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260, to take at any time. Those who would hasten to protect their flocks and herds by Pastorian "vaccination" against a deadly "charbon" raging in their neighborhood—as who would not?—can not, in common consistency, refuse Jennerian vaccination for their children.

And, thirdly, we shall be furnished with the means of obtaining, at any time, an original stock of vaccinia, the continuous transmission of which through a succession of heifers will at the same time secure the maintenance of its potency, and exclude the chance of human contamination.

Among the numerous other researches now being followed out on the Pastorian lines, I may notice two as likely to prove of the highest practical importance: those which, in the hands of Drs. Klebs and Tommasi Crudeli, seem likely to demonstrate that marsh-malaria derive their potency from organic germs (an idea that singularly harmonizes with the periodicity which is the special character of the varied forms of disease they induce), and those which, based on the original discovery of Villemin (in 1865) as to the communicability of tubercle by inoculation, are rendering it probable that this terrible scourge (including not only pulmonary consumption, but scrofulous disease in all its varied forms) really depends on the presence of a microphyte, which may be introduced into the body, not merely by direct passage into the blood-current (as in inoculation), but also through the alimentary canal, or even through the lungs. This doctrine, which was first advanced by Professor Klebs four years ago, has lately been the subject of most careful research by Dr. Schüller, of Greifswald, who has shown that every form of tuberculosis can thus be artificially induced, the characteristic micrococcus spreading rapidly in the blood and tissues of the animal inoculated with it; and that if, in an animal so infected, any joint is experimentally injured, that joint at once becomes a place of preferential resort to the micrococcus, and the special or exclusive seat of characteristic tubercular changes—a fact of the utmost practical interest in its relation to human joint-diseases. Another line of inquiry, which has obviously the most important bearing upon human welfare, is the propagability of the micrococcus of tubercle by the milk of cows affected with tuberculosis, a question in regard to which some very striking facts were brought before the Medical Congress by a promising young pathologist, Dr. Creighton.

Well might Mr. Simon conclude his admirable address as President of the Public Health Section of the Congress with these pregnant words: "I venture to say that in the records of human industry it would be impossible to point to work of more promise to the world than these various contributions to the knowledge of disease, and of its cure and prevention; and they are contributions which, from the nature of the case, have come, and could only have come, from the performance of experiments on living animals."—Nineteenth Century.