38 Slack, on a Ferment found in Red French Wine. 



The butyric and other nauseous odours gradually lessened 

 in intensity, and just before disappearing, were accompanied 

 by distinct, though faint, smell of some ether — a feet which 

 may be connected with the function, ascribed by M. Pasteur 

 to his Mycoderma vini cells, of assisting to develop the 

 bouquet of white wine. 



When the smell of butjTic acid and that of the unknown 

 cenanthic ether had disappeared, the liquid remained odour- 

 less for a few days, and mycelium threads, together with 

 cells, chiefly ovoid, became abundant in the ropy mass 

 (Fig. 2). Two thirds of the clear fluid was poured off*, and 



Fig. 2. 



replaced by a weak solution of moist sugar. On this the 

 mycelium threads and their cells now opeiated, the odour of 

 fresh vinegar became apparent, and the liquid acted power- 

 fully in reddening blue litmus paper. 



Chemists obtain butyric acid by the process of Pelouze 

 and Gelis. A solution of sugar is excited to fermentation by 

 mixing it with poor cheese. Lactic acid is formed, and unites 

 with lime, which is added in the form of chalk. The lactate 

 of lime then undergoes a change, carbonic acid and hydrogen 

 are evolved, and butyrate of lime remains. The butyrate of 



