after chloroform-post hoc, but not propter hoc; they are very alarming, more so than the asphyxia cases, as it is very difficult to rouse up the reflex and cardiac nerves where syncope occurs, and, curiously enough, it seems to occur by emotion or fright irrespective almost of the chloroform. The author, being a believer in the value of the deductive philosophy of Mr. Mill and Mr. Buckle in inquiries, like the present, of a physiological kind, wishes at present simply to state that he finds the immense mass of facts as to chloroform (chiefly experiments on the lower animals instituted by the Biological Society of Paris, as detailed in the very masterly essay of MM. Lallemand, Perin, and Duroy-a mass of facts of the highest importance, only very recently published) entirely agree with and corroborate the clinical views he had the opportunity of laying before this Association. It is a pleasure to be able to state, that every year's additional study of chloroform in London leads to a feeling of greater and greater satisfaction as to its value and safety; that this impression also agrees with clinical experience in other cities of Europe, and even in America, where chloroform has now nearly superseded the use of ether. The author wished the present paper to be short, to be, in fact, complementary of former communications. The aggregate number of deaths from chloroform is very alarming; but there is reason to think that, in nearly all the cases, the points here discussed previously, as to the necessity of good respiration, good pulse, &c., still hold good for all cases. It seems very desirable that the results, however, of the hospital experience of the members of the Physiological Section of this Association could be obtained as to any new facts or observations that may have come under notice; for the entire subject of anaesthetics is, as yet, but in a tentative or rudimentary condition. The physiological data of former discussions were left unsettled and incomplete, as said already, in order that a more full consideration might be given to the exact value of simple syncope as a source of danger. The discussion hitherto, in Dr. Snow's time, as to the nature of death from chloroform, with the consequent precautions to be observed to ensure its safety in practice, had been almost entirely confined to an examination of one questionwhether these accidents arise from what the late Dr. Snow named "cardiac syncope," with engorged state of the right side of the heart, or from simple syncope, the right side not engorged. The more philosophical mode of regarding the subject now is to look on both causes as active: the "cardiac syncope "is a post-mortem result, however, as it is described by Snow, and is in reality death from apnoea or asphyxia, and arises in some manner, most probably from some error in the administration of the chloroform; but the second cause of death, or simple syncope, is due to idiosyncrasy. This advance in our knowledge is of importance as to saving life in these cases: we were before looking, like the knights of old, at only one side of the shield, but now we know the shield has two sides. Having previously described at Oxford the mode in which accidents, by asphyxia or "cardiac syncope," occur through irritation of the laryngeal recurrent nerve, or other more recently described nerves, distributed to the mucous membrane of the larynx and air-passages ("Rosenthal's nerves"), it is only necessary to state that further experience helps to corroborate this view. This form of death by asphyxia or apnoea arises by stoppage of action of the respiratory muscles and diaphragm, and can also be brought about in experiments on the lower animals by any even mechanical irritation of these laryngeal nerves; hence the grave necessity of care, in the early stages of the chloroform administration, not to excite or irritate the larynx by acid or impure chloroform, which, like some gases, at once induces spasm of the glottis, with subsequent signs of asphyxia. This was fully entered into at the Oxford Meeting. Indeed, so sensitive is the larynx, and so peculiar its tolerance of chloroform, that this fact of the irritation of its mucous membrane by a strange vapour is now taken advantage of, and where we have to fear simple syncope or faintness, as in formidable operations like ovariotomy, and where syncope is impending in the middle of such operation, the addition of a drachm or two of ether to the inhaler, or a few drops of ammonia, seldom fails to rouse the most flagging pulse (as easily conceivable) through these very nerves. Explain it how we will, the clinical fact is of the utmost importance. This is shown in another direction in this manner :-if we render an animal deeply narcotic by chloroform, in fact all but dead, and then allow it to come back slowly to its usual condition, there is one point where, if the laryngeal nerves be pinched with a forceps, it causes sudden spasm of the glottis, the diaphragm stops acting, and, for want of breathing, the animal falls back again into a state of narcotism or asphyxia, and may die. With this recent discovery as to these nerves we may perhaps couple the group of facts that there is greatly increased danger