cle, having connected with it a glass tube, one end of which is placed in a vessel containing water. The water will rise slightly in the tube with each inspiration, showing that this act not only tends to draw air into the lungs, but exerts an influence in drawing the blood in the venous system toward the thorax. During the diastole of the heart, however, as has been shown over and over again, there is absolutely no rise of the liquid within the tube, this demonstrating the absence of any so-called suctionforce exerted by the ventricles. Some years ago, a German observer, Dr. Baumgarten, advanced the theory that the mitral valves, which are floated out during the diastole of the ventricles, are afterward closed, not by contraction of the ventricles, but by contraction of the auricles. In conclusion, I must say that I can see no sufficient reasons advanced in the paper for physiologists to change their opinions regarding the functions of the auricles. By the contraction of the auricles, a certain quantity of blood is discharged into the ventricles at each revolution of the heart; and this contraction occurs, under normal conditions, as regularly as that of the ventricles, though less powerfully and occupying but half as much time. DR. AUSTIN FLINT, of New York County.-About forty or fifty years ago, a Fellow of the Association, whom all know and respect, performed some elaborate and able experiments upon animals of larger size than the dog, with special reference to the study of the action of the different portions of the heart. The report of these experiments made by Dr. Moore and Dr. Pennock, contained a description of the action of the auricles. I can cite two or three facts of a clinical nature which have a bearing on the subject under discussion, but prefer to hear from the physiologists, and hope to hear a word from Dr. Moore. DR. E. M. MOORE, of Monroe County.-It is true, as Dr. Flint has remarked, that the observations referred to were performed many years ago, in 1838, when the experimenters were still young and enthusiastic; and these constituted some of our earliest contributions to medical science. At that time, we knew little or nothing of diseases of the heart; and the first incentive to study in this direction was a series of experiments made in Dublin, repeated afterward in Philadelphia by Dr. Pennock and myself, and still later by a committee appointed by a London Society. During our observations, Dr. Pennock and I used sheep, calves, and one old borse. I can recall these experiments as if they were made yesterday; and I have often repeated them before students, upon sheep, and have plainly demonstrated the contraction of the auricle as has just been stated by Dr. Flint, Jr. The time occupied by the contraction of the auricle was about two tenths of the heart's revolution. It was as easy to see the contraction of the auricle as to observe that of the ventricle itself. During diastole there was, as would be expected, a slight falling back of the auricles, not what would be considered the result of a suctionforce, but a dropping back, as it were, into the natural position, the fluid behind flowing into the cavity. Just before the time of the ventricular action, there was a sharp, rapid movement of the auricle; and, when distention of the ventricles had become complete, the muscular walls of these cavities contracted upon their contents. These phenomena could be observed as plainly as any fact in every-day life. The PRESIDENT remarked that the Association would undoubtedly be glad to hear from Dr. Flint any clinical facts having a bearing upon the question, and especially as to whether the fact that the walls of the auricles sometimes became quite thin argued in favor of their non-contraction. DR. FLINT remarked that, while he had said the question was a physiological one, it was not purely so, for we occasionally had opportunities to make clinical observations which have a bearing upon it. He thought he could state a fact in clinical medicine which, next to actual observation of the heart itself, showed active contraction of the auricle. The author of the paper had stated that we sometimes observed a jugular pulse, which, if he understood him aright, he referred exclusively to contraction of the right ventricle. In cases in which there was free communication through an incompetent valve between the right auricle and the right ventricle, we had a jugular pulse; a fact which Dr. Flint believed he was first to point out. This jugular pulse, which was perceptible to the eye and to the touch, preceded the contraction of the ventricle, as was shown by comparing the time of its occurrence with the impulse of the apex of the heart, the first heart sound, or the carotid pulse. But sometimes, although not very frequently, we find a jugular pulse due to contraction of the right ventricle, and another jugular pulse due to contraction of the right auricle, so that he was accustomed to speak of an auricular and a ventricular jugular pulse. The auricular jugular pulse occurred, in these instances, prior to the pulse in the carotid artery, while the ventricular jugular pulse was synchronous with the pulse in the carotid artery. Again, we sometimes hear a presystolic murmur; and, on account of its loudness in many instances, it is difficult to resist the conclusion that it is due, not to mere passive flow of blood from the auricle into the ventricle, but to an active current produced by contraction of the