which modifies its movements in different states of the system, and probably produces some diversity of effects from the same causes. I had opportunities for the examination of the interior of the stomach, and its secretions, which have never be- fore been so fully offered to any one. This most im- portant organ, its secretions and its operations, have been submitted to my observation in a very extraordinary man- ner, in a state of perfect health, and for years in succes- sion. I have availed myself of the opportunity afforded by a concurrence of circumstances which probably can never again occur, with a zeal and perseverance proceed- ing from motives which my conscience approves ; and I now submit the result of my experiments to an enlight- i PREFACE. 3 ened public, who, I doubt not, will duly appreciate the truths discovered, and the confirmation of opinions which before rested on conjecture. I submit a body of facts which cannot be invalidated. My opinions may be doubted, denied, or approved, ac- cording as they conflict or agree with the opinions of each individual who may read them ; but their worth will be best determined by the foundation on which they rest — the incontrovertible facts. I avail myself of this opportunity to make my grateful acknowledgments to Doctor Joseph"^ Lovell, Surgeon- General of the United States' Army, (to whom I am un- der obligations for personal kindness and official exer- tions in affording facilities for prosecuting the experi- ments ;) — to Professors Silliman, Knight, Ives, and Hub- bard, of Yale College ; Dunglison, of the Virginia Uni- versity, and Sewal, Jones, Henderson, and Hall, of Columbian College, for their unsolicited friendship ; for the interest which they have taken in the experiments, and for the generous encouragement which they have given to the proposed publication. To Doctor Samuel Beaumont, of Plattsburgh, N. Y., I am particularly in- debted, for the assistance which he has rendered me in arranging and preparing my notes for the press. Plattsburgh, 1833. PRELIMINARY OBSERVATIONS. ( 7 ) CHAPTER I. HISTORY OF THE CASE OF ALEXIS ST MARTIN. St Martin's Stomach perforated by a musket-shot — Situation and nature of the wound — His treatment and recovery — Ex- ternal opening into the stomach remains unclosed — Mode of extracting gastric juice through the opening — Extraordinary facilities presented for experimenting on digestion, by intro- ducing and withdrawing food through the opening, and ob- serving its changes — Woodcuts representing the appearance of the wound after recovery, and the valve by which the opening is filled up. The experiments which follow were commenced in 1825, and have been continued, with various interrup- tions to the present time, (1833). The opportunity for making them was afforded to me in the following way. Whilst stationed at Michillimackinac, Michigan Terri- tory, in 1822, in the military service of the United States, the following case of surgery came under my care and treatment. Alexis St Martin, who is the subject of these experi- ments, was a Canadian, of French descent, at the above mentioned time about eighteen years of age, of good con- stitution, robust and healthy. He had been engaged in the service of the American Fur Company, as a voyageur, and was accidentally wounded by the discharge of a mus- ket, on the 6th of June 1822. 8 CASE OF ALEXIS ST MARTIN. The charge, consisting of powder and duck-shot, was received in the left siae of the youth, he being at a dis- tance of not more than one yard from the muzzle of the gun. The contents entered posteriorly, and in an oblique direction, forward and inward, literally blowing off inte- guments and muscles of the size of a man's hand, frac- turing and carrying away the anterior half of the sixth rib, fracturing the fifth, lacerating the lower portion of the left lobe of the lungs, the diaphragm, and perforating the stomach. The whole mass of materials forced from the muskety together with fragments of clothing and pieces of frac- tured ribs, were driven into the muscles and cavity of the chest. I saw him in twenty-five or thirty minutes after the accident occurred, and, on examination, found a portion of the lung as large as a turkey's egg, protruding through the external wound, lacerated and burnt ; and imme- diately below this, another protrusion, which, on further examination, proved to be a portion of the stomach, la- cerated through all its coats, and pouring out the food he had taken for his breakfast, through an orifice large enough to admit the forefinger. In attempting to return the protruded portion of the lung, I was prevented by a sharp point of the fractured rib, over which it had caught by its membranes ; but by raising it with my finger, and clipping off the point of the rib, I was able to return it into its proper cavity, though it could not be retained there, on account of the inces« CASE OF ALEXIS ST MARTIN. 9 sant efforts to cough. The projecting portion of the stomach was nearly as large as that of the lung. It passed through the lacerated diaphragm and external wound, mingling the food with the bloody mucus blown from the lungs. , After cleansing the wound from the charge and other extraneous matter, and replacing the stomach and lungs as far as practicable, I applied the carbonated fermenting poultice, and kept the surrounding parts constantly wet with a lotion of muriate of ammonia and vinegar ; and gave internally the aq. acet. am. with camphor, in liberal quantities. Under this treatment a strong reaction took place in about twenty-four hours, accompanied with high arterial excitement, fever, and marked symptoms of inflammation of the lining membranes of the chest and abdomen, great difficulty of breathing, and distressing cough. He was bled to the amount of eighteen or twenty ounces, and took a cathartic. The bleeding reduced the arterial ac tion, and gave relief. The cathartic had no effect, as it escaped from the stomach through the wound. On the fifth day a partial sloughing of the integu- ments and muscles took-place. Some of the protruded portions of the lung, and lacerated parts of the stomach, also sloughed, and left a perforation into the stomach, plainly to be seen, large enough to admit the whole length of my fore-finger into its cavity ; and also a pas- sage into the chest, half as large as my fist, exposing to 10 CASE OF ALEXIS ST MARTIN. view a part of the lung, and permitting the free escape of air and bloody mucus at every respiration. A violent fever continued for ten days, running into a typhoid type, and the wound became very fcetid. On the eleventh day, a more extensive sloughing took place, the febrile symptoms subsided, and the whole sur- face of the wound assumed a healthy and granulating ap- pearance. For seventeen days, all that entered his stomach by the oesophagus, soon passed out through the wound ; and the only way of sustaining him was by means of nutri- cious injections per anum, until compresses and adhesive straps could be applied so as to retain his food. During this period no alvine evacuations could be obtained, al- though cathartic injections were given, and various other means were adopted to promote them. In a few days after firm dressings were applied, and the contents of the stomach retained, the bowels became gradually excited, and, with the aid of cathartic injec- tions, a very hard, black, fcetid stool was procured, fol- lowed by several similar ones ; after which the bowels became quite regular, and continued so. The cataplasms were continued until the sloughing was completed, and the granulating process fully established ; and were af- terwards occasionally resorted to, when the wound be- came ill conditioned. The aq. acet. am. with camphor was also continued for several weeks, in proportion to the febrile symptoms and the foetid condition of the wound. CASE^OF ALEXIS ST MARTIN. 11 No sickness nor unusual irritation of the stomach, not even the slightest nausea, was manifest during the whole time ; and after the fourth week, the appetite became good, digestion regular, the alvine evacuations natural, and all the functions of the system perfect and natural. By the adhesion of the sides of the protruded portions of the stomach to the pleura costalis and the external wound, a free exit was aflPorded to the contents of that organ, and effusion into the abdominal cavity was thereby prevented. Cicatrization and contraction of the external wound commenced on the fifth week ; the stomach became more firmly attached to the pleura and intercostals, by its ex- ternal coats ; but shewed not the least disposition to close its orifice ; this (the orifice) terminated as if by a natu- ral boundary, and left the perforation, resembling, in all but a sphincter, the natural anus, with a slight prolapsus. ^' Whenever the wound was dressed, the contents of the stomach would flow out, in proportion to the quantity recently taken. If the stomach happened to be empty, or nearly so, a partial inversion would take place, unless prevented by the application of the finger. Frequently in consequence of the derangement of the dressing, the inverted part would be found of the size of a hen's egg. No difficulty, however, was experienced in reducing it by gentle pressure with the finger, or a sponge wet with cold water, neither of which produced the least pain. The annexed figure represents the protruded portion. AAAAA, are the folds or rugae of the inner surface of 12 CASE OF ALEXIS ST MARTIN. the stomach ; BBB are the interstices filled with mu- cous substance ; C shews the situation of the nipple. In the seventh week, exfoliation of the ribs, and a separation of their cartilaginous ends, began to take place. The sixth rib was denuded of its periosteum for about two inches from the fractured part, so that I was obliged to amputate it about three or four inches from its arti- culation with the rib. This I accomplished by dissect- ing back the muscles, securing the intercostal artery, and sawing off the bone with a very fine narrow saw, made for the purpose, introduced between the ribs, without in- jury to the neighbouring parts. Healthy granulations soon appeared, and formed soundly over the amputated CASE OF ALEXIS ST MARTIN. 13 end. About half the inferior edge of the fifth rib exfol- iated, and separated from its cartilage. After the removal of these pieces of bone, I attempted to contract the wound, and close the perforation of the stomach, by gradually drawing the edges together with adhesive straps, laid on in a radiated form. The circumference of the external wound was at least twelve inches, and the orifice in the stomach nearly in the centre, two inches below the left nipple, on a line drawn from this to the point of the left ilium. To retain his food and drinks, I kept a compress and tent of lint, fitted to the shape and size of the perforation, and confined there by adhesive straps. After trying all the means in my power for eight or ten months to close the orifice, by exciting adhesive in- flammation in the lips of the wound, without the least appearance of success, I gave it up as impracticable in any other way than that of incising and bringing them together by sutures ; an operation to which the patient would not submit. By the sloughing of the injured portion of the lung, a cavity was left as large as a common sized tea cup, from which continued a copious discharge of pus for three months, when it became filled with healthy granulations, firmly adhering to the pleura, and soundly cicatrized over that part of the wound. Four months after the injury was received, an abscess formed about two inches below the wound, nearly over the cartilaginous ends of the first and second false ribs. 14 CASE OF ALEXIS ST MARTIN. very painful, and extremely sore, producing violent symp- tomatic fever. On the application of an emollient poul- tice, it pointed externally. It was then laid open to the extent of three inches, and several shot and pieces of wad extracted. After which a gum -elastic bougie could be introduced three or four inches in the longitudinal di- rection of the ribs, towards the spine. Great pain and soreness extended from the opening of the abscess, along the track of the cartilaginous ends of the false ribs, to the spine, with a copious discharge from the sinus. In five or six days, there came away a cartilage, one inch in length. In six or seven days more, another, an inch and a half long ; and in about the same length of time, a third, two inches long, were discharged. And they continued to come away every five or six days, un- til Jive were discharged from the same opening, the last three inches in length. They were all entire, and evi- dently separated from the false ribs. The discharge, pain, and irritation, during the four or five weeks these cartilages were working out, greatly reduced the strength of the patient, produced a general febrile habit, and stopped the healing process of the ori- ginal wound. Directly after the discharge of the last cartilage, in- flammation commenced over the lower end of the ster- num, which, by the usual applications, terminated in a few days in a large abscess, and from which, by laying it open two inches, I extracted another cartilage, three inches in length. The inflammation then abated ; and CASE OF ALEXIS ST MARTIN. 15 in a day or two another piece came away, and the dis- charge subsided. To support the patient under all these debilitating cir- cumstances, I administered wine, with diluted muriatic acid, and thirty or forty drops of the tincture of assafoe- tida, three times a-day ; which appeared to produce the desired eflPect, and very much improved the condition of the wound. On the third of January 1823, 1 extracted another cartilage from the opening over the sternum, an inch and a half long ; and on the fourth another, two inches and a half in length, an inch broad at one end, and narrowing to less than half an inch at the other. This must have been the ensiform cartilage of the sternum. After this the sinus closed, and there was no return of inflammation. From the month of April 1823, at which time he had so far recovered as to be able to walk about and do light work, enjoying his usual good appetite and digestion, he continued with me, rapidly regaining his health and strength. By the 6th of June 1 823, one year from the time of the accident, the injured parts were all sound, and firmly cicatrized, with the exception of the aperture in the sto* mach and side. This continued much in the same situ- ation as it was six weeks after the wound was received. The perforation was about two and a half inches in cir- cumference, and the food and drinks constantly exuded, unless prevented by a tent, compress and bandage. From this time he continued gradually to improve in 16 CASE OF ALEXIS ST MARTIN. health and strength, and the newly formed integuments over the wound became firmer and firmer. At the point where the lacerated edges of the muscular coat of the stomach and intercostal muscles met and united with the cutis vera, the cuticle of the external surface and the mucous membrane of the stomach approached each other very nearly. They did not unite, like those of the lips, nose, &c. but left an intermediate marginal space, of ap- preciable breadth, completely surrounding the aperture. This space is about a line wide ; and the cutis and ner- vous papillae are unprotected, as sensible and irritable as a blistered surface abraded of the cuticle. This condi- tion of the aperture still continues, and constitutes the principal and almost only cause of pain or distress expe- rienced from the continuance of the aperture, the intro- duction of instruments, &c. in the experiments, or the exudation of fluids from the gastric cavity. Frequent dressings with soft compresses and bandages were necessarily applied, to relieve his suffering and retain his food and drinks, until the winter of 1 823-4. At this time, a small fold or doubling of the coats of the stomach appeared forming at the superior margin of the orifice, slightly protruding, and increasing till it filled the aper- ture, so as to supersede the necessity for the compress and bandage for retaining the contents of the stomach. This valvular formation adapted itself to the accidental orifice, so as completely to prevent the efflux of the gas- tric contents when the stomach was fu'l, but was easily depressed with the finger. CASE OF ALEXIS ST MARTIN, 17 '' I'he annexed wood-cut represents the ordinary appear- ance which the wound then presented, the aperture being filled with the valve. A A A A indicate the circumference and edge of the aperture, within which the valve is seen. B shews the attachment of the latter to the upper part of the aperture. C, the nipple. D, the anterior portion of the breast. E, the scar where the opening was made with the scalpel, and the cartilages taken out. FFFF, cicatrix of the original wound around the aperture. In the spring of 1824 he had perfectly recovered his natural health and strength; the aperture remained; 18 CASE OF ALEXIS ST MARTIN. and the surrounding wound was firmly cicatrized to its edges. In the month of May 1 825, 1 commenced my first se- ries of gastric experiments with him, at Fort Mackinac? Michigan Territory. In the month of June following, I was ordered to Fort Niagara, N. Y. where, taking the man with me, I continued my experiments until August. Part of these experiments were published in 1826, in the 29th number of the Philadelphia " Medical Recorder," conducted by Doctor Samuel Calhoun. About this time (August 1825), I took St Martin with me to Burlington, Vermont, and from thence to Plattsburgh, New York. From the latter place he returned to Canada, his native place, without obtaining my consent. Being unable to ascertain the place of his resort, I gave him up as a lost subject for physiological experiments, and returned to my post at the west again. I did not, however, remit my efforts to obtain information of his place of residence and condition. He remained in Canada four years, during which pe- riod he married, and became the father of two children ; worked hard to support his family ; and enjoyed robust health and strength. In 1825, as he has informed me, he engaged with the Hudson Bay Fur Company, as a voyageur to the Indian country. He went out in 1827, and returned in 1828 ; and subsequently laboured hard to support his family until 1829. Accidentally learning about this time where he was, and that he enjoyed perfect health, I made arrangements CASE OF ALEXIS ST MARTIN. 19 with the agents of the American Fur Company, who an- nually visit Canada for the purpose of procuring voyageurs, to find and engage him for my service, if practicable. After considerable difficulty, and at great expense to me, they succeeded hi engaging him, and transported him from Lower Canada, with his wife and two children, to me, at Fort Crawford, Prairie du Chien, Upper Missis- sippi, a distance of nearly two thousand miles, in August 1829. His stomach and side were in a similar condition as when he left me in 1825. The aperture was open, and his health good. The appearance which is presented when the valve was pushed back is shewn in the above figure. AAA, are the edges of the aperture. B indicates the cavity of the stomach as seen when the valve is depressed. C, the valve itself. EEE, the cicatrix of the original wound. F, the nipple. 20 CASE OF ALEXIS ST MARTIN. He now entered my service, and I commenced another series of experiments on the stomach and' gastric fluids? and continued them, interruptedly, until March 1831*;> During this time, in the intervals of experimenting, he performed all the duties of a common servant, chopping wood, carrying burthens, &c, with little or no suffering or inconvenience from his wound. He laboured constantly, became the father of more children, and enjoyed as good health and as much vigour as men in general. He sub- sisted on crude food, in abundant quantities, except when on prescribed diet, for particular experimental purposes, and under special observance. In the spring of 1831, circumstances made it expedient for him to return with his fgimily from Prairie du Chien to Lower Canada again. I relinquished his engagements to me for the time, on a promise that he would return when required, and gave him an outfit for himself, wife, and children. They started in an open canoe, via the Mississippi, passing by St Louis, Mo. ; ascended the Ohio river ; then crossed the state of Ohio, to the Lakes ; and descended the Erie, Ontario, and the River St Law- rence, to Montreal, where they arrived in June. He re- mained in Canada with his family until October 1832, in good health, and at hard labour. He was in the midst of the cholera epidemic, at the time it prevailed, and passed through Canada, and withstood its ravages with impunity, while hundreds around him fell sacrifices to its fatal influence. • In November 1832, he again engaged himself to me ■CASE OF ALEXIS ST MARTIN. 21 for twelve months, for the express purpose of submitting to another series of experiments. He joined me at Plattsburgh, N. Y., and travelled with me to the city of Washington, where, with the facilities afforded by ihe head of the Medical Department, the experiments were continued upon him from November 1832, to March 1833. During the whole of these periods, from the spring of 1824 to the present time, he has enjoyed general good _ health, and perhaps suffered much less predisposition to disease than is common to men of his age and circum- stances in life. He has been active, athletic and vigo- rous ; exercising, eating and drinJcing like other healthy and active people. For the last four months, he has been unusually plethoric and robust, though constantly sub- jected to a continued series of experiments on the inte- rior of the stomach ; allowing to be introduced or taken out at the aperture different kinds of food, drinks, elastic catheters, thermometer tubes, gastric juice, chyme, &c. almost daily, and sometimes hourly. Such have been this man's condition and circumstan- ces for several years past ; and he now enjoys the most perfect health and constitutipnal soundness, with every function of the system in full force and vigour. , , Mode of extracting the Gastric Juice. — The usual me- thod of extracting the gastric juice, for experiment, is by placing the subject on his right side, depressing the . valve within the aperture, introducing a gum-elastic tube, of the size of a large quill, five or six inches into the sto- 22 CASE OF ALEXIS ST MARTIN. mach, and then turning him on the left side, until the orifice becomes dependent. In health, and when free from food, the stomach is usually entirely empty, and contracted upon itself. On introducing the tube, the fluid soon begins to flow, first hydrops, then in an inter- rupted, and sometimes in a short continuous stream. Moving the tube about, up and down, or backwards and forwards, increases the discharge. The quantity of fluid ordinarily obtained is from four drachms to one and a half or two ounces, varying with the circumstances and con- dition of the stomach. Its extraction is generally attend- ed by that peculiar sensation at the pit of the stomach, termed sinking, with some degree of faintness, which ren- ders it necessary to stop the operation. The usual time of extracting the juice is early in the morning, before he has eaten, when the stomach is empty and clean. On laying him horizontally on his back, pressing the hand upon the hepatic region, agitating a little, and at the same time turning him to the left side, bright yellow bile appears to flow freely through the pylorus, and passes out through the tube. Sometimes it is found mixed with the gastric juice, without this operation. This is, however, sel- dom the case, unless it has been excited by some other cause. The chymous fluids are easily taken out by depressing the valve within the aperture, laying the hand over the lower part of the stomach, shaking a little, and pressing upwards. In this manner, any quantity necessary for ex- amination and experiment can be obtained. CASE-OF ALEXIS ST MARTIN. 23 Valve. — The valve mentioned above, is formed by a slightly inverted portion of the inner coats of the stomach fitted exactly to fill the aperture. Its principal and most external attachment is at the upper and posterior edge of the opening. Its free portion hangs pendulous, and fills the aperture when the stomach is full, and plays up and down, simultaneously with the respiratory muscles, when empty. On pressing down the valve when the stomach is full, the contents flow out copiously. When the stomach is nearly empty, and quiescent, the interior of the cavity may be examined to the depth of five or six inches, if kept distended by artificial means ; and the food and drinks may be seen entering it, if swallowed at this time, through the ring of the oesophagus. The perforation through the walls of the stomach is about three inches to the left of the cardia, near the left superior ter- mination of the great curvature. When entirely empty, the stomach contracts upon itself, and sometimes forces the valve through the orifice, together with an additional portion of the mucous membrane, which becomes com- pletely inverted, and forms a tumour as large as a hen's egg. After lying on the left side, and sleeping a few- hours, a still larger portion protrudes, and spreads out over the external integuments, five or six inches in cir- cumference, fairly exhibiting the natural rugge, villous membrane, and mucous coat, lining the gastric cavity. This appearance is almost invariably exhibited in the morning, before rising from his bed. ( 24 ) CHAPTER II. OF ALIMENT. Man an omnivorous animal — Nature of animal food — The ulti- mate principles of aliment the same, whether deriA^ed from animals or vegetables — The action of the stomach on food always the same — The quantity of nutriment required varies according to circumstances — The quality is also important — Variety is required — Table of digestibility of various sub- stances— Animal more quickly digested than vegetable food — Minuteness of division influential on digestion — Fish easily digested — Condiments not essential — Drink necessary — Effect of Wine — Quantity more influential than quality. Man is said to be an omnivorous animal, destined to procure his food from both the animal and vegetable kingdoms. The inhabitant of temperate climates is unquestionably so. It would be interesting to ascertain by experiment whether he would be sustained by habit from infancy, on the productions of either of these grand divisions. If the result should be favourable to the de- monstration of this proposition, though it might stiU more unsettle the opinions of physiologists, it would be an evi- dence of this truth, that man is a creature of habit and circumstance, carrying about him the effects of primeval disobedience, destined not only to earn his food by his own exertions, but to partake of such as the climate in which he resides may supply to him. Approximating to this are the habits of people of different quarters of the world — those of Asia, who live almost exclusively on ve- NATURE OF ANIMAL FOOD. 25 getable and farinaceous food, and those of the northern regions of America, who derive their food principally from fish, oil, and flesh. .Other substances have sometimes been used as aliment: and Professor Dunglison mentions, on the authority of Humboldt, that the Ottomaques, a tribe of Indians of South America, are in the habit of using " an unctuous earth, or a species of pipe-clay,'" as an article of diet. Whether nutriment can be supplied by such articles alone, is extremely problematical. In all countries, some persons are found who are in the constant habit of eating large quantities of clay, chalk, slate, stone, &c. Such practices may be regarded as evidence, if not of a diseased, at least of a vitiated appetite ; though it often happens that alkaline and absorbent substances are used medicinally with advantage, particularly where much aci- dity of the stomach prevails. As it respects the inhabitants of Europe and their American descendants, as well as most other natives of temperate climates, it is well known that they derive their nourishment from both the animal and vegetable kingdoms. The facility of digestion of different articles of -diet, and the quantity of nutrient principles which they con- tain, have been subjects of some discrepance of opinion among physiologists. They have, however, settled down into a belief, probably as near the truth as practicable, that animal food is more readily assimilated, and affords 26 NATURE OF ANIMAL FOOD. more nutrition in a given quantity, than vegetable or farinaceous food. Animal food has been divided into fibrine, gelatine, and albumen, and a comparison drawn between their de- grees of digestibility. But it will occur to every one at all acquainted with the subject, that almost every portion of animal food contains an admixture of all these princi- ples, and it is consequently very difficult to come to a correct conclusion. The truth is, there can be no gene- ral rule on this subject. The facility of digestion is mo- dified by so many circumstances, as health, disease, idio- syncracy, habit, and preparation of food, that a rule which would apply in one case would be incorrect in another. It depends more upon other distinctions than upon those relating to the chemical composition of the food. Albu- men (one of these chemical divisions), if taken into the stomach, either very slightly or not at all coagulated, is perhaps as rapidly chymified as any article of diet we possess. If perfectly formed into hard coagulse, by heat or otherTvise, and swallowed in large solid pieces, it experi- ences a very protracted digestion. The reason is obvi- ous. In the first case, the albumen becomes finely coa- gulated, and divided in the stomach ; in the second, it is less susceptible of subdivision from its hardness. Fibrine and gelatine are affected in the same way. If tender and finely divided, they are disposed of readily ; if in large and solid masses, digestion is proportionably retarded. Minuteness of division and tenderness of fibre are the two grand essentials for speedy and easy digestion. By re- - ULTIMATE PRINCIPLES OF NUTRIMENT. 27 ferring to my experiments, it will be seen that those ar- ticles of diet which were submitted to the action of the gastric juice, either artificially when out of the stomach, or in the stomach by natural process, were dissolved in proportion to the fineness of their division or their soli- dity— the one rapidly, and the other slowly. The digestion of animal and vegetable diet requires the same process, though one may afford a larger pro- portion of the nutrient principle than the other. Gene- rally speaking, vegetable aliment requires more time, and probably greater powers of the gastric organs, than ani- mal. Its digestibility is, however, dependent upon the same laws as those that govern the solution of animal food ; and it is facilitated by division and tender- ness. The ultimate principles of nutriment are probably al- ways the same, whether obtained fi'om animal or vege- table diet. It was said by Hippocrates, that " there are many kinds of aliments, but that there is at the same time but one aliment." This opinion has been contested by most modern physiologists ; but I see no reason for scepticism on this subject. Some imperfect experiments which I instituted on the operations of the hepatic and pancreatic juices, and which will be found in a subse- quent part of this volume, tend to throw some light on the subject. Chyme was submitted to the action of these fluids, and they invariably produced similai' effects A fluid was separated, varying slightly in colour, but of the same apparent consistence and identity ; and was increased 28 ACTION OF THE STOMACH ON FOOD* or lessened in proportion to the quality of the food of which the chyme was formed. Whether this fluid was or was not imperfectly formed chyle, is a matter of opi- nion only. The circulating fluids of the system are al- ways nearly the same in health, and that which goes to supply and replenish them, should consequently possess the same invariable properties. Chyle, after its separa- tion in the intestines, is probably further changed and perfected by the action of the lacteal absorbents and sanguiferous vessels, before it is completely assimilated. Chyme, from which this nutrient principle is obtained, is a compound of gastric juice and aliment. It may be re- garded as a gastrite of whatever it is combined with, va- ried according to the kind of aliment used. The perfect chyle, or assimilated nutriment, probably contains the elements of all the secretions of the system ; such as bone, muscle, mucus, saliva, gastric juice, &c. &c., which are separated by the action of the glands, the sanguife- rous and other vessels of the system. The action of the stomach, and its fluids, on aliment, is believed to be sui generis, invariably the same, in health, on all kinds. And yet it is contended by Paris, and obliquely hinted by some other modern physiologists, that as animal food " possesses a composition analogous to that of the structure it is designed to supply," it " re- quires little more than division and depuration," &c. It is singular that sensible men, and men of science, can allow themselves to be led to such erroneous conclusions, and w^ill not perceive a simplicity and uniformity in the ACTION OF THE STOMACH ON FOOD. 2Q process of digestion, as well as in all the other operations of nature. That the active solvent of the stomach should produce the same effect on all alimentary substances, is no more wonderful than that caloric should liquefy all kinds of matter. In both cases it only requires a longer or shorter continuance, or more or less concentrated ac- tion, of the agent, to produce the same effect. If animal food is only to be divided and depurated, blood, which is an elementary part of the body, would require no change in the stomach. But it is perfectly idle to talk in this way. The most innutritious vegetable and the most ani- malized substance, require the same action of the gastric solvent, as the reader will find amply demonstrated in the following experiments. It is true that one may be dis- posed of with ease, and the other with difficulty ; but this is not always, nor indeed often, in a direct ratio to their respective proportions of nutrient principles. An innu- tritious diet may be disposed of as easily, the circum- stances of divisibility and tenderness of fibre being equal, as a nutritious one. I do not believe that the one re- quires a more " complicated series of decompositions and recompositions " than the other ; nor that the chyle from animal aliment is more highly " animalized" than that from the poorest diet we possess. The " digestive fever," or the excitement that follows the digestion of animal food, is the effect, not of a different kind of stimulus, but of the introduction of a greater quantity of chyle, or the nutritive principle of food, into the circulating fluids. It excites the system precisely in the same manner as ardent 38 QUALITY OF NUTRIMENT REQUIRED. spirits, or other stimulus does, with the exception, that its effects are more permanent. The quantity of nutriment required by different indi- viduals, is as various as the individuals who partake of it. As a general rule, it may be said that persons who do not exercise much, require less nutritious diet than those who are in the habit of constant labour. What would be a natural supply in one, would be excess in another. With labouring persons, much of the excess is carried off by perspiration ; and probably a great deal of nervous energy is wasted by laborious occupations, which re- quires to be replenished by the nutrient principles of aliment. This is a subject, however, on which we can only offer conjecture ; for it is difficult to argue on a point of which we know so little. Young people who are grow- ing, require more nutriment in proportion to their size, than those who have arrived at adult age.* The quality of nutriment is a matter of considerable importance in dietetic regulations. Bulk is, perhaps, * The rapidity and extent of waste occurring under certain cir- cumstances, have been ably exhibited by Dr Southwood Smith in the second volume of his Philosophy of Health (p. 393). Dr Smith weighed eight of the men employed in feeding the fires of the Phoenix Gas Company in London, before they began and after finishing their work, which latter lasted one hour. The tempera- ture of the atmosphere at the time was 60*', and the barometer stood at 29.25. The loss sustained during that short time amount- ed to 2 lb. 8 oz. in the lowest of the eight, and to no less than 41b. 3oz. in the highest. The general result was, that the men employed in that work lost from 2 lb. to 5 lb weight twice a-day by perspiration alone. In extreme cases like these, the necessity of a proportionately large supply is self-evident; without it the men would perish in a week. — Editor. KINDS OF NUTRIMENT. 31 nearly as necessary to the articles of diet as the nutrient principle. They should be so managed that one shall be in proportion to the other. Too highly nutritive diet is probably as fatal to the prolongation of life and health, as that which contains an insufficient quantity of nutri- ment. It has been ascertained that carnivorous animals will not live on highly concentrated food alone. Dogs fed on oil or sugar, which are both converted by the digestive organs almost entirely into chyle, are found to become diseased, and die in a few weeks. The inference drawn by Paris,* that it merely " proves that an animal cannot be supported on highly concentrated aliment alone," no doubt, is a correct one ; though opposed to the opinion of Magendie, the author of the experiments, who infers that death proceeds from the want of azote in these articles of diet, and that life cannot be supported on non-azotized aliment.j * Paris on Diet, p. 72. •j- It seems to me that animals die when confined exclusively to the use of concentrated food, not from the want of azote, but sim- ply from such food being out of harmony with their organic struc- ture. The Creator has constituted every animal with relation to its natural or proper food and no other, and if that be denied it, it must of necessity suffer. The cow, for example, has four stomachs specially adapted for digesting herbage, out of which it extracts its nutriment ; but supposing that, by a chemical process, we were able to extract the nutritive essence from the grass or hay, and were to give it in a concentrated state to the cow, can any reason- able being even fancy that the cow would thrive as well as when it had the pleasure of cropping the grass for itself, and employing its own stomachs to effect the preparation ? The thing is absurd, and we may be equally certain, that if the stomach and intestines of any animal are constructed by the Creator for the reception of 32 DIGESTIBILITY OF DIFFERENT The following articles of the materia alimentaria have, in the course of these experiments, been submitted to the action of the stomach and the gastric fluids. I have attempt- ed, in this table, to approximate towards a comparison of the digestibility of the several articles there mentioned. Precision, as to minutes, has not been attended to. When digestion has been accomplished two or three minutes either before or after a certain number of hours and quar- ters, I have set down the quarter to which it approached the nearest. In a subsequent part of this volume, a more particular and minute detail will be found, both of natural and arti- ficial digestion. a mixed and bulky diet, that animal cannot thrive on pure and concentrated food. Magendie evidently overshoots the mark when he seeks for the explanation in the supposed absence of a single chemical principle. — Editor^ KINDS OF ALIMENT. 33 be s-l C o S-l ^ <^ m ■^ o^ Q ^-S ^ c3 TS . e3 fl in C f-, <V O JX rfi " m X t2 CS o O !h c3 5Dg I— I c3 Qj CO CO <" u-i; CO CO Is o o o o ^ o CO CC CO Citl -^ CO ( C3 (M (M (7-5 C-l CI (N CO CC CO CO CO CO <M CO o s-l cq cq Q Mi ^d o 'd j'^ J 58 Friec Boile Broil Boile Cold Roas 02 ce J b. CO J cq 1;^ I o oq • • . . . • • • ce o «v " -1-^ r— 1 . . .-J3 . . . CD &0 • • • n3 • * (U Q o fl Q =il .T > c3 o rr^ . J' 5 • • 6 6 6 6 6 6 ^ ° s^ ^s ,. c3 'Q 'TS 'T3 -a 'd ns (U m'^ QJ >~,^ 'C ».+j .y > f= a> • • • m <; ripe, s ig's fee enison odfish, read a urkey, " == s CQ ^ 02 6 6 6 6^^ 6 6 6 6 6 6 6 Q0Q21 SqqQQQQQ ,, , HPh^OWHO^K o ^ cq 3^ DIGESTIBILITY OF DIFFERENT s i; « o P^ n3 goo P- X .F-« CO ^ ;>. I— I a '^ '^ I—! 1— < -<* CO o ooiooio 0000 CQ CO CO I— ( CO 1—1 CO CO CO CO »«C0»O"^iOC0-*-r(<-^'* 43 ^H^ JH 03 &.03 g o p, o c Sh li >-i • r< 5g Q eq I CIS « I I eg ? i ? ^ ? ? o cq cgooooooo ^000000000 ^"^ ^ . § 4-^ . . •> •" 't^oooooooo O'^ 000000000000 SQQQQQQQaO SQOQQQQPGQQQQ KINDS OF ALIMENT. 35 « tJ o o ^ ■■" "■ ^" i^ ^ o « 03 o pC ■73 pC^* ^^1 0 rG ^ KCOrJ*fO i o -♦J .2 O fcJO O 01 s a o O 03 OQ OS be d ^02 '3 a -4-3 .s 0 i CO 0 i -4-3 03 OD o 0 . -4J -4-> 5C "-g O s 1- o o fcX3 O flj oiSj- 0 c3 0 Sf-C 0 0 0 0 i 1— < '^ •'-1 s s O ■ '3 5 III 03 _03 '^ 2§^ <i^ S S 02 53 " S d P^ 03 S 0 0 S 0 ^ & ' fJ p. a ^ CS © a o QQ 1 'tf '^ d.a 2)^ &. ft a l-H o S p-a o OQ • S CD C3 Ol '1 ft o 'a :^ fcfi O O ^ o o O ^^ .^ .,^ 3 0 0 Y ^13 s «2 |.S -T'^^ • 0 S S H-3 C^ «^ +^ >,>, J3 ^ f- iO 10 ^TSTS , , • • • , . , t— ( , , , . ■^ , 'S CO ^ CO § d 0 •10 iC g ,— , ,-, iO oo o o OO © 0 iO 00 r-H COCQ CO 0-5 coeo CO 00 -* . CQCO (jj--*^ -^ CO CO"^-<*-5i* CO CO iO coco CO CO -<* id CO -^ -!* -^ Tj< ■>* Tt* ^ ^iO ?> ft • 0 ^ 'D , ^ :5 . -<^ -4^ 4^ -fj -4-3 -4J -4.3 -4J -4J « -g CO 03 cc 03 03 KK 03 tn 03 bO • 0 ■^^ a 13 '"^ 5s "^ &^=^ ^4^ ^=2 ^ .5? fH 43 JH^ ^=S ^=^ So** S'3 1 1 G-g o .^ o 0) * \ I ^ 0 s 0 c3 S o > s ^.s i y i s i (D c a. C 0 c 0 s * .« "^ ^H ■-1 t-i •— tn Ld ^1 • i- -i-i (H 'H SU Qcq 3=q QoqQpqq « Q PQQcqG :qQcq ^_ s«" 5tl ^"~ ■ "^ © ^ © t3 ^i" . r^ O ,—1 o ^r^X oasted roiled n o ;-, 0 1 1 { i 0 tw .-g 0 o ^ «C5 a QOW DCffl P^ cq oq PQ c3 -1-3 T2 1— 1 .« pis d ^ rt • • • • » « • » • • • • , • 00^ 03 .r ;-< rC S-iipO 0 s" 03 . . . o • • • • . • • . . • • !=1 S 1^ « 0 ^ e _. ^ 0 S ^■^ 32 0 -*-• S o 6 d d d . . . . t^ • ' !^ ^ "O 5j_ !4-,«« 2; ® 'O'O'^'TS'^ CO «^ 0 0 0 0 cS pC5 0 (U Ji 2 C4-i • • • . . 0 03 pens rj c s o ^666 d d fcJO d d d o 5e o d d 03 d d'fe d 0 d 6 6 6 6 6 ft^.^p- s-S 0 |QQQQQ CO QQ > qPQQQQ 36 DIGESTIBILITY OF DIFFERENT SUBSTANCES. This table is far from being complete. The experi- ments from which it has been formed, were made princi- pally with the view of demonstrating other important principles connected with the subject of digestion. The only way of ensuring minuteness and accuracy as to the comparative digestibility of different kinds of diet, would be to try the effect of the gastric juice, in a series of ex- periments, first on one article of diet, and then on an- other, repeating and adapting them to meet all the va- rious conditions of the stomach, and the vicissitudes and irregularities of the system, until the whole range should be completed — a Herculean task, which it would take years to accomplish. In the above table, the time is counted from the reception of the meal of various arti- cles to the chymification of the v^hole : hence the con- clusions are frequently indefinite, some of the articles being sooner disposed of than others. For instance, if a dinner be eat of venison steak and fat pork, the time of digestion of the whole quantity would, in all probability, be twice as long as if venison had been used alone. Oily substances are digested with great difficulty, and the fat of all meats is converted into oil in the stomach before it is digested. Chymification is most readily effected en solid food, or rather on a soft solid, which is easily divi- sible into shreds or small particles. Such is particularly the character of venison, which is ascertained to be one of the most digestible of substances. The qualities of looseness of texture and susceptibility of division belong to most of those wild meats and game which are gene- VEGETABLES ARE DIGESTED SLOWLY. o/ rally acknowledged to be easy of digestion. Beef and mutton, of a certain age, possess similar qualities. '"' The opinion advanced by Paris, | that the flesh of wild animals is more dense than the domesticated, does not correspond with the experience of those who are well ac- quainted with the former. Although, on making a sec- tion of wild flesh, such appearance may be indicated, yet the fibres are found to be more easily separated by mas- tication, or other force, and are generally tender ; at least, such is the case with the flesh of those animals that are considered luxurious by the epicure. Compare, for ex- ample, the flesh of the wether and the deer, animals which have a near correspondence in their habits, and the difference will be very obvious. The digestibility of most meats is improved by inci- pient putrefaction, sufficient to render the muscular fibre slightly tender. Vegetables are generally slower of digestion than meats and farinaceous substances, though they sometimes pass out of the stomach before them, in an undigested state. Crude vegetables, by some law of the animal economy^ * It is much to be regretted that Dr Beaumont did not make a series of experiments purposely to ascertain the relative diges- tibilities of different kinds of food. From not having attended to any of the precautions requisite to guard against error, the results above narrated can be regarded as only approximative. The ra- pidity of digestion, as the author himself shews, varies greatly ac- cording to the quantity eaten, the amount and nature of the pre- vious exercise, the interval since the preceding meal, the state of health and of the weather, and also the state of the mind. But in scarcely any of the experiments have these conditions been carefully noted Editor. + Paris on Diet, p. 72. 