attached to surgical operations about the larynx or neck (as observed in practice), arising from cutting or injury of its nerves, or catching them up in forceps whilst tying arteries, &c., some intimately associated with nerves of the cardiac plexus, others with the larynx itself, &c. If the act of breathing freely continues during the administration of chloroform, we may be almost certain all is right, and the pulse good; but if the breathing becomes slow or intermittent, stopping and going on again, we are not so safe. Some patients, it is true, seem to take the chloroform slower than others, but it is a fatal error to push it on; the chloroform will accumulate in the system, and the aftereffects will be tedious, if the surgeon, for want of time or other causes, hastens the administration. Is death from chloroform, so called, sometimes a coincidence? It is well to remember that very marked syncope, and even death from syncope, may occur without the use of chloroform at all: intense sudden pain may cause death and syncope; injury of a tendon, or a large bleeding, or even such a trifling thing as touching the urethra in sounding for stone (as remarked especially by Heurtaloup), may induce most alarming syncope; great weakness from want of food, as in soldiers sometimes after a battle, will also give a great tendency to syncope: so that it is always of advantage to learn more or less of a patient's history when we are about to administer chloroform. Accidents from syncope and chloroform may occur from apprehension of pain, rather than actual shock, or actual pain, or deep chloroform narcotism; hence so many accidents in the early part of the administration, before the patient is unconscious at all. Thus of 125 deaths carefully analysed, fifty-four occurred immediately before operation, forty-two during operation, but none as the result of long-continued narcotism or anesthesia; yet chloroform has now to bear all the obloquy of all fatal accidents in the operating-theatre, a certain large percentage of which are obviously the effect of purely mental causes or fear. Persons with strangulated hernia, about to be operated on, are known to have died before any incision at all (without chloroform), the patients taking the shaving of the pubis for part of the operation. Bichât saw a patient die on the instant of passing a simple seton. Dr. Watson tells of a patient dying suddenly at the sight of a trochar about to be used in tapping the chest. Desault was one day about to perform the operation for stone; the patient did not present anything unusual in his manner, and was placed in the usual position: Desault traced simply a line with his thumb-nail on the perineum; the patient uttered a shriek, and fell stone-dead. Mr. Stanley used to tell of a similar case- -Chopart was about to operate for circumcision on a lad, when the boy fell dead the instant the knife touched him. Garengot had a patient with a thecal abscess, who had a shudder and sudden death on seeing the tendon move. Syncope thus becomes a complication, in modern surgical operations, of much greater seriousness than before. That death occurs not from over-narcotism is at once evident, as it arises from apprehension of pain, the patient being quite conscious when these syncope accidents have occurred. These deaths (and they amount to about thirty in the hundred of all the deaths) are observed to happen while the patient is having the chloroform administered, before the surgical operation (at sight of knives, saws, surgeons' aprons, a crowd of students, dressers, strangers, &c., in the operating-theatre), showing how much wiser it is to have the patient placed under chloroform in the sick-ward, than to be exposed to this mental shock. In some London hospitals it is so, in others the point is not understood; but careful observation leaves no doubt on the author's mind that, next to apnoea or asphyxia, already minutely dwelt upon, this mere coincidence of simple syncope is most to be dreaded Observations made at Sea on the Motion of the Vessel with reference to SeaSickness. By J. W. OSBORNE. The author stated that he had entered upon this investigation during a voyage from Melbourne, not with the interest of a physician, whose object it would be to cure this distressing malady, but rather for the purpose of establishing the nature of the connexion between mechanical movement of the human body, both active and passive, with the phenomena of nutrition and waste, functions which manifested many interesting and remarkable anomalies during an attack of sea-sickness. Many observations of a pathological and physiological character had been made and recorded; but it soon became apparent that to obtain results of real value, the nature, force, and direction of the movements to which the vessel subjected the body, and its several organs, required investigation. To express these mechanical influences, three instruments were contrived and used with satisfactory results. These instruments were exhibited by the author, and the following is a sketch of the description given to the Section. The first consists of a spring balance, capable of suspension from any part of the ship. By placing a known weight in the pan