auricular walls. DR. J. W. Ross, of Chemung County, mentioned a case, which he had reported, of rupture of the right auricle, the walls being found at the autopsy to be somewhat hypertrophied, to present some spots of atheroma, with a slight degree of atheroma at the point of rupture, but not sufficient to permit of the accident, unless there had been some force brought to bear by contraction of the auricular walls. He thought there must have been some contraction of the auricular walls to have produced the rupture. DR. LYNDE, in closing the discussion, said with regard to vivisection, that he had made vivisections on dogs and on sheep, perhaps as often as from twenty-five to fifty times. He brought the animals under the influence of chloroform or of ether, worked his way down to the heart, introduced a canula and trocar into the heart, and he had never succeeded, after withdrawing the canula, in getting blood to well up from the auricle through the short canula, while he had not the least trouble in demonstrating the contraction of the ventricles, blood being discharged through the canula at each contraction of the ventricular walls. He had already referred to a case in the Museum at Washington in which, on account of stenosis at the auriculo-ventricular opening, the walls of the auricle had become extremely thinned, entirely precluding the possibility of muscular contraction, if that were the function of this part of the heart. Again, he had also referred to the fact that there were occasionally found large deposits of fat upon the auricles. Foster, in his work on physiology, claimed that experiments made by himself and by others demonstrated a certain degree of suction-power on the part of the ventricles. THE USE OF THE ASPIRATOR IN HYDROTHORAX. By E. D. FERGUSON, M. D., of Rensselaer County. A FEW years ago, I saw in consultation a young man who had been ill for two weeks. His health had hitherto been good. The history and physical examination showed the disease to be an idiopathic pleuritis with effusion, the right pleural cavity being filled to about the upper border of the second rib in front. The breathing being somewhat embarrassed, it was thought best to remove some of the liquid, and, accordingly, four pints of clear, light-amber serum were removed by the aspirator. Two days after the aspiration, he had a chill, with considerable increase of fever (which had been very moderate up to that period of his illness), and I again saw him on the fifth day following the operation. The fluid had increased considerably in quantity, and a specimen obtained by the use of the hypodermic syringe showed a notable turbidity. The aspirator was again used, and forty ounces of a moderately turbid and reddish serum were removed. On the sixth day thereafter, thirty-two ounces of a still more turbid fluid were drawn off. At each operation, I attempted to remove all the fluid that could be taken without giving the patient distress in respiration, and the procedure was suspended short of producing marked thoracic discomfort. It is needless to follow the history of the patient through the separate aspirations for the pyothorax which had then developed, or the drainage of the pleural cavity, which gave an apparent recovery (with marked contraction) in about one year, only to be followed by nephritis, a moderate return of the pyothorax, and eventually by death. This was the third case occurring under my observation in which the management, course, and result had been so nearly alike, that I was led to reflect whether the aspiration had not been an important factor in the production of the pyothorax; and I at once modified my treatment of hydrothorax due to idiopathic pleuritis so far as to abstain from the use of the aspirator unless the dyspnoea, continuous or paroxysmal, due to the effusion, was marked, or the process of absorption was unusually delayed; in either of which instances, however, I have not hesitated to aspirate, although I have discontinued the removal of liquid when operating for dyspnoea, as soon as that symptom had been measurably relieved. I have not, since I saw the case which forms the text for this paper, removed more than a pint of liquid at one aspiration, either to relieve dyspnoea or to induce absorption; and, although facts of this kind do not go far toward establishing a principle, I have not had an instance of pyothorax the result of simple pleuritis since I have thus modified my operative management of these cases. This fact has had a certain amount of value to me as evidence; for, although I have no data from which to give actual numbers, I annually see in private or consulting practice a considerable number of cases of idiopathic pleuritis with effusion. I do not wish to be understood as denying the occurrence of cases of pleuritis in which there is a direct tendency to suppurate, nor shall I pause here to discuss the nature of such cases. Since using the aspirator in this modified and limited manner, I do not have a larger percentage of cases resulting in notable thoracic contraction than under its more frequent and freer use. An operation for the removal of intra-pleural effusion, previous to the introduction of aspiration, was regarded as a measure of considerable gravity; and, although the procedure was regarded as justifiable and necessary in certain cases, the liability to the development of pyothorax was fully recognized. Since the publication of Dr. Bowditch's pamphlet, the perform |