84 BACTERIOLOGY. 
Finally, numerous results have been obtained from 
the conversion of the fatty acids and their salts into 
other fatty acids by bacteria, As a rule, the lime-salts 
of lactic, malic, tartaric, and citric acids have been em- 
ployed, these being converted in various acids by the 
action of bacteria, such as butyric, priprionic, valeri- 
anic, and acetic acids; also succinic acid, ethy]l-alcohol, 
and, more rarely, formic acid, have been produced. 
Among the gases formed were chiefly CO, and H. 
Thus Pasteur found that anaérobic bacteria convert 
lactate of lime into butyric acid. 