of this instrument, the deflection indicated by the index would be constant under ordinary circumstances on shore. At sea this was not the case, the pan being there subjected to an unceasing oscillatory movement, while the index indicated at one time more, and at another less than the figure on the scale corresponding to the weight used. The range thus obtained depended chiefly upon the severity of the pitching; and if the divisions of the scale represented fractions of the weight used, the alteration in weight of any of the viscera of the human body, with every wave, might be arrived at in fractions of their own weight; such alteration being, of course, apparent only, but acting, nevertheless, upon all supporting ligaments, muscles, &c. exactly as if it were real. It was well known that the pitching motion of a vessel was very potent to produce illness, and in the instrument exhibited, the means were offered for measuring and expressing exactly the intensity of this motion; but it was necessary while recording these readings, to determine what the angular movement the vessel made amounted to. To effect this a divided arc was made use of, which, while its manner of suspension permitted of its accommodating itself to one of the angular motions of the ship, partook for the time being of the other. Opposite to this arc, and from the centre of the circle of which it was a part, a plummet or pendulum, made of a strip of metal, was freely suspended. The part played by the latter was to establish a point from which to read off the number of degrees through which either axis of the vessel passed in pitching or rolling. But as the inertia of the pendulum caused it to be seriously affected by the impulsive movements to which the vessel was subjected in passing through the water, it became necessary to neutralize these irregularities. This was accomplished by placing in rigid connexion with the pendulum a small disk, which travelled through a curved tubular receptacle containing oil, glycerine, or other viscid fluid, which, while it did not interfere with the obedience of the plummet to the action of gravity, effectually prevented the communicated impulses from manifesting themselves in the readings. The third instrument was designed to estimate the force of the impulsive movement above referred to, and was an arrangement of a somewhat complicated character, in which the oscillations of a pendulum, unaffected by the angular movements of the vessel, were read and recorded. These oscillations originate in consequence of the inertia or momentum of the pendulum itself, freely suspended in a ship varying in its rate of motion through the water. Several extended series of observations had been made with these instruments which were not as yet reduced. On Tobacco in relation to Physiology. By T. REYNOLDS. The author commenced his paper by adverting to the value of saliva, which he averred was intended for the purposes of digestion, and ought not to be unnecessarily wasted, which was the case with a vast number of habitual smokers. The purity of the saliva ought to be preserved, which could not be the case if it were tamted with smoke. He pointed to the fact that the people of Israel, as we read in Holy Writ, were not an enfeebled race, because they did not infringe natural laws. The paper proceeded to quote the names of various medical men who were opposed to the practice of smoking; some avowing that tobacco-smoke, being conveyed into the stomach, injured the brain. One doctor had seen leeches fall dead when sucking blood from the veins of a man who smoked, the blood of the smoker being much more impure than that of the non-smoker. Dr. Copland avowed that smoking arrested the growth of the young. Dr. Seymour, in writing to the Earl of Shaftesbury, stated that smoking was a remote cause of insanity, and produced premature constitutional decay; in fact, smoking was attended with many unfortunate tendencies. On the Study of the Circulation of the Blood. By GEORGE ROBINSON, M.D., Fellow of the Royal College of Physicians of London, &c., Newcastle-on-Tyne. The writer commenced by observing that Harvey having established the general law of the circulation of the blood, and expressed an opinion that all the secondary functions depended on it, left to posterity the task of investigating its mode of action in inducing the other phenomena of life. But while every succeeding generation has furnished fresh proof of the importance of this discovery, comparatively little has been done towards elucidating the manner in which the motion of the blood acts in the production of its numerous and diversified effects, although the actions directly dependent on it are not only physiologically interesting, but also play an important part in the production and removal of disease. Among the causes which have interfered with the proper development of Harvey's views, the writer notices the undue prevalence of a metaphysical physiology, and a consequent disregard of the legitimate application of the principles of physical science to the explanation of the actions of the living body. He contends that this preference of the ideal to the real still operates to some extent in the same manner as