14 BACTERIA, YEASTS, AND MOLDS 



couraging years they were, too — saddened by the death 

 of his daughter, an attack of paralysis which left him lame 

 for the rest of his life, a burst of skepticism which greeted 

 his discoveries when first announced, and finally by his 

 country's defeat in war with Prussia. To overcome the 

 skepticism and to prove that he had actually controlled 

 the disease, he finally had to hire a silk farm which had 

 been abandoned on account of pebrine, and to show that 

 he could bring it back into healthy condition again. 



Thus Pasteur saved the silk industry for France; but 

 better yet, he had proved the germ theory of disease. For 

 a century or more it had been guessed that diseases might 

 be caused by germs; now Pasteur had proved it. This 

 discovery led to the study of other diseases, and even 

 more important results were brought about. The first of 

 these diseases was anthrax, an extremely serious disease 

 of cattle and sheep. Pasteur conquered this disease by 

 showing how to inoculate animals ^(gainst it. 



Vaccination for anthrax was an entirely new idea at 

 that time. Smallpox vaccination had been known for half 

 a century, ever since the famous discovery of Jenner. 

 Dr. Jenner, a physician practicing in the latter part of the 

 eighteenth century, had happened to hear a remark by a 

 country girl: "I can't take smallpox because I have had 

 cowpox"; and from that had been bom his idea of in- 

 tentionally inoculating people with cowpox to prevent their 

 getting smallpox. As a result, this most dreaded disease 

 of the eighteenth century had been almost wiped out from 

 dvihzed Europe before the time of Pasteur. So vaccination 

 was well known to Pasteur's contemporaries ; but who had 

 ever heard of vaccinating for anthrax? 



