A VINOUS SMELL. 313 



from dextrin as well as from different kinds of sugar, 

 when these substances were mixed with caseine and 

 vegetable gluten in water and chalk, and allowed to 

 ferment. The gluten behaves just like caseine. 



The formation of butyric acid developed carbonic 

 acid, and hydrogen gas, at first only from 10 to 15 

 per cent, of the total amount of gas was hydrogen, 

 but afterwards equal volumes of each. 



They afterwards found, what is of great importance 

 for our purpose, alcohol among the products of this 

 fermentation. 



If the production of a copious amount of butyric 

 acid does not check the simultaneous formation of 

 alcohol, then it is certain that during the formation 

 of wine (even before much alcohol was formed), the 

 conditions necessary to the production of a fatty acid 

 from the sugar of grapes might exist. 



The change of sugar into butyric acid is generally 

 thus represented : 



1 equiv. sugar .... C 12 H^ 0*2 



1 butyric acid . . . . C H O* 



4 carbonic acid O O 8 



4 hydrogen gas .... H* 



Such a resolution of sugar, or what is the same thing 

 here, of the cellulose of grape-pulp in wine, is im- 

 probable. But the development of hydrogen gas 

 during the butyric acid fermentation is sometimes 

 quite imperceptible, and sometimes does not occur. 

 It has the same effect upon the reaction if oxygen 