38 INFLUENCE OF MINUTE DIVISION. not well understood, are allowed, even when the stomach is in a healthy state, sometimes to pass the pyloric orifice, while other food is retained there to receive the solvent action of the gastric juice. This may depend upon their comparative indigestibility ; for it is well known that ca- thartic medicines, various fruits, seeds, &c. which operate as laxatives, are not digested ; are incapable of being re- tained in the stomach ; and pass rapidly through the in- testinal tube. When such articles are in excess, they produce considerable derangement, and sometimes fatal consequences. Vegetable, like animal substances, are more capable of digestion in proportion to the minuteness of their di- vision, as I have before remarked, provided they are of a soft solid ; and I cannot, therefore, concur in the opinion expressed by Paris, '^ that potatoes are better when only boiled so as to be rendered tender, and have their shape preserved, than when boiled to a " dry, insipid pow- der." They may be more palatable, and contain more nutriment ; but they are not so easily affected by the gastric solvent. The difference is quite obvious on sub- mitting parcels of this vegetable, in different] states of preparation, to the operation of the gastric juice, either in the stomach or out of it. Boiled, or otherwise cooked to dryness, so as to be easily mashed, potatoes very rea- dily become reduced to a chymous state, when submitted to the action of the gastric juice. When differently pre- pared, and only boiled so as to be rendered barely soft, moist and tenacious, with the shape preserved, entire pieces * Paris on Diet, p. 75. SOLID FOOD DIGESTS QUICKER THAN FLUID. 39 remain long undissolved in the stomach, and very slowly yield to the action of the gastric juice in vials on the bath. Pieces of raw potato, when submitted to the operation of this fluid, in the same manner, almost en- tirely resist its action. Many hours elapse before the slightest appearance of digestion is observable, and this only upon the surface, where the external laminae become a little softened, mucilaginous, and slightly farinaceous. Every physician, who has had much practice in the dis- eases of children, knows that partially boiled potatoes, when not sufficiently masticated (which is always the case wdth children), are frequently a source of colics and bowel complaints, and that large pieces of this vegetable pass the bowels untouched by digestion. These remarks will apply, also, to most other vegetable aliment. The varieties of fish, which are generally used by the citizens of this country, may be regarded as easily sus- ceptible of digestion. The lobster, crab, and some others of the testaceous tribe, are, perhaps, exceptions. Solid food is sooner disposed of by the stomach than fluid, and its nutritive principles are sooner carried into the circulation. It has been observed, however, that the exhaustion from abstinence is quicker removed by liquid than solid aliment. This is undoubtedly true ; and it may be accounted for on the ground of a general sym- pathy existing between the stomach and all the other parts of the body.* It is only necessary, in proof of this * The proper explanation of this fact seems to be the rapid absorption into the system of a part of the liquid aliment, and the 40 DRINKS ESSENTIAL. fact, to appeal to the experience of almost every physi- cian. The violent spasms, contortions, &c. affecting dif- ferent and remote parts of the system, that sometimes supervene on the introduction of crude or indigestible food into the stomach, are pretty clear indications of the powerful sympathy that exists between it and other or- gans or apparatuses. Condiments, particularly those of the spicy kind, are non-essential to the process of digestion, in a healthy state of the system. They afford no nutrition. Though they may assist the action of a debilitated stomach for a time, their continual use never fails to produce an indirect de- bility of that organ. They affect it as alcohol or other sti- mulants do — the present relief afforded is at the expense of future suflPering. Salt and vinegar are exceptions, and are not obnoxious to this charge, when used in moderation. They both assist in digestion — vinegar, by rendering mus- cular fibre more tender — and both together by producing a fluid having some analogy to the gastric juice. Drinks are nearly as essential to the animal system as the more substantial food. Though not subject to diges- tion, they enter into the circulation, and become import- ant agents in the ultimate changes that are undergoing in the tissues of the organism. Simple water is, perhaps, the only fluid that is called for by the wants of the eco- nomy. The artificial drinks are probably all more or less support which it consequently gives almost immediately. Vv^hereas if the whole of the aliment be solid, it must undergo digestion before any of it can be absorbed, and this requires much time. ■ The author himself proves that the absorption of the fluid part of soup begins almost immediately after it is swallowed. — Editor. DRINKS ESSENTIAL. 41 injurious ; some more so than others ; but none can claim exemption from the general charge. Even coffee and tea, the common beverages of all classes of people, have a ten- dency to debilitate the digestive organs. Let any one who is in the habit of drinking either of these articles in a weak decoction, take two or three cups made very strong, and he will soon be aware of their injurious tendency. And this is only an addition to the strength of the narcotic he is in the constant habit of using.* The whole class of alcoholic liquors, whether simply fermented or distilled, may be considered as narcotics^ producing very little diffe- rence in their ultimate effects on the system. The injury which a constant use of wine is known to produce on some stomachs, has been sometimes attributed to the small quantity of tartaric acid which it contains. But it is not the cream of tartar that renders wine so de- leterious to many stomachs. It is the acidity produced by the acetous fermentation of the saccharine matter con- tained in the wine, aided, perhaps, by the alcohol which is in a state of combination with it. Beer has the same effect on the same idiosyncracies, or diseased states of the stomach. Besides, both of these fluids are in a partial stage of acetous fermentation, which is consummated by the increase of temperature in the stomach. * Agreeing with the author on the general opinions expressed in the text, I must diifer from him as to the soundness of the ar- gument founded on strong tea and coffee. His statement merely proves that too much is badx Beef and mutton are in themselves very good, but too much of them is hurtful. Are we therefore to proscribe them ? Weak tea may be good although " very strong''' tea is pernicious. I concur, however, in thinking, that tea, cof- fee, and stimulants are grossly abused. — Editor. D 42 . WHAT IS THE BEST KIND OF DIET. It would be a task of great difficulty to designate the exact kind of diet that would, if generally adopted, be the most conducive to health and longevity. A considerable variety seems to be necessary to man, in a state of civili- zation. This want of variety is induced by long habit, which it would probably be unsafe to break through. Whe- ther man was originally carnivorous or granivorous, is a question which we cannot solve, and perhaps it it not worth the attempt ; at present he is both, and with his present mode of existence we have to do.* The quantity of aliment is probably of more importance than the quality^ to ensure health. The system requires much less than is generally supplied to it. The stomach disposes of a definite quantity. If more be taken than the actual wants of the economy require, the residue remains in the stomach, and becomes a source of irritation, and produces a consequent aberration of function, or passes into the lower bowels in an undigested state, and ex- tends to them its deleterious influence. Dyspepsia is oftener the effect of over-eating and over-drinking than of any other cause. * It would be a mere waste of time to lay down any exact diet for general adoption. Men differ so much from each other, and in their employments, ages, and modes of life, and the same indi- vidual differs so much at different times even from himself, as to render an invariable rule a sheer absurdity..^ — Editor. ( 43 ) CHAPTER III. OF HUNGER AND THIRST. Hunger— Its exciting cause— Different theories of— The Author's theory of hunger— Thirst and its causes— Objections to the Author's theory of hunger. Hunger is a painful sensation, referred to the region of the stomach. It is a kind provision of nature, designed to remind man, and other animated beings, of the neces- sity of replenishing the wastes of the system, as well as contributing to its growth. Much inquiry has been made on this subject, and many theories have been given to account for the phenomenon. It has been supposed by some, that the friction of the internal coats of the empty stomach was the cause of the sensation. This opinion is liable to several objections : — 1st, A healthy stomach di- gests its contents in from one to three or four hours, and hunger is not usually experienced until some time after the latter period. If hunger be the effect of the friction of the p^rietes of the stomach, it ought to be experienced the moment that that organ has disposed of its contents. 2d, In nausea and vomiting, the stomach is brought into a situation, according to this theory, to experience the sensation of hunger ; and yet we know how opposed it is to receiving any thing like food. 3d, In gastritis and fevers the sensation hardly ever occurs, though very lit- 44 EXCITING CAUSE OF HUNGER. tie food shall have occupied the stomach for a long time — perhaps not for weeks. This organ, under such cir- cumstances, is generally empty and irritable, yet the pe- culiar sensation in question hardly ever supervenes. Be- sides, hunger sometimes occurs when the stomach is par- tially or wholly filled. The potation of spirits or brandy and water, and some other indigestible substances of a liquid character, does not remove the sensation, although by this means the parietes of the stomach are as com- pletely separated as by food. It has also been suggested that the sensation of hun- ger is produced by the irritation of a quantity of gastric juice in the stomach, which, by its stimulus, excites the feeling. The principal objection to this doctrine is based upon the fact, that the stomach contains no gastric juice, or, at any rate, but a very small quantity, in its empty state, or when aliment or other irritant is not present. Besides, if it were true that it contained a quantity of the fluid, such fluid does not possess the power of producing any thing like irritation or inflammation of its coats. It is as innoxious to the stomach as the blandest substance in nature. It exerts its influence on free aliment, but not on the living fibre. By referring the sensation to " an energetic state of the gastric nerves, occasioned by an interval of inactivity, during which the vital powers may be supposed to accu- mulate," * it appears to me that we are venturing upon unexplored grounds, of which we know but little. We are not accustomed to call those painful nervous sensa- * Paris on Diet, p. 55. EXCITING CAUSE OF HUNGER. . 45 tions to which the system is sometimes subject, states of high nervous energy. Are they not rather states of ner- vous debility ? or, at any rate, irregular and unhealthy motions ? That the introduction of narcotics into the stomach should destroy the appetite, proves only that they have the same effect oh that organ as they have on other parts of the body ; they paralyse the nerves, and render them incapable of being the media of communication to their common centre. Many other causes have been assigned for this sensa- tion, equally wide, probably of the true one. It has been attributed to the "foresight of the vital principle," a phrase that means any thing, every thing, or nothing, ac- cording to the construction which each one may put upon it. Such explanations conduce nothing to the promotion of science. They are mere sounds and words, which in- geniously convey a tacit acknowledgment of their author's ignorance. Again, the mechanical action of the liver upon the diaphragm, has been accused of producing the sensation of hunger. Some proof, more than mere assertion, is necessary to convince honest inquirers that so remote a cause should produce such effects on the stomach, the immediate seat of the feeling. Of the same nature, is the opinion of the fatigue of the contracted fibres of the stomach, or of compression of the nerves of that organ, &c. &c. Magendie, convinced that all the theories on this sub- ject were unsatisfactory, comes to the following compre- 46 THEORY OF HUNGER. hensive conclusion, that " Hunger is produced like all other internal sensations, by the action of the nervous system, and it has no other seat than in this system it- self, and no other causes than the general laws of organi- zation."* I cannot perceive that such explanations bring the mind to any satisfactory understanding of the sub- ject. In such broad propositions, it is difficult to ascer- tain the exact meaning. If the design is to convey the impression that hunger has no " local habitation ;" that it is an impression, affecting all the nerves of the system inr the same manner ; then the sensation would be as likely to be referred to one organ as another. It is true, that without nervous communication there would be no sensation at all. This applies as well to other parts as to the stomach. The nerves are the media of communica- tion from the sensible parts to the centre of perceptions. They warn the encephalon not only of the injuries, but of the wants of the tissues. We are accustomed to refer local sensations and irritations to the parts apparently affected — desire for urination and defecation, to the blad- der and rectum ; for liquids, to dryness of the mouth and fauces : and we account, in like manner, for other physi- ological and pathological sensations. When we can ar- rive at the exact interpretation of an author, who says that hunger has " no other causes than the general laws of organization," it will then be time to give reasons for an assent to or dissent from the proposition. This subject is, unquestionably, involved in considera- ble doubt and obscurity, and will not, it is to be appre- * Summary of Physiology, p. 1 %^. THE author's theory OF HUNGER. 47 hended, admit of a very speedy elucidation. The Author of Nature is perfect in all His works ; and although we may not understand all the operations of His hands, we are compelled to acknowledge their wisdom, propriety, and beauty. Man would be miserable and wretched in- deed, if he depended solely on his own discretion and judgment to decide upon the quantity and quality of ali- ment necessary to supply the wastes, and administer to the growth, of the system. This paucity of judgment and discretion is, however, more than compensated by an irresistible sensation, which indicates the proper time for the reception of food. The immediate cause of this sen- sation, as we have seen, has not as yet received a very satisfactory explanation, and perhaps will not admit of one. But, although confessedly obscure, we are not denied the privilege of patient investigation, and perse- vering search after truth. Knowledge is progressive, as well in this as every other science ; and every new dis- covery, and every rational hypothesis, are additions to the general stock. Persuaded of the truth of these ge- neral propositions, and anxious mainly to elicit investiga- tion on the subject, I submit the following Theory of Hunger, believing it to be as reasonable, to say the least, as any that has been propagated. My impression is, that the sensation of hunger is pro- duced by a distention of the gastric vessels, or that ap- paratus, whether vascular or glandular, which secretes the gastric juice ; and is believed to be the effect of re- pletion by this fluid. One reason, among others, for this belief, is the estab- 48 THEORY OF HUiNGER. lished fact, that the internal sensations referred to dif- ferent organs, as has been previously alluded to, are caused by some modified action or condition of the parts in the tissues of the organ itself. The modification in the parts to which the sense of hunger is invariably re- ferred, I conceive to be a distention, by the gastric juice, of a particular set of vessels or glands, constituting in part the erectile tissue of the villous coat of the stomach. The sensation varies according to the different degrees or states of distention, fi-om the simplest desire to the most painful sense of hunger ; and is allayed or increased in proportion to the application, or refusal, of alimentary stimulus to the excretory vessels. The greater the dis-_ tention of the vessels, the more acute will be the pain : hence the difference between a short and protracted fast. Appetite and hunger belong to the same class of sensa- tions ; they differ only in degree. In this they are like all other sensations. A little increased circulation in the vessels of the brain produces peculiarly vivid, but not absolutely unpleasant feelings, and gives force and ener- gy to the mental volitions : carried further, it produces most painful sensations. It is unnecessary to cite fur- ther examples. Indeed, it does not need arguments to prove what is the subject of every day's observation. It is well known that the pain from acute inflammation is produced by distention of the blood-vessels. Let any one, who is disposed to try the effect of vascular disten- tion, place a ligature around the finger or arm sufficiently tight to retard the returning blood, and the truth will be sufficiently obvious. THEORY OF HUNGER. 49 It is, therefore, inferred from the pain (and no one, it is believed, will deny that hunger is a painful sensation, whatever may be his opinion of appetite)^ that vessels of some kind are distended ; and it is demonstrated, I think, in some of the following experiments, that these are the gastric vessels. On applying aliment to the internal coat of the stomach, which, in health, is merely lubricated with mucus, innumerable minute papillae, the orifices, undoubtedly, of the gastric vessels, immediately throw out a quantity of the fluid, which mixes with the food. This effect is too sudden, and the secretion too copious, to be accounted for on the ordinary principles and laws of secreting mucous surfaces. The quiescence and re- lief from l3ie unpleasant sensation which are experienced as soon as the vessels are emptied, are, I think, additional proofs of my opinion. It is certain, that at the introduc- tion of every meal, or on the application of alimentary stimulus to the internal coat of the stomach, a very large secretion of a fluid, which has repeatedly been ascertained to be an alimentary solvent, immediately takes place ; and that when the stomach is destitute of food or some other irritating substance, no such secretion can be found in it. And it is more than probable — it, in fact, almost amounts to demonstration, that a large quantity of this fluid must be contained in appropriate vessels, during a fast, ready to obey the call of aliment. I would not be understood to say that the whole quantity necessary for an ordinary meal is eliminated from the blood, previous to the commencement of alimentation ; but that enough E 50 NATURE OF THIRST. is contained in the gastric vessels to produce the sensa- tion of pain or hunger. If it be objected to this theory, that the vessels would become ruptured, or empty themselves into the cavity of the stomach, during a long fast, I reply, that this appa- ratus is probably constituted like many of the other or- gans of the system, and permits the absorption of its se- cretions by the lymphatic or other absorbent vessels. The male semen is constantly being secreted, and depo- sited in its proper seminal vessels, ready to be ejected during the venereal orgasm ; and yet how many men live for years, or perhaps for a whole life, who have no in- tercourse with the other sex. What becomes of the semen under these circumstances ? Taken up, unques- tionably, by the absorbing vessels, as the gastric juice of the stomach is. I offer this theory for consideration, persuaded that the public will allow it such weight as it may have a right to claim : more than this, I have no wish to ask. Thirst. — This sensation is felt in the mouth and fauces. Like hunger, it is a kind provision of Nature, designed to remind men and animals of the necessity, not of replenishing the wasting solids of the system, but of diluting the fluids that are carrying on these processes. Although Magendie has attempted to put a stop to all inquiries on this subject, in the remark, that " Thirst is an internal sensation, an instinctive sentiment ;" " the result of organization, and does not admit of any expla- nation ;" I apprehend a remote cause of this sensation OBJECTIONS TO DR BEAUMONT's THEORY. 51 may be found in the viscidity of the blood, which requires a liquid to render it more fluid, and more susceptible of introduction into the capillaries aud secreting surfaces. The proximate cause may exist in an irritation, a kind of sub -inflammation of the mucous membranes of the mouth and fauces, the effect of the viscid state of the blood, and consequently impervious state of the secretory vessels of these membranes. The sensation of dryness, or thirst, is supposed to be the effect of evaporation, the mouth and throat being constantly exposed to the at- mosphere. When there is sufficient fluidity of the blood, the secretion is so much more copious than the evapora- tion, that a constant moisture is preserved. The sensation of thirst resides in the tissues ; and it is no more " an in- stinctive sentiment" than any other sensation of the eco- nomy. To say that it is the " result of organization," gives no explanation, amounts to nothing, and is certainly, to say the least, a very unsatisfactory way of disposing of the question. Note by the Editor. That the immediate exciting cause of the sensation of hunger is seated in the stomach, there can be no reason to doubt ; but the sensation itself unquestionably takes place in the brain, just as the sensation of hearing does, although in the latter case the exciting cause is an exter- nal impulse acting on the auditory nerves. Accordingly, it has been proved by Brachet that, when the nervous com- munication between the stomach and brain is cut off, the 52 OBJECTIONS TO DR BEAUMONT's THEORY, feeling of hunger instantly ceases, even where a moment before it was ravenously strong. It is important to observe this analogy of relation be- tween different parts performing different functions under one general law, becuase it explains many phenomena, and facilitates inquiry. The cause which excites hearing is a certain condition of the auditory nerve, arising out of its relations to the vibrations of the atmosphere and to the brain. In like manner, the cause which excites the feeling of hunger is a certain condition of the stomachic nerves, arising out of their relation to the state of the gene- ral system, and to the brain. When the system has lost much of its substance, either by severe exercise, or by an unusually long fast, the nerves of the stomach are affected in such a way as to give rise in the brain to the feeling of hunger. When, on the contrary, from a sedentary mode of life, or the shortness of the interval since last meal, there has been little expenditure of substance, the stomachic nerves in harmony with that state convey to the brain the sensation of contentment, and no appetite is felt. Hence the keen appetite of those who live actively and in the open air, and the feeble appetite of sedentary per- sons. The nerves of hearing cannot excite a feeling of sound unless the atmospherical vibrations impinge upon them ; and, in like manner, the stomachic nerves cannot excite a feeling of hunger, unless their activity is stimu- lated by the corresponding state of the system. As, however, it is the brain in which the sensations of both hearing and hunger actually take place, it happens that if it be excited by disease, in that peculiar way which, OBJECTIONS TO DR BEAUMONt's THEORY. 53 in health, follows only the reception of the appropriate external impression made upon the nerve, the same re- sult will ensue as if the external impression were really made, viz. — that sounds will be heard and hunger felt, when neither the ear nor the stomach have undergone any change naturally calculated to produce them. This, accordingly, often happens, and we perhaps experience craving or false hunger quite as often as we hear imaginary sounds. The same relation explains the sudden disap- pearance of appetite on the announcement of agitating news, whether of grief or joy. Dr Beaumont himself attaches no great weight to his theory of the sensation of hunger being caused by the distention of the gastric vessels, and, in truth, it seems not to be borne out by facts. He thinks that the rapidity with which gastric juice is poured out on the introduction of food, is a proof of its previous existence in the gastric vessels ; but when we remember the equal rapidity with which saliva flows into the mouth of a hungry man, when a good roast of meat is placed before him, we shall be disposed to question the fact, — unless, indeed, we hold that the saliva was also stored up in its vessels ready for use. Besides, bad news cannot instantly empty tlie gastric vessels of their contents, and yet they dispel appetite most eiFectually. But having already discussed this subject at some length in another work, I shall not dwell upon it here, farther than to add, that the same prin- ciple applies to the explanation of thirst as of hunger.* • See the Physiology of Digestion, considered with relation to the Principles of Dietetics, 2d edition, p. 18, et seq. { 54 ) CHAPTER IV. ON SATISFACTION AND SATIETY. Quantity of food required — Satiety not a proper guide — The first feeling of satisfaction is the true indication — Gastric juice se- creted in relation to this indication. In the present state of civilized society, with the pro- vocatives of the cuhnary art, and the incentives of high seasoned food, brandy and wines, the temptations to ex- cess in the indulgences of the table are rather too strong to be resisted by poor human nature. It is not less the duty, however, of the watchmen on the walls to warn the city of its danger, however it may regard the premoni- tion. Let them at least clear their own skirts from the stain of unfaithfulness, whatever may be the result. There is no subject of dietetic economy about which people err so much as that which relates to quantity. The medical profession, too, have been accessory to this error, in giving directions to dyspeptics to eat until a sense of satiety is felt. Now, this feeling, so essential to be rightly understood, never supervenes until the invalid has eaten too much, if he have an appetite, which seldom fails him. Those even who are not otherwise, predis- posed to the complaint, frequently induce a diseased state PROPER INDICATION OF ENOUGH EATEN. 55 of the digestive organs by too free indulgence of the ap- petite. Of this fact the medical profession are, gene- rally, not sufficiently aware. Those who lead sedentary lives, and whose circumstances will permit of what is called free living, are peculiarly obnoxious to these com- plaints. But by paying particular attention to their sen- sations during the ingestion of their meals, these com- plaints may be avoided. There appears to be a sense of perfect intelligence conveyed from the stomach to the encephalic centre, which, in health, invariably dictates what quantity of aliment (responding to the sense of hun- ger, and its due satisfaction) is naturally required for the purposes of life ; and which, if noticed and properly at- tended to, would prove the most salutary monitor of health, and effectual preventive of, and restorative from, disease. It is not the sense of satiety^ for this is beyond the point of healthful indulgence, and is Nature's earliest indication of an abuse and overburthen of her powers to replenish the system. It occurs immediately previous to this, and may be known by the pleasurable sensation <di perfect satisfactio7i, ease and quiescence of body and mind. It is when the stomach says enough^ and is dis- tinguished from satiety by the difference of the sensa- tions— the former feeling enough — the latter, too much. The first is produced by the timely reception into the stomach of proper aliment, in exact proportion to the re- quirements of nature, for the perfect digestion of which, a definite quantity of gastric juice is furnished by the pro- per gastric apparatus. But to effect this most agreeable of all sensations and conditions — the real Elysian satisfac- 56 SATIETY A SIGN OP EXCESS. tion of the reasonable epicure — timely attention must be paid to the preliminary processes, such as thorough mas- tication, and moderate or slow deglutition. These are indispensable to the due and natural supply of the sto- mach, at the stated periods of alimentation j for if food be swallowed too fast, *and pass into the stomach imper- fectly masticated, too much is received in a short time, and in too imperfect a state of preparation, to be disposed of by the gastric juice. The quantity of gastric juice either contained in its proper vessels, or in a state of preparation in the circu- lating fluids, is believed to be in exact proportion to the proper quantity of aliment required for the due supply of the system. If a more than ordinary quantity of food be taken, a part of it will be left undissolved in the stomach, and produce the usual unpleasant symptoms of indiges- tion. But if the ingestion of a large quantity be in pro- portion to the calls of nature, which sometimes happens after an unusual abstinence, it is probable that more than the usual supply of gastric juice is furnished ; in which case the apparent excess is in exact ratio to the require- ments of the economy ; and never fails to produce a sense of quiescent gratification, and healthful enjoyment. A great deal depends upon habit, in this respect. Our wes- tern Indians, who frequently undergo long abstinences from food, eat enormous quantities, when they can pro- cure it, with impunity.* * If the principle announced in the above paragraph, that th quantity of gastric juice secreted is always in exact proportion to the proper quantity of aliment required by the system, could be SATIETY A SIGN OF EXCESS. ^ 57 Satiety is produced by tendering too much at once for the wants of the economy ; more than the gastric juice is able to dispose of at the time ; distending the muscular fibres beyond that point so admirably fixed, by the inva- riable and universal laws of the animal system, for agree- able sensations ; disturbing the peculiarly pleasurable, undulatory motions of the rugae of the stomach, in their operations of forming chyme ; and perhaps interrupting, if not diminishing, the secretion of the gastric juice. The redundant aliment, incapable of being dissolved, for want of sufficient gastric juice, remains, and becomes a source of irritation, and renders imperfect the chymification of that which would otherwise have been completed. Hence the sense of weight and disagreeable fulness, attendant on an unusually hearty meal ; the subsequent derange- ment of the digestive functions, and consequent acidities and vitiated contents of the primae vise, from acetic fer- mentation in the stomach, and imperfect formation of chyle in the intestines. clearly demonstrated^ a very important step would be gained in the science of Dietetics. It would not only afford the strongest bar- rier against one of the prevailing sins of the age — eating too much — but would be of incalculable service in the preservation and cure of indigestion, and its gloomy train of consequences. — Editor. ( 58 ) CHAPTER V. MASTICATION, INS ALIVATION, AND DEGLUTITION. Uses of mastication — Nature and use of saliva — Saliva not essen- tial to digestion — Mastication essential as a means of dividing food into minute portions — Deglutition ought to be slow, as the stomach admits only of slow distention. These are the preliminary steps in the process of di- gestion. The comparative importance of these processes has been elevated or depressed, according to the prepon- derance which each of them may have received from the opinions of the different physiologists who have made them subjects of observation. As man and animals are constituted, they are all absolutely necessary to the diges- tion of food. But in an abstract point of view, discon- nected as a means of introducing ingestae into the sto- mach, I believe I hazard nothing in saying that they may be considered as perfectly non-essential to chymification. If the materia alimentaria could be introduced into the stomach in a finely divided state, the operations of mas- tication, insalivation and deglutition, would not be ne- cessary. Aliment is as well digested and assimilated, and allays the sensation of hunger as perfectly, when in- troduced directly into the stomach, in a proper state of division, as when the previous steps have been taken, as may be seen by some of the following experiments. If USES OF SALIVA. 59 particular importance is to be attributed to any of these previous steps, it is certainly due to mastication ; though an undue importance has of late been given to the ac- tion of the saliva. Professor Jackson, of Philadelphia, who has lately published a physiological work on the " Structure and Functions of the Animal Organism," has elevated saliva to a rank in the process of digestion, sel- dom before claimed for it. He considers it the principal solvent, or macerating agent, of alimentary matter. He is sustained in this opinion by Montegre and others. Even Magendie is inclined to favour this belief It is remarked by Paris (On Diet, p. 37), that the in- troduction of saliva into the stomach is " obviously essen- tial to a healthy digestion." That it is generally intro- duced into the stomach with the food is very obvious ; the nature of its action is not so clear. In most of the experiments that follow, artificial digestion was performed without the admixture of saliva. Chyme formed in this way, exhibited the same sensible appearances, and was affected by reagents in the same way, as that which was formed from food which had been previously mas- ticated, mixed with the saliva, and swallowed. It would seem, from two or three of the experiments on artificial digestion, which were instituted for the purpose of com- parison, that the mixture of saliva with the gastric juice rather retarded its solvent action. But I do not wish to deny the utility of the saliva. It is certainly import- ant as a preliminary to digestion. Its legitimate and only use, in my opinion, is to lubricate the food, and to facilitate the passage of the bolus through the or- 60 SALIVA NOT ESSENTIAL TO DIGESTION. gans of deglutition. In this point of view, it is essential. Dry food cannot be swallowed until it receives an admix- ture of a fluid, whether it be saliva or some other liquid, is not, I conceive, a matter of much importance. Any one, disposed to try the experiment, may satisfy himself of this fact, by attempting to swallow a mouthful of dry cracker, meal, or magnesia. He will find it impossible to make the organs of deglutition act till a quantity of fluid is mixed with it. Water will answer the purpose nearly as well as saliva, though the mucous properties of this secre- tion may give it a slight preference. Pathology is not, in my opinion, much indebted to Ruysch, who attributed the loss of appetite to the waste of saliva in a person who was afflicted with a fistula in one of the salivary ducts ; nor to the opinion advanced by others, that the constant spitting of maniacal patients, in- duces loss of appetite. The truth is, that in both cases, the effects are attributed to the wrong causes. There is no difficulty in believing that a foul ulcer in the mouth would be liable to produce nausea and want of appetite ; nor that maniacal patients are generally, if not always, af- fected with diseased organs of digestion. I have known many persons to spit freely and constantly, whose appe- tites and digestion were perfect. Those who smoke to- bacco are constantly discharging large quantities of saliva; and yet I am not aware that dyspepsia is more common with them than with others. I entirely dissent firom the opinion advanced by the author above referred to (Paris), that " insahvation is as essential as mastication." The use of mastication is to MASTICATION ESSENTIAL TO DIGESTION* 61 separate the food into small particles, so that the solvent of the stomach may be applied to a greater extent of surface. There is no mystery about this. Every body knows that the smaller the particles of matter that are submitted to the action of a chemical agent, the more vigorously the agent will act upon them, and the sooner they will be dissolved or decomposed.* Mastication is absolutely necessary to healthy digestion. If aliment, in large masses, be introduced into the stomach, though the gastric juice may act upon its surface, chymifi cation will proceed so slowly, that other changes will be likely to commence in its substance before it will become com- pletely dissolved. Besides, the stomach will not retain undigested masses for a long time, without suffering great disturbance. It is governed by certain laws with respect to aliment. After food has been retained for a certain length of time undigested, say from five to ten hours, according to the healthy or diseased state of that organ, or the quantity received into it, it is either rejected by vomiting, or is permitted to pass into the duodenum and lower bowels, where its presence almost invariably pro- duces colic, flatulence, &c. When, however, the sto- mach is unusually debilitated, food is frequently retained for twenty- four hours or more, and is sometimes the cause of most distressing symptoms, producing, particu- larly in children, convulsions and death. I therefore * In using the word solvent or solution^ in reference to the gas trie juice, I wish to be understood to mean a chemical action, ana- logous to that of the action of mineral acids on the metals ; not like the solution of sugar or salt in water. 62 DEGLUTITION OUGHT TO BE GRADUAL. consider mastication as one of the most important pre- liminary steps in the process of digestion. With respect to deglutition, I shall make but a few remarks. It is important for the preservation of health, that this process should be effected slowly. If food be swallowed rapidly, more will be generally taken into the stomach before the sensation of hunger is allayed, than can be digested with ease. If due attention be paid to the previous step of thorough mastication, we shall not be so likely to err in this latter one. Swallowing very rapidly, produces irregular contrac- tions of the muscular fibres of the oesophagus and stomach ; disturbs the vermicular motions of the rugae ; and inter- rupts the uniform action of the gastric apparatus. The stomach is not designed to receive more food than can be duly mixed with the gastric solvent, already in its proper vessels, or in a state of preparation in the bloodvessels. Perfect harmony of action must exist throughout the whole apparatus, or derangement of healthy action will ensue. The stomach will not admit of the introduction of food, even of a liquid kind, through the aperture, at a rapid rate. If a few spoonfuls of soup, or other liquid diet, be put in with a spoon or funnel, the rugae gently close upon it, and gradually diffuse it through the gastric cavity, entirely excluding more during this action. When a relaxation takes place, another quantity will be received in the same manner. If the valvular portion of the stomach be depressed, and solid food be introduced, either in entire pieces or NOTE BY THE EDITOR. 63 finely divided quantities, the same gentle contraction, or grasping motion, takes place, and continues for fifty or eighty seconds ; and will not allow of the introduction of another quantity until the above time has elapsed ; when the valve may again be depressed, and more food be put in. Food and drinks will be received through the aper- ture no faster, even when the stomach is entirely empty, than they are ordinarily received through the oesophagus. When the subject of these experiments is so placed that the cardia can be seen, and he is allowed to swallow a mouthful of food, the same contraction of the stomach, and closing upon the bolus, is invariably observed to take place at the oesophageal ring. Note hy the Editor. This gradual admission of food into the stomach, seems to be in relation with the gradual supply of gastric juice, necessary for the solution of each portion, and it explains why at a social dinner, where we eat slowly and with short intervals of conversation, we are able to consume a larger quantity and digest it more easily, than when we sit down alone and eat hurriedly and without interruption. In the one case, the stomach has time to adapt its capacity and its gastric secretion to the quantity taken in ; while in the other, it can do neither. ( 64 ) CHAPTER VI. OF DIGESTION BY THE GASTRIC JUICE* Chymification— Agents of. — Spallanzani's theory of Digestion—* Common opinions regarding the gastric juice — Gastric juice has a solvent power — Analysis of— Composition of— -Its^action is purely chemical — Gastric juice described-— Its quantity pro- portioned to wants of the system — Its secretion and action begin on the contact of food-^Evils of frequent eating ex* plained — Gastric juice supplied to all the food at once when the latter is not in excess — Old and new food mix — Effects of exercise on digestion — Bile not essential to chymification— Chyme, its nature and progress — Montegre's theory of diges-. tion — Smith's and Jackson's theories—General remarks. Chymification is effected in the stomach. It is the first stage, proper, of the conversion of aUment into blood ; though in the ordinary course of proceeding, af^ animals are constituted, some previous steps are neces- sary. After the aliment has been received into the stomach, it is subjected to certain evolutions, or motions, propagated by the muscular fibres of that organ ; and is acted upon through the agency of some principle, wliich changes it from a heterogeneous mixture of the various kinds of diet, submitted to its action, to an uniform ho- mogeneous semi-fluid, possessing properties distinct from the elements of which it is composed. The length of time consumed in the operation is various. It depends upon the quantity or quality of the ingestse, the healthy AGENTS OF CHYMIFICATION. 