ON THE ROAD TO FAME 49 



It was in a sugar refinery at Lille, owned by 

 M. Bigo, that Pasteur entered upon the study 

 of fermentations. He approached it equipped 

 with all the knowledge acquired through his 

 work in the tartrates, which must have singu- 

 larly aided him to reach a solution of the prob- 

 lem that had been so long and vainly sought. 

 We cannot follow him through these delicate 

 and difficult experiments, but he arrived at this 

 luminous and unforeseen conclusion that fer- 

 mentation was not a phenomenon of death, as 

 Liebig had thought it, but a phenomenon of 

 life, and this he proved in an irrefutable man- 

 ner. 



His experiments, which were directed more 

 especially to lactic and alcoholic fermentation, 

 showed him that all fermentation was due to 

 the presence of living cells which alone were 

 the active agents of the transformation. These 

 cells had a life of their own, and the phenomena 

 of fermentations were closely connected with it 

 and influenced by the different phases of its 

 evolution, according as these cells were ill, dy- 



