OF ORGANIC COMPOUNDS. 279 



fore possessing a very complex molecule, which are capable 

 of undergoing the decompositions named fermentation and putre- 

 faction. 



We have seen that certain metals acquire a power which they 

 do not of themselves possess, namely, that of decomposing watei 

 and nitric acid, by simple contact with other metals in the act of 

 chemical combination. We have also seen, that peroxide of 

 hydrogen and the persulphuret of the same element, in the act of 

 decomposition, cause other compounds of a similar kind, but of 

 which the elements are much more strongly combined, to undergo 

 the same decomposition, although they exert no chemical affinity 

 or attraction for them or their constituents. The cause pro- 

 ducing these phenomena will be also recognised, by attentive ob- 

 servation, in those matters which excite fermentation or putrefac- 

 tion. All bodies in the act of combination or of decomposition 

 have the property of inducing those processes ; or, in other words, 

 of causing a disturbance of the statical equilibrium in the attrac- 

 tions of the elements of complex organic molecules, in consequence 

 of which those elements group themselves anew, according to 

 their special affinities. 



The proofs of the existence of this cause of action can be easily 

 produced ; they are found in the characters of the bodies which 

 effect fermentation and putrefaction, and in the regularity with 

 which the distribution of the elements takes place in the subse- 

 quent transformations. This regularity depends exclusively on 

 the unequal affinity which they possess for each other in an 

 isolated condition. The action of water on wood, charcoal, and 

 cyanogen, the simplest of the compounds of nitrogen, suffices to 

 illustrate the whole of the transformations of organic bodies; of 

 those in which nitrogen is a constituent, and of those in which it 

 is absent. 