65 or diseased state of the stomach, &c. In the various ex- periments which I have made, the medium time may be calculated at about three and a half hours. It has been suggested by many physiologists, and posi- tively asserted by some, that there is considerable in- crease of the temperature of the stomach during the di- gestion of a meal. But from the result of a great num- ber of experiments and examinations, made with a view of ascertaining the truth of this opinion, in the empty and full state of the organ, and during different stages of chymification, I am convinced that there is no alteration of temperature, unless some other circumstance should produce it. Active exercise always elevates the tempe- rature of the stomach, whether fasting or full, about one and a half degrees. With respect to the agent of chymification, that prin- ciple of life which converts the crude aliment into chyme, and renders it fit for the action of the hepatic and pan- creatic fluids, and final assimilation and conversion into the fluids, and the various tissues of the animal organism — no part of physiology has, perhaps, so much engaged the attention of mankind, and exercised the ingenuity of physiologists. It has been a fruitful source of theoreti- cal speculation, from the Father of Medicine down to the present age. It would be a waste of time to attempt to refute the doctrines of the older writers on this sub- ject. Suffice it to say, that the theories of Concoction, Putrefaction, Trituration, Fermentation, and Macera- tion, have been prostrated in the dust before the lights of science, and the deductions of experiment. It was F 66 SPALLANZANl's THEORY OF CHYMIFICATION. reserved for Spallanzani to overthrow all these unfound- ed hypotheses, and to erect upon their ruins, a theory which will stand the test of scientific examination and experiment. He established a theory of chemical so- lution, and taught that chymification was owing to the solvent action of a fluid, secreted by the stomach, and operating as a true menstruum of alimentary substances. To this fluid he gave the name of Gastric Juice. It does not come within the scope of this work to give a detail of the experiments and reasoning which wrought conviction in the mind of this great man. It is only ne- cessary to say, that it was the result of patient and per- severing experiment and research. The truth of Spallanzani's theory has been sustained, so far as relates to the most important part, the existence of a chemical solvent, by all who have made fair exami- nations and experiments on the subject. The experi- ments of Tiedemann and Gmelin, of Leuret and Las- saigne, confirm the same theory. By far the most respectable and intelligent physiolo- gists have now settled down in the belief that chymifica- tion is effected in the stomach, by a peculiar and specific solvent, secreted in that organ, called, after Spallanzani, the Gastric Juice. From the difficulty, however, of ob- taining and submitting such fluid to the test of experi- ment, and the diversity of results in the examination of such as has been obtained, much indefiniteness is expe- rienced on this subject. The presence of an active sol- vent is rather an admission on their part — a conclusion from the effect to the cause. Broussais, speaking on this OPINIONS ON THE GASTRIC JUICE. 67 subject, says : " It remains for us to know whether the portion of mucous membrane, belonging to the stomach, contains secretory organs, the office of which is to furnish a fluid, fit to produce the assimilation of nutritive sub- stances/' And again, speaking of the gastric juice, " The question is as yet undecided, though, if we are to judge by analogy, we shall observe that many animals are furnished with gastric glands, supplying a digestive liquid." This author admits the presence of a solvent fluid in the stomach, without, however, attempting to ex- plain its specific effects, or mode of operation ; for he says, in another place, " We have expressed our opinion on this subject ; but whether the gastric fluids possess an assimilating property, which, for ourselves, we admit, without pretending to demonstrate its actual presence," &c. Richerand, Bostock, and nearly all the authors of mo- dern date, teach the doctrine of digestion by the gastric juiee, without, however, pretending to explain its exact mode of operation. Professor Dunglison, whose work on " Human Physiology," taken as a whole, is perhaps the most comprehensive, arrives at the same conclusion. He says, " We have too many evidences in favour of the che- mical action of some secretion fi-om the stomach during digestion, to permit us to doubt for a moment of the fact." And again, " From all these facts, then, we are justified in concluding, that the food in the stomach is subjected o the action of a secretion which alters its properties, and is the principal agent of converting it into chyme." I have referred to these learned authors, with the view 68 GASTRIC JUICE HAS A SOLVENT POWER. of shewing the exact state of the science on this sub- ject. Though the theory of chymification by the gastric juice has become almost universal with physiologists, and the medical profession in general, still there are some, even of very modern date, who, with all the lights of science and experiment, from aversion to the slow and tedious processes by which truths are attained, or, per- haps, from the ambition of becoming the discoverers of some new and extraordinary process, or the projectors of some fanciful theory, deny the power of the gastric juice, or even the existence of such a fluid ; and set at naught the experiments, observations, and opinions of the ablest phy- siologists and most experienced writers on this subject. That chymification is effected by the solvent action of the gastric juice, aided by the Tnotions of the stomachy and the natural warmth of the system, not a doubt can remain in die mind of any candid person, who has had an opportunity to observe its effects on alimentary substances, or who has the liberality to credit the opinions of those who have had such opportunities. It has been objected to this hypothesis, that the sensible properties of the gastric juice contradict the opinion of its active solveiit effect. But we should recollect that many things which make very little impression on our external senses, produce most astonishing effects in other situations. The air which we breathe, by which we are surrounded, and which, to our external senses, is almost inappreciable, is one of the most powerful and destructive agents in nature — one portion of which is capable of com- ANALYSIS OF GASTRIC JUICE. 69 bining with all grades of matter, either slowly and imper- ceptibly, as in the gradual decay of all substances, or ra- pidly, as in the combustion of wood, or even the hardest metals, — and which, by means inexplicable to us, sus- tains in life and being the whole of animated nature. The gastric juice has been submitted to chemical ex- amination and analysis, with various results. Perhaps in the present state of the science of chemistry it will not be practicable to ascertain its exact chemical character. The parcels heretofore submitted to analysis have been very impure ; but the result of even these partial exami- nations has been, to shew that this fluid contains a por- tion of free muriatic acid, combined with the acetic and some salts. In the winter of 1832-33, I submitted a quantity of gastric juice, with no other admixture except a small proportion of the mucus of the stomach, to Pro- fessor Dunglison for examination, who, with the assist- ance of the professor of chemistry of the Virginia Uni- versity, effected the following analysis, and was kind enough to communicate the result to me by letter. " University of Virginia, " My Dear Sir, Feb. 6. 1833. " Since I last wrote you, my friend and colleague Pro- fessor Emmett, and myself, have examined the bottle of gastric fluid which I brought with me from Washington, and we have found it to contain free muriatic and acetic acid, phosphates and muriates, with bases ofpotassa, soda, magnesia, and lime, and an animal matter soluble in cold icater, but insoluble in hot. We were satisfied, you recollect, in Washington, that free muriatic acid was pre- 70 ANALYSIS OF GASTRIC JUICE. sent, but I had no conception it existed to the amount met with in our experiments here. We distilled the gas- tric fluid, when the free acid passed over ; the salts and animal matter remaining in the retort. The quantity of chloride of silver thrown down on the addition of the ni- trate of silver, was astonishing." I had been long convinced of the existence of free mu- riatic acid in the gastric fluids. Indeed, it is quite obvi- ous to the sense of taste ; and most chemists agree in this, however they may be at variance with respect to the other constituents. The analysis of Professors Dungli- son and Emmett is certainly as satisfactory as any that has as yet been made. It is a question, too, whether gas- tric juice, in so great a state of purity, has ever before been subjected to chemical analysis. It is to be hoped that no one will be so disingenuous as to attribute to Professor Dunglison the design of find- ing the existence of certain chemical agents in the gas- tric juice, with the view of propping the theory of the chemical action of this fluid, which he has maintained in his work on " Human Physiology ;'' or, in other words, to say that he had determined to find certain results ; and that he had accordingly found them. Those who are ac- quainted with him know that his candour and fairness are above the reach of suspicion, and that he would be equally willing to retract a false opinion as to maintain a correct one. Another quantity was sent to him for further analysis, but I regret that no report has yet been received from him. In April of the present year (1833) a parcel was sub- ANALYSIS OF GASTRIC JUICE. 71 mitted to Benjamin Silliman, M.D., Professor of Chemis- try in Yale College. Professional engagements prevent- ed his examination of the fluid until the 2d of August, when he sent me the following result : — " Examination of the Gastric Fluid, Aug. 2, 1833. "1. The fluid, after being kept in a closely-corked phial more than three months, from April to August, and most of the time in a cellar, remained unaltered, except the formation of a pellicle upon the surface, slightly dis- coloured by red spots. A second pellicle appeared after the precipitation of the first. It was thicker, and more discoloured with dark red spots, like venous blood. " 2. The fluid was cloudy, like a solution of gum ara- ble ; but on filtering it became perfectly clear, and of a slight straw-yellow tinge. " 3. The pellicles, which had the appearance of in- spissated mucus, after being separated from the fluid, be- came, after exposure to the air, throughout of a brownish- red colour, resembling the inner portion of a mass of co- agulated blood. This change seemed to result from a sudden oxygenation. " 4. The fluid exhaled a slight odour^ — not disagree- able— rather aromatic, and very similar to that which it at first exhaled, but not so strong. It was then rather disagreeable. " 5. Taste feebly saline, not disagreeable. " 6. Test papers of litmus, alkanet, and purple cab- bage, were decidedly reddened. Turmeric paper under- went no change ; but, when previously browned by an 72 COMPOSITION OF GASTRIC JUICE. alkali (ammonia), the gastric fluid restored the yellow co- lour. " ?• Nitrate of silver gave a dense white precipitate, which, after standing five minutes in the sun's light, turn- ed to a dark brownish- black, thus indicating muriatic acid. Mur. and nit. barytes gave a slight opalescence, indicat- ing a trace of sulphuric acid ; not improbably there was also some phosphoric acid. " 8. Specific gravity, when taken in a small thin glass tube, containing 201 grs. of distilled water, when filled with the gastric fluid its weight was increased 1 gr. ; weight of the gastric liquor, therefore, 202 grs. The specific gravity is, therefore, about 1.005. But little solid matter in solution." At the instance of Professor Silliman, I committed to the care of Mr Ghan, Consul of his Swedish Majesty in New York, a bottle containing one pint of gastric juice, to be transmitted by him to Professor Berzelius of Stock- holm, one of the most eminent chemists of the age, with a request that he would favour me with an analysis. Some unavoidable delay was experienced in forwarding the bot- tle, and no returns have yet been received. It is hoped, however, that they will arrive in time to be attached in an appendix to this volume. The following results have been obtained from partial examinations and analyses of the gastric juice, or rather, in most instances, of the mixed fluids of the stomach. Spallanzani, in 1793, after many experiments, declared the gastric juice to be entirely neutral, a solvent for all- COMPOSITION OF GASTRIC JUICE. 73 mentary matter within and without the stomach, that it did not -putrefy at the ordinary temperatm'e of the sto- mach, but preserved animal matters from putrefaction, and dissolved them with the aid of heat. Scopoli found in the gastric juice of the rook, water, gelatine, a saponaceous matter, muriate of ammonia, and phosphate of lime. Carminiti, in 1795, found it, in carnivorous animals, salt and bitter, and frequently acid when they had eaten, but not so when fasting.* Viridet, Werner, Hunter, and others, found the gas- tric juice acid. MM. Marquart and Vauquelin found albumen and free phosphoric acid in it. Tiedemann and Gmelin found it to contain, on analysis, muriatic and acetic acid, mucus, very little or no albumen, salivary matter, osmazome,'muriate and sulphate of soda. In the ashes, carbonate, phosphate, and sulphate of lime, and chloride of calcium. Principally from carnivorous animals. Lcuret and Lassaigne, in a hundred parts, found wa- ter ninety-eight, lactic acid, muriate of ammonia, muriate of soda, animal matter soluble in water, mucus, and phos- phate of lime two parts. Montegre (1812), who could vomit at will^\ and who analyzed the fluid so obtained, declared it not to be acid — * Probably because the fluid found in the stomach when fasting was not gastric juice. t See remarks near the close of this section on Montegre's experiments. G 74 GASTRIC JUICE HAS ACTIVE PROPERTIES. not a solvent — not slow to putrefy — and so much like sa^ liva, that he regards it as saliva swallowed. Prout, 1824, declares the gastric juice to be really acid — does not contain an organic acid, but free hydrocliloric or muriatic acid. These opinions are certainly discordant. The majority of evidence, however, is in favour of the existence of pretty active chemical agents in the gastric fluids — per- liaps not sufficient, in comparison with the ordinary ope- rations of chemistry, to account for the digestion or solu- tion of aliment. The discrepance of results in the reports of those who have had opportunities of examining the process of, and have made experiments on, artificial digestion, by the gastric juice, as well as in the chemical examination of this fluid, has been owing more to the difficulty of obtain- ing it pure, in sufficient quantity, and under proper circum- stances, than to any real difference in its effects. Under the circumstances in which the following experiments were made, I flatter myself that these difficulties have been obviated ; and if the inferences are incorrect, the blame must be attached to the experimenter. He can only say, that the experiments were made in good faith, and with a view to elicit facts. I think I am warranted, from the result of all the ex- periments, in saying, that the gastric juice, so far from being " inert as water," as some authors assert, is the most general solvent in nature of alimentary matter — even the hardest bone cannot withstand its action. It is GASTRIC JUICE HAS ACTIVE PROPERTIES. 75 capable, etien out of the stomachy of effecting perfect di- gestion, with the aid of due and uniform degrees of heat (100°. Fahrenheit), and gentle agitation, as will be seen in the following experiments. The fact that alimentary matter is transformed^ in the stomach, into chyme, is now pretty generally conceded. The peculiar process by which the change is effected, has been, by many, considered a problem in physiology. Without pretending to explain the exact inodits operandi, of the gastric fluid, yet I am impelled by the weight of evidence, afforded by the experiments, deductions, and opinions of the ablest physiologists, but more by direct experiment, to conclude that the change eflPected by it on aliment is purely chemical. We must, I think, regard this fluid as a chemical agent, and its operation as a che- mical action. It is certainly every way analogous to it ; and I can see no more objection to accounting for the change effected on the food, on the supposition of a che- mical process, than I do in accounting for the various and diversified modifications of matter, which are operated on in the same way. The decay of the dead body is a che- mical operation, separating it into its elementary prin- (tiples — and why not the solution of aliment in the sto- mach, and its ultimate assimilation into fibrine, gelatine, and albumen ? Matter, in a natural sense, is indestruc- tible. It may be differently combined ; and these com- binations are chemical changes. It is well known that all organic bodies are composed of very few simple prin- ciples, or substances, modified by excess or diminution of some of their constituents. 76 GASTRIC JUICE ACTS CHEMICALLY* The gastric juice appears to be secreted from number- less vessels, distinct and separate from the mucous folli- cles. These vessels, when examined with a microscope, appear in the shape of small lucid points, or very fine papillae, situated in the interstices of the follicles. They discharge their fluid only when solicited to do so, by the presence of aliment, or by mechanical irritation. Pure gastric juice, when taken directly out of the sto- mach of a healthy adult, unmixed with any other fluid, save a portion of the mucus of the stomach, with which it is most commonly, and perhaps always combined, is a clear transparent fluid ; inodorous, a little saltish, and very perceptibly acid. Its taste, when applied to the tongue, is similar to thin mucilaginous water, slightly aci- dulated with muriatic acid. It is readily diffusible in water, wine, or spirits ; slightly effervesces with alkalis ; and is an effectual solvent of the materia alimentaria. It possesses the property of coagulating albumen in an emi- nent degree ; is powerfully antiseptic, checking the putrefaction of meat ; and effectually restorative of healthy action, when applied to old foetid sores, and foul ulcera- ting surfaces. Saliva and mucus are sometimes abundantly mixed w^ith the gastric juice. The mucus may be separated, by filtering the mixture through fine linen or muslin- cambric. The gastric juice, and part of the saliva, will pass through, while the mucus and spumous, or frothy part of the saliva, remains on the filter. When not se- parated by the filter, the mucus gives a ropiness to the. fluid, that does not belong to the gastric juice, and soon APPEARANCE OF GASTRIC JUICE. 77 falls to the bottom, in loose white flocculi. Saliva im- parts to the gastric juice an azure tinge, and frothy ap- pearance ; and, when in large proportion, renders it foetid in a few days ; whereas the pure gastric juice will keep for many months, without becoming foetid. The gastric juice does not begin to accumulate in the ca- vity of the stomach, until alimentary matter be received, and excite its vessels to discharge their contents, for the imme- diate purpose of digestion. It is then seen to exude from its proper vessels, and increases in proportion to the quan- tity of aliment naturally required, and received. A de- finite proportion of aliment, only, can be perfectly digested in a given quantity of the fluid. From experiments on artificial digestion, it appears that the proportion of juice to the ingestae, is greater than is generally supposed. Its action on food is indicative of its chemical character. Like other chemical agents, it decomposes or dissolves, and after combining with a fixed and definite quantity of matter, its action ceases. When the juice becomes sa- turatedy it refuses to dissolve more ; and, if an excess of food have been taken, the residue remains in the stomach, or passes into the bowels in a crude state, and frequently becomes a source of nervous irritation, pain, and disease, for a long time ; or until the vis medicatrix natures, re- stores the vessels of this viscus to their natural and healthy actions — either with or without the aid of medi- cine J^ Such are the appearance and properties of the gastric * This important principle ought never to be lost sight of by the practitioner.— Editor. 78 GASTRIC SECRETION PROPORTIONED TO WANTS. juice ; though it is not always to be obtained pure. It varies with the changing condition of the stomach. These variations, however, depend upon the admixture of other fluids, such as saUva, water, mucus, and some- times bile ; and, perhaps, pancreatic juice. The special solvent itself — the gastric juice — is, probably, invariably the same substance. Derangement of the digestive or- gans, slight febrile excitement^ fright^ or any sudden af- fection of the passions,) causes material alterations in its appearance. Overburthening the stomach, produces aci- dity a,nd rancidity in this organ, and retards the solvent action of the gastric juice. General febrile irritation seems entirely to suspend its secretion into the gastric cavity ; and renders the villous coat dry, red, and irri- table. Under such circumstances, it will not respond to the call of alimentary stimulus.* Fear and anger check its secretion, also ; — the latter causes an influx of bile into the stomach, which impairs its solvent properties. When food is received into the stomach, the gastric vessels are excited by its stimulus to discharge their con- tents, and then chymification commences. It has been a favourite opinion of authors, that food, after it has been received into the stomach, should " remain there a short period before it undergoes any change ;"t the com- mon estimate is one hour. But this is an erroneous conclusion, arising from inaccuracy of observation. Why should it remain there unchanged ? It has been received * Hence the obvious necessity of a scrupulous attention to diet during fever, and other acute diseases. — Editor, -|- Paris on Diet, p. 39. ITS ACTION ON FOOD IS IMMEDIATE. 79 into the organ which is to effect an important change upon it — the gastric juice is ready to commence its work of solution soon after the first mouthful is swallowed ; and, certainly, if we admit that the gastric juice performs the office of a chemical agent, which most physiologists allow, it is contrary to all our notions of chemical action, to allow it one moment to rest. It must commence its operation immediately. That [it does so, is distinctly manifested by close observation of its action on food, in the healthy stomach. But Paris is not alone in this opinion. It appears to have been a favourite doctrine ; and has been regularly handed down from one physiologist to another as a sort of heir'loom to the profession. The successors in the physiological sciences seem to have been compelled to receive it with the legacy of their predecessors, without any doubt of its legitimacy ; when, with a little rational examination of the subject, it would have been found a fair subject of rejection. It will be seen, by the follow- ing experiments, that it has not the slightest foundation in truth ; and to them I refer the reader. It has been said that when one meal follows another in quick succession — or, in other words, when a subsequent meal is taken before the previous one is digested, that it somehow disturbs the process of digestion. This is ge- nerally true ; and it allows of a definite solution. It is because more is received into the storiiach, in the aggre- gate, than the gastric juice can dissolve. And this dis- turbance will result as well when too much food has been taken at once, as when too much has been received in 80 EVILS OF FREQUENT EATING EXPLAINED. rapid succession. But, if the quantity be moderate, no ill effect will ensue. Many children are in the habit of eat- ing as often as once an hour through the day, in small quantities, without experiencing any bad consequences. Cooks are also accustomed to the p^ractice of constantly tasting of the various articles of food which they are pre- paring for the table, and yet I am not aware that they suffer any inconvenience from the habit. From these and other facts, as well as from direct experiment, I think it is perfectly apparent that digestion must progress as well before as after the expiration of an hour. If, as has been suggested, the ingestion of food, in addition to the delay to itself, retards or stops the chymification of that which had been previously received, aliment, as it relates to those children who eat hourly, would be constantly ac- cumulating, and there would remain in the stomach at night the whole quantity taken through the day — a sup- position not to be credited, even by those disposed to make the most of a favourite opinion or doctrine. Doctor Wilson Philip, in his " Treatise on Indiges- tion," says, " the layer of food lying next to the surface of the stomach is first digested, and, in proportion as this undergoes the proper change, and is moved by the mus- cular action of the stomach, that next in turn succeeds, to undergo the same change." That chymification^com- mences on the surface of the food, I have no doubt ; but I apprehend this to be the case as it respects each indi- vidual portion^ and not the whole mass. I have frequent- ly taken out portions from the stomach a few minutes after they had been received into that organ, when they EVILS OF FREQUENT EATING EXPLAINED. 81 appeared to have received a full supply of gastric juice for perfect digestion, when submitted to the artificial mode. When a due and moderate supply of food has been received, it is probable that the whole quantity of gastric juice for its complete solution is secreted, and mixed with it in a short time. When an unusually full meal has been eaten, the necessary quantity for its com- plete solution is not so readily supplied. If a tenacious mass of food be used, the external portion of the whole quantity is first acted on, digested, and succeeding por- tions presented, &c. There is no ground for the opinion inferred, that the gastric juice never leaves the parietes of the stomach, except as it chymifies food. It is a thin fluid, and is governed by the same laws that other thin fluids are. From numerous examinations of the stomach, I feel warranted in saying, at least in the human subject, that there is a perfect admixture of gastric juice and food — that the particles of food are constantly changing their relations with each other, and that they are mixed with a quantity of fluid, the gastric juice, liquids that have been taken during the meal, and (as there has generally been observed a large proportion of fluid, even after a dry and solid meal) I have been led to suspect a synthe- tic formation of water from its elements. This mixture is perfectly heterogeneous at first, and is kept in constant agitation by the churning motions of the stomach. If the contents of the stomach be taken out in from thirty minutes to an hour after eating, they will be found to be composed of perfectly formed chyme and particles of food, intimately mixed and blended ; sometimes in larger and 82 GASTRIC JUICE APPLIED TO ALL THE FOOD AT ONCE. sometimes in smaller proportions, according to the vigor- ous or enfeebled state of the digestive organs, or the quantity or quality of aliment taken. Most commonly, if the meal have been moderate, the process of digestion will continue in the portion taken out, when it is placed on the bath at a proper temperature, and the motions of the stomach are imitated. From the circumstance, that the introduction of sponge, tubes, pebbles, &c., by Spallanzani and others excited the discharge of the gastric juice, and from the fact that the gum-elastic tube, in my experiments, produced the same effect when the stomach was empty and healthy, I infer that the first effect of aliment on the stomach is one of irritation of the gastric papillae, thus exciting the dis- charge of the gastric juice, and stimulating the muscular fibres of the stomach. The vermicular motions, being excited by mechanical irritation, not only carry the in- gestae into all parts of the stomach, and diffuse its me- chanical influence throughout the whole inner surface of this organ ; but, by this means, they uniformly mix the aliment with the gastric juice, which is constantly being secreted in proportion to the quantity of food received into the stomach (unless that be too much for the wants of the economy) until chymification be completed. Some stimulus seems to be necessary to continue the motions of the stomach after chymification is accomplished, in order to effect its complete discharge into the lower bowels. And it appears highly probable that the com- pound fluid of gastric juice and aliment, or chyme, by its acquired acid properties, affords this stimulus, and pro- OLD AND NEW FOOD MIX. 83 pagates the contractile motions of this organ, even after the mechanical irritation of the crude food ceases. This fluid acquires new chemical properties, becomes more acid and stimulating, as chymification advances, until it is completed. When it is all transferred to the duodenum, the motions of the stomach cease. From a number of experiments on rabbits by Doctor Wilson Philip* with the view of ascertaining the process of digestion, this gentleman has brought his mind to the conclusion, that when food has been taken at diiferent times, " the new is never mixed with the old food." With every feeling of respect for so valuable and indefatigable a contributor to physiological science, I must beg leave, however, to dissent from this opinion. In many of his experiments the rabbits were killed soon after the intro- duction of a fresh quantity of food, and, generally, of a very different kind. The result was, that it was found separate from the old food, which was in an advanced stage of digestion. It was in the centre of the old food, and surrounded by it. This is precisely where a new bolus would be received, and retain its shape and con- sistence, in some measure, until disturbed and broken up by the motions of the stomach. By allowing sufficient time for the action of this organ, it is probable that the line of separation would not have been perceived. In- deed, the Doctor concedes that, when the second quan- tity of food was of the same kind as the first, and the rab- bit had been left to live for some time, the line of sepa- ration was very indistinct. It appears that he fed rab- * On Digestion. 84 NEW AND OLD FOODS MIX. bits on oats^ and, after making them fast for sixteen or seventeen hours, he fed them on as much cabbage as they chose to eat, " and killed them at different periods, from one to eight hours after they had eaten it ;" when the line of separation between the new food and that which had been eaten from eighteen to twenty-Jive hours before was no doubt quite distinct. I confess I know very little about the habits of these animals as it respects their modes of digestion ; but I should be inclined to think that, if the " line of separation" between the two portions of food were not sufficiently distinct, it was not for want oitime. In man, one-fifth of the time would have been more than sufficient to have disposed of any reasonable quantity of food. Comparative physiology, as well as comparative ana- tomy, is undoubtedly very useful ; but, at the same time, it will not do to make it of general application. The rab- bit is a ruminating animal ; and is it not probable that the " new food" found in the " small curvature," if it be in fact retained there, is detained for the purpose of re- gurgitation and remastication before it is digested ? If the circumstance be true, and there be no deception in the case, I think this snust be the design of the con- trivance. Arguments from analogy may be very plausible, and are certainly very allowable when the subject presents no other mode, but they are not conclusive. We cannot judge of the mode of digestion in the human stomach by that of animals, particularly the granivorous and rumina- ting animals. Carnivorous animals most resemble man EFFECT OF EXERCISE ON DIGESTION. 85 in their digestive apparatus. One thing is certain, and it is capable of demonstration in the stomach of the sub- ject of these experiments, that old and new food, if they are in the same state of comminution, are readily and speedily mixed in the stomach. On the subject of exercise or repose, during the diges- tion of a meal, there has been some diversity of opinion. It has generally been conceded, however, that a state of repose is most favourable to chymification. It has been said that during the digestion of aliment, the energies of the system were centred on the stomach, and should not be withdrawn to any distant part ; that the stomach be- comes a " centre of fluxion," &c. &c. I protest, again, against the use of terms which have no definite meaning. I believe the benefits of science will be better subserved by adhering to facts, and the deductions of experiment, than by the propagation of hypotheses founded on un- certain data. From numerous trials, 1 am persuaded that moderate exercise conduces considerably to healthy and rapid digestion.* The discovery was the result of accident, and contrary to preconceived opinions. I ac- count for it in the following way. Gentle exercise in- * Perhaps the Author's proposition is expressed in too general terms. After a moderate meal, such as we are accustomed to take at luncheon, moderate exercise seems to promote digestion. But that active exercise immediately after z.full meal, such as is gene- rally taken for dinner, is prejudicial to its digestion, seems to me to be proved by daily and unequivocal experience, and I have often seen patients labouring under indigestion benefited by refraining from it. During the later stages of digestion, how- ever, beginning an hour or two after eating, moderate exercise is unquestionably conducive to its completion. — Editor. 86 EFFECTS OF EXERCISE ON DIGESTION. creases the circulation of the system, and the temperature of the stomach. This increase of temperature is gene- rally about one and a half degrees. Now, if the gastric juice be a solvent, its action is similar to other chemical solvents, and its rapidity is increased in proportion to the elevation of temperature. Of the reason, I leave others to judge ; the effect is certain. Severe and fatiguing exercise, on the contrary, retards digestion. Two rea- sons present themselves for this, — the debility which fol- lows hard labour, of which the stomach partakes ; and the depressed temperature of the system, conseauent upon perspiration and evaporation from the surface. Exercise, sufficient to produce moderate perspiration, increases the secretions from the gastric cavity, and pro- duces an accumulation of a limpid fluid within the sto- mach, slightly acid, and possessing the solvent properties of the gastric juice in an inferior degree. This is pro- bably a mixed fluid, a small proportion of which is gastric juice.* Bile is not essential to chymification. It is seldom found in the stomach except under peculiar circum- stances. I have observed that when the use of fat or oily food has been persevered in for some time, tliere is generally the presence of bile in the gastric fluids. * I have often witnessed the effect of exercise attended with moderate perspiration in improving both the appetite and diges- tion, and am therefore in the habit of'recommending it to be car- ried to that extent by dyspeptic patients. In relieving the ten- dency to acidity, its good effects are equally apparent. The observations in the text afford a good physiological explanation of the fact, — Editor. BILE NOT ESSENTIAL TO CHYMIFICATION. 87 Whether this be a pathological phenomenon, induced by the peculiarly indigestible nature of oily food, or whether it be a provision of nature to assist the chymification of this particular kind of diet, I have not as yet satisfied myself. Oil is affected by the gastric juice with consi- derable difficulty. The alkaline properties of the bile may render it more susceptible of solution in this fluid, by altering its chemical character. Irritation of the py- loric extremity of the stomach with the end of the elastic tube, or the bulb of the thermometer, generally occasions a flow of bile into this organ. External agitation, by kneading with the hand on the right side, over the re- gions of the liver and pylorus, produces the same effect. It may be laid down as a general rule, however, subject to the exceptions above mentioned, that bile is not ne- cessary to the chymification of food in the stomach. Magendie «ays, " I believe that, in certain morbid con- ditions, the bile is not introduced into this organ " (the stomach) ; inferring, that in a healthy state it is always to be found there. There can hardly be a greater mis- take. With the exceptions that I have mentioned, it is never found in the gastric cavity in a state of health ; and it is only in " certain morbid conditions" that it is found there.* * There is one form of impaired digestion in which the fat of bacon is digested with perfect ease, where many other apparently more appropriate articles of food oppress the stomach for hours. It would be interesting and useful to ascertain, whether, in these cases, bile is present in the stomach, and also to discover in- dications by which we could predicate whether bacon will be suitable. As yet, although I have often seen the fact of bacon being easily digested by a weak stomach, I have not been able to 88 CHYME, ITS NATURE AND PROGRESS. When bile is found with the gastric juice, the acid taste is diminished, and the flavour of the bile prevails in proportion to the quantity in the mixture. The resulting compound of digestion in the stomach, or chyme, has been described as " a homogeneous, pulta- ceous, greyish substance, of a sweetish insipid taste, slightly acid," &c. In its homogeneous appearance, it is invariable ; but not in its colour ; that partakes very slightly of the colour of the food eaten. It is always of a lightish or 'greyish colour, varying in its shades and appearance, from that of cream, to a greyish or dark- coloured gruel. It is, also, more consistent at one time than at another ; modified, in this respect, by the kind of diet used. This circumstance, however, does not affect its homogeneous character. A rich and consistent quantity is all alike, and of the same quality. A poorer and thinner portion is equally uniform in its appearance. Chyme from butter, fat meats, oil, &c., resembles rich cream. That from farinaceous and vegetable diet, has more the appearance of gruel. It is invariably distinctly acid. The passage of chyme from the stomach is gradual. Portions of chyme, as they become formed, pass out, and are succeeded by other portions. In the early stages, the passage of the chyme into the duodenum is more slowly effected than in the later stages. At first, it is more mixed with the undigested portions of aliment, and distinguish by the symptoms, prior to experience, the cases in which it ought to be allowed. In many cases, it proves extremely indigestible. Possibly this may have some relation to the pre- s>ence or absence of bile— Editor. MONTEGRE^S THEORY OF DIGESTION. 89 is probably separated with considerable difficulty by the powers of the stomach. In the later stages, as the whole mass becomes more and more chymified and fitted for the translation, the process is more rapid ; and is accelerated by a peculiar contraction of the stomach, a description of which will be found in the next section. It appears to be a provision of nature, that the chyme, towards the latter stages of its formation, should become more stimulating, and operate on the pyloric extremity of the stomach, so as to produce this peculiar contraction. After the expulsion of the last particles of chyme, the stomach becomes quiescent and no more juice is secreted until a fi'esh supply of food is presented for its action, or some other mechanical irritation is applied to its internal coat. Water and alcohol are not affected by the gastric juice. Fluids of all kinds are subject to the same exemption, unless they hold in solution or suspension some animal or vegetable aliment. Fluids pass from the stomach very soon after they are received, either by absorption or through the pylorus. Since the general adoption of the theory of a specific solvent fluid, others have been proposed. M. Montegre, who, it is said, had the power of vomit- ing at pleasure, performed a series of experiments on the fluids of the stomach obtained in this way, which in- duced him to come to a different conclusion on the sub- ject of digestion. " He conceives that what has been supposed to be the gastric juice, is in fact nothing but H 90 DRS SMITH AND JACKSON's THEORIES. saliva ; that it possesses no peculiar powers of acting on alimentary matter ; that the principal use of the gastric juice is to dilute the food ; and that the only action of the stomach consists in * une absorption vitale et elective/ in which the absorbent vessels, in consequence of their peculiar sensibility, take up certain parts of the food and reject others."* A complete refutation of the conclusions drawn from the experiments of Montegre will be found in the fact, which has been tested by more than tvro hundred exa- minations and experiments made by me on the gastric cavity, that there never exists free gastric juice in the stomach unless excited by aliment or other stimulants. The fluid obtained by Montegre was, in all probability, a mixture of saliva (which had been unconsciously swal- lowed) and the mucus of the stomach. Neither of these secretions are capable of digesting aliment, nor could the peculiar products, generally obtained from the chemi- cal analysis of the gastric juice, be found in them. The hypotheses proposed by Professors Smith and Jackson of this country, are modifications of Montegre's theory. The former of these gentlemen supposes that digestion is performed "by the veins of the stomach and by the liver." He contends, " that the first step in the process of digestion is effected by the capillary veins originating in the villi of the stomach, with absorbing extremities, and terminating in the great branches of the vena portae ;"| * Note in Bostock's Physiology, vol. ii. p. 384. •^ Essay on Digestion, p. 63. DBS SMITH AND JACKSON's THEORIES. 91 that this action is continued through the small intestines ; that the absorbing veins take up the nutrient principles of the food, and reject, as excrementitious, the innutri- tions part ; that these nutrient principles are mixed with the returning blood within the cavity of the abdomen, and are carried into the liver, where the final processes of animalization and conversion into blood are completed. Professor Jackson, in a recent work, has proposed a new theory, or rather revived, in some measure, the the- ory of maceration. His hypothesis, as nearly as can be collected from his work, is as follows : — He supposes that digestion is performed by submitting food to the action of diflPerent fluids, each of which has " solvent powers for different principles ;"* that the nutrient principles exist already formed in food, and are released from principles that are not required for nutrition, by a species of solu- tion, or maceration. The diflPerent fluids, as saliva, mu- cus from the mouth, throat, stomach, intestines, the bile and pancreatic juice, are the solvents of the diflPerent in- nutritive principles, and separate them from nutriment. He attributes great importance to the action of the sa- liva ; thinks it exercises a " very energetic operation on the food," &c., and denies, altogether, the existence of a specific solvent fluid. It is unfortunate for the interests of physiological science, that it generally falls to the lot of men of vivid imaginations, and great powers of mind, to become res- tive under the restraints of a tedious and routine mode * Principles of Medicine, founded on the Structure and Func- tions of the Animal Organism, p. 354. 92 DRS SMITH AND JACKSON's THEORIES. of thinking, and to strikeout into bold and original hy- potheses to elucidate the operations of nature, or to ac- count for the phenomena that are constantly submitted to their inspection. The process of developing truth by patient and persevering investigation, experiment, and research, is incompatible with their notions of unrestrain- ed genius. The drudgery of science they leave to hum- bler and more unpretending contributors. The flight of genius is, however, frequently erratic. The bold and original opinions of Brown for a long time unsettled the practice of medicine ; and the later opinions of Montegre and others, have had a like effect on the sister science of physiology. It iS) however, a right, which men of genius possess, in common with others, to propose hypotheses, and to support them with such arguments and deductions as they may have in their power to bring. Great cau- tion and circumspection ought, however, to be observed.