308 THE LIFE OF PASTEUR 



same time expressed his opinion on the Toussaint fact. This 

 letter was read at the Academic des Sciences. 



" Allow me, before I finish, to tell you another secret. I 

 have hastened, again with the assistance of Messrs. Chamber- 

 land and Koux, to verify the extraordinary facts recently 

 announced to the Academy by M. Toussaint, professor at the 

 Toulouse Veterinary School. 



" After numerous experiments leaving no room for doubt, 

 I can assure you that M. Toussaint 's interpretations should 

 be gone over again. Neither do I agree with M. Toussaint 

 on the identity which he affirms as existing between acute 

 septicaemia and chicken-cholera; those two diseases differ 

 absolutely." 



Bouley was touched by this temperate language after all 

 the verifying experiments made at the Ecole Normale and 

 in the Jura. When relating the Alfort incidents, and while 

 expressing a hope that some vaccination against anthrax 

 would shortly be discovered, he revealed that Pasteur had 

 had "the delicacy of abstaining from a detailed criticism, 

 so as to leave M. Toussaint the care of checking his own 

 results." 



The struggle against virulent diseases was becoming more 

 and more the capital question for Pasteur. He constantly 

 recurred to the subject, not only in the laboratory, but in his 

 home conversations, for he associated his family with all the 

 preoccupations of his scientific life. Now that the oxygen of 

 air appeared as a modifying influence on the development of a 

 microbe in the body of animals, it seemed possible that there 

 might be a general law applicable to every virus ! What a 

 benefit it would be if the vaccine of every virulent disease could 

 thus be discovered 1 And in his thirst for research, considering 

 that the scientific history of chicken-cholera was more advanced 

 than that of variolic and vaccinal affections the great fact of 

 vaccination remaining isolated and unexplained he hastened 

 on his return to Paris (September, 1880) to press physicians 

 on this special point the relations between small-pox and 

 vaccine. "From the point of view of physiological experi- 

 mentation," he said, "the identity of the variola virus with 

 the vaccine virus has never been demonstrated." When Jules 

 Guerin a born fighter, still desirous at the age of eighty to 

 measure himself successfully with Pasteur declared that 

 " human vaccine is the product of animal variola (cow pox and 



