of the statements just listened to, in the chief cities of the central portion of the United States, St. Louis, Cincinnati, Chicago, the average temperature during the hot season is very high, perhaps, as high as 72° F., and that the water-fall in the same region is something over four inches. In the European cities, as London, Paris, Berlin, the average temperature during the same months is about 62° F., and the water-fall is less than two inches. He had looked this subject up thoroughly, extending over a period of ten consecutive years, and as regards this particular form of disease, it is not seen as we see it here in the United States. With reference to heat being the chief element in the production of the disease mentioned, especially the heat as experienced in cities, it is to be observed, that it is much greater in the night in the cities than in the country. It keeps up, and a continuous degree of heat is maintained, which exerts a prostrating influence especially upon the feeble, the aged, and the infant. In the country relief is obtained from the heat during the night. In the gulf cities also they do not have this disease except in a very slight degree. They also have cool breezes at night, and in most places there is such a relief from the heat of the day that at night a blanket is not uncomfortable; while in the cities of the central portion of the country, there is little or no relief during the night from the heat and the effect soon becomes intensely prostrating. From this continuous heat (and there is a large degree of moisture with it) the infant is especially prostrated.

Now we can do something with the facts we already have, and they are important and suggestive with regard to the nature of this and kindred diseases. They convince us that heat and moisture are the two factors, because it is not until we have moisture added that we have this particular form of disease, and although heat may be the principal factor, moisture does very much in assisting its influence. What, therefore, is suggested in way of treatment but to remove the child as far as possible from the intense heat, from the tenement-house which becomes so intensely hot during the summer months, out and where the child can obtain the influence of purer air and less degree of heat? With reference to the nervous system. being prostrated by the disease, it is perhaps unquestionable, and therefore our treatment should be directed with this fact in view, and avoid all depressing treatment, such as the administration of mercurials, etc. Our treatment should be such as will sustain the system until the nerves can gather force sufficient to keep the

machinery in motion; hence the child should be kept cool, tendency to vomiting arrested, and also action from the bowels.

Dr. E. S. GAILLARD, of Kentucky, remarked, that the action contemplated by the resolutions was for the purpose of obtaining coincident meteorological phenomena rather than specific phenomena, and he was of the opinion that, perhaps, it would be well for the gentlemen to give their testimony. Inasmuch as the records with regard to specific are worthless, as showing any of the phenomena of disease, it is proposed to reach this result by showing the fact of coincident phenomena. He was satisfied that this is the only true plan.

He was able to testify, that, so far as absolute heat is concerned, there must be a singular error with regard to its effect in the production of summer diseases. In times past he practised medicine in Florida, and there, where we have summer diseases always from May to October, we had nothing like a tropical heat, for the mercury seldom rose above 85° F. The nights were always cool, heavy dews occurred, and almost always upon that peninsular portion a blanket at night was not uncomfortable. Yet there was more of this disease, cholera infantum, upon the peninsula than perhaps in any other place in the United States. It seems to be a widespread error that heat is essential to the production of summer diseases.

On the contrary, if we go to the extreme northern latitudes, we have, according to the testimony of Dr. Hayes in the report upon his exploring expedition, the fact that when the heat was exceedingly great during the day along the coast of Greenland, the crew were entirely free from attacks of the ordinary summer bowel troubles. We see from these facts, that in Florida these diseases. prevail extensively without a high degree of average temperature, while in Greenland with the most intense heat there was nothing seen of the disease whatever. There seems, therefore, to be something more than one single factor present in the production of these diseases, and it is for the obtaining of coincident factors that Dr. Davis has introduced his resolutions.

It was at one time thought with regard to cholera, diphtheria, catarrh, and some other troubles, that where they prevailed ozone had reached its maximum degree in the atmosphere, but subsequent experience has shown that it requires something more than this to develop these diseases, and that other factors must be taken into consideration. The ozone factor has led to erroneous conclusions,

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and, perhaps, the factor of heat is leading in the same direction. There is but one way to obtain positive knowledge with regard to the etiology of certain diseases, and that is to take coincident clinical and meteorological phenomena and compare them, and he hoped the Association and the Section upon Practical Medicine would sustain the effort made in that direction.

Dr. H. C. WOOD, of Pennsylvania, remarked that it might possibly seem to the gentlemen that he did not appreciate the necessity of such observations as the one contemplated in the resolutions of Dr. Davis. That was not correct, for he did fully appreciate their value and importance and favored their operation. With regard to the action of heat; it is not the heat of the atmosphere outside of the body which influences the tissues, but the temperature inside. of the body. A man may survive in a dry atmosphere which has a temperature of 150° F., while in an atmosphere which has a temperature of 99° even, if moist, he might be overcome. This can be proved by any one who will take the Turkish and Russian baths. In the Turkish bath a man may withstand a temperature even as high as 180° F., whereas in a Russian bath a temperature of 105° F., certainly 110° F., becomes exceedingly oppressive. simply because in the Russian bath there is no possibility of evaporation taking place from the surface of the body so as to cool it, and the heat accumulates within.