^ It is dangerous to unsettle long established truths ; for it is difficult to limit the extent of error. The gratifica- tion of a morbid desire to be distinguished as the propa- gator of new principles in philosophy, or as the head of a new sect, is not the only result to be expected from such heresies. New opinions or doctrines, whether true or false, will have admirers and followers, and will lead to practical results. And the errors of one man may lead thousands into the same vortex. These, of course, are designed as general remarks ; and I have no wish to apply them, so far as bad motives are inferred, to the highly respectable gentlemen men- tioned above. Honest objections, no doubt, are enter- DRS SMITH AND JACKSON's THEORIES. 9^ tained against the doctrine of digestion by the gastric juice. That they are so entertained by these gentlemen, I have no doubt. And I cheerfully concede to them the merit of great ingenuity, talents, and learning, in raising objections to the commonly received hypothesis, and ability in maintaining their peculiar opinions. But we ought not to allow ourselves to be seduced by the inge- nuity of argument or the blandishments of style. Truth, like beauty, when " unadorned, is adorned the most ;" and in prosecuting these experiments and inquiries, I be- lieve I have been guided by its light. Facts are more persuasive than arguments, however ingeniously made, and by their eloquence, I hope I have been able to plead for the support and maintenance of those doctrines, which have had for their advocates such men as Sydenham, Hunter, Spallanzani, Richerand, Abernethy, Broussais, Philip, Paris, Bostock, the Heidelberg and Paris Pro- fessors, Dunglison, and a host of other luminaries in the science of physiology. ( 94 ) CHAPTER VII. OF THE APPEARANCE OF THE VILLOUS COAT, AND OF THE MOTIONS OF THE STOMACH. Appearance of the villous coat— Gastric Papillae — Healthy aspect of the villous coat — Its aspect in disease — Motions in the sto- mach— Effects of — Order of contraction in the muscular fibres of the stomach — Passage of the chyme out of the stomach. The inner coat of the stomach, in its natural and healthy state, is of a light, or pale pink colour, varying in its hues, according to its full or empty state. It is of a soft or velvet-like appearance, and is constantly co- vered with a very thin, transparent, viscid mucus, lining the whole interior of the organ. Immediately beneath the mucous coat, and apparently incorporated with the villous membrane, appear small, spheroidal, or oval shaped, glandular bodies, from which the mucous fluid appears to be secreted. By applying aliment, or other irritants, to the internal coat of the stomach, and observing the effect through a magnifying glass, innumerable minute lucid points, and very fine nervous or vascular papillae, can be seen arising from the villous membrane, and protruding through the mucous coat, from which distils a pure, limpid, colour- less, slightly viscid fluid. This Jiuid, thus excited, is in- GASTRIC PAPILLA AND THEIR SECRETIONS. 95 variably distinctly acid. The mucus of the stomach is less fluid, more viscid or albuminous, semi-opaque, some- times a little saltish, and does not possess the slightest character of acidity. On applying the tongue to the mu- cous coat of the stomach, in its empty, unirritated state, no acid taste can be perceived. When food, or other irritants have been applied to the villous membrane, and the gastric papillae excited, the acid taste is immediately perceptible. These papillae, I am convinced fi'om ob- servation, form a part of what are called by authors, the villi of the stomach. Other vessels, perhaps absorbing as well as secretory, compose the remainder. That some portion of the villi forms the excretory ducts of the ves- sels, or glands, I have not the least doubt, from innume- rable ocular examinations of the process of secretion of gastric juice. The invariable effect of applying aliment to the internal, but exposed part of the gastric membrane, when in a healthy condition, has been the exudation of the solvent fluid, from the above-mentioned papillae. — Though the apertures of these vessels could not be seen, even with the assistance of the best microscopes that could be obtained, yet the points from which the fluid issued were clearly indicated by the gradual appearance of innumerable very fine lucid specks, rising through the transparent mucous coat, and seeming to burst, and dis- charge themselves upon the very points of the papillae, diffusing a limpid, thin fluid over the whole interior gas- tric surface. This appearance is conspicuous only during alimentation or chymifi cation. These lucid points, I have no doubt, are the termination of the excretory ducts 96 GASTRIC PAPILLAE AND THEIR SECRETIONS. of the gastric vessels or glands, though the closest and most accurate observation may never be able to discern their distinct apertures. The fluid so discharged, is absorbed by the aliment in contact, or collects in small drops and trickles down the sides of the stomach to the more depending parts, and there mingles with the food or whatever else may be contained in the gastric cavity. This fluid, the efficient cause of digestion — the true gastric juice of Spallanzani, I have no doubt— has generally been obtained, for expe- riment, by mechanical irritation of the internal coat of the stomach, produced by the introduction of a gum- elastic tube, through which it has been procured. The gastric juice never appears to be accumulated in the cavity of the stomach while fasting ; and is seldom, if ever, discharged from its proper secerning vessels, except when excited by the natural stimulus of aliment, mecha- nical irritation of tubes, or other excitants. When ali- ment is received, the juice is given out in exact proportion to its requirements for solution, except when more food has been taken than is necessary for the wants of the system. When mechanical irritation by a non-digestible sub- stance, as the elastic tube, stem of the thermometer, &c., has been used, the secretion is probably less than when the irritation has been produced by such substances as are readily dissolved in the gastric juice. Alimentary stimulus, when taken into the stomach, is diffused over the whole villous surface, and excites the gastric vessels generally to excrete their fluids copiously ; whereas the irritation of tubes, &c., is local, and produces only a par- BEA^LTflY ASPECT OP THE VILLOUS COAT. 97 tial excitement of the vessels, and a scanty flow of the gastric juice. Hence the slowness in obtaining the clear fluid from the empty stomach through the tube. I have never, on numerous trials, been able to obtain at any one time more than one and a half or two ounces of this fluid after the stomach had disposed of its alimentary matters, however long the period of abstinence had been. The discharge of this small quantity has generally been ex- cited by the introduction of the tube. Ten, fifteen, or more minutes, were necessary to collect even this small quantity. Whenever fluid was obtained in larger quan- tity, as was sometimes the case, it invariably contained more than the usual quantity of mucus. On viewing the interior of the stomach, the peculiar formation of the inner coats is distinctly exhibited. When empty, the rugae appear irregularly Tolded upon each other, almost in a quiescent state, of a pale pink colour, with the surface merely lubricated with mucus. On the application of aliment^ the action of the vessels is increased, the colour brightened, and the vermicular mO' tions excited. The small gastric papillae begin to dis* charge a clear transparent fluid (the alimentary solvent), which continues abundantly to aocumulate as aliment is r-eceived for digestion. If the mucous covering of the villous coat be wiped off with a sponge or handkerchief during the period of chy- mification, the membrane appears roughish, of a deep pink colour at first ; but in a few seconds, the follicles and fine papillae begin to pour out their respective fluids, which being diffused over the parts abraded of mucus, 98 ITS APPEARANCE IN DISEASE. restore to them their peculiar soft and velvet-like appear- ance, and pale pink colour, corresponding with the undis- turbed portions of the membrane, and the gastric juice goes on accumulating, and trickles down the sides of the stomach again. If the membrane be wiped off when the stomach is emptjj or during the period of fasting, a similar rough- ness and deepened colour appear, though in a less de- gree, and the mucous exudation is more slowly restored. The follicles appear to swell more gradually. The fluids do not accumulate in quantity sufficient to trickle down^ as during the time of chymification. The mucous coat only appears to be restored. The foregoing, I believe to be the natural appearances of the internal coat of the stomach in a healthy condition of the system. In disease, or partial derangement of the healthy func- tion, this membrane presents various and essentially dif- ferent appearances. In febrile diathesis, or predisposition, from whatever cause— obstructed perspiration, undue excitement by stimulating liquors, overloading the stomach with food — fear, anger, or whatever depresses or disturbs the nervous system — the villous coat becomes sometimes red and dry, at other times, pale and moist, and loses its smooth and healthy appearance ; the secretions become vitiated, greatly diminished, or entirely suppressed ; the mucous coat scarcely perceptible ; the follicles flat and flaccid, with secretions insufficient to protect the vascular and liervous papillae from irritation. ASPECT OF VILLOUS COAT IN DISEASE. 99 There are sometimes found, on the internal coat of the stomach, eruptions or deep red pimples, not numerous, but distributed here and there upon the villous mem- brane, rising above the surface of the mucous coat. These are at first sharp-pointed and red, but frequently become filled with white purulent matter. At other times, irre- gular, circumscribed red patches, varying in size or ex- tent from half an inch to an inch and a half in circum- ference, are found on the internal coat. These appear to be the effect of congestion in the minute bloodvessels of the stomach. There are, also, seen at times small aphthous crusts in connection with these red patches. Abrasion of the lining membrane, like the rolling up of the mucous coat into small shreds or strings, leaving the papillae bare for an indefinite space, is not an uncommon appearance. These diseased appearances, when very slight, do not always affect essentially the gastric apparatus. When considerable, and particularly when there are correspond- ing symptoms of disease, as dryness of the mouth, thirst, accelerated pulse, &c., no gastric juice can he extracted, not even on the application of alimentary stimulus. Drinks received are immediately absorbed, or otherwise disposed of, none remaining in the stomach ten minutes after being swallowed. Food taken in this condition of the stomach, remains undigested for twenty-four or forty- eight hours or more, increasing the derangement of the whole alimentary canal, and aggi'avating the general symptoms of disease.* * These appearances of the villous coat and the non-secretion 100 Motions of the stomach. After excessive eating or drinking, chymificatioH ig retarded ; and, although the appetite be not always im- paired at first, the fluids become acrid and sharp, exco- riating the edges of the aperture, and almost invariably produce aphthous patches, and the other indications of a diseased state of the internal membrane, mentioned above. Vitiated bile is also found in the stomach under these circumstances ; and floccvdi of mucus are much more abundant than in health. Whenever this morbid condition of the stomach occurs^ with the usual accompanying symptoms of disease, there is generally a corresponding appearance of the tongue. When a healthy state of the stomach is restored, the tongue invariably becomes clean. Motions of the Stomach. — With the anatomy of this organ, I have at present nothing to do ; it does not come within the limits which I have prescribed to myself. Its motions, as comprising a part of the process of diges- tion, I have endeavoured to observe as accurately as practicable, and I give the result. The human stomach is furnished with muscular fasci- culi, so arranged as to shorten its diameter in every direc- tion. By the alternate contraction and relaxation of these bands, a great variety of motion is induced on this of the gastric juice in feverish states of the system, are very im- portant in a practical point of view, and shew how injurious, and contrary to nature it is to insist on giving food in such circum- stances by way of supporting the strength. Drinks are useful, be- cause they are not digested but absorbed, and thus refresh the body ; but solid food taken into the stomach, can act only as an irritant where there is no gastric juice to digest it. — Editor. MOTIONS OF THE STOMACH. 101 organ, sometimes transversely and at other times longi- tudinally. These alternate contractions and relaxations, when affecting the transverse diameter, produce what are called vermicular or peristaltic motions. The effect of the contraction of the longitudinal fibres, is to approxi- mate the splenic and pyloric extremities. When they all act together, the effect is to lessen the cavity of the stomach, and to press upon the contained aliment, if there be any in the stomach. These motions not only produce a constant disturbance, or churning of the con- tents of this organ, but they compel them, at the same time, to revolve around the interior from point to point, and from one extremity to another. In addition to these motions, there is a constant agitation of the stomach, produced by the respiratory muscles. These contractions and relaxations of the nmscular fasciculi do not observe any very exact mode. Their motions are modified by various circumstances, such as the stimulant or non-stimulant property of the ingestae, the healthy or unhealthy state of the internal coat of the stomach, by exercise, and by repose, &c. &c. The ordinary course and direction of the revolutions of the food, are first, after passing the oesophageal ring, from right to left, along the small arch ; thence, through the large curvature, from left to right. The bolus, as it enters the cardia, turns to the left, passes the aperture, descends into the splenic extremity, and follows the great curvature towards the pyloric end. It then returns, in the course of the smaller curvature, makes its appearance 102 MOTIONS OF THE STOMACH. again at the aperture in its descent into the great curva- ture, to perform similar revolutions. Such I have ascertained to be the revolutions of the contents of the stomach, from being able to identify par- ticular portions of food, and from the fact, that the bulb of the thermometer, which has been frequently intro- duced during chymification, invariably indicates the same movements. These revolutions are completed in from one to three minutes. They are probably induced, in a great measure, by the circular or transverse muscles of the stomach, as indicated by the spiral motion of the stem of the thermometer, both in descending to the pyloric portion and ascending to the splenic* These motions are slower at first than after chymification has conside- rably advanced. While these revolutions of the contents of the stomach are progressing, the trituration or agitation is also going on. There is a perfect admixture of the whole ingestae, during the period of alimentation and chymification. There is nothing of the distinct lines of separation be- tween old and new food, and peculiar central or periphe- ral situation of crude, as distinguished from chymified aliment, said to have been observed by Philip, Magendie and others, in their experiments on dogs and rabbits, to be seen in the human stomach; at least in that of. the subject of these experiments. The whole contents of the stomach, until chymification be nearly complete, ex- * The terms " descending " and " ascending," are used here, as well as in many other places, relatively, because the examina- tions were generally made while the man was lying on his right side« EFFECT OF STOMACHIC CONTRACTIONS. 103 hibit a heterogeneous mass of solids and fluids ; hard and soft ; coarse and fine ; crude and chymified ; all inti- mately mixed, and circulating promiscuously through the gastric cavity, like the mixed contents of a closed vessel, gently agitated or turned in the hand. If a mouthful of some tenacious food be swallowed, after digestion is considerably advanced, it will be seen passing the opening, to the great curvature ; and in the course of about one and a half or two minutes, it will re- appear, with the general circulating contents, more or less broken to pieces, or divided into smaller pieces ; and very soon loses its identity. This agitating motion has the eflPect, and is undoubtedly designed, to break up the bolus, as well as to separate the external and chymified portion of the particles of food, and allow the undigested portions to come in contact with the gastric juice, their proper solvent. If the motions were simply revolution- ary, the central portions would retain their situation, until the outer, or chymified part, had passed into the duodenum, in successive parcels ; which, it is evident, would very much retard the process of digestion. As the food becomes more and more changed from its crude to its chymified state, the acidity of the gastric fluids is considerably increased— more so in vegetable than animal diet, — and the general contractile force of the muscles of the stomach is augmented in every direction ; giving the contained fluids an impulse towards the pylorus. It is probable, that fi'om the very commencement of chymification — ^fi:om the time that food is received into the stomach — until that organ becomes empty, portions 104 EFFECTS OF STOMACHIC CONTRACTIONS. of chyme are constantly passing into the duodenum, through the pyloric orifice, as the mass is presented at each successive revolution. I infer this from the fact that the volume is constantly decreasing. This decrease of volume, however, is slow at first ; but is rapidly ac- celerated towards the conclusion of digestion, when the whole mass becomes more or less chyraified. This ac- celerated expulsion appears to be effected by a peculiar action of the transverse muscles, or rather of the traTis- verse band, as described by Spallanzani, Haller, Cooper^ Sir E. Home, and others, in their experiments on ani- mals. This band is situated near the commencement of the more conieally shaped part of the pyloric extremity? three or four inches from the smaller end. In attempt- ing to pass a long glass-thermometer tube, through the aperture, into the pyloric portion of the stomach, during the latter stages of digestion, a forcible contraction is first perceived at this point, and the bulb is stopped. In a short time, there is a gentle relaxation, when the bulb passes without difficulty, and appears to be drawn, quite forcibly, for three or four inches, towards the pyloric end. It is then released, and forced back, or suffered to rise again ; at the same time giving to the tube a circular, or rather spiral motion, and frequently revolving it com- pletely over. These motions are distinctly indicated^ and strongly felt, in holding the end of the tube between the thumb and finger ; and it requires a pretty forcible grasp to prevent it from slipping from the hand, and be- ing drawn suddenly down to the pyloric extremity. When the tube is left to its own direction, at these periods of EFFECTS OF STOMACHIC CONTRACTIONS. 105 contraction, it is drawn in, nearly its whole length, to the depth of ten inches : and when drawn back, requires con- siderable force, and gives to the fingers the sensation of a strong 5wc^zow-power, like drawing the piston from an exhausted tube. This ceases as soon as the relaxation occurs, and the tube rises again, of its own accord, three or four inches, when the bulb seems to be obstructed from rising further; but if pulled up an inch or two, through the stricture, it moves freely in all directions in the cardiac portions, and mostly inclines to the splenic extremity, though not disposed to make its exit at the aperture. Above the contracting band, and towards the splenic portion of the stomach, the suction or grasping motion is not perceptible ; but when the bulb is pushed down to this point, it is distinctly felt to be grasped, and confined in its movements. These peculiar motions and contractions continue un- til the stomach is perfectly empty, and not a particle of food or chyme remains ; when all becomes quiescent again. If the bulb of the thermometer be suffered to be drawn down to the pyloric extremity, and detained there for a short time, or if the experiment be repeated too fre- quently, it causes severe distress, and a sensation like cramp or spasm, which ceases on withdrawing the tube ; but leaves a sense of soreness and tenderness at the pit of the stomach. The peculiar contractions and relaxations, mention- ed above, succeed each other, at irregular intervals of 106 ORDER OF CONTRACTION IN THE from two to four or five minTites. Simultaneously with the contractions, there is a general shortening of the fibres of the stomach. This organ contracts upon itself in every direction ; and its contents are compressed with much force. The valvular portion of the stomach is firmly thrust into the aperture, closing the orifice, pre- venting the egress of aliment, and obstructing the view of the interior. During the intervals of relaxation, the rugae perform their vermicular actions, the undulatory motions of the fluids continue, and the alimentary and chymous masses appear, revolving as before, promiscu- ously mixed, through the splenic and cardiac portions. All these facts, taken together, will, I think, rationally admit of the following explanation. The longitudinal muscles of the whole stomach, with the assistance of the transverse ones of the splenic and central portions, carry the contents into the pyloric extremity. The circular or transverse muscles contract progressively, from left to right. When the impulse arrives at the transverse hand, this is excited to a more forcible contraction, and, closing upon the alimentary matter and fluids, contained in the pyloric end, prevents their regurgitation. The muscles of the pyloric end, now contracting upon the contents detained there, separate and expel some portion of the chyme. It appears that the crude food excites the con- tractile power of the pylorus, so as to prevent its passage into the duodenum, while the thinner chymified portion is'pressed through the valve, into the intestine. After the contractile impulse is carried to the pyloric extre- mity, the circular band, and all the transverse muscle s? MUSCULAR FIBRES OF THE STOMACH. 107 become relaxed, and a contraction commences in a re- versed direction, from right to left, and carries the con- tents again to the splenic extremity, to undergo similar revolutions. It would appear, then, that the discharge of the chyme from the stomach, is effected by mechanical impulse. But, I confess, I do not like to give an opinion. I state the circumstances as they have occurred. The idea of mechanical force, I admit, is liable to objection ; but, perhaps, not more so than that of the selecting power of the pylorus. Whatever bias I may have in favour of the former method, has been forced upon me by the deduc- tions of experiment and observation. ( 108 ) CHAPTER VIII. OF CHYLIFICATION, AND THE USES OF THE BILE AND PANCREATIC JUICE. Passage of chyme into the duodenum — and there converted into chyle by the agency of the bile and pancreatic juice — Chyle always the same in health — Changes occurring in the duo- denum. As food becomes chymified by the gastric juice, the contractile motions of the stomach send it into the duo- denum to receive further changes preparatory to its assi- milation to the circulating fluids of the system by the lac- teal absorbents. It is at first slowly received into this organ from the stomach, but, during the later stages of chymification, its transmission becomes more accelerated. The duodenum is so constituted, that the passage of the chyme through it is considerably retarded ; and hence, in some pathological conditions of the system, the pres- sure on that organ from repletion is considerable, and frequently produces great pain and distress. The vermicular motions of this and the other intes- tines are propagated from the stomach, and are con- tinued, after this organ has discharged all its contents, by the contained fluids, until the whole becomes assimi- lated. They are more or less rapid, varying at different sections of the canal, of which it is not necessary to par- CONVERSION OF CHYME INTO CHYLE. 109 ticularize. These motions are excited by the stimulus of the chyme, and occur at intervals, on the introduction of each quantity passed through the pylorus. The chymous mass is not changed until it arrives at, or passes the mouth of, the ductus choledochus, when the liver and pancreas are excited to discharge their re- spective fluids. These mix with the chyme, and pro- duce an essential alteration in its sensible and chemical properties. At this point the lacteal absorbents com- mence. That the change from a chymous to a chylous stage, is effected by the operation of the bile and pancreatic juice, there can be no doubt. Of the nature of this change there is some diversity of opinion. Chyle is ge- nerally described as " a white opaque substance, con- siderably resembling cream in its aspect and physical properties," * though it is said to vary slightly, accord- ing to the kind of aliment which had been used. It is my impression, however, that pure chyle, taken from the lacteals of a healthy subject, and produced by natural food, is invariably the same substance in the same indi- vidual. Changes that have been observed must be reckoned as the effect of a pathological state of the sys- tem, or the absorption of a non-digesting substance. Me- dicines and other substances, which are not capable of digestion, are sometimes taken up by the lacteal absorb- ents, and may produce an alteration in the physical and chemical properties of chyle. It is possible that a small* proportion of oil may escape the action of the digestive * Bostock's Physiology, vol. ii. p. 392. 1 10 IN HEALTH CHYLE IS ALWAYS THE SAME. apparatus, be absorbed by the lacteals, and produce the opaque, white colour, mentioned by authors as some- times appearing. Countenance is given to this sugges- tion by the fact, that the more opaque-coloured parts of chyle are found floating on the surface, and that it is al- ways discovered after the ingestion of oily food. At other times it is uniform in its colour and consistence, whatever colouring matter may have been contained in the food. I wish to be understood to say, that every species of aliment produces the same kind of nutrient principles. With the view of attempting an investigation of this sub- ject, as has been previously mentioned, I instituted some imperfect experiments and examinations. From the re- sult, see Experiments, Second Series, from 47th to 56th. By the addition of bile and dilute muriatic acid, and sub- sequently pancreatic juice, to chyme formed in the arti- ficial way, as well as in the stomach, it separated into three distinct parts, a reddish-brown sediment at the bot- tom, a whey-coloured fluid in the centre, and a creamy pellicle at the top. Each repetition of the experiment produced a similar result, though not exactly alike in all. The central portion I suspect to be imperfectly-formed chyle. The sediment, fi'om its appearance and the coarseness of its particles, I judge is incapable of being acted on or taken up by the absorbents ; the creamy or oily pellicle is not only liable to the same objection, but is in too small proportion to the ingesta. The fluid part is fitted, by its fluidity, for the ready action of the ab- sorbents, and is, moreover, in sufficient quantity for the CHANGE WHICH OCCURS IN DUODENUM* 111 purposes of nutrition. The change of colour and con- sistence is probably effected in the lacteal glands and vessels. The sediment and pelHcle, I apprehend, are both excrementitial. The " irregular filaments" attached to the valvuiae conniventes, mentioned by Magendie, and which he concluded to be imperfectly-formed chyle, were undoubtedly portions of the creamy pellicle found in the experiments referred to. But what is the nature of the changes effected in the duodenum ? Aliment, after being introduced into the stomach, is dissolved in the gastric juice, and forms a new compound with this fluid. The constituent ele- ments of food are various. When compounded with the gastric juice, they may, nevertheless, be said to form a simple compound, or a gastrite of aliment. I am indiffe- rent about terms ; and this will as well convey my mean- ing as any other. When this gastrite is introduced into the duodenum, and mixed with the hepatic and pancrea- tic fluids, are we not warranted, from all the facts that have been observed, in saying, that there is a general play of chemical affinities in that organ, separating the nutrient principles, and forming various new compounds from the elements of each ? The chymous mass changes its colour, and loses its acidity. There is a sensible ex- trication of gas, as observed by Magendie and others.* In the stomach oxygen is found mixed with a small pro- portion of hydrogen. In the intestines an increased pro- portion of hydrogen exists, with carbonic acid, nitrogen, • The escape of gas is generally observable in mixing these fluids with chyme in my experiments. 112 CHANGE WHICH OCCURS IN DUODENUM* kc.f but no oxygen. Does not the acid of the chyme unite with the alkalis of the bile, and form new com- pounds ? And do not other equally important changes take place ? This subject, I confess, is obscure, and per- haps will not admit of a very perfect investigation. The constant agitation which is maintained in the in- testines preserves the chyle in a state of perfect admix- ture with the other fluids until absorption has taken place. By standing at rest the separation mentioned above is evident and perfect. It has been supposed that the mucus of the intestines has some agency in the formation of chyle. But I am disposed to think with Professor Dunglison and others, that the use of the mucus is to lubricate the in- ternal coat of the intestines, and perhaps to dilute their contents. It has been suggested that digestion can be perfected in the duodenum and lower bowels when the food has not been submitted to the action of the stomach and its fluids. In two experiments by Magendie, one failed, and the other was attended with partial success. Too much reliance ought not to be placed on experiments that re- quire such severe and cruel vivisections as were resorted to in these cases. It is possible, as suggested by Dun- glison, that the presence of crude aliment in the duo- denum may excite the discharge of gastric juice in the stomach, its expulsion into the duodenum, and its conse- quent action on the food, before it is affected by the bile and pancreatic juice. Or it may be that the upper part CHANGE WHICH OCCURS IN DUODENUM. 113 of the duodenum is furnished with vessels which secrete a fluid similar to gastric juice. Experiments have also been instituted with the view of ascertaining whether chyle can be formed without the admixture of the hepatic and pancreatic fluids with vari- ous results. Brodie ascertained, bj' tying the ductus communis choledochus in young cats, that the process of chylification was prevented, and that no chyle was found in the intestines. Magendie, Leuret, and Lassaigne, on tying this duct, discovered matter of " a rosy yellow co- lour," which afforded, on analysis, the same constituents of chyle, although the animals which were the subjects of the operation had been kept some time without food. There is certainly an apparent discordance in these re- ports. But it is possible they may be explained and reconciled. It is well known that the absorbents are ac- tive during a protracted fast (as in these last experi- ments), and are constantly taking up the cellular sub- stance, for the purpose of supplying the bloodvessels with these broken-up solids of the system. Emaciation is the effect of absorption. The lacteals, like other ab- sorbents, have undoubtedly their appropriate stimulus ; but, if that be withholden, they will feed on other sub- stances, the cellular and other solid parts within their reach. If such be the case, it will account for the rosy- coloured fluid found in the lacteals by Magendie and others. K EXPERIMENTS AND OBSERVATIONS, &c. EXPERIMENTS, &a FIRST SERIES. EXPERIMENT 1. August 1. 1825 — At 12 o'clock, a.m., I introduced through the perforation, into the stomach, the following articles of diet, suspended by a silk string, and fastened at proper distances, so as to pass in without pain — viz. : — a piece of high seasoned a la mode beef, a piece of raio salted fat pork, a piece of raw salted lean beef, a piece of boiled salted beef a piece of stale bread, and a bunch of raw sliced cabbage ; each piece weighing about two drachms ; the lad continuing his usual employment about the house. At 1 o'clock, P.M., withdrew and examined them — found the cabbage and bread about half digested ; the pieces of meat unchanged. Returned them into the stomach. At 2 o'clock, P.M. withdrew them again — found the cabbage, bread, pork, and boiled beef all cleanly digest- ed,* and gone from the string ; the other pieces of meat * These experiments are inserted here, as they were originally taken down in my note-book, with very little alteration of phraseo- 118 EXPERIMENTS ON THE DIGESTION but very little affected. Returned them into the stomach again. At 2 o'clock P.M.* examined again — ^found the a-la- mode-beef partly digested ; the raw beef was slightly macerated on the surface, but its general texture was firm and entire. The smell and taste of the fluids of the sto- mach were slightly rancid ; and the boy complained of some pain and uneasiness at the breast. Returned them again. The lad complaining of considerable distress and un- easiness at the stomach, general debility and lassitude, with some pain in his head, I withdrew the string, and found the remaining portions of aliment nearly in the same condition as when last examined ; the fluid more rancid and sharp. The boy still complaining, I did not return them any more. August 2. — The distress at the stomach and pain in the head continuing, accompanied with costiveness, a depressed pulse, dry skin, coated tongue, and numerous white spots, or pustules, resembHng coagulated lymph, spread over the inner surface of the stomach, I thought it advisable to give medicine ; and, accordingly, dropped into the stomach, through the aperture, half a dozen calomel pills ^ four or five grains each; which, in about three hours, had a thorough cathartic effect, and removed logy, and none of the sense. Subsequent experiments have some- times convinced me of errors in former ones. When this has been the case, I have generally made the corrections in the way of re- marks, or observations, as in this experiment. • There is evidently an error in repeating the same hour here ; but it is impossible to correct it — Editor. OF A MIXED MEAL. 119 all the foregoing symptoms, and the diseased appearance of the inner coat of the stomach. The effect of the me- dicine was the same as when administered in the usual way, by the mouth and oesophagus, except the nausea commonly occasioned by swallowing pills. Remarks, — This experiment cannot be considered afair test of the powers of the gastric juice. The cabbage, one of the articles which was, in this instance, most speedily dis- solved, was cut into small fibrous pieces, very thin, and necessarily exposed on all its surfaces to the action of the gastric juice. The stale bread was porous, and, of course, admitted the juice into all its interstices ; and probably fell from the string as soon as softened, and before it was completely dissolved. These circumstances will account for the more rapid disappearance of these substances, than of the pieces of meat, which were in entire solid pieces when put in. To account for the disappearance of the fat pork, it is only necessary to remark, that the fat of meat is always resolved into oil, by the warmth of the stomach, before it is digested. I have generally ob- served that when he has fed on fat meat or butter, the whole superior portion of the contents of the stomach, if examined a short time after eating, will be found covered with an oily pellicle. This fact may account for the dis- appearance of the pork fi-om the string. I think, upon the whole, and subsequent experiments have confirmed the opinion, that fat meats are less easily digested than lean, when both have received the same advantages of comminution. Generally speaking, the looser the tex- 120 EXPERIMENTS ON ture, and the more tender the fibre, of animal food, the easier it is of digestion. This experiment is important, in a pathological point of view. It confirms the opinion, that undigested por- tions of food in the stomach produce all the phenomena of fever ; and is calculated to vrarn us of the danger of all excesses, where that organ is concerned. It also ad- monishes us of the necessity of a perfect comminution of the articles of diet. EXPERIMENT 2. August 7. — At 11 o'clock, a.m., after having kept the lad fasting for seventeen hours, I introduced the glass - tube of a thermometer (Fahrenheit's) through *the perfo- ration, into the stomach, nearly the whole length of the stem, to ascertain the natural warmth of the stomach. In fifteen minutes, or less, the mercury rose to 100°, and there remained stationary. This I determined by mark- ing the height of the mercury on the glass with ink, as it stood in the stomach, and then withdrawing it, and placing it on the graduated scale again. I now introduced a gum-elastic (caoutchouc) tube, and drew off one ounce of pure gastric liquor, unmixed with any other matter, except a small proportion of mucus, into a three ounce vial. I then took a solid piece of boiled^ recently salted beef, weighing three drachms, and put it into the liquor in the vial ; corked the vial tight, and placed it in a saucepan filled with water, raised to the temperature of 100°, and kept at that point, on a nicely regulated sand-bath. In forty minutes digestion had distinctly commenced over the surface of the meat DIGESTION OUT OF THE STOMACH. 121 \xi fifty minutes the fluid had become quite opaque and cloudy ; the external texture began to separate and be- come loose. In sixty minutes chyme began to form. At 1 o'clock p. M. (digestion having progressed with the same regularity as in the last half hour), the cellular texture seemed to be entirely destroyed, leaving the muscular fibres loose and unconnected, floating about in fine small shreds, very tender and soft. At 3 o'clock, the muscular fibres had diminished one half, since last exa- mination at 1 o'clock. At 5 o'clock, they were nearly all digested ; a few fibres only remaining. At 7 o'clock, the muscular texture was completely broken down, and only a few of the small fibres floating in the fluid. At 9 o'clock, every part of the meat was completely digested. The gastric juice, when taken from the stomach, was as clear and transparent as water. The mixture in the vial was now about the colour of whey. After standing at rest a few minutes, a fine sediment of the colour of the meat subsided to the bottom of the vial. ^ Experiment 3. August 7. At 1 1 A. M. I suspended a piece of heej\ exactly similar to that in the vial (Ex. 2.), into the sto- mach, through the aperture. At 12 o'clock m. withdrew it, and found it as much affected by digestion as that in the vial ; there was little or no difference in their appear- ance. Returned it again. At 1 o'clock p.m. I drew out the string, but the meat was all completely digested and gone. 122 EXPERIMENTS ON Remarks. — The effect of the gastric juice on the piece of meat suspended in the stomach, was exactly similar to that in the vial, only more rapid after the first half hour, and sooner completed. Digestion commenced on, and was confined to, the surface entirely in both situations. Agi- tation accelerated the solution in the vial, by removing the coat that was digested on the surface, enveloping the remainder of the meat in the gastric fluid, and giving this fluid access to the undigested portions. Experiment 4. August 8. — At 9 o'clock a.m., I drew off an ounce and a half of gastric juice into a three ounce vial, sus- pended two pieces of boiled chicken, from the breast and back, into it, and placed it in the same situation and tem- perature as in the second experiment, observing the same regularity and minuteness. Digestion commenced and progressed much the same as in the second experiment, but rather slower : Xhefowl appearing to be more difficult of digestion than thejiesk. The texture of the chicken being closer than that of the beef, the gastric juice appeared not to insinuate itself into the interstices of the muscular fibre so readily as into the beef, but operated entirely upon the outer surface, dis- solving it as a piece of gum-arabic is dissolved in the mouth, until the List particle was digested. The colour of the fluid, after digesting the chicken, was of a greyish-white, and more resembled a milky fluid than whey, which was the colour of the chyme from the beef. DIGESTION OUT OF THE STOMACH. 123 The contents of both vials, kept perfectly tight, re- mained free from any fcetor, acidity, or offensive smell or taste, from the time of the experiments (7th and 8th August) to the 6th of September ; at which time, that containing the solution of boiled beefhecdime very offen- sive and putrid ; while that containing the chyme from the boiled chicken was perfectly bland and sweet. Both were kept in exactly similar situations. Remarks. — It is perhaps unnecessary to make any com- ments on the result of the above experiments. Each one will make up his opinion from the facts. These demonstrate, at least, that the stomach secretes a fluid which possesses solvent properties. The change in the solid substances is effected too rapidly to be accounted for on the princi- ple of either maceration or putrefaction. I shall be able to shew, in some of the following experiments, that ali- ment undergoes the same changes in the stomach as are effected in the mode here adopted. The young man who was the subject of these experi- ments, left me about this time (September 1825) and went to Canada, the place of his former residence. The experiments were consequently suspended. ( 124 ) SECOND SERIES. Fort Crawford, Upper Mississippi, ^■^71^20. 1829. Alexis St Martin having returned from Canada, after an absence of nearly four years, with his stomach in the same or very similar condition as when he left me in September 1825, I continued to prosecute the gastric experiments which were commenced before he left me. With a view to ascertain the variations of temperature, if any there were, in the interior of the stomach, under different circumstances and conditions of the system, and vicissitudes of the atmosphere, I instituted the following experiments. Experiment 1. December 6. 1829. At 9 o'clock a.m. I introduced the glass-tube of a thermometer (Fahrenheit's) through the artificial opening into the stomach, in a healthy and empty condition, nearly the whole length of the stem. In six or eight minutes, the mercury became stationary at 98°. Weather cloudy, damp, and almost raining ; ground wet, muddy, and thawing. Wind south and mild. Ther- mometer, in a north exposure, 63°. Commenced rain- ON THE TEMPERATURE OF THE STOMACH. 125 ing at 1 1 o'clock a. m. and continued all day, with op- pressive atmosphere. Experiment 2. December "J. — Introduced thermometer at the same hour as yesterday — circumstances of stomach the same. Mercury at 98°. Weather cloudy ; atmosphere damp ; wind N. W. and light ; thermometer 27°. Experiment 3. December 8. — Introduced thermometer at 9 o'clock A. m. — circumstances of stomach same as yesterday. Mercury stationary at 99°. Weather clear ; atmosphere dry ; wind S. W. and light ; thermometer 13°. Experiment 4. December 9. — Introduced thermometer at 9 o'clock, A. M — circumstances similar. Mercury stationary at 99°- Weather clear ; atmosphere dry ; wind W. and light ; thermometer 10°. Experiment 5. January 24. 1830. — Introduced thermometer at 3 o'clock p. m. Weather clear and cold ; thermometer 8° below 0 ; wind N. W. and light ; stomach empty and coats healthy. Mercury stationary at 100°. Experiment 6. January 25. — Introduced thermometer at 8 o'clock a.m. Weather clear; wind S. W. and light; thermo- meter 2° ; stomach empty. Mercury stationary at 100°. 