56 DR. E. KLEIN. 



proper material is used ; every one of them inoculated once or 

 twice with it died] — was proved by the fact that they one and 

 all succumbed to anthrax afterwards when inoculated with a 

 different but active material. And this latter circumstance 

 proves at once that they had not been " vaccinated," in the 

 sense of Pasteur, or any other sense, by the first inoculation, 

 that in fact the first inoculation produced absolutely no disease. 

 But, secondly, had the bacillus as such lost its virulence by 

 being taken from the blood and -cultivated in an artificial 

 medium ? Not in the least, because the very same bacillus 

 killed mice in the first few days of the cultivation, and later 

 on it killed guinea-pigs and rabbits within forty-eight hours 

 by typical anthrax, and blood of these animals killed without 

 fail within thirty-six hours. What is more than this, the very 

 same cultivation which failed to kill a mouse or mice at one 

 time, killed ihem without fail at another, provided the bacillus 

 had in the meantime had the opportunity to form spores. And 

 this fact, viz. the presence of spores in the cultivation, is of the 

 utmost importance in respect of the fatal efficacy of the arti- 

 ficially cultivated bacillus on the mice. 



Pasteur, as mentioned above, produced a certain incapability 

 of the bacillus to kill sheep by growing it at 42° — 43° C. By 

 these means he maintains that he can prevent the bacilli from 

 forming spores which prove fatal to sheep when inoculated. I 

 have mentioned above that in my cultivations in neutral pork 



tbey succumbed to it ultimately, thus proving that, thoy were susceptible to 

 the virus, — it remains as the most probable ex))lanation to assume that the 

 virus, although locally introduced, was for some* unknown reasons not carried 

 into the general circulation. That in our instances it was the resistance offered 

 by the tissue of the tail to the life of the Bacillus anthracis, whicii prevented 

 the development of the disease, is not a probable reason, since there exists no 

 real resistance to the anthrax bacillus, of either mice, rabbits, or guinea-pigs 

 to prevent the fatal result generally produced after such incubations. 



A similar negative result after first inoculation I have noticed also in a few 

 of my guinea-pigs, where the fluid had been introduced into the subcutaneous 

 tissue, and also in a sheep. But in botli cases a second inoculation with the 

 same virus produced positive results. The virus was introduced during the 

 first inoculation in suflicieut quantity very safely into the subcutaneous tissue. 