Again, with reference to heat and cold, they are not different. There is no such thing as cold. Cold is simply the withdrawal of caloric. The body is pitched upon a certain plane of caloric, and it makes but little difference whether it be depressed below this plane or lifted above; in either case disease may be developed. When a man is directly exposed to a constant high temperature he may get sunstroke; or, again, if exposed to a persistent high temperature he may get granular degeneration of the muscles and important internal organs, and he dies, and the death is attributed to the disease, when, perhaps, it is due simply to the effect of such long-continued high temperature upon the internal organs. We have in the first case a sudden action of heat which knocks the man down, causes paralysis of the brain, precisely the same as I would a blow from a hammer.

We have a third form of high temperature which he conceived to relate more especially to the production of such diseases as cholera infantum. If we have an infant exposed to the deleterious. influence of tenement houses in our large cities, it is always ex

posed to the influence of poisoned air, and the patient is incapable of withstanding its subtle influence. That child is now exposed to long-continued heat, and, perhaps for the first week, it has no noticeable action upon the body, but the second week, it may be, the nerves begin to weaken, and before the third, there may be developed cholera infantum. It may occur even sooner than this, and it occurs because the nerves are not able to withstand the influence of heat supplementing that of a poisoned atmosphere.

Again, if the patient has an exhausted nervous system, and the temperature suddenly falls, the nervous system is no longer able to withstand the sudden fall.

If we take an animal with an elevated temperature, and plunge him into cold water and keep him there until the temperature is reduced, and then take him out, it will be found that the temperature will fall still lower than it was when the animal was first removed from the water. It is in this manner that a sudden falling in temperature may cause cholera infantum. There is probably a chief cause, which is passive until the last influence begins to be felt, which is probably heat, and when it comes it is like the last straw which breaks the camel's back.

Dr. EDGAR explained that he corresponded with Dr. Stone, of New Orleans, in regard to the prevalence of summer diseases in that region, and he had replied that in New Orleans they had but little of the disease known as cholera infantum.

Dr. W. ULRICH, of Pennsylvania, arose to differ with what has been said as to the effect of heat; as to its exerting the last influence upon this disease. His impression was that heat exerts the first influence. There is, however, another influence which we all have seemed to lose sight of, and that is the influence of light. All will probably agree that cholera infantum cannot be treated successfully as long as the rays of the sun are always in the room. Improper food, and even nursing, also have a powerful influence in the production of the disease, and should enter largely into the study of the causes of this disease.

Heat is the first cause, and then all these other influences come in as secondary to it. These are simply suggestions thrown out for the consideration of the members present.

Dr. J. B. JOHNSON, of Missouri, remarked that he did not regard heat as the prime cause of cholera infantum, and he regarded the health of the mother and the tendency of the child as having more to do, perhaps, with the development of the disease, than any other

cause which can be assigned. He was of the opinion that a great majority of these cases were dependent upon the presence of a tubercular diathesis.

The report was accepted and referred to the Committee of Publication. The resolutions appended were also adopted by the Section. 1st. Resolved, That the thanks of the American Medical Association are hereby tendered to Gen'l Myer, Superintendent of the Signal Service Bureau, for the promptness with which he is preparing to add observations concerning the electric and ozonic conditions of the atmosphere, to those heretofore made, at the several signal stations, and for the readiness he manifests to permit the records in his department to be used for the advancement of medical as well as general science.

2d. Resolved, That the chairman of this Section of the Association be requested to renew the appointment of a special committee of three, whose duty it shall be to promote diligently the work indicated in the foregoing report, and report progress at the next meeting of the Association.

The chair appointed the same committee as before, Dr. N. S. Davis, Chairman.

A paper was then read by Dr. E. H. CLARK, of Massachusetts, on Doses, their Physiological and Therapeutical Import.

Dr. J. B. JOHNSON, of Missouri, remarked that with reference to the manner of administering medicine, he is satisfied there has been a fault in his practice. Where he had not found the immediate results to follow which were desired, the remedy has been abandoned, whereas, if it had been persevered in, perhaps different results would have been obtained. It seemed to him that it is a difficult matter always to determine the dose of a remedy to be given. He did not think that any author could give the dose of many medicines, because diseases are so modified by constitutional peculiarities, and by climate, that we are obliged to give a very wide margin. When he first came to the West with his ideas derived from his teacher, whom he venerated as one of the noblest men in the profession, Dr. J. Bigelow, he soon found that these ideas were to be modified in a most marked manner. Dr. Bigelow had stated that when quinine was given in large doses, it would probably act as an irritant to the stomach, and was apt to produce a congestion of the brain, and that three grain doses were considered as large doses. When, therefore, he found practitioners giving ten and fifteen grain doses it was entirely beyond his com