126 ON THE TEMPERATURE OF THE STOMACH. At 10 o'clock A.M. (one hour after eating a breakfast of pork and bread) introduced thermometer again. Mer- cury stationary at 100°, as at 9 o'clock, before eating. Experiment 7. March 17. — At 10 o'clock a.m. introduced thermo- meter. Weather rainy and foggy ; wind S. W. and Hght ; thermometer 38° ; stomach empty, having eaten nothing since 7 o'clock last evening. Mercury station- ary at 99°. Experiment 8. March 18. — At 8 o'clock a. m. introduced thermo- meter. Mercury stationary at 1 00°. Weather clear ; wind N. W. ; thermometer 6°. At 9 o'clock, breakfasted on meat, biscuit, and butter with coffee. Temperature of the stomach, immediately before eating, 100° ; thirty minutes after finishing break- &st, the temperature had risen to 102°. Digestion ra- pidly advancing. Remarks. — It appears, from the above experiments, that the variations of the atmosphere produce effects upon the temperature of the stomach, — a dry atmosphere increasing, and a humid one diminishing it. What would be the effect of copious perspiration, in warm weather, on the tempe- rature of the stomach ? Would that of the interior of this organ be lessened by evaporation ? I regret that sufficient experiments have not been made fully to satisfy these inquiries. From one or tv*^o experiments, it would SUPPOSED ACCUMULATION OF GASTRIC JUICE. 127 seem that the heat of the stomach was increased during the active period of digestion. This, however, was pro- bably owing to exercise immediately after eating, though not particularly observed and noted at the time. Subse- quent experiments have not shewn this result. On the contrary, the temperature has been found to be the same in its full and empty state. The ordinary temperature of the healthy stomach may be fairly estimated at 100° Fahrenheit. Some allowance ought probably to be made in these experiments for im- perfect instruments. It appears, from subsequent exami- nations, that there is probably some difference of tempe- rature in different regions of the stomach, it being higher at the pyloric than at the splenic end. See subsequent experiments and observations. To ascertain whether the gastric juice be accumulated in the stomach during periods of fasting, or even from the immediate and direct influence of hunger, I made the following experiments. Experiment 9. December 5. 1829. — At 8 o'clock a. m., after twelve hours' abstinence from either food or drinks, I introduced, at the perforation, a gum-elastic tube, and drew off a drachm or two only of the gastric juice. There was no accumulation in the stomach. Experiment 10. December 12 At 3 o'clock p. m. introduced tube ; could procure two or three drachms only ; this was se- 128 EXPERIMENTS ON THE SUPPOSED creted on the irritation of the tube. Stomach contained none in a free state. Experiment 11. December 14. — At 10 o'clock P. m., after eighteen hours' fasting, introduced tube and drew off one and a half ounces of gastric juice. It was clear, and almost transparent ; tasted a little saltish and acid when applied to the tongue, similar to thin mucilage of gum-arabic, slightly acidulated with muriatic acid. There was no ac- cumulation in the stomach when the tube was intro- duced. Experiment 12. March 13. 1830 At 10 o'clock a. m. stomach empty ; introduced tube, but was unable to obtain any gastric juice. On the application of a few crumbs of bread to the inner surface of the stomach, the juice be- gan slowly to accumulate, and flow through the tube. The crumbs of bread adhered to the mucous coat, soon became soft, and began to dissolve and digest. On view- ing the villous membrane before applying the bread crumbs, the mucous coat and subjacent follicles only could be observed ; but, immediately afterwards, small sharp papillae, and minute lucid points, situated in the in- terstices of, and less than, the mucous follicles, became visible, from which exuded a clear transparent liquor. It then began to run through the tube. Experiment 13. March 18 — At 6 o'clock p. m., after fasting from 8 ACCUMULATION OF GASTRIC JUICE. 129 o'clock, A. M.j introduced tube ; obtained one and a half ounces gastric juice, after having kept up the irritation by moving the tube from point to point for twelve or fif- teen minutes. No accumulation of free juice in the sto- mach. Experiment 14. January 26. 1 831. — At 9 o'clock a. m. stomach empty ; extracted one ounce gastric juice slowly through the tube, with the usual admixture of mucus. Introduced food, and it began directly to flow more freely through the tube. Experiment 15. January 27. — At 8 o'clock a. m. — stomach empty ; introduced elastic tube, and obtained one and a half drachms of gastric juice by very slow distillation. Ap- plied crumbs of bread to the villous coat, and the juice began immediately to flow freely through the tube. Experiment 16. March 6 — At 8 o'clock a. m., extracted two ounces gastric juice, and added it to two ounces of Madeira wine. No visible change was produced ; no coagulse formed. They united like pure water and wine. Heat produced no other effect. Experiment 17. March 7. — At 6 o'clock p. m. stomach empty ; ex- tracted one and a half ounces of juice, and mixed it with the same quantity of Jamaica spirits. Effect same as with wine. 130 SUPPOSED ACCUMULATION OF GASTRIC JUICE. Experiment IS. March 8.— At 8 o'clock a. m. stomach empty ; ex- tracted one and a half ounces of gastric juice. Experiment 19. March 12. — At 9 o'clock a. m. stomach empty; ex- tracted one and a half ounces of gastric juice. Put this in a bottle. Experiment 20. March 1 3 — At 1 1 o'clock a. m. stomach empty ; ex- tracted two ounces of juice. Experiment 21. March 14 — At 12 o'clock a.m. stomach empty; ex- tracted two ounces of juice. Experiment 22. March 15 — At 4 o'clock, p.m. stomach empty; ex- tracted one and a half ounces gastric juice. Experiment 23. March 1 6 At 5 o'clock p. m. introduced tube ; could obtain no clear gastric juice. A little acrid fluid and frothy mucus only could be extracted. Villous mem- brane red and dry. St Martin complained of some headach, pain and distress about the scrobiculus cordis, lassitude and loss of appetite. Directed him to take half an ounce o^ tinc- ture of aloes and myrrh at 9 o'clock p. m. This moved his bowels several times next morning. Little or no change REFLECTIONS ON THESE EXPERIMENTS. 131 was apparent in the appearance of the inner coat of the stomach ; if any, it was a Httle more moist, and a shade paler, after the operation of the tincture. Gastric juice could again be obtained, but in less than usual quantity. Remarks. — It would seem from the preceding experi- ments, that the stomach contains no gastric juice in a free state, when aliment is not present. Any digestible or irritating substance, when applied to the internal coat, ex- cites the action of the gastric vessels. Hence, I infer that the fluid, in these experiments, was incited to dis- charge itself by the irritation of the tube used in extract- ing it. If, as is contended for by some, a part of the fluid be discharged into the stomach during a fast, I see no rea- son why nature should withhold the other part. If we may be allowed to argue, independent of more certain data, one great objection to the opinion that the stomach contains gastric juice, in a free state, when food is with- holden from it, exists in the danger of its passing out through the pyloric orifice, and thus depriving the suc- ceeding meal of the benefit of its solvent action. It is probable that the pyloric orifice opposes no resistance to its egress, but is obedient to its summons. In this way we may account for its admitting chyme, which is an ad- mixture, or rather combination, of gastric juice and food to obey the expulsive motions of the stomach and pass out. They both appear to excite the peculiar contrac- tion of the pyloric end of the stomach, mentioned in a for- mer part of this work. Besides, there would be danger 132 ARTIFICIAL DIGESTION. of the gastric juice being weakened by the introduction of large quantities of water or other fluids in the inter- vals of eating, and thus lose its energy and concentrated solvent properties. The last experiment has considerable pathological im- portance. In febrile diathesis very little or no gastric juice is secreted. Hence the importance of withholding food from the stomach in febrile complaints. It can af- ford no nourishment, but is actually a source of irrita- tion to that organ ; and, consequently, to the whole sys- tem. No solvent can be secreted under these circum- stances, and food is as insoluble in the stomach as lead would be under ordinary circumstances. The following, and most of the subsequent experiments of this series, were instituted with the view of ascertain- ing the relative difference between natural and artificial digestion ; to demonstrate the performance of digestion out of the stomach, by the gastric juice ; and, also, the continuation of the natural process, when taken out du- ring the period of chymification. EXPERIMENT 24. December 14. 1829 At 1 o'clock, p.m., I took one and a half ounces of gastric juice, fresh from the stomach, after eighteen hours fasting, into an open mouthed vial, put into it twelve drachms recently salted beef (boiled), and placed it in a basin of water, on a sand-bath, and kept it at about 100° (Fahrenheit) with frequent gentle ARTIFICIAL DIGESTION. 133 agitation. Digestion commenced in a short time on the surface of the meat, and progressed in that manner uni- formly for about six hours, when its solvent action seemed to cease. The meat was at this time nearly half dissolved ; the texture of the central portion considerably loosened and tender, resembling the same kind of aliment when ejected, partly digested, from the stomach, some hours after being swallowed, as frequently seen in cases of in- digestion. The vial, continuing in the same situation, its contents varied considerably in their sensible qualities. In twenty- four hours, the digested portion separated into a reddish- brown precipitate, and whey-coloured fluid. I now separated the undigested from the chymous por- tion, by filtration, through thin muslin. When squeezed dry, it weighed five drachms, two scruples, and eight grains, which, deducted from the twelve drachms of meat put in at first, leaves six drachms and twelve grains, di- gested in twelve fluid drachms of gastric juice. This experiment was conducted with as much precision and integrity of observation as possible, with the tempe- rature of the digesting bath kept as near blood heat as was practicable to regulate and continue artificial warmth, the thermometer varying during the time, fi'om90° to 100°. In this experiment, it appears that it took twelve drachms of gastric juice to digest six drachms and twelve grains of aliment. No certain rule can, however, be given. Allowance must be made for the purity of the fluid, or its admixture with mucus and other secretions ; for it is altogether probable that there are great varia- 134 ARTIFICIAL DIGESTION. tions in it, in this respect, as well as in all the other se- cretions of the system. It is probable, also, that differ- ent kinds of diet require different proportions of gastric juice for their solution. That its action is similar to that of other chemical agents, I have no doubt. A given quantity ofthejftuid acts on a definite proportioii of ali- ment, when it becomes saturated, and is inadequate to produce any further effect. There is always disturbance of the stomach when more food has been received than there is gastric juice to act upon it. EXPERIMENT 25. December 16. At 2 o'clock, p. m Twenty minutes after having eaten an ordinary dinner of boiled salted beef bread, potatoes, and turnips, and drank a gill only of pure ivater, I took from his stomach, through the ar- tificial opening, a gill of the contents, into an open mouthed vial. Digestion had evidently commenced, and was perceptibly progressing at the time. This vial and contents were immediately placed in a basin of water, on the sand-bath, at 90° or 100°, and continued there for five hours. The digestion of the contents continued to progress until all was completely chymified. At 7 o'clock — five hours after eating his dinner — I took out a gill of pure chyme ; no particles of undigested food appearing in the mixture. Very little difference was perceptible between this last parcel and that in the vial, digesting on the bath. The stomach had digested a little faster and more perfectly than the vial. FOOD DIGESTED WHEN TAKEN FROM STOMACH. 135 JRemarks. — In this experiment, it seems, that a quantity of aUment taken out of the stomach twenty minutes after having been eaten, had a sufficient admixture of gastric juice to ensure its perfect digestion when placed on the bath. An ordinary moderate meal, taken into a healthy stomach, is sooner disposed of than most physiologists are aware of ; and in this case, it is probable that a sufficient quantity of gastric juice had been secreted in twenty mi- nutes, to digest the whole quantity of aliment in the sto- mach. When a large quantity has been received, though the powers of the stomach may be sufficient, ultimately, to dispose of it, it would undoubtedly be found that a por- tion taken from the stomach a few minutes after having been eaten, would not contain a sufficient quantity of gas- tric juice to digest it perfectly. It is possible that the portion presented at the perforation may be in a more advanced stage of digestion than the rest of the mass, and consequently lighter, and float on the surface of the more solid portions of the food. In ordinary cases, such would be found to be the case ; but when much fat meat or oily food has been used, the oil always maintains an ascen- dancy in the gastric cavity. EXPERIMENT 26. January 1 1 . 1830. — At 3 o'clock, p. m., dined on bread and eight ounces oi recently salted lean beef, four ounces o^ potatoes, and four ounces of turnips, boiled. In fifteen minutes, took out a portion of the contents of the stomach. The meat made its appearance in an incipient state of digestion. 136 DIGESTION IN AND OUT OP THE At 3 o'clock 45 minutes, took out another portion. The meat and bread only appeared, in a still more ad- vanced stage of digestion. The texture of the meat was, at this time, broken into small shreds, soft and pulpy, and the fluid containing it had become more opaque,^ and quite gruel-like, or rather glutinous, in appearance. I put this second parcel in a vial, and placed it in water, on the sand-bath, at the temperature of the stomach (100° Fahrenheit) as indicated by the thermometer im- mediately preceding its extraction, and continued it there. At 5 o'clock, took out another quantity. Digestion had advanced in about the same ratio as from the first to the second time of extracting ; and when compared with the second parcel, contained in the vial on the bath, little or no difference could be perceived in them ; both were nearly in the same stage of digestion. That contained in the vial had advanced regularly and rapidly ; nearly all the particles of meat had disappeared, become chymi- fied, and changed into a reddish-brown sediment, sus- pended in the more fluid parts, with small particles, re- sembling loose white coagulae, floating about near the surface. On taking out the third parcel, small pieces of vege- tables appeared, in a partial stage of digestion. This was also put into a vial, and placed on a bath, with the second parcel, and the same uniform temperature (100°) kept up, with frequent gentle agitation. At 6 o'clock, p.m., digestion had progressed equally in both. The only dif- ference to be seen, was the particles of vegetables, in a less advanced stage than the meat. STOMACH COMPARED. 137 The contents of both vials, kept on the bath, and nearly in the same temperature, until the next morning, were completely digested, except the few small particles of vegetables which remained almost entire. The contents of the vials at this time, were of the consistence of thin jelly, and of a lightish-brown colour ; tasting peculiarly insipid, saltish and acid. After standing at rest awhile, the brownish sediment subsided towards the bottom, while small particles of whitish coloured loose coagulae floated about in the fluid above. The undigested particles of vegetables settled to the bottom. Remarks — In the Preliminary Observations, I have en- deavoured to maintain the proposition, that chyme is homo- geneous in its properties. It would seem from this and some other experiments, that it contains a sediment. This, however, it is believed, does not militate against its ho- mogeneous character. Many substances, that are gene- rally acknowledged to possess this character, deposit a sediment, on standing. The heavier parts subside, of course. It is not necessary to cite examples. It is pos- sible, also, that mixed food contains some adventitious, indigestible substances, which are not affected by the gastric juice. This experiment (26th) demonstrates the comparative digestibility of animal and vegetable diet. In extracting two parcels, one in fifteen minutes, and the other in three quarters of an hour, the meat only made its appearance, partially digested. In taking out a third portion, at 5 o'clock, two hours after being eaten, small particles of M 138 DIGESTIBILITY OF MEAT AND VEGETABLES. vegetables made their appearance. This experiment ap- pears to confirm the opinion, pretty generally entertained by medical men, that vegetables are less easily disposed of by the gastric organs, than animal or farinaceous sub- stances. With dyspeptics this is undoubtedly true, as experience every day teaches us ; and as their stomachs have the same organization as others, are governed by the same general laws, and are only modified by debility or disease, the conclusion is natural, that they should act on aliment in the same manner, in proportion to their strength, that the healthy stomach does. It may be inferred from this experiment, that the more perfectly chymified portions of food rise to the superior part of the stomach, as suggested in a previous obser- vation, and are consequently exposed at the perforation, fi'om whence parcels are taken for experiment and exa- mination. Experiment 27. March 17. At 12 o'clock, m drank half a pint of milk. In fifteen minutes, took a portion out of the sto- mach, in a fine, loosely coagulated condition, perfectly white, and suspended in a semi-transparent, whey-colour- ed fluid. I placed this on the bath, and it continued to digest for eight hours, when the coagulae were completely taken up. A very small proportion of light-coloured se- diment, settled loosely to the bottom of a cream-coloured sweetish fluid. At the same time that he drank the milk, I put one drachm of gastric juice, warm from the stomach, into twe» DIGESTION OF MILK. 139 drachms of tnilky and placed it on the bath, at the natu- ral temperature (100° Fahrenheit). In five minutes, pure white coagulae formed, which, in fifteen minutes, exactly resembled that taken out of the stomach. In twenty minutes, the same fine, loose coagulae were sus- pended in a similar liquid. These two drachms of milk, mixed with one drachm of pure gastric juice, out of the stomach, gave the same result, and exhibited the same appearance, in nearly the same time as that which was swallowed, and taken from the stomach. Scarcely a shade of difference could be perceived in four hours. Two drachms of milk, coagulated by acetous acid, pro- duced coagulae very similar to the other; but the wheyey part bore no resemblance, except in mere fluidity ; that formed from the gastric fluid being of an opaline, slight- ly yellowish cast, and the other thin, transparent, and watery. The coagulae formed by the gastric juice continued to digest regularly in their fluid, for about eight hours, when they were completely taken up, and converted into chyme. But the coagulae formed by the vinegar remain- ed in the same condition for forty-eight hours, with no other change except mere subsidence below the watery fluid. Remarks. — It is well known, and this experiment was not necessary to prove it, that milk is coagulated before it receives the solvent action of the gastric juice. But it has some degree of importance in demonstrating the fact, that a degree of solidity is necessary for the operation of this 140 PROGRESS OF DIGESTION agent. And it is a strong argument against the doctrine of digestion by the veins of the stomach. It has been maintained by some, that the veins take up the nutri- tious parts of the food, immediately on their introduction into the stomach. If so, it strikes me that they should do so, as it relates to this kind of aliment, while they are in a fluid state, and more susceptible of absorption by their mouths ; and not wait till they have become solidified. Wine, spirits, water, and other fluids, which conduce nothing towards alimentation, are neither coagulated, nor otherwise affected by the gastric juice. These fluids are not digested ; and probably enter the circulatory system without much change. It will be seen, by succeeding experiments, that other fluid, nutritive substances, particularly the albumen of eggs, are coagulated before they receive the solvent ac- tion of the gastric juice. Experiment 28. Jan, 25. 1831. At 1 o'clock, p. m., he ate a full din- ner of roast beefy potatoes^ heets^ and bread, and kept ex- ercising about his usual employment, as house servant. '^^Jri^.^ „.v^t 5 o'clock, 25 mins., Itook out a portion of the con- \t^^^ tents of the stomach. Digestion of the different articles of food had commenced, and considerably advanced. " A>^ %. '^^^ bread, reduced to a pultaceous condition, appeared v^ ' floating about in a reddish-brown fluid, of a glutinous consistence. A i^w small particles of the meat could also be seen in the fluid. None of the vegetables were discernible at this time. The fluids tasted slightly acid. Smw<»>'' EXHIBITED BY EXPERIMENT. 141 giving the flavour peculiar to dilute muriatic acid, and very slightly bitter. A few grains of carbonate of soda, thrown into a drachm or two of this fluid, produced a slight effervescence. At 4 o'clock, 20 mins took out another portion, a shade or two darker than the first. This dark colour of the chyme, I attributed to his having taken with his din- ner, some of the outside, scorched pieces of the beef. No distinct parts of the food could be seen at this time. Upon the surface of both parcels of fluids, floated a layer, of an oily or lardaceous consistence, which probably was the remains of the fat pork which he had eaten for his breakfast. The first parcel contained much more of this oily fluid than the last ; which leads me to think that a considerable portion of an imperfect chyme, formed from the pork taken at about 10 o'clock, for breakfast, remain- ed in his stomach when he ate his dinner ; and then mixed with this aliment, in an imperfect state of diges- tion. At 5 o'clock, 30 mins. — tried to extract another por- tion— could obtain nothing, except a little gastric juice. The chyme formed from his dinner appeared to have all passed from the stomach. Experiment 29. March 6. At 9 o'clock a. m. — breakfasted on venison steaky cranberry jelly and bread, and drank a pint o^ coffee. Twenty minutes after eating, I took a portion from the stomach, in an incipient stage of digestion. Placed this on the bath. 142 DIGESTION OF ALBUMEN AND EGG. At 9 o'clock, 45 mins. — I took another portion, in an advanced state of digestion — very few small particles of food were discernible. At 10 o'clock, 10 mins took out another portion, perfectly chymified. At 10 o'clock, 35 mins. — the stomach was entirely empty and clean — no chyme or aliment to be found in it. The breakfast, eaten at 9 o'clock, was all digested, and had passed through the pylorus, in one hour and thirty-five minutes. Remarks. — This is an example of the great rapidity of di- gestion in some instances. This rapidity depends upon vari- ous circumstances — principally upon moderation in quan- tity, and the digestible properties of the food used. From various trials, I am confident, generally speaking, that ve- nison is the most digestible of any diet of the fibrinous kind. In a few instances, it will be perceived, that other articles of diet were disposed of in a shorter period, than the venison was in this experiment. Experiment 30. March 7. Mixed two drachms of albumen of a fresh ^^^t with two drachms of gastric juice, warm from the stomach, and placed it on the bath, at the natural tem- perature. The juice and the albumen were so much alike in their appearance, when first mixed, that the change was not perceptible ; but in ten or fifteen mi- nutes, small white flocculi began to appear, floating about; and the mixture became of an opaque and whitish ap- pearance. This continued slowly and uniformly to in- crease, for three hours, at which time, the fluid had be- PROGRESS OF DIGESTION. 143 come of a milky appearance ; the small flocculi, or loose coagulae, had mostly disappeared, and a little light co- loured sediment subsided to the bottom. At the same time of the above experiment, he swal- lowed the white of two eggs, unmixed with any other food. The stomach was perfectly empty at the time. In thirty minutes, . I took out and examined a portion. It exhibited a similar appearance to that mixed out of the stomach, in the vial on the bath, only more rapid in its progress. In one hour and thirty minutes, I examined the cavity of the stomach, and found nothing but a little pure gastric juice. The albumen was completely digested and dis- posed of. EXPERIMENT 31. March 9 — At 8 o'clock, a. m. — Stomach empty — tem- perature 98° — took out two ounces gastric juice. Di- vided this into two equal parts, and put them into sepa- rate vials, to each of which I put equal quantities of roasted beef, placed one of them on the bath, at 99°? and the other in the open air, at 34°. I then put the same quantity of the meat into an equal quantity of clear water, and placed it with the cold gastric juice and meat, in the open air, at the same temperature. At 9 o'clock he had finished breakfasting on the same kind of meat, with the addition of warm light biscuit, butter, and a pint of coffee. Temperature of the stomach, immediately 5e/ore eating, 100°. In thirty minutes o/^er 144 PROGRESS OF DIGESTION IN eating, the temperature rose to 102°.* Digestion rapidly advancing. At 10 o'clock — took out a portion, partially digested ; the biscuit the most so of any part of the breakfast. Placed this on the bath. The meat contained in the vial of gastric juice on the bath, was, at this time, in about the same condition as that taken from the stomach ; very little difference could be perceived. The biscuit which he had eaten with his breakfast occasioned the only diflPerence ; that being reduced to a soft pulp. The meat in the cold gastric juice was, at this time, much less ad- vanced than either that in the warm juice, or in the por- tion taken from the stomach. That contained in the vial of water was merely macerated, and had no more appearance of digestion than what was effected by its being masticated, and mixed with the saliva, as were the other pieces of meat, before they were put into the gas- tric juice. At 10 o'clock, 45 minutes, I examined the stomach, but could find no distinct particles of food, and but very little chyme. His breakfast appeared to have been com- pletely digested, and had left the stomach. Temperature 100°. At 2 o'clock, p. M., the several parcels of meat placed in the gastric juice, on the bath, being about half digested, and appearing not to progress, I drew off twelve drachms of gastric juice from the empty stomach, and added four drachms to each, including the parcel taken from the * Probably the effect of exercise, but not noticed at the time. And OtJT OF TttE STOMACH. 145 Stomach, at 10 o'clock, a.m., that being in about the same state of chymification with the others on the bath. I continued the two on the bath, at 100°, and the others (cold gastric and aqueous fluids) on the shelf, at 34°. Digestion evidently recommenced in the parcels on the bath, and again regularly progressed, after the ad- dition of the second portions of the gastric juice ; and more rapidly in the vial containing the meat digesting in the gastric juice, taken out of the stomach first, than in the one containing the chymous portion, taken out at 10 o'clock A. M., one hour after having eaten. This parcel however, contained a solid piece of meat, which appeared to have been swallowed without being masticated ; and consequently, did not readily yield to the solvent action of the gastric juice. The juice was, also, in too small proportion completely to digest it. The vials containing the cold aqueous and gastric por- tions, placed on the shelf, were, at 4 o'clock, p. m., but very little changed, and much alike. These four parcels, after standing for twenty-four hours, and all suffered to get cool, exhibited the following ap- pearances : — The portion taken from the stomach at 10 o'clock, A.M., one hour after having eaten, was the most perfectly digested, and completely converted into a thick pultaceous mass, of a reddish brown colour, with the ex- ception of the piece of unmasticated meat, which re- mained entire and undigested. This emitted a sharp rancid smell, and was slightly bitter. The vial contain- ing the meat digesting in the gastric juice first taken out of the stomach, exhibited appearances very similar to the N 146 INFLUENCE OF HEAT ON DIGESTION. last, though the contents were less perfectly digested. It was not of so thick consistence, but gave the same sharp smell and bitter taste, with the addition of an empyreu- matic and slightly foetid flavoiu". The empyreuma, I at- tributed to a portion of the meat being a little dry and scorched, when first put in ; and the fcetor, to the tempe- rature of the bath, having been accidentally raised con- siderably above 100°, during the experiment. The cold gastric and aqueous portions very nearly re- sembled each other ; both macerated, but not digested ; differing essentially from the other two, in not exhibiting any appearance of chyme. The cold gastric juice had very little, if any, more effect on the meat, than the water, and retained its peculiar taste. Its colour was darkish- brown, while the latter was of a reddish-grey. At 9 o'clock A.M. of the 10th, I placed both of them on the bath, and continued them for twenty-four hours, at the natural temperature. An essential difference in the gas- tric liquor was produced, after being placed on the bath. Digestion evidently advanced ; the colour became lighter and lighter ; the meat diminished ; and a thin, light, paste-like liquor formed, as in the other two portions, at first placed on the bath. The aqueous portion exhibited no other appearance than that of simple maceration in warm water. At the end of the last twenty-four hours, on the bath, appearances of incipient putrefactive fer- mentation began to be manifested, as the evolution of smaU bubbles of foetid gas, and a change of colour fi'om a reddish to a greenish shade. A difference in the degrees of chvmification between GENERAL REMARKS. 147 the several parcels, was now very evident. The gastric portion, or that taken from the stomach, an hour after breakfast, was the most digested. The artificial, or that portion of the gastric juice and meat first placed on the warm bath, was next, and nearly as much digested ; though a difference was observable. The third or por- tion of gastric juice and meat, first placed in a cool situa- tion, after having been on the warm bath for six or eight hours, was the next, but considerably less digested than the second, while the fourth, or aqueous portion, exhibited no appearance of chymification. Hemarks It would seem from this experiment, that a certain degree of heat is necessary to the action of the gas- tric juice. One parcel of the meat, after being exposed to the cold gastric juice for twenty-four hours, exhibited very little change; but, being placed on the bath at the end of this time, digestion commenced, and advanced regularly as in the other parcels. It also appears that, after the process of digestion has ceased for want of a sufficient quantity of gastric juice, it will recommence on the addition of a fresh supply. It was necessary to add another quantity even to that portion taken out of the stomach to ensure its per- fect digestion. This, I think, is an evidence that the fluid is discharged into the stomach gradually and pro- gressively, according to the requirements of the aliment. If the portion left in the stomach had received, at the time the parcel was taken out, the whole quantity it was destined to receive^ it must have been imperfectly di- 148 INFLUENCE OF PASSION ON DIGESTION. gested, and have remained in the stomach precisely in the situation of that which was taken out and submitted to artificial digestion, which is proved not to have re- ceived its full supply for perfect digestion.* But subse- quent examination demonstrated that it was perfectly di- gested, and had nearly all passed out of the stomach in two hours. Hence, the conclusion is irresistible that it received an additional quantity after the portion was taken from the stomach one hour after eating. Experiment 32. March 1 2 At 8 o'clock a. m>, extracted one ounce of gastric juice. At 9 o'clock he breakfasted on fat pork, bread, and potatoes. One hour afterwards examined con- tents of stomach ; found a heterogeneous mixture resem- bling thick porridge. At 1 o'clock p. M., four hours after having eaten, took out a portion in a complete chymous state, without any entire particles of food to be seen. It was of a milky, or rather thin gruel-like consistence, and considerably tinged with yellow bile, a circumstance which I had but once before observed in my experiments upon him. And this * This inference must be received with some limitation, because, in other experiments, portions of food removed from the stomach within an hour after being swallowed, were entirely digested with- out any addition of gastric juice. In the instance in the text, two ounces of gastric juice had been extracted an hour before eating, which renders it next to certain that the usual qviantity could not be furnished for the meal at the time it was eaten ; so that even the experiment commented on scarcely warrants the inference of the author. — Editor. EFFECT OF DIVISION OF FOOD. 149 I supposed to have been the effect of violent anger, which occurred about the time of taking out this parcel. Remarks. — This experiment shews the effect of violent passion on the digestive apparatus. The presence of bile in this instance, was believed to be the effect of anger. In a healthy state of the stomach, and an equable frame of mind, this substance has seldom been found in the sto- mach. When so found, except under peculiar circum- stances of diet, it may generally be regarded as an indi- cation of either mental or corporeal disease, and may be considered a foreign and offending substance in that or- gan. I believe its effect is to change the properties of chyme (as it will be seen that it does in subsequent ex- periments), alter its homogeneous quality, and retard, or otherwise disturb, its due egress into its destined recep- tacle the duodenum. Experiment 33. March 13. — At 1 o'clock p. m — diined on roasted beefi bread, and potatoes. In half an hour examined contents of stomach ; found what he had eaten reduced to a mass resembling thick porridge. At 2 o'clock examined again — nearly all chymified — a few distinct particles of food still to be seen. At 4 o'clock, 30 minutes, chymification complete. At 6 o'clock examined stomach ; found no- thing but a little gastric juice tinged with bile. Experiment 34. March 14 At 8 o'clock, 15 minutes, introduced two 150 DIGESTION OF MILK AND BREAD. ounces of rare^ roasted beef, suspended by a string, into the stomach ; and, at the same time, put one drachm of the same kind of meat into twelve drachms of gastric juice, contained in a vial, and put it into his bosom. The piece in his stomach, examined every hour till 12 o'clock A. M., exhibited an uniform, but very slow process of di- gestion, confined entirely to the surface of the meat. In four hours about half of it only was dissolved and gone. That in the bosom at the same time digested still slower, owing probably to the circumstances, that the fluid in the vial had been taken out when the stomach was in a mor- bid condition, and had been permitted to get cold, even to the freezing point. This last circumstance, however, was probably of less importance than the other. The meat in the stomach was too much confined by the string ; was not permitted to move about freely in the gastric fluids by the natural motions of the stomach ; and, con- sequently, did not digest so fast as it otherwise would have done. Another circumstance or two may also have contributed to interrupt the progress of digestion, such as anger and impatience, which were manifested by the subject during this experiment. Remarks. — This experiment shews the necessity of a perfect comminution of the articles of diet. The gastric juice acted very slowly on a large solid piece of meat. Di- gestion or solution was confined entirely to the outer sur- face. This, in addition to the other causes mentioned above, produced the delay in digestion. why sudden changes are hurtful. 151 Experiment 35. March 14. — At 12 o'clock m., ate a. pint o£milk and four ounces of bread. Examined storaach in thirty mi- nutes ; found the milk coagulated, and the bread reduced to a soft pulp, floating in a large proportion of fluid. At 1 o'clock, 30 minutes, took out and examined a portion ; found it a thick pultaceous mass of bread, coa- gulee, and fluid, of a milky colom*, slightly bitter taste, and acid smell. Placed it on the bath, where it continued to become more and more milky for an hour, when every particle seemed to be reduced to a rich fluid mass, re- sembling milk porridge. The portion taken out thirty minutes after having been eaten and kept on the bath, retained the appearance of the gastric fluid, with distinct flocculi of bread and coa- gulae floating about and suspended in the fluid, and a lit- tle coarse precipitate at the bottom after standing at rest a while. ^ At 2 o'clock — examined stomach ; found it nearly empty. The bread and milk appeared to have been dis- posed of, and were gone from the stomach. Hemarks, — In this experiment it took two hours for the digestion of a meal of bread and milk, something shorter than the usual time for the disposal of an ordinary meal. For those who have healthy and unsophisticated stomachs, milk appears to be one of the best articles of diet we pos- sess. It is less stimulating than flesh, and more nutritious titan vegetables. For persons who are disposed to py- rexial complaints, and who are not obliged to perform 152 DIGESTION OF SOUP. hard and exhausting labour, it is the most appropriate diet. But the stomach is a creature of habit. It can be- come accustomed to any kind of diet ; and sudden changes are Hable to derange its healthy actions. To those accustomed to what is called high living, such as strong meats, strong drinks, and high seasoned food, of all kinds, the transition to a milk diet, which contains a considerably lowered stimulation, would probably be an imprudent change. When necessary, the change should be so gradual, that the stomach should, by degrees, be- come accommodated to it« Experiment 36. At 2 o'clock, 30 minutes, dined on fresh beef and vege- table soup^ and four ou7ices of bread. At 3 o'clock, 30 minutes, examined contents of sto- mach,— found a pulpous mass^ of the consistence of thick gruel, and of a semi- gek^inous appearance. The soup appeared to have had its more fluid parts absorbed ; for it was at this time much more consistent than when eaten. It was even thicker than the contents of the stomach usually are, after eating more solid food. Placed this on the bath. At 5 o'clock, took out another portion, of a whitish colour, and more paste-like consistence, mixed with a little thin transparent yellowish fluid, of an acid taste. The thick part had the flavour of bile but not the colour. Remarks. — Here the uniform laws with respect to liquid diet, appeared to govern the action of the gastric juice. DIGESTION OF VARIOUS SUBSTANCES. 153 The soup could not be digested until it was formed into a harder mass, by th§ absorption of the watery part. There was a less quantity of fluid than is usual after eating more solid food. This is another striking demonstration of the laws that govern the action of the stomachic solvent. If water were permitted to remain in the stomach, it would render the soup too liquid to be acted on by the gastric juice. Experiment 37. March 15 — At 8 o'clock 30 minutes, a.m., break- fasted on fresh sausage^ light pancakes^ and a pint of coffee. At 9 o'clock 30 minutes, examined, and found the stomach full of fluids, mixed with the aliment, and a large portion of clear oil floated on the top, and presented itself at the perforation of the stomach. At 10 o'clock 30 mi- nutes, I took out a portion, — found the cakes and par- ticles of meat about half digested, with some oil, pure, bland, and limpid, rising upon the top, untouched by di- gestion. Placed it on the bath. . At 12 o'clock M., examined stomach, — found no ves- tige of his breakfast, not a particle of oil was to be seen, nothing but pure gastric juice could be extracted, of which I took out twelve drachms. That portion of his breakfast taken' out at 1 0 o'clock and 30 minutes, was at this time almost completely chy- mified, a few small particles of oil only remaining. The chymous mass of a milky colour, and thick gruel-like consistence. 154 very rapid digestion. Experiment 38. March 16. — At 8 o'clock 30 minutes, a.m., breakfast- ed on fresh meat and vegetable hash, bread, and a pint oi coffee. At 10 o'clock 30 minutes, examined, — found but very few particles of his breakfast in his stomach, — some oil, and a few flocculi of a brown colour, run out with a little thin fluid. At 1 1 o'clock, examined again, — found nothing but a little gastric juice. Breakfast was gone and the stomach clean. These experiments (37th and 38th), are continued proofs of the solvent action of the gastric juice. Experiment 39. At 2 o'clock p.m., same day, dined on recently salted lean beef, pork, potatoes, carrots, turnips, and bread. At 5 o'clock examined, — found the stomach clear of food, but containing a quantity of white frothy mucus, — villous coat inclined to dryness, and deeper pink colour. St M. complained of some headach, pain and distress at the pit of the stomach, dry skin, and thirst. Directed him to take four drachms of tincture of aloes and myrrh at bedtime. This operated two or three times next morning, and gave relief. The gastric juice, however, was not obtained in its usual quantity and quality, for twenty-four or thirty-six hours afterwards. Experiment 40. - March 18. At 9 o'clock a. m. he breakfasted on soused tripe smd pig^s feet, bread and coffee. DIGESTION OF GELATINE. 155 At 9 o'clock, 30 minutes, took out and examined a portion, — found it in a half digested condition, tripe, pig's feet, and bread, all reduced to a pulp, floating in a large proportion of fluids. Placed it on the bath. At 10 o'clock, examined stomach again, — tried to ex- tract another portion, — could find little or no chyme, — a very little gastric juice, with a tew small fibrous parti- cles of tripe, and some coffee -grounds. His breakfast appeared to have been digested, and had passed from the stomach in 07ie hour. The portion first taken out and placed on the bath, was also, at the end of one hour, reduced to nearly a complete chymous condition, a very few of the small par- ticles of tripe and coffee-grounds only left, as in the sto- mach. Remarks. — This is an example of astonishing rapidity of gastric solution ; and that, too, of articles generally regard- ed as rather hard of digestion. That there could be no mis- take, I infer from the fact, that a portion taken out of the stomach, thirty minutes after having been received, and submitted to the artificial mode, exhibited the same result. Experiment 41. At 1 o'clock p. M., same day, he ate eight ounces of calf's foot Jell?