260 THE POPULAR SCIENCE MONTHLY. 



tion, to take at any time. Those who would hasten to protect their 

 flocks and herds by Pastorian " vaccination " against a deadly " char- 

 bon " 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 con- 

 tamination. 



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 de- 

 rive their potency from organic germs (an idea that singularly harmo- 

 nizes 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 Yillemin (in 1865) as to the communicability of tubercle 

 by inoculation, are rendering it probable that this terrible scourge (in- 

 cluding 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 ad- 

 vanced by Professor Klebs four years ago, has lately been the subject 

 of most careful research by Dr. Schuller, of Greifswald, who has 

 shown that every form of tuberculosis can thus be artificially induced, 

 the characteristic micrococcus spreading rapidly in the blood and tis- 

 sues of the animal inoculated with it ; and that if, in an animal so in- 

 fected, any joint is experimentally injured, that joint at once becomes 

 a place of preferential resort to the micrococcus, and the special or ex- 

 clusive 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 hu- 

 man 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 Con- 

 gress by a promising young pathologist, Dr. Creighton. 



Well might Mr. Simon conclude his admirable address as President 

 <>f 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. 



