consumption, the intestinal diseases may continue for a long time before we can discover anything abnormal in the lungs, and that, after death from phthisis, in such cases the intestines exhibit tuberculous ulceration."

At the American Medical Association, at its thirty-first annual meeting, held in New York, June 1st, 1880, J. S. Lynch, M.D., Chairman of the Section of the Practice of Medicine, etc., read a most valuable paper, in which he referred the fearful mortality of young children to unsanitary conditions, and dwelt upon the great influence of unwholesome and diseased food as a marked cause of death.

Ruehle regards Villemin's experiments, in reproducing the disease by inoculation of animals with tuberculous matter, as most valuable, and as a complete victory over Laennec's theory.

Jacobi reports that a dog which ate the sputa of his consumptive master died of consumption.

Fleming says: "It is certain that tuberculosis is a somewhat common and very destructive disease among dairy cattle especially, and more especially those of towns." And consumption is one of the most fatal diseases of large cities, and doubtless, to a considerable degree dependent upon this diseased milk.

Marasmus is undoubtedly more or less attributable to the same cause. Infant mortality is frightful in the excessively hot weather of parts of July and August when many causes add to the irritability of the digestive apparatus, rendering the poisonous influences of acid, impure, or tuberculous milk more effective in the production of fatal diseases. In just these debilitating days of heat do cows also suffer most, and the result must be to supply worse milk.

Niemeyer says "that the predisposition to consumption is strongest in persons of feeble and delicate constitution, and is especially so in children poorly nourished. The children fed on the milk of tuberculous cows must, of necessity, suffer in a twofold sense-from bad food and poisonous food also."

In the production of consumption in city children, and especially in the tenement house population, these accumulated and

concentrated in luences are more potential as the quality of the milk and other food is inferior and often deficient in quantity. Cheap food and cheap milk are usually purchased by those who, above all others, suffer most from unsanitary conditions; and generally cheap food and cheap milk are both bad and dangerous especially from tuberculous animals.

From these facts it is apparent that there is great danger in eating uncooked beef, for fear of contracting consumption, if, indeed, cooking does in fact destroy its virus. The sources from which consumption are derived are now known to be infinitely more numerous than the older pathologists suspected.

It is more dangerous to eat the milk of consumptive animals than to eat the meat; for the milk is seldom boiled, while the meat is always cooked. Cooking is a most valuable sanitary measure in vegetable as well as animal articles of food.

Cows living under bad hygienic conditions, as in man, under similar conditions, are predisposed to tuberculosis in themselves and thus their milk becomes poisonous to children who were pre- . viously debilitated by unsanitary conditions, such as are almost inseparable from residence in tenement houses. In the suburbs. of the cities of New York and Brooklyn, most of the cows are diseased from this cause and by being fed on unsound food.

In a future paper I shall pay my special respects to city cows and cow-stables, and I shall hope to show, I trust, that the milk from diseased cows poisons thousands of children, who are supposed to die from cholera infantum, when in fact they die from tubercles of the intestines, which produce irritation sufficient to cause a rapidly wasting diarrhoea. Consumption is infinitely more common in city-kept cows than it is believed to be even by physi cians. I recently called Prof. Chandler's attention to the unusual number of cows crowded into city stables, and, from the fact of his taking copies of notes sent me by James D. Hopkins, D. V. S., of the State Commission for the eradication of pleuro-pneumonia, I feel assured that so efficient a sanitarian as he is will have these shameful nuisances promptly abated, and future dangers to health prevented.

It has been my aim to be suggestive in this paper rather than exhaustive.

A similar paper was read before the Farmers' Club, since which I have had many communications of inquiry, and several complimentary notices in reference to the timely and important character of the subject in a sanitary point of view. I shall feel much gratification in having the subject further illuminated and discussed by medical men and sanitarians.

In closing this article I wish to state that since the foregoing was written, I find that in 1874 Fleming wrote and published a paper on Tuberculosis in Cattle, which I regret not to have seen, and to which he refers in an article on the same subject in his Veterinary Journal of May, 1880. In this last paper I now see that he refers to the possibility that infantile diarrhoea may to some extent be referred to tuberculous milk. This exactly agrees with what I wrote a month previous to the publication of his article, and which gives me great pleasure to learn, since he could not have then seen my paper.

Breeding from tuberculous cows perpetuates the disease by heredity.

Herr Adonis very naturally and correctly regards cows as more subject to the disease than other cattle; and Zippillius is of opinion that bovine tuberculosis is more common than human tuberculosis.

ART. XIII.-LECTURES ON SOME RECENT INVESTIGATIONS INTO THE PATHOLOGY OF

INFECTIVE AND CONTAGIOUS

DISEASES.

By W. S. GREENFIELD, M.D., LONDON, F. R.C.P.

LECTURE I.

G

INTRODUCTION.

ENTLEMEN-The task which devolves upon me of deliv

ering a course of lectures founded on work done at the Brown Institution is one which on many grounds one might gladly avoid, but seeing that it is a duty, I venture to ask your indulgence in its performance.

It falls to the lot of the few to be the discoverers, though many are the researchers. Very few discoveries, almost no scientific discovery, are made by one man alone. The wave of discovery advances like a besieging army: there are multitudes of eager skirmishers pressing forward to the assault, but of the many, one or two, more earnest or more fortunate than the rest, are the first to attain the summit of the breach made for them by others, and are hailed as the earliest victors. Speedily they are joined by others who have followed the same or a slightly different path, and by their united efforts they make the victory sure. Hence for anyone who is engaged in investigation and research to claim for himself the right to speak only of his own observations is at least hazardous, and savors of presumption, more especially if his work runs in the same line as that of any others. If, then, I venture on a consideration of some subjects which to many are already well worn, and if I seem to be following in the track of others, let me ask for indulgence on the ground that they have been matters of personal investigation, that the results

attained by others have been in many cases independently observed by myself, and that they are therefore in some sense original. Of all the topics on which I might address you, none seemed of greater interest and importance at the present time than that of the infective and contagious diseases, and some of the various topics arising out of the intercommunication of disease between animals and man, and between the various classes of animals. I might indeed have chosen a far easier and less intricate subject, such as some one disease or class of diseases amongst the lower animals, its symptoms, morbid anatomy, and treatment. Of several diseases which I have been investigating, I might have selected one and given you in full detail such information as I could respecting it. But many reasons urged me to attempt the more difficult task of trying the vital question of contagion.

The Brown Institution is established for the purpose of studying, investigating and endeavoring to cure the diseases, injuries, and distempers to which animals useful to man may be subject. It therefore not only contemplates the benefit of individual animals, but of the whole animal race useful to man; and this limitation of utility to man leads us directly to believe that those diseases which affect in the highest degree that utility to man, which destroy large numbers of animals yearly, or which are communicable from animals to man or man to animals, must be amongst the most fit objects of study.

I do not think that the enormous and constant prevalence of epidemic and contagious diseases amongst animals, especially those used for food, is at all commonly appreciated. From time to time an epidemic of cattle plague, or pleuro-pneumonia, sweeping off whole herds of cattle, raises an alarm; but those diseases which, like splenic fever, are constantly present, do not attract so much attention, nor are they recognized as sources of danger to human as well as animal life.

Every year our knowledge of the intimate nexus which binds. together our domestic animals and man seems to become closer, and we are slowly becoming aware that the presence of such diseases in animals is fraught with evil consequences to ourselves.