/, and nothing else. In twenty minutes, examined stomach, and took out a portion of its contents, consisting of gastric juice, com- 156 DIGESTION OF GELATINE. bined with the jelly, nearly all of it in a fluid form ; a few particles only of entire jelly, suspended in the fluids, with a few small yellowish-white coagulae floating near the surface, could be perceived. At 2 o'clock, examined again, extracted a little fluid, but found no appearance of jelly. Remarks. — The operation of gastric juice on gelatine, is very difficult to be detected. Unlike albumen, it is unsus- ceptible of coagulation ; and it is probable that the gastric juice acts upon it in its soft solid state. This was dis- posed of in a short period. It was, however, but a small quantity, and was much sooner digested than a full meal would have been. From various trials, I am disposed to think that gelatine, if not in too concrete a state, is a very digestible article of diet. During the examination at this time, St Martin swal- lowed part of a glass of water, and being situated in a strong light, favourable to an internal view, through the aperture, I distinctly saw the water pass into the cavity of the stomach, through the cardiac orifice, — a circum- stance, perhaps, never before witnessed in a living sub- ject. On taking repeated draughts of water while in this position, it would gush out at the aperture, the instant it passed through the cardia. Food, swallowed in this po- sition, could be distinctly seen to enter the stomach. Experiment 42. April 7. At 8 o'clock a.m., breakfasted on three hard boiled eggs, pancakes, and coffee. DIGESTION OF HARD BOILED EGGS, ETC. 1 57 At 8 o'clock, 30 mins. — examined stomach — found a heterogeneous mixture of the several articles eaten, slightly digested. At 8 o'clock, 45 mins. — examined again — found contents reduced in quantity, and changed in quality — about half digested. At 10 o'clock, 1 5 mins., no part of the breakfast remained in the stomach. Remarhs: — This, and the four following experiments, throw no additional light on the subject of digestion, ex- cept so far as relates to the period of chymification. This, it will be perceived, depends something upon the quantity eaten. The quality, however, is not to be overlooked. Experiment 43. At 11 o'clock, 15 mins. a.m. — the same day — he ate two roasted eggs and three ripe apples. In thirty minutes, examined stomach — found a he- terogeneous mixture, in an incipient stage of digestion. At 12 o'clock, 15 mins. m. — examined again — found the stomach clear ; no vestige of apples or eggs. Experiment 44. At 2 o'clock p. M. — same day — dined on roasted pig and vegetables. At 3 o'clock — examined, and found it about half chy- mified. At 4 o'clock, very little remained in the stomach. At 4 o'clock, 30 minutes, nothing remained but a very little gastric juice. 158 general conclusions. Experiment 45. April 8. At 2 o'clock p.m. he dined on wild goose. At 3 o'clock — stomach full of fluids, with a large por- tion of oil, floating on the surface ; the goose flesh in small shreds, and soft ; digesting rapidly. At 4 o'clock — contents of stomach two-thirds gone — that remaining, chymified. At 4 o'clock 30 mins., the stomach was empty and clean. Experiment 46. April 9. At 3 o'clock p. m. he dined on boiled, dried codfish, potatoes, parsneps, bread, and drawn butter. At 3 o'clock 30 mins. — examined, and took out a por- tion, about half digested ; the potatoes the least so of any part of the dinner. The fish was broken down into small filaments ; the bread and parsneps were not to be distin- guished. At 4 o'clock — examined another portion. Di- gestion had regularly advanced. Very few particles of fish remained entire. Some of the few potatoes were distinctly to be seen. At 4 o'clock, 30 mins — took out and examined another portion — all completely chymified. At 5 o'clock — stomach empty. Remarks. — The preceding experiments, I think, plainly demonstrate the solvent properties of the gastric juice. When aliment is submitted to it, out of the stomach, its operation is rather slower than when the process of diges- tion is assisted by the natural warmth and motions of that organ. One reason, probably is, the difficulty of maintain- ing a bath at the exact necessary temperature ; and ano- USES OF BILE AND PANCREATIC JUICE. 159 ther one may present itself, in the impossibility of per- fectly imitating the motions of the stomach. With all these disadvantages, however, chyme formed in this way presents the same uniform, sensible appearance, as that which is formed in the stomach by the natm'al process. That the cold gastric juice should not act at all, or but very imperfectly, on aliment, is no proof, in my opinion, that it does not possess solvent powers, even on the ad- mission that it was a debatable question. There are but few chemical combinations that do not require caloric to effect their operations, and none, perhaps, that are not facilitated by it. Some, and indeed many, of them re- quire an intense heat. I am under the impression, though I have never fairly tested the truth of it, that gastric juice would, in a sufficient length of time, act on aliment in a cold state. But I am not anxious to contend for any extraordinary or unnecessary powers of this fluid. Nor is it necessary to prove that it will act on cold substances, or in cold situations. It is perfectly manifest, that its operation is that of a chemical agent ; that it dissolves aliment out of the stomach, when the warmth and mo- tions of that organ are imitated ; and that it changes the various and heterogeneous articles, submitted to its ac- tion, to an uniform homogeneous semi-fluid, varying, however, slightly in colour and consistence, according to the aliment used. With a view to ascertain, if practicable, what effects were produced by the Bile and Pancreatic Juice, 160 EXPERIMENTS WITH BILE when added to Chyme, I instituted the following expe- riments. Not being able to procure human bile in a pure state, I obtained some ox-gall, and, for pancreatic juice, sub- stituted diluted muriatic acid (one scruple of acid to six ounces of water). I was induced to use this acid, from a resemblance observed between its taste and that of the pancreatic juice, and not being able to obtain any of that fluid at the time. These experiments are certainly very imperfect ; but such as they are, I submit them to the public. They may tend to pave the way to more perfect experiments on these fluids. Experiment 47. I divided the chyme, produced in experiment 24, Se- cond Series (Dec. 14. 1829), into two equal parts, about five drachms each. To one of which, I added one drachm of the ox-gall. Fine coagulae were immediately produced, of a slightly yellowish-green colour. To this I then added one drachm of dilute muriatic acid, which immediately produced a white balsamic mixture. This, after standing at rest a few minutes, separated into three distinct parts ; a clay-coloured sediment at the bottom, a whey-coloured fluid above, and a thin, oily, whitish pel- licle on the top. Experiment 48. To an ounce of the chyme, formed in Experiment 25 AND PANCREATIC JUICE. l6l (Dec. 16.) I added one drachm of the ox-gall, which im- mediately converted it into a milky fluid, very finely co- agulated. To this, I added one drachm of the diluted muriatic acid, which at first increased the coagulae, but immediately after threw down a brown precipitate. This, on the addition of more bile and acid, varied in colour, according to the different proportions put in, from a light clay colour, to a dark brown, tinged with green, without any change in the colour or consistence of the fluid above. On standing at rest, it separated into three distinct parts — a brown sediment at the bottom, a yellowish or whey -coloured fluid in the middle, and a thin, milky- white pellicle on the top. Experiment 49. Having procured some fresh gall from an ox recently slaughtered, I added twenty drops of it to four drachms of the chyme formed in Experiment 26 (Jan. 11. 1830). A turbid, yellowish- white fluid, or rather, very fine, cream-coloured coagulae, immediately formed ; which, after standing a few minutes, separated into bright, yel- low-coloured coagulae, subsiding towards the bottom, and a turbid, milk-coloured liquid above. By adding twenty drops more of the bile to this, the coagulae were increased, more collected together, and changed in colour, fi:om a yellow to a greenish hue. The addition of twenty drops more of bile (making, in the whole, one drachm), concentrated a deep grass - green, jelly-like deposition at the bottom of the vial. The fluid above became more milky in appearance ; and the o 162 EXPERIMENTS WITH BILE coagiilae and sediment became darker on the addition of bile. I now added twenty drops of the dilute muriatic acid to other four drachms of the same kind of chyme, with- out bile. This produced no change in the colour or con- sistence, but increased the saline, acid taste, peculiar to the gastric and pancreatic juices, when uncombined with chyme. By adding bile to this, the same effects and appear- ances were present as in the other similar experiments ; viz. a yellowish-brown sediment at the bottom, a whey-co- loured fluid in the middle, and a white pellicle on the top. To observe the different effects produced between a combination of bile and muriatic acid in clear water, and that of the chymous mass, I mixed equal quantities of the gall and dilute acid, one drachm each, with two ounces of water. This at first produced an effect, and exhibited an appearance, similar to that of their combination with chyme ; but gradually changed to a bluish, green-colour- ed, thin fluid, with a deep green, jelly-like deposition at the bottom, without any of the milky appearance of the chymous mixtures, or white pellicle on the top. Experiment 50. To four drachms of gastric juice, fresh from the sto- mach, 1 added forty drops of ox-gall, which produced a turbid, yellowish-green fluid, yielding no sediment. Forty drops dilute muriatic acid, added to other four drachms of the gastric juice, effected no change in its appearance. Equal parts of the bile and muriatic acid, mixed toge- AND PANCREATIC JUICE. 163 ther, produced a fluid of exactly the same colour as the first, but was less consistent. On mixing the two first together, and adding two drachms of chyme from the stomach, very fine coagul^ formed in a milky fluid, throwing down a brownish sedi- ment, from a whey-coloured liquor, with the same milky pellicle on the surface, as in the former experiments. To one ounce of chyme, formed in a vial, on the bath, I added two drachms of bile. A turbid, yellowish- white mixture formed, without sediment, or immediate separa- tion of any kind. To another ounce of the same chyme, I added two drachms of the dilute acid. No change in its appearance was perceptible. I then mixed them to- gether, and the appearance of both was changed. Whitish coagulae formed, and let fall a brown sediment, leaving an opaque, whey- coloured fluid above, with a pellicle or white flocculi on the surface. Experiment 51. Bile added to the third portion of the chyme, taken from the stomach one hour and ten minutes after a break- fast of venison steak, &c. Experiment 29 (March 6. 1 831), changed it from a brownish, homogeneous paste, to a milky fluid, with small white flocculi, floating about, or adhering to the sides of the vial ; and a light brown sediment settled to the bottom. The usual proportion of dilute muriatic acid, added to this, produced no very essential change in its appearance, causing only a little more deposition of sediment, and slightly increasing the milky colour. 164 experiments with bile Experiment 52. Bile added to the chyme formed from the eggs, digest- ed out of the stomach, Experiment 30 (March 7. 1831) produced a rich, milky fluid, with a small quantity of fine light- coloured sediment, falling to the bottom. The dilute acid, added to this, produced fine coagulae, and formed a milk-white whey, or fluid, firom which, more of the fight- coloured sediment was precipitated. Experiment 53. More minutely to observe the respective changes by the addition of bile and muriatic acid, in the several par- cels of chyme formed in Experiment 31 (March 7. 1831), and to note their difference, I put equal quantities of each into glasses, and added a portion of hog's gall. In the first (that taken from the stomach at 10 o'clock, one hour after having eaten), fine bright orange- coloured coagulae were immediately formed, equally diffused through a fluid of the same colour, exhibiting no perceptible se- diment on standing at rest, but held the coagulae, uni- formly suspended throughout the fluid. The dilute acid, added to this, occasioned a copious sediment to fall to the bottom, and with it, all the colour of the mixture, leaving a transparent, semi-gelatinous-like fluid above, in the proportion of about three-fifths of the whole ; upon the surface of which floated a thin, white pellicle. The second portion (that produced on the bath), un- der the same treatment, exhibited nearly the same ap- pearance, with the exception of the colour, which was a AND PANCREATIC JUICE. 165 shade or two lighter. The sediment was not quite so compact ; the fluid less gelatinous ; and there was less of the white pellicle on the surface. The third portion, treated like the other two, diflPered about as much from the second, as this did from the first. They all exhibited the same general appearance. The fourth, or aqueous portion, under the same treat- ment, exhibited a wide difference. The same propor- tion of bile added to this, produced a similar coloured fluid, at first, with very little coarse coagulae — not so uniformly diffused through the liquid, but inclining more to precipitation. On adding the acid, it let fall a very small quantity of yellowish-green sediment, leaving a thin, semi-transparent fluid, in more than quadruple the proportion of the other three. Experiment 54. Bile and dilute muriatic acid, added to a portion of the bread and milk chyme, formed in Experiment 35 (March 14.), produced their usual coagulation and pre- cipitation, but of a lighter yellow ; the sediment form- ing about one-fourth of the mass. The small, white par- ticles, forming the pellicle on the top, were in greater proportion than in some of the other experiments, espe- cially those on lean meats. The fluid part was in greater proportion to the sediment, and of a whey colour and con- sistence. To another equal quantity of this same kind of chyme, I added bile, as in the other, and instead of muriatic acid, I used pancreatic Juicey fresh from a recently slaugh- 166 EXPERIMENTS WITH BILE AND PANCREATIC JUICE. tered ox. An appearance exactly similar to that pro- duced by the acid, was exhibited, except that the preci- pitate was more slowly thrown down, and in larger pro- portion ; and the white pellicle on the surface was less. The fluid and sediment were a shade lighter, and in more equal proportions. Experiment 55. Pancreatic juice, combined with the chyme of roast beef, formed both in and out of the stomach, increased its thin paste-like consistence, and gave it more of a cream colour. Bile added to this produced fine coagulae, suspended from the top to the bottom without depositing any distinct sediment. Diluted muriatic acid darkened the whitish colour a shade or two, threw down a more copious sediment, and increased the white pellicle on the top. Experiment 56. Bile and pancreatic juice added to the fresh meat and vegetable soup chyme (Experiment 36, March 14. 1832) produced loose cream-coloured coagulae, which, on stand- ing, separated into three, about equal proportions ; a coarse brownish sediment, a semi-transparent whey- coloured fluid, and a thick white pellicle at the top. ( 167 ) THIRD SERIES. Washington, D. C. 1832. Experiment 1. Dec. 4. — At 2 o'clock 30 minutes, p. m weather cloudy, damp, and snowing. Thermometer 35° ; ^^'ind N. W. and brisk ; the temperature under the tongue was 99° ; in the stomach 101°. Dined, at 3 o'clock 30 mi- nutes, on beefsoKp, meat, and bread. 4 o'clock 15 mi- nutes,— took out a portion ; particles of beef slightly ma- cerated, and partially digested. 5 o'clock 15 minutes, took out another portion ; digestion more advanced ; meat reduced to a pufp ; particles of bread and oil float- ing on the top ; temperature of stomach 100°. 6 o'clock 45 minutes, digestion not completed ; contents consider- ably diminished. 7 o'clock 45 minutes, stomach empty ; chyme all passed out. Experiment 2. Dec. 5 At 7 o'clock a. m — temperature of the sto- mach 100°, of the atmosphere 30°. At 1 o'clock p. M. — temperature of stomach 100°, atmosphere 40°, — he ate eleven raw oysters and three dry crackers, and I suspended one raiv oyster into the stomach, through the aperture, by a string. 1 o'clock 168 EXPERIMENTS ON DIGESTION. 30 minutes, examined ; stomach full of fluids ; digestion not much advanced.^ The oyster on the string appeared entire, though perhaps slightly affected on the surface. 2 o'clock — examined, and took out oyster ; about one- third digested, but retained its shape. 2 o'clock, 30 mi- nutes, oyster gone from the string, except a small piece of the heart. Temperature of the stomach 101|°. Fluids less considerable. 4 o clock, 15 minutes, stomach empty. Experiment 3. At 3 o'clock, 45 minutes, p. m., same day, he dined on roast turkey, potatoes, and bread. 4 o'clock, 30 minutes, examined, and took out a portion. Turkey nearly all dis- solved ; vegetables half reduced. 5 o'clock, 1 5 minutes, took out another portion, almost completely chymified. 5 o'clock, 45 minutes, examined again ; stomach nearly empty. 6 o'clock, some chyme yet remaining. 6 o'clock, 15 minutes, stomach empty. ^ Experiment 4. Dec. 6 At 8 o'clock, 30 minutes, a. m. he break- fasted on bread and butter, and one pint o^ coffee. 9 o'clock, 45 minutes, examined ; stomach full of fluids. 1 0 o'clock, 30 minutes, examined, and took out a portion resembling thin gruel in colour and consistence, with the oil of the butter floating on the top, a few small particles of the bread and some mucus falling to the bottom ; about two- thirds digested. It had a sharp acid taste. Tempera- ture of the stomach 100°, atmosphere 38°. 11 o'clock, 30 minutes, stomach empty. experiments on digestion. 169 Experiment 5. At 4 o'clock, 30 minutes, p. Mc, same day, he dined on sausage and bread; full meal. 5 o'clock, 30 minutes, stomach full of fluids ; digestion but very little advanced. 6 o'clock, 30 minutes, digestion considerably advanced ; few distinct particles of sausage and bread to be seen en- tire. 7 o'clock, 30 minutes, stomach empty. Experiment 6. Dec. 7- — At 8 o'clock a. m. — examined stomach, and took out, with considerable difficulty, an ounce only of gastric juice, and that not very pure. Some yellow bile came mixed with the latter portions. Temperature of the stomach 99°? atmosphere 28°. He breakfasted, at 9 o'clock, on corn and wheat bread, butter, and coffee. At 10 o'clock, 45 minutes, examined and took out a portion ; food partly digested ; few small particles to be seen. Stomach full of fluids, with a thin pellicle of oil on the top. Temperature of the stomach 100°. At 12 o'clock A. m., stomach full of fluids ; digestion not com- plete ; particles of bread floating about in a pulpous state ; oil floating on the surface. At 12 o'clock, 30 minutes, A. m., examined ; contents of stomach half diminished ; distinct particles of oil on the surface. At 12 o'clock, 45 minutes — entire particles of bread yet to be seen ; quantity of fluid diminishing. At 1 o'clock p. m., dis- tinct particles of bread still floating ; fluid less. At 1 o'clock, 15 minutes, stomach empty. Remarks. — Some indications of gastric derangement 170 DIGESTION RETARDED BY STOMACHIC DISEASE. this morning; small aphthous patches on the mucous membrane ; juice acrid and sharp, with bile mixed with it. Experiment 7. At 3 o'clock, 30 minutes, p. m., same day, he dined on roasted mutton, bread, and potatoes. 4 o'clock, 45 mi- nutes, examined ; stomach full ; digestion advancing. 5 o'clock, 45 minutes, contents of stomach three quarters reduced in quantity, and almost completely chymified. 6 o'clock, 30 minutes, stomach nearly empty ; a little pulp of the bread only to be seen, floating in a little milky fluid. 7 o'clock, stomach empty. Experiment 8. Dec, 8 At 5 o'clock, 30 minutes, a. m. — temperature of stomach 99°» 9 o'clock, finished breakfasting on fried sausage, dry toast, and a pint of coffee, 10 o'clock, 30 minutes, stomach full of fluids ; villous coat red and irri- table, inclining to dryness ; a thin whitish coat on the tongue, and a similar appearance on the protruded por- tion of the stomach. 1 1 o'clock, 45 minutes, stomach full ; oil floating on the top, and rancid. Temperature of stomach 99° ; atmosphere 46°. Weather damp and cloudy. Remarks. — This, and the 6th Experiment, shew, tha when there are indicationsof disease on the coats of the sto- mach and on the tongue, digestion is consequently pro- tracted; and, also, that oil is particularly hard of digestion. Experiment 9. At 9 o'clock, a. m., same day, the vial containing the DIGESTION RETARDED BY STOMACHIC DISEASE. 171 bread and butter aliment, taken from the stomach on the 5th inst. (Experiment 4), at half-past 10 o'clock, "a. m., was placed on the bath for four hom's, in the usual tem- perature, between 95° and 100°. Digestion commenced, and advanced regularly, partially reducing the oil to a milky fluid. December 9 At 1 1 o'clock, a. m., added one ounce of gastric juice, and continued it on the bath for eight hours, when the oil became more, but not completely di- gested J particles of the limpid oil being still perceptible Remarks. — This affords an example of the re-com- mencement of digestion, after the operation had ceased, by the addition of a fresh supply of gastric juice. Experiment 10. At 2 o'clock, 45 minutes, p. m., same day (Dec. 8 j, I suspended a roasted oyster, weighing, when raw, four drachms, into the stomach, and he ate twelve of the same kind, each weighing about the same. At 4 o'clock, 30 minutes — examined — oyster remain- ing on the string, not half digested — fluid in the stomach rancid. Complained of headach, lassitude, dull pains in the left side, and across the breast — tongue furred, with a thin yellowish coat, and inclined to dryness — eyes heavy, and countenance sallow. The villous membrane of the protruded portions of the stomach, very much resembled the appearance of the tongue, with small aphthous patches; in several places quite irritable and tender. I suspended observations, and dropped into the aper- i?^ DIGESTION AS AFFECTED BY ture, at night, six grains blue pill, and four aloetic pills.^ common size, and sprinkled on the exposed surface of the stomach, five or six grains of calomel. Medicine operated early the next morning ; relieved the symptoms of indis- position ; 'changed the appearance of the stomach and tongue ; and removed the aphthae. On the 9th, he felt quite well ; and the coats of the stomach looked healthy again. Experiment 11. December 13. — At 7 o'clock a. m temperature 100° — villous membrane perfectly healthy, of a pale pink colour, and uniform — mucous coat smooth and even. Extracted two ounces of gastric juice. It distilled more freely than common. More could have been obtained. I had never before seen the pure juice flow so freely. He felt in per- fect health ; had taken neither food nor drinks since 9 o'clock last evening. At 9 o'clock, breakfasted on broiled breast of mutton, bread, butter, in usual quantity, and a pint of coffee, and kept exercising. Digested in three hours and a half, stomach empty and clean. Experiment 12. At 2 o'clock p. M., same day — stomach empty — coats clean — ^he dined on three soft boiled eggs and bread, and drank half a pint of water. 3 o'clock — digestion advan- cing. 4 o'clock. Contents nearly gone from the stomach. Yolk of eggs still visible, with a few particles of oil. 5 o'clock. Very little chyme in the stomach. 5 o'clock, 1 5 DISORDER OF STOMACH. 173 minutes. Some still remaining. Complains of slight headach. Pulse full and crowded. Contents of the sto- mach acrid. Countenance rather sallow. Eyes languid. Tongue a little coated with a thin yellowish fur. His bowels have not been moved since yesterday morning at 10 o'clock; then inclined to costiveness. N. B. — After taking breakfast, he exercised moderately. About 12 o'clock a.m., he walked about two miles, very quick. After his return to his lodgings, he threw off his coat, and went into the open air again. Soon after which, he began to feel the pain in his head, &c. Experiment 13. December 1 4. — At 7 o'clock a. m. Stomach deeper colour than ordinary, and inclined to dryness. Some small aphthous patches, and spots of darker colour. Mucous coat not uniform and even ; some places thicker, a little elevated, and rolling up like thin membrane, leaving a spot beneath red and irritable. Very little juice could be extracted. I obtained a small quantity of fluid, mixed with yellow bile ; it did not yield the peculiar acid taste of the gastric juice. Temperature of the stomach, 100°. St Martin did not feel his usual appetite. At 9 o'clock, he breakfasted on the same kind of diet as yesterday ; had less appetite, and was labouring un- der some gastric derangement. He continued quiet, most of the time in a recumbent position. 10 o'clock. Sto- mach full. Globules of oil floating about. Appearance of villous membrane about the same ; no perceptible change. 11 o'clock. Stomach still full. Appearances 174 EXPERIMENTS ON DIGESTION similar to those in last examination. 12 o'clock a.m. Contents half diminished. Particles of bread, and coat of oil on the surface. 1 o'clock p. m. Some fluid still in the stomach, and a larger proportion of oil than at last examination. Taste of the contents more sharp and ran- cid ; fast leaving the stomach. At this time. I observed several small sharp-pointed white pustules, or pimples, here and there dispersed over the exposed portion of the inner coat. 1 o'clock, 30 minutes. Stomach clear and clean. Experiment 14. At 2 o'clock p. m., same day, he dined on three soft boiled eggs, bread, and butter, and half a pint of luater (same as yesterday, 2 o'clock). Digested in three hours. Experiment 15. December 15. At 8 o'clock a.m. I examined stomach. Temperature 100°. Appearance of coats more natural and healthy than yesterday niCrning ; less of those small white pointed pimples, and aphthous spots. Very little gastric juice could be obtained ; not more than one ounce, and that mixed with an unusual quantity of mucus, not so clear as common. Complained, as he frequently does during this operation, of a sense of sinking, and vertigo after extracting this quantity. This feeling, however subsided in a few minutes after rising. At 8 o'clock, 30 minutes, he breakfasted on beef-steak bread, and coffee. At the same time, he thoroughly mas- ticated four drachms of the steak, which I put into the OUT OF THE STOMACH. 175 gastric juice just before taken from the stomach. To another similar quantity of gastric juice, I put the same quantity of the steak, unmasticated, and in one entire piece. I placed them both on the bath at 1 00°, and at the same time, I put the same quantity of steak into one ounce of simple water, and treated it with the others on the bath. At 11 o'clock I examined the stomach, and found his breakfast nearly digested, and more than half gone from the stomach. I took out an ounce of what remained, which was almost completely chymified, a few particles of the bread, in a soft pultaceous condition, only remain- ing. Compared this with the three parcels on the bath. It very nearly resembled the masticated meat in the gas- tric juice, but was more digested, and thinner, and con- tained particles of oil (melted butter) and bread, which were not in the masticated food in the vial. The unmas- ticated meat differed considerably. It was not so thick and gelatinous-like ; was of a darker colour ; and the piece of meat retained its shape, and was not much dimi- nished in size, the surface only a little wasted, softened, and covered with a cineritious coat. The contents of the vial of masticated meat and water suffered very little or no change since put in ; no more than had been effected simply by mastication. Continued them all on the bath. The contents of the vials, continued on the bath for twenty-four hours, exhibited the following changes. The portion taken from the stomach at 1 1 o'clock, remained nearly the same as when extracted, perhaps more com- pletely chymified. That which was masticated and put into the gastric juice, was reduced to a thick pultaceous 176 VARIOUS EXPERIMENTS ON DIGESTION. semi- fluid mass, but retaining some distinct fibres of the meat, which, after standing a while, subsided to the bot- tom of a yellowish whey- coloured fluid. These remain- ing particles of aliment, I conceived to have been left for want of a sufficient quantity of gastric juice, the quan- tity at first being too small to dissolve the whole of the meat put in. That portion in the vial of water had un- dergone no other change than that of incipient putrefac- tion, which was very evident. The unmasticated piece of meat had undergone an evident process of digestion. It was about half diminished, and the texture of the re- maining part loose and soft. The containing fluid had become of a greyish-brown colour, opaque, with a fine brown sediment settling to the bottom, similar to that of the masticated meat in the gastric juice. The gastric juice, containing the unmasticated meat, when taken from the stomach some sixty or seventy hours before, was not so pure as common, was mixed with yellow bile, and was in too small proportion to the meat. The colour and flavour of the other two portions were very similar, except that the one with the masticated meat was more sharp and acrid. Remarks, — This experiment shews the necessity of mas- tication ; and also demonstrates, that simple maceration, at the natural temperature, will not effect digestion. Experiment 16. A dinner of pork-steak and breads taken at 1 o'clock p. M-, same day, digested in three hours forty-fiye minutes. various experiments on digestion. i ;7 Experiment 17. December 1 6. — At 9 o'clock a. m., he breakfasted on cold pork-steak^ breads and one pint coffee. Digestion completed in three hours. Two hours after having eaten, a pellicle of oil was found floating on the top of the gas- tric contents. On examining the stomach, an hour after the chyme had passed out, several red spots and patches, abraded of the mucous coat, tender and irritable, appeared spread over the inner surface. The tongue, too, had upon it a thin whitish fur. Yet his appetite was rather craving. At 2 o'clock, 30 minutes p. m., he ate a full dinner oicold roasted pork (fresh), breads and a piece of raic radish. Digestion completed in seven hours. Experiment 18. December 17 At 8 o'clock, 30 minutes, a.m., I put two dvdichxa^ fresh fried sausage in a fine muslin bag, and suspended it into the stomach. He immediately after breakfasted on the same kind of sausage^ and a small piece of broiled mutton^ wheat breads and a pint of coffee. 1 1 o'clock, 30 minutes, stomach half empty, contents of bag about half diminished. 2 o'clock p.m., stomach empty and clean,^ — contents of bag all gone, except fifteen grains, consisting of small pieces of cartilaginous and membran- ous fibres, and the spice of the sausage, which last weighed six grains, leaving only nine grains of the aliment put in. In consequence of being called out, I delayed the last examination longer than was necessary. 178 various experiments on digestion. Experiment 19. December 18. At 8 o'clock, 30 minutes, a.m., I sus- pended two drachms masticated, fried sausage^ confined in a muslin bag, into the stomach, and he breakfasted on the same kind of food, with bread and coffee, 11 o'clock, 30 minutes, stomach half empty — contents of bag about half gone. 1 o'clock p. m., stomach nearly empty — very little left in the bag. 1 o'clock, 30 minutes, stomach clear, except the bag, which contained a little of the sausage ; took this out, and it weighed one drachm, spice and all, of which there was less than yesterday. The bag, when drawn out, came from near the pylorus, and was covered with a coat of mucous and yellow bile. The ^contents of the stomach have been unusually acrid since yesterday morning, and he complains of unusual smart- ing and irritation at the edges of the aperture ; counte- nance sallow ; tongue covered with a thin yellowish coat, and several deep red patches on the inner coat of the stomach ; does not feel his usual appetite. 9 o'clock — dropped into the aperture twelve grains blue pill, and five cathartic pills — operated early the next morning, removed the symptoms, and restored his healthy sensa- tions and functions. Experiment 20. December 19 — At 8 o'clock, 45 minutes, a. m., I sus- pended three drachms broiled bass, in a muslin bag, into the stomach, and he breakfasted on the same kind offish, with, bread, a small piece of sausage, and a pint of coffee. VARIOUS EXPERIMENTS ON DIGESTION. 179 2 o'clock P. M. — complains of smarting at the aperture — I took out the bag — remaining contents weighed two drachms, having lost one drachm only in five hours and a quarter. Coats of the stomach did not appear healthy -—deeper red than natural, with patches of still deeper colour spread over the protruded portion. Mucous covering abraded in places and rolled up, resembling shreds of epidermis, torn from a blistered surface. Remarks. — These three last experiments are examples of the solvent or chemical action of the gastric juice. It penetrated the muslin bags, dissolved the food, and allowed the chyme to strain out. They also indicate, that irri- tating substances (as, for instance, the muslin bags in these experiments) produce a diseased state of the sto- mach. Experiment 21. December 20 At 8 o'clock, 30 minutes, a.m., — Coats of stomach appear healthy — considerable fluid plainly to be seen. It ran out of the aperture on turn- ing him down ; was transparent, and contained flocculi of mucus. Breakfasted on broiled bass, toasted bread, and coffee. Digested in five and a half hours. Experiment 22. At 2 o'clock p. M. he dined on boiled chicken and toheat- bread. Digested in four and a half hours. 180 various experiments on digestion. Experiment 23. December 21. — At 8 o'clock, 30 minutes, a.m. — sto- mach not perfectly healthy — several small deep-red patches on the exposed surface. Extracted four drachms gastric juice, tinged with yellow bile. Masticated one and a half scruples of the thigh of a boiled chicken, and half a scruple of bread ; put them into tliis gastric juice, and placed the vial in the axilla. Into the same quantity of pure water, warmed to 70°, I put the same quantity and kind of aliment, and placed them in the same situation. He breakfasted at the same time on the same kind of diet. 1 o'clock p. M. — stomach empty. At 2 o'clock he dined on same kind of food. 6 o'clock, 30 minutes — stomach empty. The masticated portion put into the vial of gastric juice, placed on the bath, and frequently agitated, digested re- gularly and uniformly until about 2 o'clock, p.m., when the particles were all dissolved, except a few fibres. That in the vial of water, kept in the same situation, had not changed its appearance from the time it was put in. On separating the remaining particles of food, in the gastric juice, at evening, filtering on thin muslin, and drying with paper, it weighed fifteen grains, and left four drachms and a fraction, of an opaque, milky-coloured fluid. That in the water, taken out at the same time, weighed forty grains, and left four drachms of a turbid fluid, like water, with flour stirred in it, and had a maw- kish, insipid taste and smell. The first had the acid smell and taste peculiar to the gastric contents. various experiments on digestion. 181 Experiment 24. I>ec. 22. At 8 o'clock a.m. — examined stomach — tem- perature 100°. Extracted about four drachms gastric juice, pure but not free. At 8 o'clock, 30 mins., he breakfasted on breads, cheese^ and coffee. 9 o'clock — stomach full of fluids — temperature 100°. 11 o'clock — stomach full, with the cheese in a fluid form, floating on the surface ; bread reduced to a pulp — temperature 100°. 12 o'clock M. — ^food still in the stomach ; but consider- ably diminished. 1 o'clock, 30 mins., p.m. — some of the cheese yet remaining — stomach nearly empty. 2 o'clock — stomach empty. The coats of the stomach have not appeared in their usual healthy condition for several days past — the colour darker — mucous coat unequal — some patches of a pur- plish colour, with aphthous edges — surface inclined to be dry — very little secretion of gastric juice — digestion slower and less perfect than usual — bowels inactive, nothing having passed them for sixty hours. Remarks. — It would seem from this experiment, that cheese was difficult of digestion. In addition to its closeness of texture, it generally contains a large proportion of oil. Experiment 25. Dec. 23. At 6 o'clock a.m. — temperature of stomach, 100° — ^pulse ^6 a minute. 9 o'clock — temperature of stomach 100° — pulse 75. Villous membrane incHned to dryness, and of a darker than natural colour ; papillae 182 CURIOUS STATE OF STOMACH. small and sharp ; mucous covering scarcely perceptible ; bowels costive ; tongue coated with a yellowish fur, and its edges pale. I poured in, at the aperture, one ounce 01. Ricini, and sprinkled over the surface of the protru- ded coats five or six grains of calomel. He ate a light breakfast of corn-bread and crackers, and drank a pint of coffee immediately after. At 2 o'clock p. M. — stomach empty — coats look heal- thier. Medicine not having moved the bowels, I put in, at the aperture, twelve additional grains of calomel, per se. At 5 o'clock, the stomach was in commotion — indi- cations of the cathartic operation of the calomel ; slight nausea ; stomach full of a white frothy fluid, running out at the aperture, like fermenting beer from a bottle ; slight pain and motion in the bowels ; and increased secretion of saliva. No motion from the bowels. Temperature of stomach 101°. Pulse 80 beats in a minute. At 8 o'clock, calomel had operated twice, copiously, commencing at 7. Temperature^of stomach, 100°. Pulse 62, soft and mild. Experiment 26. Dec. 25. 'At 8 o'clock a.m. — weather partially cloudy — atmosphere dry, and smoky — wind E. and light — Th. 31°. Temperature of the stomach, 100° and a fraction. Pulse 55 in a recumbent position ; Q6, sitting erect. A few small red spots on the mucous surface. The gastric secretions appear as healthy as usual. At 9 o'clock, he breakfasted on boiled, salted fat pork, corn-bread, and coffee. 10 o'clock, the stomach at the INCREASE OF HEAT IN STOMACH. 183 same temperature as at 8 o'clock. Pulse 65 in a recum- bent and 75 in an erect position. Gastric cavity full of a heterogeneous mixture. At 11 o'clock, 30 mins. — just returned from walking moderately, about an hour, a dis- tance of two and a half miles ; not to produce free per- spiration, but gentle diaphoresis. Weather clear, calm, and dry. Th. 50°. Temperature of the stomach 101°. Pulse 72, in a recumbent position ; 82, sitting erect, and regular. Contents of stomach half reduced, and nearly homogeneous. At 12 o'clock, 30 mins., m. — tempera- ture of stomach 100|°. Pulse 62, recumbent; 72 erect. Contents nearly gone. At 1 o'clock, 30 mins., p.m., sto- mach empty. At 9 o'clock, — weather cloudy — atmosphere dry — no wind — Th. 42° — the temperature of the stomach was 99 J °. He drank half a pint of water fifteen or twenty minutes before examination. Pulse 62, recumbent ; 72, erect. This is an example of the increase of the temperature of the stomach on exercise. See also, subsequent expe- riments.. Experiment 27. Dec, 26. At 6 o'clock a.m. — weather cloudy — atmos- phere damp — wind N.E. and light — Th. 38° — tempera- ture of the stomach 99i°. Pulse 55, recumbent; 65 erect. Respirations, in a recumbent position, 1 5, and in a sitting posture, 18a minute. At 8 o'clock, he return- ed from a walk of two miles, but not to produce perspira- 184 EXPERIMENTS ON DIGESTION. tion. Weather damp, and raining lightly. Th. 36°. Temperature of the stomach, 101°. Pulse 65, recum- bent ; 85, erect. Feelings of impatience here evidently accelerated his pulse, in the erect position. He was vexed at being detained a few minutes from his breakfast. At 5 o'clock p. M. — weather rainy — wind N. E. — Th. 41° — I examined the stomach. Temperature, 99 J' Pulse, 60 recumbent ; 70, erect. At 8 o'clock, the tem- perature of the stomach, 101*. Pulse, 50 recumbent; 60, erect. Respirations, 15a minute. His diet through the day had been confined princi- pally to farinaceous substances, wheat-bread and crackers, in moderate quantities. Experiment 28. Dec. 27. At 6 o'clock a.m. — weather unpleasant — at- mosphere damp — wind E. — Th. 38°. Temperature of stomach, 99|° — surface clean and healthy — no dark red, or aphthous patches, nor white, with elevated points — mu- cous coat uniform and even, of the natural colour — no excoriation or smarting at the edges of the aperture. I extracted one ounce of gastric juice, slightly tinged with yellow bile. This I conceive to have been entirely ac- cidental ; and occasioned by the regurgitation of the bile through the pylorus, as he turned upon his back, from right to left, to favour the exit of the gastric juice. The same thing has happened several times before. At 9 o'clock, he breakfasted on three ounces broiled breast of mutton, four ounces of wheat and corn bread, very thoroughly masticated, and a pint oi coffee. At the EXPERIMENTS ON DIGESTION. .185 same time, I put two drachms of same kind of food, equally well masticated, into the ounce of gastric juice taken from the stomach at 6 o'clock, and the same quan- tity of same kind of food, masticated in the same manner, into an ounce of simple water, placed them both together first in the axilla and afterwards on the bath, between 96° and 100°. At 12 o'clock M., stomach nearly empty. Was just able to get out one ounce for comparison, almost com- pletely dissolved ; a few particles of bread only visible. Temperature 100°. At 12 o'clock, 30 minutes, no dis- tinct particles of food to be seen. All chymified and passed from the stomach. Nothing but a little frothy mucus remaining in the stomach. Coats clean ; colour pale pink. Temperature 100°. At 2 o'clock p.m. he dined on the same quantity and kind of food that he had taken for his breakfast (broiled mutton and bread). Drank nothing since morning. Temperature of stomach 100° ; thermometer 62° ; wind S. ; weather fair since 12 o'clock. 2 o'clock, 30 minutes, stomach as full of fluids as when he drank a pint immediately after eating. No percepti- ble difference in appearance. 6 o'clock, stomach empty and clean. 9 o'clock, temperature of the stomach 100°. Weather the same as at 2 o'clock. The changes effected in the contents of the two vials, mentioned above, and kept in the axilla till 9 o'clock p. m. were as follows : — In that containing the gastric juice, the food was about half dissolved and loosely suspended towards the bottom of a reddish -grey coloured fluid. That in the water exhibited no other appearance of di- 186 DIGESTION AND MACERATION COMPARED. gestion than what was effected by mastication, when first put in. The masticated food had subsided to the bottom of a transparent watery fluid, as clear as when first put in. At 8 o'clock A. M. of the 28th, I added the two drachms of gastric juice taken from the stomach at that time, to the vial containing the gastric juice, and the same quan- tity of water to the watery mixture, and placed them in the axilla again. At 6 o'clock p.m. examined vials — di- gestion had recommenced, and advanced in the gastric juice in proportion to the quantity added. The sediment had become more dissolved, and the fluid part increased. This sediment taken out, filtered through muslin, and pressed as dry as when4)ut in, weighed forty -five grains only, having completely dissolved one drachm and fifteen grains, and produced a gruel-like milky-coloured fluid. That in the water remained unchanged, and when taken out and pressed dry through a piece of mushn, like the other, weighed one drachm and thirty-five grains. This reduction, I suppose, was the effects of mastication and maceration in the water for thirty-six hours. These two parcels, kept tight corked, in a temperature between 50<^ and 70°, remained free from any fcEtor for forty-five days. The gastric portion, at the end of this time, emitted a caseous flavour, and the aqueous portion smelt musty and sour. Remarks. — This is a comparison between solution by the gastric juice and maceration in water. These results are interesting, not only as establishing physiological principles on certain data, but they have an important practical ap- DIGESTION OF A LARGE MEAL. 187 plication. They have, consequently, been frequently repeated. The fact, that the stomach contains aquantity of fluid, soon after the ingestion of dry food, which was alluded to in the preliminary essay, is here perfectly demon- strated. Experiment 29- December 28 At 8 o'clock a. m. weather clear ; at- mosphere dry ; wind N. ; thermometer 34°. Tempera- ture of stomach, 100°. Coats clean and healthy. Gas- tric juice scarce ; extracted two drachms only, and that with considerable difficulty. At 9 o'clock a. M. he breakfasted on same kind of food as yesterday, in usual manner, slightly masticated, and swallowed fast, without regard to quantity. 