PASTEUR: LACTIC FERMENTATION 60 



found himself led quite naturally to think of fermenta- 

 tion as a vital act. 



Instinctively, for it was still only instinct, he took his 

 stand by the side of Cagniard-Latour and the vitalists. 

 But, in order to defend his position, it was necessary for 

 him to resort to experiment. 



In collating the dates of his different publications, it is 

 evident that he began at nearly the same time the study 

 of the lactic fermentation and the alcoholic. Why did 

 he devote his first work to the lactic fermentation, a 

 much less important one from the industrial point of 

 view? Without his telling us, it is easy to divine. In 

 the first place, when the fermentation becomes lactic 

 there is produced, in the greatest abundance, this mys- 

 terious amyl alcohol of which we have just spoken. But, 

 from his point of view, there is another deeper reason, 

 that is, that the alcoholic fermentation had already lost 

 its bloom. Liebig and the most determined of his 

 partisans had almost condemned it by admitting that 

 the 3"east was necessary, and that it might be a living 

 organism. Their great argument, as we have said above, 

 was always: what role would you wish us to attribute to 

 the yeast, when we see so many other related fermenta- 

 tions, the lactic fermentation for example, taking place 

 without it, and without anything which resembles it? 



The lactic fermentation was, therefore, in a certain 

 sense, le champ clos on which he must struggle, and I 

 believe I am so much the more in the right in attributing 

 to Pasteur this order of ideas because his argument is 

 confined to the following: All that one does with the 

 yeast, I do with the grayish deposit which I find at the 

 bottom of my flasks in which lactic fermentation is going 

 on. The yeast has an organized aspect: my ferment has 

 also, but it is different and difficult to see, and you have 

 not been able to recognize it because, owing to your idea 