when Harvey's hydraulic reasoning shocked the prejudices of his contemporaries, and that the doubts still occasionally expressed as to the sufficiency of the heart as the prime mover of the mass of blood, the assumed existence of undemonstrable adjuvant forces, and the affectation of incredulity as to the applicability of the laws of hydraulics to the solution of the physiological questions directly connected with the blood's motion, all evidence the injurious effects of the continued neglect of natural philosophy as a branch of medical education, and the retarding influence on medical science of such inattention to the physical agencies operating in the performance of the vital functions. In further confirmation of this opinion, he alludes to the fact that certain views as to the mechanism of vascular absorption and effusion, which he published many years since as the result of an attempt to explain on hydrodynamic principles some of the uses of the circulation, have neither been received nor refuted by the systematic writers on physiology, who are still satisfied with old doctrines on these subjects, applicable only to stagnant liquids, and quite incapable of accounting for some of the phenomena in question. He then asks on what other principle of research than that adopted by Harvey himself can we ever hope to understand the action of the currents of blood in accomplishing their various uses; and refers to the evident subservience of the structural arrangements and physico-vital peculiarities of the organs of sight, hearing, respiration, speech, motion, &c., to the physical principles involved in each particular function, as a proof of the operation of the general laws of matter in the living body, and of the consequent applicability of hydrodynamic reasoning to the explanation of many of the uses served in the animal economy by the innumerable streams of blood incessantly permeating the tissues. In the application of these principles, it is essential to observe closely the physical and vital properties of the living structures, and to combine, if possible, the knowledge and labours of natural philosophers and physiologists. He therefore concluded by submitting to the Council of the British Association the propriety of appointing a subcommittee to cooperate with the Royal College of Physicians of London (who are specially interested in everything relating to Harvey's fame), for the purpose of investigating the physics of the circulation, and so rendering more intelligible the nature of the connexion existing in the living body between the motion of the blood and the performance of the secondary functions of life. On the Difference of Behaviour exhibited by Inuline and ordinary Starch when treated with Salivary Diastase and other converting Agents. By Professor ROLLESTON, M.D., M.A., F.R.S. : The following were the chief results to which Prof. Rolleston had arrived :I. Inuline from the Dahlia retains sugar with great tenacity, but, by repeated washings, it can be freed from that impurity. II. When thus freed from sugar, it obstinately resists the converting influence of salivary diastase. III. This salivary diastase was obtained from human saliva, and from parotid- and from young animals yet sucking, Dr. Rolleston had found to be ineffectual upon ordinary starch. Bidder's researches were in accordance with his. These results led to the two following practical rules:-1. Artichokes are little likely to act as a substitute for the potato, as they contain inuline vice starch. 2. Starch-foods are useless in the early months of infancy, as salivary diastase at such a period is inactive. Tobacco-Smoking: its effects upon Pulsation. By EDWARD SMITH, M.D., F.R.S., Assistant-Physician to the Hospital for Consumption, &c., Brompton. Dr. Smith had recently made a series of observations, chiefly upon medical men, which showed that in some persons tobacco-smoking greatly and rapidly increased the rate of pulsation. The experiments were made at 10 P.M., when the rate of pulsation naturally declines (as he had proved by hourly experiments published in his work on the Cyclical Changes of the Human System), and at least four hours after any fluid or solid food had been taken. They were made in the sitting posture, after it had been maintained fifteen minutes, and with the most absolute quietude of body and mind; and thus all influences were eliminated but those due to the tobacco. The rate of the pulsation was taken every minute for a period beginning two or three minutes before the smoking began, and continuing during twenty minutes, or until the pipe was exhausted. The following are the chief results obtained: : Experiment 1.-Pulsation before smoking was 744 per minute. Smoking 6 minutes, 79, 77, 80, 78, 78, 77 per minute=78.1 average. Smoking 7 minutes, 83, 87, 88, 94, 98, 102, 102 per minute=93-4 average. Smoking 8 minutes, 105, 105, 104, 105, 105, 107, 107, 110 per min. 106 average. Pulsation before smoking 79 per minute. Smoking 6 minutes, 81, 81, 81, 83, 82, 82 per minute=81.6 average. 92, 95, 95, 95, 96, 94, 97, 93-93. The maximum increase was 173 pulsations per minute. Experiment 3.-Smoking an empty pipe. Pulsation before smoking 78 pulsations per minute. |