1 o'clock p. M. a small portion still in the stomach — nearly dissolved. 1 o'clock, 30 minutes, stomach empty. Experiment 30. December 29. — At 9 o'clock a.m. weather clear and dry ; wind N. W. and light ; thermometer 34° ; tempe- rature of stomach 100°; coats clean and healthy; he breakfasted on fat pork, dry toasty and coffee — full meal. 1 o'clock p. m. stomach half full of lardaceous fluid — no particle of any thing else but gastric fluids to be seen. Temperature 100°. 2 o'clock, 30 minutes, stomach not empty. 3 o'clock, stomach empty and clean. Remarks, — The protracted period of complete chymifi- 188 EXPERIMENTS ON DIGESTION. cation in this meal, I conceive to have been principally ow- ing to the unusual quantity of food taken being dispropor- tioned lo the gastric secretions, and more than vras requir- ed to replenish the natural waste of the system. The quality of the food had undoubtedly some effect. Experiment 31. December 30 — At 8 o'clock a. m. weather clear and dry ; wind N. W. and Hght ; thermometer 26° -, stomach ■ clean and healthy; temperature 100°. Gastric juice pure, and distills more fi-eely than common. Extracted one ounce without any difficulty. At 9 o^clock he breakfasted on two and a half ounces of boiled recently salted fat pork, three ounces of wheat- bread, masticated in usual manner, and one pint o? coffee. At the same time, I took two parcels, equal quantities, of the same kind of food (pork and bread), half a drachm of each kind, both masticated in same manner, put one of them into the ounce of gastric juice taken from the stomach before eating, and the other into the same quan- tity of simple water, of the temperature of the gastric juice, and placed them in the axilla. At 1 1 o'clock, I took out of the stomach one and a half ounces of its contents, put them into a vial, and placed it in the axilla with the other two. The difference be- tween this taken out of the stomach, and that in the gas- tric juice, was quite perceptible. The particles of ali- ment contained in the last, appeared more nearly dis- solved, very few remaining distinct. That taken from the stomach contained a larger proportion of the entire STOMACH ACTED UPON BY INTOXICATION. 189 food and floating oil. The colour of the middle portions, as well as the smell and taste, were very similar. That from the stomach was rather more rancid and sharp than that in the gastric juice in the vial. Both possessed the peculiar gastric acid flavour. At 1 o'clock, 30 minutes, the stomach was empty and clean, and probably was so at 1 o'clock ; but owing to ac- cident, I did not examine at that time. He became intoxi- cated in the afternoon, and interrupted the experiments. On the 2d oi January 1833, I added half an ounce of fresh gastric juice to the parcel of chyme taken from the stomach at 11 o'clock, in the above experiment, which, at this time, contained a large proportion of undigested lard- aceous matter, floating on the surface. Put the vial in the axilla. On the 3d, I added three drachms more of fresh gas- tric juice to the above. On the 6th, I added three drachms gastric juice to the above, and placed it on the bath. On the addition of each of these portions of gastric juice, chymification recommenced, and the lardaceous portion of the aliment continued to be reduced for seve- ral hours, till the solvent power became expended, when its action would cease. Experiment 32. December 31. — At 7 o'clock a.m. weather cloudy ; at- mosphere damp and chilly ; wind S. ; thermometer 30° ; temperature of the stomach 100|° ; colour darker red than natural, and arid. Mucous coat abraded in spots, 190 EXPERIMENTS ON DIGESTION. and rolled in small shreds ; more irritable than usual. At 8 o'clock, 30 minutes, breakfasted on same quantity and kind of food as yesterday (pork, bread, &c.). At 11 o'clock, took out one and a half ounces contents fi'om the stomach, in appearance half digested. 12 o'clock m. took out another portion more completely dissolved. Stomach nearly empty. 1 o'clock, stomach empty. At I o'clock, 30 minutes, he dined on salted boiled beefi po- tatoes, parsneps, and bread, full meal, without regard to quantity or mastication. 4 o'clock, 30 minutes, stomach perfectly empty. The one and a half ounces taken from the stomach at II o'clock A.M. very nearly resembled the contents of the vial of gastric juice and masticated food of the 30th (yesterday) in almost every particular. That' taken out at 12 o'clock M. had more of the lardaceous and less of the distinct fibrous particles of aliment. The diseased appearance of the stomach at this exa- mination, was probably the eflPect of intoxication the day before. Experiment 33. January 1. 1833 At 8 o'clock a.m. weather dark and rainy ; wind S. ; thermometer 50° ; temperature of stomach 100°, healthy and clean. Extracted half an ounce of gastric juice. At 9 o'clock, I took two scru- ples salted lean beef (boiled), chopped very fine with a knife, put one scruple into the half ounce of gastric juice, and the other scruple into half an ounce of simple water, EXPERIMENTS ON DIGESTION. 191 and placed them together in the axilla. At the same time, he breakfasted on two ounces of boiled salted lean beef, bread, and a pint of coffee. At 12 o'clock M. I took from the stomach one ounce of its contents, not fully digested, bread principally re- maining, reduced to a pulp. Compared with the gastric juice and food in the vial, the particles of meat seemed rather more dissolved. Stomach about half empty. At 1 o'clock P.M. stomach empty and clean. At 8 o'clock, 30 minutes, a. m., on the 3d, I added one drachm fresh gastric juice to the vial of gastric juice and chopped beef, and one drachm of water, to the watery mixture, and placed them together in the axilla. On the 4th, the beef in the gastric juice not being completely dissolved, I added two drachms fresh gastric juice to it, and two drachms of water to the aqueous mixture. Continued them on the bath, or in the axilla. The watery portion began now to smell quite foetid. At 8 o'clock on the 5th, the meat in the gastric juice was completely dissolved, and a fme reddish-grey sedi- ment had fallen to the bottom of an opaque gruel-like fluid, with a pellicle of gre^dsh-white particles on the top. The aqueous portion had become more fcetid. The par- ticles of meat were the same as when first put in, only a little macerated and paler — the fluid transparent, but be- coming darker and a httle greenish — no appearance of solution. On the 10th the contents of the aqueous portion were quite fcetid. The gastric portion was perfectly sweet and bland. 192 experiments and observations. Experiment 34. At 1 o'clock, 30 minutes, p. m., same day, he dined on lean salted beef and bread. Digested in three and a half hours. Experiment 35. Equal parts of alcohol and gastric juice mixed together and agitated, produced a turbid milky-white fluid ; which, after standing at rest, raised a thin white coat of fine loose coagulae on the surface. When the juice and alcohol were first put together, and before agitating, the gastric juice settled to the bottom, and the alcohol remained on the top, indicating that its specific gravity was less than the fluid. Experiment 36. Jan. 2. — At 8 o'clock a. m. stomach empty ; extracted half an ounce of gastric juice. 8 o'clock, 30 minutes, he breakfasted on dr2/ bread and a pint of coffee. 1 1 o'clock stomach nearly full of a pulpous semi-fluid mass resem- bhng thick gruel. 12 o'clock, nearly empty. 12 o'clock, 30 minutes, empty and clean. Experiment 37- At 2 o'clock p. m. he dined on boiled potatoes , a small piece of bread, and drank a glass of water, 4 o'clock, 30 minutes, stomach full of fluids, and quite acrid, of a whitish colour, with particles of potatoes floating about. 6 o'clock, stomach empty. experiments and observations. 193 Experiment 38. Jan. 3. — Kx, 8 o'clock, 30 minutes, a. m. weather plea- sant, smoky, and clear.* Thermometer 38°. Tempera- ture of the stomach 101 1°, immediately after a walk of two miles, producing free perspiration and colour in the face. Extracted half an ounce of gastric juice. At 9 o'clock, 30 minutes, he breakfasted on coldi broiled breast of veal, boiled potatoes and bread. At the same, or within fifteen minutes of the time, I suspended into the stomach, at the aperture, twenty grains of masticated lean veal, contained in a muslin bag. At 12 o'clock a.m. contents of stomach half diminished. 1 o'clock p. m., stomach nearly empty. 1 o'clock, 30 minutes, all gone from the stomach except the musUn bag and contents. The contents appeared to be about half diminished. At 2 o'clock I took out the bag of veal, and, pressing it as dry as I could, without forcing the remaining par- ticles of meat through the cloth, it weighed ten grains, having lost ten grains by digestion in four and a half hours. The veal, when first put in the bag and suspend- ed in the stomach, was of a clay or greyish-white colour, but when taken out and weighed was of a palish red or light flesh colour, and of a glutinous appearance. Experiment 39. At 3 o'clock p.m., same day, dined on broiled veal s^xxd. bread, and drank halfa pint of ?^?a^er. Digested in two hours. • The ahove descriptiou of the weather .being smoky and clear^ looks like an Irish bull, but so it certainly stands in the original. — Editor. R 194 experiments and observations. Experiment 40. Jan. 4. — At 8 o'clock a. m., stomach health}^. Ex- tracted two drachms gastric juice ; came pure, but very slow. At 9 o'clock breakfasted on broiled veal, bread, and coffee. 1 1 o'clock, stomach full ; oil floating on the sur- face, acrid and sharp, excoriating the edges of the aper- ture and skin. 12 o'clock m., chyme passing out. Sto- mach two-thirds empty. 1 o'clock p. m., stomach empty. Experiment 41. At 2 o'clock p. M., same day, he dined on breast of broiled veal and bread, and drank a tumbler of water. 5 o'clock, 30 minutes, stomach nearly empty. 6 o'clock, examined stomach ; chyme of a milky- white colour. 6 o'clock, 30 minutes, chyme still remaining. 7 o'clock, stomach not empty ; took out half an ounce of contents. It was a milky- white fluid, with a peculiar smell and slightly acid and bitter taste. 7 o'clock, 1 5 minutes, sto- mach empty. Experiment 42. Jan. 5 — At 8 o'clock a. m. stomach healthy and clean. Extracted half an ounce of gastric juice. Put it into a vial, and immersed in it fifteen grains of firm tendon of young beef, in a solid piece. Kept it either in the axilla or on the bath for twenty-four hours, when all was com- pletely dissolved. At 8 o'clock, 45 minutes, he breakfasted on broiled veal, bread, and coffee, and kept exercising. 12 o'clock EXPERIMENTS AND OBSERVATIONS. 195 M. Stomach about half empty ; took out half an ounce completely dissolved ; no distinct particles of food to be seen. 12 o'clock, 30 minutes, m., all gone. Remarks. — .This affords an example of the digestion of tendon. Hard solid substances require a greater quan- tity of gastric juice than more tender fibre, and take a longer time for their complete solution. Experiment 43. At 1 o'clock p. M. same day dined on broiled veal and bread, and drank half a pint of water. Digestion com- pleted in four and a half hours. Experiment 44. Jan. 6. — At 8 o'clock a. m. examined stomach. Coats generally healthy ; few small erythematous patches on mucous surface. Secretions pure. Extracted one and a half ounces clear gastric juice, containing less than the usual quantity of mucous flocculi. It ran more freely than common through the tube. More could have been obtained ; but a sensation of faintness, and sinking at the pit of the stomach being felt and complained of, I de- sisted. This sensation has almost uniformly occurred whenever the gastric juice has flowed more freely than usual, and has been suffered to run out to the quantity of one and a half or two ounces, — ^followed by dimness of vision and vertigo on rising. These feelings, however, subside in a few minutes, and he feels as usual, and eats his meals with a good appetite. 196 EXPERIMENTS AND OBSERVATIONS. At 9 o'clock he breakfasted on broiled veal and bread again, as yesterday, and kept exercising. 1 o'clock p. m. stomach nearly empty; several small spots of dark gru- mous blood, exuding from the papillae of the inner coats, made their appearance. 2 o'clock, some appearance of the breakfast still in the stomach. 2 o'clock, 1 5 minutes^ stomach empty. Experiment 45. At 2 o'clock, 30 minutes, p. m. same day, he dined on one pint of barley gruel sweetened with molasses. 4 o'clock, 30 minutes, stomach empty ; none of the bar- ley gruel to be seen. Several small sharp-pointed white pustules made their appearance on the inner surface of the stomach at this time, and the surface generally was of a paler colour, and more flaccid than usual. Experiment 46. I ^Jan. 7 At 8 o'clock a. m. weather cloudy, damp, and disagreeable ; thermometer 48° ; wind N.E. ; tempera- ture of stomach 100°. Less of the small pustules and red patches than yesterday. Colour of the coats natural again, but little secretion of gastric juice this morning. Could obtain only a drachm or two. At 9 o'clock a. m. temperature of stomach 100°. He breakfasted on soft boiled eggs, soft toast, and coffee, 12 o'clock m. sto- mach empty. Experiment 47. ' At 12 o'clock, 30 minutes, m. same day, he dined EXPERIMENTS AND OBSERVATIONS. 197 on three hard-boiled eggs and bread. 3 o'clock, 30 mi- nutes, stomach half empty. Remaining contents acrid. Edges of the aperture excoriated. Some pimples and erythematous patches on the surface of the inner coats. 4 o'clock, 30 minutes, stomach and contents in nearly the same condition as at last examination ; very acrid and sharp ; coats red. 6 o'clock, stomach empty. Remarks These three or four last experiments de- monstrate that a diseased state of the stomach retards digestion. Experiment 48. Jan. 8 — At 8 o'clock, 30 minutes, a. m. examined sto- mach. Coats healthy. None of those white pustules and erythematousjpatches ' observed yesterday and the day before to be seen this morning. Colour of the lining membrane rather paler than common. Surface moist. Extracted half an ounce of gastric juice without difficulty. A slight and momentary vertigo was felt in rising up. No faintness or sense of sinking at the scrobiculus cordis at this extraction. I divided these four drachms of gas- tric juice into two equal parts, and put them into separate vials. In a third vial I put two drachms of simple water. To each of these three vials I added eleven grains of the muscle of a sheep's heart, in an entire piece. Kept one of the vials of gastric juice and meat in the axilla, and placed the other, with the aqueous vial, in a cool place, at about 46°, agitating them alike frequently. At 7 o'clock p. M. the piece in the warm gastric juice 198 EXPERIMENTS AND OBSERVATIONS. was half digested ; the fluid of an opaque reddish-brown colour. That in the cold gastric juice was a very little affected, the surface being covered with a thin glutinous coat, and the fluid a little turbid. That in the water was not in the least affected. The water was perfectly tran- sparent, as when first put in. At 9 o'clock A. M, of the 9th, these several pieces of muscle exhibited the following results. That in the warm gastric juice, when taken out and pressed dry, as when put in, weighed seven and a half grains. That in the cold gastric juice, treated in the same manner, weighed twelve and a half grains, having gained by the absorption of gas- tric juice, one and a half grains. And that in the simple water, weighed eleven grains, the same as when put in, having neither lost nor gained. The tiiree and a half grains that remained in the first vial were in one entire piece, of the same shape as when first put in ; but very soft and tender, hardly able to sus- tain sufficient pressure to be raised by the finger and thumb. It was a mere pulp. The meat in the second vial was increased a little in size ; appeared swollen, soft, slimy and tender ; but had sufficient firmness of texture to resist considerable pressure, when taken up. It was not dissolved. That in the water retained its firmness and was unaltered in appearance, except a paleness of surface, occasioned by maceration. At 8 o'clock next morning (the 10th), the following appearances were evident. The first piece in the warm gastric juice, weighed one and a half grains, having lost in the last twenty-three hours, two grains only. It re- EXPERIMENTS AND OBSERVATIONS. 199 tained the same shape, and was of about the same con- sistence as yesterday. A reddish-brown sediment sub- sided to the bottom of a rich whey-coloured fluid. The second piece, in the cold gastric juice, weighed nine grains and a fraction, having lost about three and a half grains. That in the water was unaltered, and weighed the same as when put in — eleven grains. It may be proper to remark, that the two pieces in the cold gastric juice and water, were moved from their fir^t position in a temperature of about 46°, and placed, for the last twenty-three hours, on the mantle-piece over the fire, in my room, in a temperature of about G0°. The loss of the two and a half grains of meat, in the cold gas- tric juice, was evidently the effect of digestion, occasioned, no doubt, by the increase of fourteen or fifteen degrees of temperature. On the 10th, I added to the vial containing the warm gastric juice and muscle, one-fourth of a drachm of fresh gastric juice, warm from the stomach. Continued it in axilla, and in five hours it was dissolved to a mite, scarcely perceptible. The piece in the cold gastric juice, kept on the mantle- piece, in a temperature between 50° and 60°, till 9 o'clock A. M. of the 1 1th, weighed seven grains, retaining the same shape as yesterday, and a similar texture. The fluid had become more opaque and milky, and the sediment had increased at the bottom. The piece in the water at this time remained unaltered, and weighed precisely the same as at first — eleven grains. At 9 o'clock A. M., I placed both these in the axilla-, 200 EXPERIMENTS AND OBSERVATIONS. At 9 o'clock P. M. the piece remaining in the second vial of gastric juice, placed in the axilla this morning, was nearly all dissolved, one grain only remaining — a soft pulp. The piece in the water remained unaltered, and weighed the same as at first ; but began to emit a strong fetid odour, and in a few days became very putrid. This v/as, however, almost entirely corrected, by the addition of three drachms of fresh gastric juice on the 21st. The meat still continued its original shape and size, and no doubt, its weight, though too putrid to handle, or take out, before the addition of the gastric juice. Placed it on the bath, and it began to digest, and §oon became chymified, lost its fetid smell, and acquired a sharp acid, or rather acrid, taste. Hemarlis The result of this experiment is interesting, in demonstrating the solvent properties of the gastric juice. Maceration alone will not dissolve food, nor separate its nutritious parts. It appears, also, from this experiment, that gastric juice corrects the putrid- tendency of ali- ments ; and that food is more readily dissolved after that tendency has occurred. Experiment 49. January 11. — At 8 o'clock a.m. ; weather clear and dry ; wind S. W. ; thermometer 1 5°. ; temperature of the stomach 100° ; coats healthy. Extracted one ounce of gastric juice, clear and transparent ; few flocculi of mucus ; taste distinctly acid. Complains of the usual sense of distress at the pit of the stomach, and vertigo. EXPERIMENTS AND OBSERVATIONS. 201 At 9 o'clock, 30 minutes, he breakfasted on pork and bread. Digested in four hours and a half. Experiment 50. At 9 o'clock, '30 minutes, a. m., same day, I took three vials, and put into each two drachms pure gastric juice, fresh from the healthy stomach. To one, I added one drachm o^ albumen ; white of egg ; to the second, half a drachm of the yolk, and to the third, another drachm of albumen. Put the two first in axilla, and the other on the mantle -piece. At 9 o'clock p.m. the albumen in the warm gastric juice, in the axilla, had become quite opaque, with loose light-coloured sediment at the bottom. The albumen in the cold gastric juice remained unaltered. That containing the yolk, exhibited the appearance of a mere mixture of fine yellow coagulae, resembling sulphur and milk mixed together. On the 12th, at 8 o'clock p. m., both vials having been continued on the bath, or in the axilla, through the day, the difference observed last evening, between the cold and warm vials of albumen, was very little increased. The yolk was considerably altered from a loose coagulae, generally diffused through the gastric juice, to a fine compact body of coagulae, rising upon the top of a per- fectly clear transparent fluid, free from a particle of sedi- ment. Experiment 51. At 8 o'clock, 30 minutes, a. m. Stomach healthy. Ex- tracted one ounce of gastric juice, a little tinged with 202 EXPERIMENTS AND OBSERVATIONS. yellow, whether from bile or tobacco, it was difficult to determine. He had taken some tobacco into his mouth an hour and a half previous to the examination, and the fluid was not perceptibly bitter. There was a larger por- tion of frothy saliva, and flocculi of mucus, than common. At 10 o'clock, 15 minutes, he breakfasted on boiled salted codfish, bread and coffee. Digested in two hours and a quarter. Experiment 52. January 13. — At 8 o'clock a.m.; weather overcast dry and smoky ; light wind ; thermometer 12° ; tem- perature of stomach 100° and a fraction ; pulse 60, in a recumbent, and 70, in an erect position ; coats not perfectly healthy — general surface rather paler than usual — some red spots and pimples to be seen. Extracted three drachms of gastric juice, slightly acid — not so much as usual — ^less mucus, and more saliva than common. Neither tinge nor taste of bile. At 9 o'clock he breakfasted on boiled fat pork, and bread. At 12 o'clock m. Stomach two-thirds empty. Temperature 100° and a fraction. At 2 o'clock p.m. Stomach nearly empty — very little pulp of bread, and lardaceous fluid to be seen. Has just returned from w^alking two miles or more. Temperature of stomach, 100|°. At 1 o'clock, 30 minutes, stomach empty. Tem- perature 101°. Experiment 53. January 9. — At 2 o'clock p.m. same day, he dined on EXPERIMENTS AND OBSERVATIONS. 203 boiled fat pork, boiled cabbage and bread, and drank a tumbler of water. Digested in five hours. 9 o'clock, temperature 100°. Experiment 54. January 14 — At 8 o'clock 40 minutes, a.m.; weather clear, dry, and serene ; wind N. W. and light ; ther- mometer 28° ; stomach healthy ; coats clean ; tempera- ture of stomach, 100°. Extracted nine drachms of pure gastric juice, distinctly acid, few flocculi of mucus, and a little appearance of frothy saliva. A slight sense of faintness and vertigo ensued, as usual, on rising, after this quantity. At 9 o'clock, breakfasted on boiled fat pork and bread. 12 o'clock m., stomach about half full. Temperature, immediately after walking two and a half miles, 101 1°. 1 o'clock p.m., stomach empty and clean. Temperature 100°. Experiment 55. At 2 o'clock p. m., same day, he dined on boiled fat pork and bread. Digested in three hours. Experiment 6Q. January 14. — At 9 o'clock a. m., I put a solid piece of rib-bone of an old hog, weighing ten grains, into a vial, containing three drachms of pure gastric juice, taken from the stomach this morning. Placed it in the axilla, and continued it there for twelve hours ; then placed it on the shelf, in a cool place, till next morning. January 15 9 o'clock a.m., surface of bone evidently 204 EXPERIMENTS AND OBSERVATIONS. dissolv-ed. Fluid quite opaque. Took out the piece ; and when wiped and dried with blotting paper, as dry as when put in, it weighed just nine grains. Immersed it again in the same juice, and placed it on the sand bath at 100°. Continued it in that temperature for twelve hours, frequently agitating it ; then, as yesterday, placed it on the shelf until next morning. Jan. 16. — 9 o'clock a.m., appearance similar to yesterday morning. Juice a little more turbid. Bone covered with a thin, cineritious coat. Taken out and wiped, the piece weighed eight and a half grains. Immersed again in same fluid, and continued on bath twelve horn's ; then set on shelf again until next morning. Jan, 1 7. — 9 o'clock a. m., very little alteration since yes- terday. Bone taken out and wiped, weighed eight and a quarter grains. Put in again, and continued on bath fifteen hours. Jan. 18. — 12 o'clock m., no change effected since last ex- amination. Bone taken out and wiped, weighed precisely same as yesterday, eight and a quarter gi*ains. Conceiv- ing the solution of the bone had ceased from a deficiency of the gastric solvent, I now added one drachm fresh gas- tric juice, and continued it on the bath again, for eight hours. Jan. 19. — 12 o'clock m., bone taken out, and wiped, as usual, weighed eight grains. Returned to bath, and con- tinued twelve hom's, it v.eighed seven and a half grains. Returned, and continued on bath thirty-six. hours, and frequently agitated between. Jan. 20. and 25. — No visible change was effected. EXPERIMENTS AND OBSERVATIONS. 205 Weight same as on the 19th, seven and a half grains. The solution having ceased again, I added three drachms more of gastric juice, and continued it on the bath twen- ty-four hours. Jan. 27. — 10 o'clock a. m., laraintE of bone separated, and opening on one edge. Fluid more opaque, with a little fine, brown sediment, precipitated to the bottom of the vial. Weight of bone, five and a half grains. Added two drachms of gastric juice, and continued it on the bath for eighteen hours. Jan.2^. — 10 o'clock A.M., laminae of bone opened. Weight- four grains. Returned, and continued on bath twelve hours. — Jan. 29- 10 o'clock a.m., laminse of bone entirelv separated, thin as paper, and elastic as horn. Weight, three and a quarter grains. Returned to bath twelve hours — Jan. 30. 10 o'clock a.m., opacity of fluid, and fine sediment, increased. Weight of bone, two and three- fourth grains. Continued on bath. — Jan. 31. 10 o'clock A.M., no change since yesterday. Weight of bone two and three-fourth grains. Added half a drachm of gas- tric juice, and continued it on bath twelve hours. Feb. 1 — 10 o'clock a.m., laminse very thin and elastic. Weight of bone, two and a half grains. — Took out the pieces of bone, and put them into one drachm fi-esh gas- tric juice, in a separate vial, and continued on bath six hours. — Feb. 2. 10 o'clock a.m., weight of bone, two and a quarter grains. Continued on bath six hours. — Feb. 3. 10 o'clock A.M., weight of bone, two grains, Continued on bath tiU the fifth Feb. 5.10 o'clock a.m., no change since the 3d. Weight of bone same. Added two drachms 206 EXPERIMENTS AND OBSERVATIONS. gastric juice, and continued on bath twelve hours. — Feh. 6. 10 o'clock A. M., bones nearly all dissolved — three- fourths of a grain only remaining. — Feb,7. Weight of bone half a grain, very thin and transparent. The solution not being quite completed, I added two drachms more of gastric juice, and continued it on bath twelve hours. — Feb. 8. 10 o'clock A.M., all dissolved to a mite, quarter of a grain, or less. After the solution of the bone, the menstruum was a greyish-white opaque fluid, nearly of the colour and con- sistence of clear thin gruel, with considerable fine brown sediment at the bottom of the vial, after standing at rest awhile ; and had a peculiarly insipid sweetish taste and smell — not the least fetor or rancidity. Remarks. — It mil be seen in this experiment, that the piece of bone was dissolved in proportion to the quantity of gastric juice applied, and that the solution ceased at longer or shorter intervals, as a larger or smaller quantity was added. When the juice became saturated as well as when the vial was removed from the bath to a low temperature, the solution ceased. It appears that it took fourteen and a half drachms of gastric juice to dissolve ten grains of solid bone. Experiment 57. Jan. 1 5 — At 8 o'clock, a. m., weather cloudy and dry : wind N. E. and light ; ther. 35*; temperature of the stomach, 100°. At 9 o'clock, a.m., he breakfasted on fat pork and bread. 2 o'clock, p. m., stomach empty and clean; temperature, lOT. experiments and observations. 207 Experiment 58. At 2 o'clock, p. M., same day, I put fifteen grains of raw heef steak, divided into small pieces, into three drachms of gastric juice ; and fifteen grains of broiled beef steak, into other three drachms of gastric juice. At the same time, I put the same quantity of broiled steak, di- vided like the others, into three drachms of saliva, fresn from the mouth. I then placed them, all together, alter- nately in the axilla and on the bath, and kept frequently agitating them. At 4 o'clock, the meat in the saliva ex- hibited the appearance of simple maceration ; the other two parcels, in the gastric juice, were considerably dimi- nished and partially dissolved, the fluid of an opaque whitish colour ; the cooked piece, rather the most dis- solved. At 6 o'clock, the salivary portion was not much changed in appearance ; the other two about half dissolved ; the cooked meat in advance of the raw. At 9 o'clock, the salivary portion began to smell slightly fetid, and to change colour. The other two were perfectly bland, and of a sweetish flavour — the meat about three-fourths dis- solved, with a fine brownish-red sediment at the bottom of the vials. Took them all off the bath, and placed them on the shelf till next morning. At 7 o'clock A.M., on the l6th, I placed them again on the bath till 9 o'clock, when the salivary portion had be- come fetid, and was of a greenish colour. The fibres of the meat retained their shape and size ; and had become pale on the surface. Light loose coagulae had fallen to 208 EXPERIMENTS AND OBSERVATIONS. the bottom, leaving a reddish-green coloured fluid above. The gastric portions were almost completely dissolved ; the cooked meat still in advance. At 12 o'clocl^ m., the salivary portion was very fetid. The remaining portions of aliment, taken from the three vials, filtered through thin muslin, and dried with blotting paper, weighed as follows ;- — the broiled meat, in gastric juice, one grain ; the raw meat, in the same, two and a half grains ; and that in the saliva, twelve grains. Remarks. — This experiment demonstrates that saliva does not possess the properties of a solvent ; but facili- tates putrefaction. See also subsequent experiments. It also shews, that raw meat is susceptible of digestion by the gastric juice, though in a less degree than cooked meat. Experiment 59. Jan. 17 — At 9 o'clock a,m. ; weather clear and dry ; wind N.W., and light; ther. 19° ; temperature of stomach, 100° ; coats clean and healthy ; extracted ten drachms of gastric fluid, not so clear and limpid as usual ; some streaks of yellow bile, and more appearance of saliva than common — acid not so perceptible as usual. I divided this into three equal parts, three and one third drachms each. To one part I put fifteen grains firmly coagulated albumen (white of egg), — to the other, fifteen grains ot the soft coagulae of the same — and to the third, fifteen grains raw albumen — and placed them on the bath and in the axilla, alternately. At tlie same time, he breakfasted on three hard boiled eggs, bread and coffee. At 11 EXPERIMENTS AND OBSERVATIONS. 209 O'clock, examined — stomach /ull. Temperature, 100°. Some small red soots. Contents acrid. At 1 2 o'clock M. — just returned from walking one mile, and back again. Weathel clear, dry, and serene. Wind N.W. and light. Th. 23°. Temperature of stomach 102° — nearly empty. Took out one ounce, almost completely chymified ; a little pure oil floating on the surface. Put this on the bath. At 12 o'clock, 30 mins., stomach empty. At 9 o'clock P.M., examined the parcels of albumen, placed in the vials of gastric juice this morning, at 9 o'clock. Of the firm coagulse there remained one and a quarter grains ; of the soft, none ; of the raw, three-fourths of a grain, in loose white coagulae. Experiment 60. Jan. 17 At 12 o'clock, 30 minutes, m., I put twenty- five grains lean broiled mutton^ divided into small pieces, into five drachms of gastric juice, and same quantity into five drachms of gastric juice and fi^esh saliva mixed to- gether, and placed them on the bath. At 9 o'clock p. M. the meat remaining in the gastric luice, taken out and dried with paper, weighed just twelve grains ; that in the mixture of gastric juice and saliva weighed eighteen and three-fourth grains. The texture of the first was considerably more dissolved and tender than the second. Returned them into their respectiv vials again. At 12 o'clock, 30 minutes, m., of the 18th examined them again. The meat remaining in the gastric juice weighed five and three-fourth grains; was soft, gluti- s 210 EXPERIMENTS AND OBSERVATIONS. nous, and of a dirty brown colour. That in the gastric juice and saliva weighed thirteen and a quarter grains ; the texture was quite firm, and retained its fibrous form and reddish bloody colour. Put them in the bath again. At 4 o'clock p. M. of the 1 9th the meat in the gastric juice weighed two grains. Consistence and colour of fluids same as yesterday. The meat in the gastric juice and saliva weighed nine and a half grains. Fluids of a reddish-brown colour, and less precipitate. In ten days the salivary mixture became very putrid, but the gastric portion was perfectly sweet, and so continued for thirty days or more. Experiment 61. Jan. 1 8. — With a view to ascertain the antiseptic pro- perties of the gastric juice, I took a portion of very pu- trid animal matter, and added to it a quantity of gastric juice. The fetor was at once almost completely correct- ed, leaving only a slight putrescent smell, with the usual flavour of the gastric juice. Experiment 62. At 9 o'clock A. m. same day extracted one and a half drachms of gastric juice, and added it to two and a half drachms of milk. The whole was formed into loose white coagulae in less than five minutes. At 1 o'clock p. m. re- maining coagulae, after filtering through muslin, weighed thirteen grains. Returned it into the vial, and placed it on the bath again. At 9 o'clock no coagulae remaining ; all completely dissolved. experiments and observations. 211 Experiment 63. Jan, 19 — =At 9 o'clock a. m. coats of stomacli perfect- ly healthy and clean. No appearance of morbid action ; tongue clean, and every indication of perfect health. There was no free fluid in the gastric cavity until after the elastic tube was introduced, when it began slowly to distil from the end of the tube drop by drop, perfectly transparent, and distinctly acid. I obtained about one drachm of this kind, and then gave him a mouthful of bread to eat. No sooner had he swallowed it than the fluid commenced flowing more freely from the tube, and I obtained two drachms, less pure, however, with saliva and mucus mixed with it, and slightly tinged with yellow bile. The surface of the protruded portion of the villous coat at this time became covered with a limpid fluid, uni- formly spread over its whole surface, distilling from my- riads of very fine papillary points, and trickling down the sides. After letting him rise and walk about two or three minutes, I again introduced the tube, and obtained about two drachms more of very pure gastric juice, making in the whole five drachms. Breakfasted on boiled pork and bread. Dined and supped on the same. Experiment 64. Jan. 20. — At 8 o'clock, 30 minutes, a. m. examined stomach ; appearances healthy. Extracted three drachms gastric fluids, coloiu*ed with bile, slightly acid and bitter. It ran more freely than yesterday. At 8 o'clock, 45 mi- 212 EXPERIMENTS AND OBSERVATIONS. nutes, he swallowed four ounces of pure gelatine (ich- thyocoUa) prepared with boiling water, transparent, and of a tremulous consistence. At 9 o'clock" stomach ap- peared nearly as full as usual after eating his ordinary meals ; fluid clear, and of the consistence of the albumen of eggs. It appeared to be the gelatine dissolved, or dif- fused in the gastric juice. The juice and the liquid ge- latine so much resembled each other that I could not dis- tinguish them apart. At 9 o'clock, 45 minutes, examined again ; found the stomach almost entirely empty ; was just able to obtain two drachms of fluid. It appeared to be a mixture of gelatinous chyme, gastric juice, and flocculi of mucus, more opaque and ropy than the gastric juice alone, and more acid than the fluids of the stomach immediately be- fore the gelatine was swallowed. Not the least appear- ance of bile or yellow colour in the gastric cavity or fluids after taking the gelatine ; considerable vertigo followed the extraction of this last fluid. It soon passed over, and he ate his breakfast {jporh and bread) with his usual appetite. Remarks, — The process of the solution of gelatine is difficult to ascertain. It is not subject to coagulation, and the action of the gastric juice is not easily perceived. It is no doubt dissolved by the gastric juice, in the same manner as other aliment is. See subsequent experiments. Experiment 65. To ascertain whether the sense of hunger would be EXPERIMENTS AND OBSERVATIONS. 21 3 allaj-ed without the food being passed through the oeso- phagus, he fasted from breakfast time till 4 o'clock p. m., and became quite hungry. I then put in at the aperture three and a half drachms of lean boiled beef. The sense of hunger immediately subsided, and stopped the bor- borygmus or croaking noise caused by the motion of air in the stomach and intestines, peculiar to him since the wound, and almost always observed when the stomach is empty. Remarks, — This experiment proves that the sense of hunger resides in the stomach, and is as well allayed by putting the food directly into the stomach as when the previous steps have been gone through with. Not that I would deny the utility of the previous processes in or- dinary cases. Even the sense of taste is essential. It is placed as a sentinel, to prevent improper articles from being introduced into the stoma^ch. See also subsequent experiments. Experiment QQ. Jan. 21 . — At S o'clock a. m. examined stomach. Could obtain but few drops of gastric juice. Sent him to exer- cise in the open air for half an hour. Secretions in- creased ; gastric juice flows pure and more freely. Ex- tracted three drachms. At 8 o'clock, 30 minutes, he breakfasted on bread and coffee, and a small piece of lean pork. At 2 o'clock p. m. stomach empty. Extracted two drachms of gastric juice, tinged with yellow bile, and then one drachm of pure transparent juice, distilling by drops from the end of the tube. 214 EXPERIMENTS AND OBSERVATIONS. At 2 o'clock, 30 minutes, 1 put ten grains of raw suet into two drachms of gastric juice tinged with bile, and ten grains of the same into two drachms of pure gastric juice. Placed them both on the bath. At 9 o'clock the piece of suet 'in the juice that was tinged with bile was considerably more dissolved than that in the clear gas- tric juice ; and, when examined with the compound mi- croscope, the globules appeared more numerous and much smaller. This appearance was also clearly perceptible to the naked eye as the mixtures stood in the vials. At 10 o'clock the piece in the yellow juice was all dissolved ; the other not entirely. Remarks This, with other subsequent experiments, indicate that oily or fatty food is sooner digested when there is a small admixture of bile with the gastric juice. Exercise, it seems, promotes the discharge of the gas- tric juice, as well as digestion in the stomach. Experiment 67. Jan. 22 At 8 o'clock, 30 minutes, a. m., stomach clean and healthy. Extracted five drachms of very clear pure gastric juice. The first three drachms ran out quite freely ; the other two drachms distilled by drops. It was not the least tinged with bile, and tasted distinctly acid. Breakfasted on beefsteak^ bread, and coffee. At 1 o'clock p. m. stomach empty. Experiment 68. At 9 o'clock p. m. same day, St Martin having eaten EXPERIMENTS AND OBSERVATIONS. 215 nothing since 2 o'clock, and feeling quite hungry, I put into the stomach, at the aperture, eight ounces of beef and barley soup, introduced gently through a tube with a syringe, lukewarm. It caused no unpleasant sensation, but allayed the sense of hunger. It satisfied the appe- tite, and he said he had no desire to eat. At 10 o'clock he said he felt a little hungry again, and ate eight ounces more of the same kind of soup, which had a similar effect as the other. Experiment 69. Jan, 23. — At 9 o'clock a. m. weather rainy ; wind N.E. and light ; thermometer 39°- Stomach empty, clean, and healthy; temperature of stomach 100|°.* Breakfast- ed on sausage^ bread, and coffee. At 10 o'clock aspect of weather same as at 9 o'clock ; thermometer 40° ; sto- mach full of fluids; temperature 101|°. The spirit be- came stationary at that point after keeping the tube in the aperture eight or ten minutes, after which it did not vary for ten minutes when it was taken out. At 12 o'clock M. he returned fi-om a walk of two miles. Sto- mach nearly empty ; temperature 101^° stationary, after being continued five minutes in the stomach. At 12 o'clock, 30 minutes, stomach empty. Experiment 70. Jan. 24. — At 8 o'clock a.m. weather cloudy and damp ; * In this and the subsequent experiments I used a spirit ther- mometer, taken from Pool's barometer, which varied half a de- gree from those formerly used. 216 EXPERIMENTS AND OBSERVATIONS. wind N. and moderate ; thermometer 39°. Stomach empty, clean, and healthy ; temperature 100^°. Ex- tracted four drachms gastric juice, very little tinged with yellow. At 9 o'clock he returned from a short walk. Tem- perature of stomach the same. Breakfasted on bread and coffee. 12 o'clock, stomach empty. Temperature of the stomach, after walking two miles or more, 101 J°. Experiment 71. At 1 o'clock P.M., same day, St Martin complaining of being quite hungry, I put into the stomach, at the aper- ture, twelve raw oysters, more than middling size. The sensation was allayed, and the appetite satisfied the same as if swallowed. He was not hungry again till half after 4 o'clock, when he ate a dozen more of the same kind of oysters with bread. At 10 o'clock p.m. stomach empty and clean. Weather damp and rainy. Wind N. E. and brisk. Temperature of the stomach, 992°* He had been covered in bed, and sleeping, for two and a half hours, from which I awoke him to introduce the thermometer. He fell asleep again during the examination — only awoke while putting in and taking out the glass tube. Experiment 72. January 25. — At 6 o'clock a.m. ; wind southerly and light; thermometer 36° ; examined stomach before rising from his bed ; temperature 99° ; extracted fifteen drachms gastric fluid. It flowed out unusually free ; was rather more opaque, and contained less fiocculi of mucus than common, for the quantity. Particles of the EXPERIMENTS AND OBSERVATIONS. 217 bread eaten with his oysters, at 4 o'clock 30 minutes, yesterday, were distinctly to be seen in this parcel of the juice. At 8 o'clock 30 minutes ; temperature of the stomach 100|° ; coats clean and healthy ; thermometer 38°. At 9 o'clock he breakfasted on raio oysters and bread. 11 o'clock, temperature of stomach 101°. 12 o'clock M., he returned from a walk of two miles ; sto- mach empty ; temperature 102°. Experiment 73. January 26 — At 8 o'clock a. m. ; weather clear and cold ; wind N. W. and light ; thermometer 30° ; sto- mach healthy, empty, and clean ; temperature 100J°. Extracted one drachm gastric juice, containing more than usual flocculi of mucus. At 9 o'clock he breakfasted on sausage, bread, and coffee. 10 o'clock thermometer 34° ; temperature of the stomach 1 00|°, and full of a heteroge- neous fluid. 12 o'clock m., returned from a walk ; stomach empty; temperature 101° and a fraction; weather clear and pleasant; thermometer 39; wind N.W. and moderate. Remarks. — From this, and other experiments, it may be clearly inferred, that in the most natural and healthy states of the stomach, there are little or no fluids of any kind in the "gastric cavity, until excited by aliment or other irritants ; and that digestion, under this condition, is the most rapidly and perfectly performed. Experiment 74. At 2 o'clock p. M. same day, he dined on raw oysters T 218 EXPERIMENTS AND OBSERVATIONS. and bread. 5 o'clock, stomach empty. At 6 o'clock, 40 minutes, immediately after drinking a tumbler of water, of the temperature of 55°, introduced thermometer — spirit rose very slowly, and did not become stationary at the natural temperature until the tube had stood in the stomach for thirty-five minutes. 