OF ORGANIC COMPOUNDS. 231 



-X 



FERMENTATION AND PUTREFACTION. 



Several bodies appear to enter spontaneously into 

 the states of fermentation and putrefaction,, parti- 

 cularly such as contain nitrogen or azotised sub- 

 stances. Now, it is very remarkable, that very 

 small quantities of these substances, in a state of 

 fermentation or putrefaction, possess the power of 

 causing unlimited quantities of similar matters to 

 pass into the same state. Thus, a small quantity of 

 the juice of grapes in the act of fermentation, 

 added to a large quantity of the same fluid, which 

 does not ferment, induces the state of fermentation 

 in the whole mass. So likewise the most minute 

 portion of milk, paste, juice of the beet-root, flesh, 

 or blood, in the state of putrefaction, causes fresh 

 milk, paste, juice of the beet-root, flesh, or blood, 

 to pass into the same condition when in contact 

 with them. 



These changes evidently differ from the class 

 of common decompositions which are effected by 

 chemical affinity ; they are chemical actions, con- 

 versions, or decompositions, excited by contact 

 with bodies already in the same condition. In order 

 to form a clear idea of these processes, analogous 

 and less complicated phenomena must previously 

 be studied. 



The compound nature of the molecules of an 

 organic body, and the phenomena presented by 

 them when in relation with other matters, point out 

 the true cause of these transformations. Evidence 



