FEBMENTATION. 67 



this oxygen, it seems that the sugar supplies it, and 

 fusel oil, containing little oxygen, is the result. (See 

 the Odoriferous Constituents of Wine.) 



The soluble substance rich in oxygen formed from 

 albuminous bodies, which for the sake of brevity we 

 call extract of ferment, constitutes one-fourth of the 

 substance which exists in the cells.* This may un- 

 dergo further transformation, and is capable of taking 

 up more oxygen, and by so doing decomposes sugar ; 

 hence the substance extracted from ferment by cold 

 water is capable of producing fermentation. 



As this representation of the operation of ferment 

 rests upon experiment, certain important examina- 

 tions made by C. Schmidt are of great value to us in 

 completing it.f He has proved that the change under- 

 gone by the albuminous contents of the ferment cells 

 is not limited to the formation of a highly oxygenated 

 matter soluble in water, and insoluble in alcohol, but 

 that this matter when once formed is subject to further 

 decomposition, in consequence of which ammonia is 

 formed, and may be obtained from the liquid after 

 fermentation by means of sulphate of magnesia and 

 phosphate of soda, as phosphate of ammonia and mag- 

 nesia. We musfc therefore assume that the albu- 

 minous contents of the ferment cells is a conti- 

 nually decomposing body, which during the process 

 of decomposition furnishes ammonia and other by-pro- 



* Scheik. Onderz, deel. ii. p. 461. 



t Ann. der Ch.und. Pharm. vol. Lxi. p. 168. 