12 o'clock at night, temperatiu-e 99|°, after sleeping in bed three hours. Experiment 75. Jan. 27. — At 6 o'clock a. m. ; before rising fi^om his bed ; weather cloudy and dry — calm ; thermometer 32= ; stomach empty, clean, and healthy ; temperature 991% spirits stationary in ten minutes. He swallowed a gSl of water at the temperature of 55°, which immedi- ately diffused itself over the interior of the stomach, and discharged some at the aperture, by the side of the stem of the thermometer, which had not been withdrawn. The spirit immediately fell to 70° ; stood at that point one and a half or two minutes, and then began again very slowly to rise. Thirty minutes elapsed after taking the water before the spirit regained the 99th degree. Be- fore the end of that time there was no appearance of water in the gastric cavity. At 9 o'clock, 30 minutes, he ate a full breakfast of fresh broiled beef, mostly fat, bread and coffee^ and continued unusually smart exercise, walking for two hours, till he became fatigued, and per- spired freely. At 1 1 o'clock, 30 minutes ; weather clear ; thermometer 43° ; just returned from walking ; sto- mach contained considerable chyme and pil ; aliment about two-thirds gone ; temperature 101°. At 12 o'clock EXPERIMENTS AND OBSERVATIONS. 219 20 minutes, m., stomach nearly empty ; a small portion of the fluid still remaining, reduced to a more perfect chymous condition, with less oil, and that in much finer globules ; appeared tinged with yellow, and tasted bitter. At 1 o'clock P.M., chyme gone ; very little oil remaining. At 2 o'clock, weather unchanged, temperature of sto- mach 101 J°. No chyme to be seen. A few particles of oil still remaining, floating on the surface of a small quan- tity' of fluid, exhibiting considerable spumous froth and mucus. A circumstance occurred here, not before observed in my experiments, which it may not be unimportant to mention, f.^. — the variations of the temperature observed in moving the thermometer up or down in the stomach. The spirits in the tube varied proportionably to the length of the stem introduced. "VMien the bulb sank down to the pyloric portion of the stomach, to the depth of six or eight inches, the spirit rose to 101 J° ; when only inmiersed two or three inches, it would stand at 100|°, making a difference of three-fourths of a degree. These variations were uniformly observed at every ther- mometrical examination. Be77iarks. — Perhaps the difference of indication of the thermometer, may result from a more complete envelope- ment of the stem in the gastric ca^-ity, at the pyloric ex- amination, and a less one at the splenic. I give the reader possession of the fact, without pretending to ac- count for it with certainty. Experiment 76. At 2 o'clock. 30 minvites, p.m., same dav, he dined on 220 EXPERIMENTS AND OBSERVATIONS. raw oysters and bread. 4 o'clock, 30 minutes, stomach not empty ; food about half gone ; small pieces of heart of oyster, and pulp of bread, to be seen floating in a thin pultaceous fluid, quite acrid and sharp ; no bitter taste or yellow colour. Temperature 101^°. A striking peculiarity in the movement of the spirit in the thermometer was observed in this experiment. It rose from about 68° to its stationary point, 100|°, in less than five minutes after the bulb was put into the stomach. At last examination, 2 o'clock, it was fifteen minutes in making the same range. Sometimes it has been twenty- five or thirty minutes before it became stationary, and under no appreciable difference of circumstances. He had been moderately exercising (walking) immediately before the last examination. At 5 o'clock he returned fi-om walking ; temperature of stomach 101|° ; spirit rose, and became stationary at that point in less than three minutes ; food almost com- pletely chymified, and half gone. jTook out one ounce of thick pultaceous porridge-fike fluid, with some small pieces of the hearts of the oysters, reduced to a jelly-like appearance ; plainly acid, and slightly bitter ; and had the flavour of the oysters. At 6 o'clock, 15 minutes, stomach empty and clean. At 6 o'clock, 30 minutes, he ate a full meal of cold boiled beef (considerable fat) and bread. 10 o'clock, 30 minutes, stomach empt5\ Experiment 77. At 9 o'clock A.M. of the 27th, I mixed one drachm of the clear decoction of coffee with three drachms of fresh EXPERIMENTS AND OBSERVATIONS. 221 gastric juice, with a view to ascertain whether it would destroy tiie flavour of the coffee. It had no perceptible effect. The flavour of coffee remained for ten hours, as distinct as at first. Added half a drachm of loaf sugar to the mixture, and placed it on the bath. It remained there forty-eight hours. No different effect was produced on the flavour of the coffee. It remained the same as at first. Remarks. — It is probable that the decoction of coffee, like many other artificial drinks, does not admit of diges- tion ; possesses no nutritive principles ; and is carried into the circulatory system without much change. Experiment 78. At 1 o'clock, 30 minutes, p. m- of the 27th, I put fif- teen grains firm beef cartilage into three drachms of gas- tric juice, and placed on bath. At 10 o'clock a.m. of the 28th took out and wiped dry, it weighed six and three- fourth grains. At 10 o'clock a. m. of the 29th, it weighed one grain. "VMien put in, the cartilage was cut into different sized pieces ; these retained their original forms till com- pletely dissolved, the largest piece being the last digested. Experiment 79* January 28. — At 6 o'clock, 30 minutes, a. m ^before rising ; weather clear and dry ; wind S.W. and Hght ; thermometer 35° ; stomach empty, clean, and healthy •, temperature 100° and a fraction, — spirit stationary in 222 EXPERIMENTS AND OBSERVATIONS. five minutes. No gastric juice could be procured. Ex- tracted about half a drachm of fluids, principally mucus. At 8 o'clock, 45 minutes, — temperature of the sto- mach 100|° when thermometer was put three or four inches only into the splenic portion, but rose to 101° when the bulb was let down eight or nine inches, to- wards the pyloric extremity. A circumstance occurred here which I had not noticed before. On settling the stem down into the stomach, a strong contraction of the muscular fibres was indicated when the bulb had descended near to the pyloric end, by a sudden and peculiar movement of the tube, com- municated to the thumb and finger that guided it, and also felt by St Martin himself. The stomach appeared to contract at that point forcibly, and grasp the bulb^ giving it a sudden impulse downwards, so much so as to require a quick compression by the thumb and finger to prevent it fi'om slipping suddenly into the pyloric end. This grasping sensation would continue for half a minute or more, and then appear to relax again. This ac- tion occurred every time the bulb passed this point, either up or down. When the bulb was below this point, the spirit rose three-fourths of a degree; when raised above, it fell the same. Sometimes the suction-motion was stronger than at others, and when the stem was re- leased from the fingers, it would be drawn down towards the pyloric end, its whole length, ten or eleven inches, occasioning considerable distress, vertigo, and a sense of sinking at the scrobiculus cordis. At. 9 o'clock, he breakfasted as yesterday, and kept EXPERIMENTS AND OBSERVATIONS. 223 quiet most of the time in a recumbent position, on a couch. At 1 1 o'clock, aspects of weather same as in the morning ; thermometer 46° ; contents of stomach about two-thirds diminished; temperature 100|°, at three or four inches deep, and a fraction less than 101 1° when sunk to the pyloric extremity, varying proportionably to the length of the stem introduced. At 1 2 o'clock, 30 minutes, m. stomach nearly empty; temperature 101°. At 1 o'clock, 30 minutes, stomach empty ; temperature 100|°, splenic end, 101^°, at pyloric end. Experiment 80. At 2 o'clock p. M. same day, he dined the same as yes terday, on raw oysters and bread. Temperature of sto- mach, immediately before eating, 101 J°, at pyloric extre- mity ; 100|° at splenic end. At 4 o'clock, 30 minutes, stomach half empty ; temperature 101|° at pyloric ex- tremity ; rose quick ; took out one drachm of the chyme ; digestion nearly complete ; a few particles of bread and oyster to be seen. At 5 o'clock, 30 minutes, stomach nearly empty; temperature 101 1°, pyloric extremity; rose quick. At 6 o'clock, stomach still contained ali- mentary fluids ; quite acrid and sharp. At 6 o'clock, 40 minutes, stomach empty. At 7 o'clock, he supped on boiled beefsLud bread. Experiment 81. January 29. — At 6 o'clock a. m., before rising — weather clear and dry ; wind N E. and brisk ; thermo- meter 28° ; stomach perfectly healthy, empty, and clean ; 224 EXPERIMENTS AND OBSERVATIONS. temperature 100°, at pyloric extremity, and 99° at the other. No gastric secretion. Could not extract ten drops of either gastric juice, mucus or saliva. At 8 o'clock, 30 minutes, stomach empty ; coats per- fectly healthy, and free from any appear'ance of aphthae, pustules, or red spots ; the mucous coat was even and \miform, soft and smooth ; temperature from 100^° to 1 oof ° ; rose quick. Extracted three and a half drachms pure gastric juice, containing some flocculi of mucus, but no bile. At 9 o'clock, he breakfasted on sausage and bread, and kept exercising; vi^alking smartly for two hours. Returned from walking at i 1 o*clock, 30 minutes ; sto- mach two-thirds empty ; temperature 102° and a fraction, at pyloric end, and 101 1° at the other; rose quick. 12 o'clock, 30 minutes, m., stomach almost empty ; "tempe- rature 101 1,° and 100|°; rose moderately. 1 o'clock p. M. stomach empty. Experiment 82. At 1 o'clock, 30 minutes, p. m., same day, he dined on stewed oysters and bread, and kept still. 5 o'clock p. m. stomach empty ; extracted three and a half drachms pure gastric juice. At 6 o'clock, 45 minutes, stomach empty ; temperature 10tf° and ipO|°; rose moderately. Experiment 83. January 30. — At 6 o'clock, 30 minutes, a.m., weather cloudy and damp ; wind N E. and light ; thermometer 39° ; stomach empty, clean, and healthy ; temperature^ EXPERIMENTS AND OBSERVATIONS. 225 immediately before rising, 99|° and 98|° ; rose slowly. At 9 o'clock, temperature of stomach 101 1° and 100|° rose quick ; extracted three drachms gastric juice ; it came slowly, the last mixed with yellow bile. He break- fasted on beefsteak, bread, and coffee. At 11 o'clock, stomach almost empty; temperature 101|° and 100^°. When the bulb of the glass-tube descended towards the pyloric extremity, the stomach evidently contracted upon it, and drew it forcibly down. If left free to its. own motions, the tube would sink to the pylorus, the whole length of the stem, ten or eleven inches, and then rise again of its own accord. When drawn above this point of apparent contractions into the splenic end of the sto- mach, towards the perforation, the motion of the bulb was reversed, in a direction towards the fundis of the stomach, not inclining, however, to make its exit at the perforation, but took a sort of irregular motion, revolving the tube from right to left, so as to turn it completely around in the space of ten or fifteen seconds. This mo- tion was not always present, nor constantly continuous when present, but interrupted, and alternate with the appearance of contraction at the pyloric end, and dis- tinctly evident only from about one and a half to three hours, or more, after eating, and at a time when the chyme was most rapidly leaving the gastric cavity. At 12 o'clock, 30 minutes, m., he returned from a smart walk, — ^had been all the morning, since breakfast, hard at work wheeling coal, an unusually severe exercise ; temperature 102° and 100|° ; rose quick; stomach empty. 226 experiments and observations. Experiment 84. January 29. — At 9 o'clock, 30 minutes, a.m. — To two drachms of gastric juice, I put one small raw oyster, weighing one drachm ; and to another two drachms of gastric juice, I added one drachm of stewed oyster, set them on the bath, and agitated them frequently. At 5 o'clock, 30 minutes, p. m. the residue of the raw oyster weighed four grains, — that of the stewed, weighed eight and three-fourth grains. Continued them on bath. At 9 o'clock A.M. of the 30th, the raw oyster was com- pletely dissolved, not a particle left, except a trace of dirty-brown sediment, the excrementitious part. A grain only of the heart of the stewed oyster was left, with a trace of the same kind of sediment as in the raw one. The flavour of the oysters was retained to the last, and even the chymous mass partook of it. Remarks In the article here submitted to the action of the gastric juice, cooking hardens the fibre, and ren- ders it less susceptible of digestion than the raw. This is what we should a priori judge, from the known pro- perties of the solvent. Experiment 85. January 30. — At 10 o'clock a. m. I put ten grains of boiled lean beef, ten grains of raw lean beef, each piece whole and undivided, and ten grains boiled lean beef, chopped fine, into three drachms fresh gastric juice, and placed them on the bath, frequently agitating as usual. EXPERIMENTS AND OBSERVATIONS. 227 At 12 o'clock M. of the 31st, examined and weighed them. The raw piece weighed the same as when first put in, the lean boiled beef weighed eight grains, the chopped three grains. Added two drachms gastric juice. At 10 o'clock A. M., February 1st, balance of chopped meat weighed one grain, boiled piece, five grains, raw ten grains. Experiment 86. January 29. — At 10 o'clock a.m., I put three equal parts of cabbage, one part raw, another boiled, and the third shaved fine (raw) and macerated in vinegar, ten grains each, into three drachms of gastric juice, and placed them on the bath. At 5 o'clock, 30 minutes, p. m., I took out and pressed dry the respective parcels. They weighed as follows : the shaved, three and three-fourth grains ; the raw, five and a half grains ; the boiled, six and a quarter grains. At 10 o'clock a.m. of the 30th, took out and examined — the raw weighed five and a quarter grains, the shaved three and a half grains, and the boiled the same as yes- terday evening, six and a quarter grains. I added two drachms gastric juice, and continued them on the bath. At 12 o'clock A. M. of the 31st the raw weighed two grains, the shaved one and a half grains, boiled five grains. Added one drachm of gastric juice. February 1. — Raw weighed one grain, shaved one grain, boiled two and a half grains. Experiment 87. January 30. — At 2 o'clock p. m. he dined on raw oys- 228 EXPERIMENTS AND OBSERVATIONS. ters and bread, and kept still. 5 o'clock, 30 minutes, sto- mach empty; temperature 101|° and 100|° ; spirit rose moderately. 6 o'clock, 45 minutes, he supped on raw oysters and bread. 10 o'clock, stomach empty. Experiment 88. January 31. — At 6 o'clock a.m., before rising, wea- ther rainy ; wind N.E. and light ; thermometer 45° ; sto- mach empty, clean, and healthy; temperature 100° and 98|° ; rose moderately. No fluids in the gastric cavity ; could obtain but half a drachm. The peculiar contrac- tion and relaxation or suction and pulsion-motion, were evidently excited this morning by the introduction of the thermometer, but not near so strong as during chymifi- cation. When the bulb is sunk down low into the sto- mach, and suffered to remain there a minute or two, it gives severe pain and distress at the pyloric extremity, like the cramp or the sensation frequently described by persons suffering from undigested food in the stomach, and leaves a sense of soreness if repeated a few times, as was very evident this morning. At 9 o'clock temperature of stomach 101 1° ; he break- fasted on two and a half ounces of beefsteak, four and a half ounces soft toast, and coffee. At 9 o'clock, 30 mi- nutes, he laid himself down on his pallet, and I set the thermometer into his stomach, and continued faithfully and constantly to observe its motions and variations one hour and forty minutes, until ten minutes past eleven, two hours and ten minutes after eating. At first the sto- mach was full to overflowing of heterogeneous fluids, in EXPERIMENTS AND OBSERVATIONS. 229 much commotion, as indicated by the movement of the aUment, and of that part of the stem left out of the aper- ture nearly four inches. This commotion continued about half an hour, to ten o'clock. It then seemed to subside ; the general muscular action became less, as in- dicated by the stem of the thermometer and motion of the fluids, until half after ten o'clock, when a different motion appeared to commence, indicating considerable forcible contraction upon the bulb of the tube, now about six inches from the aperture towards the pylorus. An irregular turning and twisting of the stem, and a simul- taneous downward movement, was succeeded by an ap- parent relaxation and expulsive motion. These alternate motions and appearances continued to recur every two or three minutes — not uniformly, but at irregular inter- vals. A sense of distress and uneasiness was felt at the point where the bulb lay every time these contractions recurred, so as to occasion involuntary manifestations of pain, expressed in the muscular motions of his face. The thermometer did not perceptibly vary, during all this time, from the usual standard temperature of the interior of the stomach. It was 101|° at the pyloric extremity, and 100^° in the splenic end, and continued so during the whole time, ranging between these two points accord- ing as it was moved higher or lower in the gastric cavity. At this time, 11 o'clock, 10 minutes, the stomach was about half empty, and chymification rapidly advancing. At 12 o'clock, 30 minutes, m. the stomach was empty and clean; temperature 101|° and 100| ; ex- tracted two and a half drachms gastric juice. 230 experiments and observations. Experiment 89. February 1. — At 6 o'clock a. m., before rising, wea- ther clear ; wind N.W. ; thermometer 28° ; stomach empty, clean, and healthy; temperature 100° and 99^° ; rose moderately ; no gastric juice secreted. At 8 o'clock weather clear, and growing cold ; thermometer 26°. Temperature of stomach, immediately before go- ing out, 101° and 100°. Returned in 30 minutes; tem- perature of stomach the same ; extracted four drachms gastric juice. At 9 o'clock he breakfasted on breads sau- sage, and coffee, and kept exercising. 1 1 o'clock, 30 mi- nutes, stomach two-thirds empty ; aspects of weather si- milar ; thermometer 29° ; temperature of stomach 101 1° and 100|°. The same appearance of contraction and di- latation, and alternate piston motions were distinctly ob- served at this examination. 1 2 o'clock, 30 minutes, sto- mach empty. Experiment 90. At 2 o'clock p. m. same day he dined on potatoes and meat. 5 o'clock, weather clear and pleasant ; wind N.W. and light ; thermometer 32° ; stomach nearly empty ; temperature 102° and 101 1°, after walking. 5 o'clock, 30 minutes, stomach empty. Experiment 91. February 2 — At 8 o'clock, 30 minutes, St Martin finished breakfasting on full meal, of two and a half ounces fried sausage, seven and a half ounces warm corn bread, EXPERIMENTS AND OBSERVATIONS. 231 and a pint of coffee. Kept gently exercising for one hour, and then increased his exercise to severe walking two or three miles, for two hours ; stomach full when he started, at 9 o'clock 45 minutes. At 12 o'clock m. returned from walking ; stomach not entirely empty ; oil and bread perceptible. 12 o'clock, 30 minutes, considerable fluid in the stomach, tinged with yellow bile ; no dis- tinct particles of food to be distinguished. 1 o'clock p. m. stomach empty and clean ; extracted two drachms pure gastric juice. Remarks. — Severe exercise in this instance is supposed to have retarded digestion, as well as the peculiar kind of food eaten. Experiment 92. At 1 o'clock, 30 minutes, p. m. same day, he dined on four ounces of fresh boiled beef (cold) and five ounces bread, and continued walking smartly for three and a half hours, till 4 o'clock 45 minutes p. m. ; stomach nearly empty ; dinner almost completely chymified. 5 o'clock stomach empty. Experiment 93. February 3 At 8 o'clock, 45 minutes, extracted four drachms gastric juice. He breakfasted on full meal, two and a half ounces boiled beef, seven and a half ounces bread, and one pint of coffee, and kept perfectly still. 12 o'clock, 30 minutes, m. stomach not empty. 1 o'clock 232 EXPERIMENTS AND OBSERVATIONS. P. M. Stomach empty and clean ; extracted one and a half drachms gastric juice. Remarks — This indicates that a complete state of re- pose is unfavourable to speedy digestion.* Experiment 94. At 1 o'clock, 30 minutes, p. m. same day, he dined on four ounces fresh boiled heef, five ounces of bread, and potatoes. 6 o'clock, stomach not entirely empty, but none of the meat remaining. 6 o'clock, 1 5 minutes, very lit- tle of the bread and potatoes to be seen. 6 o'clock, 30 minutes, stomach empty. Experiment 95. February 3 — At 1 2 o'clock m. I put two equal and entire pieces oi parsnip, ten grains each, one boiled and the other raw ; the same kinds and quantities of carrot ; and the same oi potato, into four drachms of gastric juice, and placed them on the bath. At 12 o'clock m. on the 4th, the vegetables, taken out and wiped, or filtered as dry as when put in, shewed the following result : — The piece of raw parsnip weighed three grains, the boiled one grain ; raw carrot three and one-fourth grains, boiled half a grain ; raw potato eight and a half * A state oi continued repose is certainly unfavourable to diges- tion, but many circumstances indicate that repose, or only mo- derate exertion for a short time, say an hour after a full meal, fa- vours its digestion.— Editor. EXPERIMENTS AND OBSERVATIONS. 233 grains ; boiled, no entire particle could be distinguished ; a fibrous and farinaceous residuum of six grains remain- ed on the filter. At 12 o'clock a. m. on the 5th the pieces of parsnip and carrot were almost entirely dissolved, a grain or two of the raw carrot and fibrous centre of the parsnip only remaining. About a grain of the roughish- white farina of the boiled potato remained. The raw po- tato was a little softened and wasted on the surface, but weighed the same as at last examination, eight and a half grains. Remarks. — This is an illustration of the necessity of tenderness and susceptibility of division of the articles of diet, for speedy solution by the gastric juice. The raw potato retained nearly its weight after the other articles were dissolved. Experiment 96. At 3 o'clock p. M. same day I took two equal quantities, two drachms each, of saliva, acidulated to about the fla- vour of gastric juice, one with acetic, and the other with muriatic acid, and put into each two pieces of parsnip and two of carrot, one of each boiled, and the other raw, each weighing ten grains, and placed them on the bath. At 3 o'clock p. M. on the 4th the carrot in the saliva and muriatic acid had lost nothing, the parsnip only two grains. In the acetous menstruum both kinds remained the same as when put in. The fluids of both were un- altered in their sensible qualities and appearances. After continuing them on the bath, with fi-equent agi- u 234 EXPERIMENTS AND OBSERVATIONS. tation, for twenty-four hours longer, the parsnip in the muriatic menstruum had lost four grains, the carrot no- thing. The parsnip in the acetic mixture had lost six grains, and the carrot four grains, but appeared to have been rather macerated and diffused than dissolved or di- gested. I now mixed them all together, and continued them on the bath for twenty-four hours longer ; at the end of which the whole remaining mass of vegetable matter weighed twelve grains. The fluid appeared now a little more chymous, and was rather turbid. Remarks. — This is an example of a species of solution performed by chemical agents having some resemblance to digestion. It is not at all probable, however, that this mixture was in a state of preparation for the action of the pancreatic and hepatic fluids ; but, if placed in the sto- mach, would require the same action of the gastric juice as other diet would. Experiment 97. February 4. — At 9 o'clock a. m. he breakfasted on two and a half ounces of boiled beef, six ounces of bread, and one pint of coffee. Exercised smartly for three hours. At 12 o'clock, 30 minutes, m. chymification complete ; stomach empty. Experiment 98. February 5. — At 9 o'clock a. m. he breakfasted same as yesterday, and kept still. 1 1 o'clock, stomach nearly EXPERIMENTS AND OBSERVATIONS. 235 fiiU. 12 o*clock M., considerable yet in the stomach, oil and bread plainly to be seen. 12 o'clock, 30 minutes, contents of stomach not yet gone. 1 o'clock p. m., sto- mach almost empty. 1 o'clock, 15 minutes, stomach empty. Experiment 99. February 7 At 8 o'clock, 30 minutes, a. m., I put twenty grains boiled codfish into three drachms gastric juice, and placed them on the bath. At 1 o'clock, 30 minutes, p. m., fish in the gastric juice on the bath was almost dissolved, four grains only re- maining ; fluid opaque, white, nearly the colour of milk. 2 o'clock, the fish in the vial all completely dissolved. Experiment 100. February 7. — At 9 o'clock a. m. breakfasted on boiled codfish and bread. Digested in four hours and a half. Experiment 101. February 8 — At 10 o'clock, 30 minutes, a. m., I put two parcels, ten grains each, of strong cheese, one masti- cated and the other an entire piece, into three drachms gastric juice. At 6 o'clock p. m. the masticated portion was all completely digested, scarcely a trace left on the filter. The entire piece had lost four and three-fourth grains, five and one-fourth grains remaining undissolved, and of the same shape as when put in, having lost its su- perficies only. This piece continued gradually to diminish for twenty-four hours, when it was completely dissolved. 236 experiments and observations. Experiment 102. February 12. — At 1 o'clock, 30 minutes, p.m. he dined on mutton^ and barley soup and bread. Digested in three and a quarter hours. Experiment 103. February 13. — At 2 o'clock, 15 minutes, p. m. he dined on mutton, and barley soup and bread. Digested in three and a quarter hours. Experiment 104. February 14. — At 9 o'clock a. m. I took forty grains masticated broiled beefsteak, divided into two equal parts ; put one into four drachms gastric juice, and the other into four drachms of a mixture of dilute muriatic and acetic acids, reduced with water to the flavour of the gastric fluid as nearly as practicable, three parts of the muriatic to one part of the acetic. Placed them together on the bath. At 6 o'clock p. m. the meat in the gastric juice was all dissolved ; that in the dilute acids, when filtered, left a residuum of nine grains, of a jelly-like consistence. The fluids also differed in appearance. That from the gastric juice was opaque, and of a lightish-grey colour, depositing a brown sediment on standing. The other was also opaque, and of a reddish-brown colour, but de- posited no sediment. Remarks. — This was an attempt to imitate the gastric juice. It was not satisfactory. Probably the gastric juice EXPERIMENTS AND OBSERVATIONS. 237 contains some principles inappreciable to the senses or to chemical tests besides the acid and alkaline substances already discovered in it. Experiment 105. At the same time of the above experiment (104) I put the same quantities of pure divy gelatine (ichthyocolla) into exactly similar quantities and kinds of fluids, and placed them all together on the bath. At 6 o'clock p. M. the gelatine in the gastric juice was all completely dissolved, that in the dilute acids, after be- ing placed on the filter, left a residuum of three grains, of a jelly-like substance. These two fluids differed in ap- pearance. That from the gastric liquor was of an opaque whitish colour, with little fine brown sediment ; that fi*om the acid menstruum was also opaque, but of a reddish- brown colour, and of a thin mucilaginous consistence, with no sediment. One drachm of infusion of nutgalls added to the gas- tric solution, immediately aflPorded a rich cream-like fluid, and slowly precipitated a fine compact sediment. The same quantity of infusion of gall^ added to the other im- mediately formed the whole mass into a coarse brown coagulum. After standing a while, it afforded a large loose brownish sediment, and a light-coloured fluid, which, on standing, became white as milk, and the sediment be- came compact, and remained so. The precipitates, after the addition of the tan, taken out and filtered, weighed as follows ; — that in the gastric solution eighteen grains ; the other forty grains ; the dif- 238 EXPERIMENTS AND OBSERVATIONS. ference of weight being about equal to the quantity of gelatine put in. Experiment 106. February 1 5 At 9 o'clock, 45 minutes, a. m. repeat- ed the last (105) experiment with gelatine^ and the gas- tric juice and dilute acids in the same proportions. At 3 o'clock, 15 minutes, p. m. the gelatine in gastric juice all dissolved to a mere mite ; that in acid mixture nearly so, six grains only remaining on the filter, of a jelly-like consistence. The fluid of the gastric portion had a bluish-white colour, and the other yellowish, or about the colour of dry gelatine. At 6 o'clock, the gelatine in the acid menstruum all dissolved. Fluids of both nearly similar. One drachm infusion of nutgalls added to each, in- stantly formed loose lightish-coloured coagulae in both, threw down a compact sediment in the gastric solution, and left an opaque milky fluid. The coarse coagulae in the acid menstruum continued suspended throughout the mass of fluids, for a long time gradually subsiding. At the end of forty-eight hours, it had become precipi- tated to the bottom into a compact mass, and exhibited distinct particles of the entire undissolved gelatine, mixed with a dirty white-coloured curd-like substance, j Experiment 107. February 15 — At 1 o'clock, 30 minutes, p. m., he dined on boiled cod-fish and bread. Digested in four hours and a half. experiments and observations. 239 Experiment 108. February 16. — At 1 o'clock, 45 minutes, p.m., he dined on mutton soup and bread. 6 o'clock, stomach empty. Digested in four hours and a quarter. Experiment 109. February 19. — At 9 o'clock a.m. I put twenty grains of boiled fat pork, cut fine, into three drachms of clear gastric juice, and the same kind and quantity into three drachms of gastric juice, strongly tinged with yellow bile, with a view to ascertain whether there be any diflPerence in their solvent effects upon fat meats. Placed both upon the axilla. At 1 o'clock p. m. the pork in the gas- tric juice, tinged with bile, dissolved to less than one grain, — that remaining undissolved in the clear juice weighed two grains and a half. Experiment 110. February 20. — At 1 o'clock, 30 minutes, p.m., I put three parcels, ten grains each, of boiled cod-fish, into three separate portions of gastric juice, oTvQpure, another containing bile, and the third, a clear, limpid, slightly acid fiuid, taken from the stomach after active exercise and profuse perspiration, in more abundant quantity than usual. Placed them all on the bath. At 1 o'clock, 30 minutes, p.m., of the 21st, I took out and weighed the three parcels of fish. The result was as follows ; — that in the pure gastric juice weighed two and a half grains, that in the yellow, three grains, and the other, six grains. 240 EXPERIMENTS AND OBSERVATIONS. JRemarks. — This shews that other than oily food is retarded by the admixture of bile in the gastric juice. Experiment 111. February 23. — At 9 o'clock, 45 minutes, p.m., I took out two parcels, one drachm each, of gastric juice, one pure, and the other of the clear limpid fluid, extracted under the circumstances mentioned in the last experi- ment, and put eight grains of lean beef, finely cut, into each, and placed them on the bath together. After being treated alike on the bath for six or eight hours, the resi- duum in the pure gastric juice weighed three grains ; and that in the limpid fluid, six grains and a half. Experiment 112. February 24. — At 9 o'clock, 30 minutes, a.m., having extracted gastric juice, containing a large proportion of yellow bile, I put twenty grains of strong cheese, cut small, into two drachms of it, and the same quantity and kind of cheese, into two drachms of pure gastric juice, placed them together on the bath. At 9 o'clock p.m., residuum in the yellow juice weighed five grains, that in the clear juice six grains ; returned them to the bath. At 9 o'clock A.M. of the 25th, the cheese in the yellow juice all dissolved, of that in the clear juice, two grains remained. Experiment 113. March 26. — At 8 o'clock, 15 minutes, weather clear; stomach empty and healthy; introduced thermometer EXPERIMENTS AND OBSERVATIONS. 241 (Poors glass) three-fourths the length of its tube, eight or ten inches, and continued it five minutes ; spirit sta- tionary at 100|°. At 9 o'clock, suspended through the aperture into the stomach, enclosed in a muslin bag, forty grains of broiled fresh cod-fish^, previously masticated, and imbued with saliva ; and he immediately afterwards breakfasted on the same kind of fish, a small quantity of breads and coffee, and kept exercising moderately. At 11 o'clock, stomach full of fluids. 2 o'clock p. m. chymification complete ; bag empty. Experiment 114. March 27. — At 9 o'clock, 15 minutes, a.m., he break- fasted on fresh broiled fish (flounder J, bread, and coffee^ and kept exercising moderately. 11 o'clock, stomach half empty ; pulp of bread only appeared. 1 1 o'clock, 30 minutes, particles of fish and bread still to be seen in the stomach. 1 o'clock p.m. stomach entirely clear of food; temperature 101°. Experiment 115. 1 took dilute muriatic acid, reduced it to the strength and taste of the gastric juice, as nearly as practicable, three drachms ; dilute acetous acid, to about the same flavour, one drachm — mixed them together, and put into the mixture, one scruple of broiled steak, cut fine ; and the same quantity and kind of meat into four drachms of gas- tric juice. Placed both on the bath. In six hours and three quarters, the meat in the gastric juice, taken and X 242 EXPERIMENTS AND OBSERVATIONS. and filtered, weighed two grains only ; that in the acid mixture, treated in the same way, was not dissolved, but had lost its fibrous fiarm, and was converted into a tre- mulous jelly-like mass, too tenacious to pass through the filter, and weighed more than v^hen first put in. It did not appear like chyme, nor resemble that in the gastric juice. After digesting eight hours longer on the bath, the contents of the acid mixture had become nearly dissolved or diffused, and when run through the filter, left only a very little of the jelly-like mass, so abundant in the first examination. The liquid was now more like, though not exactly similar, to that of the gastric portion ; this being opaque, and of a lightish-grey colour, affording a dark- brown sediment on standing ; that from the acid men- struum, was also opaque, of reddish-brown colour, but de- posited no sediment. Two drachms of the infiision of nutgalls, added to the gastric portion, threw down a fine reddish-brown preci- pitate, and afforded an opaque fluid of similar colour. Two drachms of the infusion, added to the acid mixture^ threw down a more copious precipitate, and left a clearer and thinner fluid, of a yellowish colour, and nearly trans- parent. Experiment 116. A drachm of the concentrated disinfecting solution of chloride of soda, prepared according to the formula of Labarraque, was added to a drachm of an extremely pu- trid mixture of beef, macerated in water, — the putridity NOTE BY THE EDITOR. 243 speedily disappeared, but not more so when a drachm of pure gastric juice was added to a similar quantity of the same putrid mixture. Note hy the Editor, The unsuccessful results obtained by Dr Beaumont from attempting to digest animal food in diluted muriatic and acetic acids, as detailed in several of the preceding experiments, coincide very closely v/ith those described by Muller and Schwann of Berlin, in the " Archiv fiir Anatomic und Physiologic," for 1836, and an abstract ot which is given in the British and Foreign Medical Re- view for July 1 837. The object which these gentlemen had in view was to test the accuracy of Dr Eberle's as- sertion, that " although neither diluted acids nor mucus separately possess the power of dissolving organic sub- stances, that property resides in acidified mucus, which is capable not only of dissolving muscular fibre and albu- men, but also of entirely changing their chemical nature, by converting them into osmazome and salivin."* They began, accordingly, by investigating the action of diluted acids upon animal substances, and found, as Dr Eberle had affirmed, and as the preceding experiments also shew, that nothing resembling digestion takes place. Long maceration in diluted muriatic acid served only to sepa- rate the muscular fibres, but never reduced them into pulj). When, however, a small quantity of mucus was * Prit. and For. Med. Review, July 1037, p. 20J.. 244 NOTE BY THE EDITOR. conjoined with the acid, by adding a portion of the mu- cous coat of the stomach of a calf, for example, a distinct digestive power was immediately manifested, and the whole of the fibre was dissolved. Schwann was at much pains to ascertain in what way the acid and mucus respectively act in bringing about digestion ; and the conclusion to which he was led is, that the acid acts indirectly and merely as a predisposing agent in the decomposition, exactly as the diluted acids act in the conversion of starch into sugar when boiled. Dr Eberle considers the digestive principle to reside in the mucus, but Dr Schwann's experiments prove that this is not the case, and lead him to infer it is either a new principle formed by the action of the acid upon the mu- cus, or some other peculiar principle which exists in the latter, in small quantity, but essentially distinct from it. Hitherto all Schwann's attempts to obtain the digestive principle, whatever it may be in an isolated form, have failed. It ought to be mentioned also, that his experi- ments apply only to substances which are digested in the same manner as albumen, and that the " diges- tive liquor " produced no other change upon gelatine, casein, starch, and gluten, than what is produced by simple acidified water. This latter fact seems to me to shew that however much the digestive liquor may resemble the natural solvent in some particulars, it must still be very different from it in others, for the natural fluid dissolves all kinds of food, whatever their chemical composition. — Editor. MICROSCOPIC OBSERVATIONS. 245 MICROSCOPIC EXAMINATIONS. The following microscopic examinations were made with Jones's compound microscope, in presence of Pro- fessor Dunglison and of Captain H. Smith of the army. They afford, however, very little information on the sub- ject of digestion, and shew that no very satisfactory re- sults are attainable from microscopic examinations of chyme. I. Pure gastric juice exhibited the appearance of wa- ter, except that there were perceptible a very few minute globules. II. The chymous product of the gastric juice and un- masticated lean beef, exhibited globules of various sizes, resembling those of the blood, having a transparent centre and opaque mai'gin, with various very fine filaments of apparently undigested fibrine. III. Product of gastric juice and albumen, exhibited appearances resembling considerably those presented by the gastric juice alone, — ^no distinct globular arrangement. IV. Chyme from gastric juice and tendon of veal, ex- hibited numerous minute, apparently fleshy, particles, — no globular appearance. V. Chyme from gastric juice, and fowl and bread, in the comparatively clear portion (taken without shaking the vial), exhibited a few undissolved particles, and very few globules. A portion taken after shaking the vial, exhibited considerably more particles, and a greater num- ber of globuJ.es. 246 MICROSCOPIC EXAMINATIONS. VI. The product of the same kind of aliment (fowl and bread), macerated in water, exhibited numerous undis- solved particles, with few globules ; the globules not so regularly formed as in the foregoing experiment. VII. Product of gastric juice and soup, made from fresh heef exhibited globules extremely numerous and distinctly formed, far more so, than in any of the preced- ing experiments,— and a few particles of meat. VIII. Impure gastric juice, or that with an admixture of green bile, when taken from the stomach, exhibited numerous amorphous particles, with a few globules. IX. Chyme, artificially formed from pork and bread, exhibited numerous globules of different sizes, apparent- ly oily. X. Chymous product of gastric juice and fat pork, formed in the stomach, exhibited a beautiful appearance of large transparent globules, of different sizes, evidently oily. XI. Fat pork, macerated in purevmter, presented ap- pearances of globules precisely similar to those in the products of digestion. ( 247 ) FOURTH SERIES. Plattsburgh, N. Y. 1833. The following gastric experiments and examinations of the stomach, have been made since the manuscript ot the previous part of this work was prepared for the press, EXAMINATIONS OF THE TEMPERATURE AND APPEAR- ANCE OF THE INTERIOR OF THE STOMACH. I. July 9 — 6 o'clock a. m. ; weather cloudy and damp ; wind W., light ; stomach empty and clean. Introduced glass thermometer at the aperture, bulb nine inches down towards the pylorus, — temperature 100° Fahrenheit, be- fore rising from his bede- ll. July 10. — 6 o'clock a.m. ; weather clear ; wind W., brisk ; thermometer 63° ; stomach empty and clean ; temperature 1 00° before rising. 9 o'clock p. m. weather clear and calm ; thermometer 75° ; stomach empty ; tem- perature 101° after moderate exercise in open air. III. July 11. — 6 o'clock A.M. ; weather cloudy ; wind N.E., brisk; thermometer ^^"^ % stomach empty and clean ; temperature 100° before rising. 8 o'clock, 30 minutes, weather clear and dry ; wind S., brisk ; tempe- rature of stomach 101°, after exercise. 9 o'clock, 30 mi- nutes, p. M. weather hazy ; wind S. W., light ; thermo- meter 75° ; temperature 101°. 248 EXPERIMENTS AND OBSERVATIONS. IV. July 12. — 6 o'clock a.m. ; weather clear; wind W., brisk ; thermometer 70° ; stomach empty ; tem- perature 100|°, after going out into the open air. 9 o'clock p. M. ; weather clear ; wind W., light ; ther- mometer 76° ; temperature 101|° ; stomach empty. V. July 13 5 o'clock, 30 minutes a.m. ; weather clear, serene, and calm ; thermometer 69° ; stomach empty, healthy, and clean ; temperature 99|°j before rising from his bed. 6 o'clock, 30 minutes ; weather same as at last examination ; stomach empty ; tempe- rature 100|°, after rising and walking out in the open air twenty or thirty minutes. 6 o'clock, 45 minutes ; re- turned from a smart walk, exercising so as to produce gentle perspiration ; temperature 101|°. VI. July 1 4. — 5 o'clock, 30 minutes, a. m. ; weather variable ; heavy thunder-shower during the night ; wind S., moderate ; thermometer 75° ; stomach empty ; temperature 100° on rising from bed ; 100|° after walk- ing out into the open air and immediately back. 9 o'clock P.M. ; weather rainy, atmosphere oppressive ; thermo- meter 79° ; wind S., light ; temperature of stomach 102'. St Martin has been in the woods all day picking whortleberries, and has eaten no other food since 7 o'clock in the morning, till 8 at evening. Stomach full of berries and chymifying aliment, frothing and foaming like fer- menting beer or cider ; appears to have been drinking liquor too freely. VIL July 15. — 5 o'clock, 30 minutes, a.m. ; weather clear ; wind W., light ; air damp ; ground wet ; ther- mometer 74° ; stomach • empty ; temperature 100°, EXPEEIMENTS AND OBSERVATIONS. 249 before rising. 7 o'clock, 30 minutes ; weather, wind, &c., same as at last examination ; thermometer 74<^ ; stomach empty ; temperature 102°, immediately after smart exercise. 1 o'clock, 30 minutes, p.m. ; weather clear and pleasant since 8 o'clock (till within fifteen mi- nutes, in which interim, has fallen a light shower of rain) ; wind W., light ; thermometer 74° ; stomach empty ; temperature 100|°. Has been at manual exercise for four hours. 9 o'clock p.m.; weather and wind same; thermometer 72° ; temperature 101|° ; stomach fu of chymous fluid, oil, and pulp of bread and cakes, eaten for supper two hours previous to examination. VIII. July 16 7 o'clock, 30 minutes, a. m. ; weather cloudy ; wind W., light ; thermometer 73° ; stomach empty ; temperature 101°, after rising and before ex- ercising. 9 o'clock p. M. ; weather cloudy, damp, and chilly; thermometer 70°; temperature 101|°. IX. July 28. 9 o'clock a. m. ;. weather clear ; wind N. W., brisk ; thermometer ^^'^ '^ stomach empty ; not healthy ; some erythema, and aphthous patches on the mucous surface. St Martin has been drinking ardent spirits, pretty freely, for eight or ten days past — com-