188 LOUIS PASTEUR. 



obtained with the blood of the cow. Notwithstand- 

 ing the replies of Davaine, which, however, added 

 nothing to the facts already adduced on one side or the 

 other, it was difficult to pronounce decidedly in such 

 a debate. Unprejudiced minds received from these 

 important discussions the impression that Jaillard and 

 Leplat, in producing facts the exactitude of which 

 were admitted by Dr. Davaine himself, had given a 

 blow to the assertions of the latter, and that the 

 subject required, in every case, new experimental 

 studies. 



In 1876, a German physician, Dr. Koch, took 

 up the question. He confirmed the opinion of 

 Davaine, but without in the least producing convic- 

 tion, since he threw no light upon the facts adduced 

 by MM. Jaillard and Leplat, of which, indeed, 

 he did not even deign to speak. At the very same 

 moment when the memoir of Koch appeared in 

 Germany, the eminent physician Paul Bert came 

 forward to corroborate the opinion of Jaillard and 

 Leplat. 



' I can,' said M. Paul Bert, 'destroy the bacteria in 

 a drop of blood by compressed oxygen, inoculate with 

 what remains, and reproduce the disease and death 

 without any appearance of bacteria. Therefore, the 

 bacteria are neither the cause nor the necessary effect 

 of the disease of splenic fever. It is due to a virus.' 



This was indeed the opinion of Jaillard and Lephit. 



