STIDIES ON FERMENTATION. 275 



globules already formed.* Nothing, however, can be truer than 

 that opinion, and at the present moment, after fifteen years 

 of study devoted to the subject, since the publication to which 

 we have referred, we need no longer say "we think," but 

 instead, " we afiirm " that it is correct. It is, as a matter of 

 fact, to alcoholic fermentation, properly so called, that the 

 charge to which we have referred relates — to that fermentation 

 which yields, besides alcohol, carbonic acid, succinic acid, 

 glycerine, volatile acids, and other products. This fermentation 

 undoubtedly requires the presence of yeast-cells, under the 

 conditions that we have named. Those who have contradicted 

 us have fallen into the error of supposing that the fermentation 



* Pasteur, Me moire sur la fermentation alcoolique, 1860; Annahs de 

 Chimie et de Physique. The word globules is here used for cells. In our 

 researches we have always endeavoured to prevent any confusion of ideas. 

 "We stated at the beginning of our Memoir of 1860, that: "^ We apply the 

 term alcoholic to that fermentation which sugar undergoes under the 

 influence of the ferment known as beer yeast.^' This is the fermentation 

 which produces wine and all alcoholic beverages. This, too, is regarded 

 as the type for a host of similar phenomena, designated, by general 

 usage, under the generic name of ferrnentation, and qualified by the 

 name of one of the essential products of the special phenomenon under 

 observation. Bearing in mind this fact in reference to the nomenclature 

 that we have adopted, it will be seen that the expression alcoholic fermfn- 

 tation cannot be applied to every phenomenon of fermentation in which 

 alcohol is produced, inasmuch as there may be a number of phenomena 

 having this character in common. If we bad not at starting defined that 

 particular one amongst the number of very distinct phenomena, which, 

 to the exclusion of the others, should bear the name alcoholic fermentation , 

 we should inevitably have given rise to a confusion of language that 

 would soon pass from words to ideas, and tend to introduce unnecessaiy 

 complexity into researches which are already, in themselves, sufficiently 

 complex to necessitate the adoption of scrupulous care to prevent their 

 becoming still more involved. It seems to us that any further doubt as 

 to the meaning of the words alcoholic fermentation, and the sense in 

 which they are employed, is impossible, inasmuch as Lavoisier, Gay- 

 Lussac, andThenard have applied this term to the fermentation of su^ar 

 by means of beer yeast. It would be both dangerous and unprofitable to 

 discard the example set by those illustrious masters, to whom we are 

 indebted for our earliest knowledge of this subject. 



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