FERMENTATION. 71 



and water, produces scarcely any fermentation. Solu- 

 tion of sugar is much more efficacious than water alone in 

 extracting the protein compound enclosed in the cells. 



The strong endosmotic properties of sugar are well 

 known. 



We may add to this that sugar appears to excite 

 the ferment to the absorption of oxygen, although 

 during the absorption its decomposition is carried 

 on. Further, that lactic, or some other organic 

 acid (tartaric acid in wine), assists in dissolving 

 the albuminous matter, in extracting it from the 

 cells and introducing it into the liquid, by means 

 of which its own oxidation, and with it the decompo- 

 sition of the sugar, is promoted. 



Lastly, Stahl has expressed himself with regard to 

 the principle of fermentation very clearly, and in a 

 form which was announced as new, some years since, 

 and ascribed to Liebig ; he calls it " the molecule in 

 motion." Stahl says, in reference to this, " A body 

 in the act of decomposition may very easily communi- 

 cate this condition to another body in which it has 

 not begun. Indeed, such a body, in which internal 

 movement has already commenced, may easily bring 

 another body, which is still in a state of repose, but 

 disposed to motion, into the same condition of in- 

 ternal motion."* 



The honour of having laid down the fundamental 

 principle of fermentation, and all that which, taken 



* Zymotechnia Fundamental. Frankf. 1734, p. 304. 



