24 LOUIS PASTEUR. 



reputation greater than that possessed by Pasteur, at the time, had 

 attacked the problem and failed. In the year 1865 no remedy 

 had been discovered, no cause was known, and the silkworm 

 industry was threatened with immediate destruction. Pasteur was 

 asked to investigate the question, and at first refused to do so. 

 His success in the study of fermentation had opened to him a 

 prosperous career ; he knew nothing whatsoever of silkworm rais- 

 ing, and he was afraid that the investigation, even if successful, 

 would lead him too far from his own chosen line of work. He 

 was, however, over-persuaded, and finally accepted the task of 

 investigating pebrine, little thinking that it was only the continua- 

 tion of his studies on fermentation, and that along the line opened 

 to him by this investigation he was to find his life-work and 

 world-wide reputation. Pasteur undertook the investigation of 

 pebrine already prepared for his discoveries, for living micro- 

 organisms were for him potent agents in nature. He very soon 

 discovered that the cause of the disease was a microscopic organ- 

 ism living in the moth. He was not the first to discover this 

 organism, for others had seen it and described it. 



That Pasteur succeeded where others failed was due to the fact 

 of his belief in the powers of the microscopic world. Others 

 regarded these organisms of no importance, but Pasteur had 

 become so imbued by his study of fermentation with the import- 

 ant agency of microscopic organisms, that the very first question 

 that he asked was whether living bodies were not the cause of the 

 disease that he had been set to investigate. If organisms could 

 produce fermentations in dead material, why might they not 

 produce disease in living creatures ? The result of his work here 

 we need not dwell upon. It was a brilliant success. It demon- 

 strated that the disease was caused by the organisms, and it 

 devised a remedy against the trouble by simply breeding from 

 healthy moths. The world laughed at him ; those interested in 

 the silkworm industry refused to adopt his methods, as those of a 

 fanatical microscopist, and too simple. He met at first with 

 nothing but opposition, but the man arose to the occasion, and so 

 sure was he that he was right that he again arranged for a public 

 demonstration. An abandoned silkworm farm was put into his 

 hands, and, although at the time an invahd and unable to travel 



