OF BODIES DESTITUTE OF NITROGEN. 329 



'hydrogen of the substance, which corresponds to the 

 attraction of nitrogen for the same element ; and the 

 other is the affinity of the carbon of the substance 

 for its oxygen, which is constant under all circum- 

 jStances. 



When wood putrefies in marshes, carbon and oxy- 

 gen are separated from its elements in the form of 

 carbonic acid, and hydrogen in the form of carburet- 

 ted hydrogen. But when wood decays or putrefies 

 in the air, its hydrogen does not combine with car- 

 bon, but with oxygen, for which it has a much great- 

 er affinity at common temperatures. 



Now it is evident, from the complete similarity of 

 these processes, that decaying and putrefying bodies 

 can mutually replace one another in their reciprocal 

 actions. 



All putrefying bodies pass into the state of decay, 

 when exposed freely to the air, and all decaying mat- 

 ters into that of putrefaction when air is excluded. 

 All bodies, likewise, in a state of decay are capable 

 of inducing putrefaction in other bodies in the same 

 manner as putrefying bodies themselves do. 



CHAPTER VII. 



EREMACAUSIS OR DECAY OF BODIES DESTITUTE OF 

 NITROGEN: FORMATION OF ACETIC ACID. 



All those substances which appear to possess the 

 property of entering spontaneously into fermenta- 

 tion and putrefaction, do not in reality suffer those 

 changes without some previous disturbance in the 

 attraction of their elements. Eremacausis always 

 precedes fermentation and putrefaction, and it is not 

 until after the absorption of a certain quantity of 

 oxygen that the signs of a transformation in the in- 

 terior of the substances show themselves. 



28* 



