NATURE OF FERMENTATION. 257 



united ; those affinities aiding each other, inasmuch 

 as by virtue of them different elements of the com- 

 pound strive to take possession of the different 

 elements of water. Now since it is found that no 

 body destitute of nitrogen possesses, when pure, the 

 property of decomposing spontaneously whilst in 

 contact with water, we must ascribe this property 

 which azotised bodies possess in so eminent a de- 

 gree, to something peculiar in the nature of the 

 compounds of nitrogen, and to their constituting, 

 in a certain measure, more highly organised atoms. 



Every azotised constituent of the animal or 

 vegetable organism enters spontaneously into pu- 

 trefaction, when exposed to moisture and a high 

 temperature. 



Azotised matters are accordingly the only causes 

 of fermentation and putrefaction in vegetable sub- 

 stances. 



Putrefaction, on account of its effects, as a mixed 

 transformation of many different substances, may be 

 classed with the most powerful processes of deoxida- 

 tion, by which the strongest affinities are overcome. 



When a solution of gypsum in water is mixed 

 with a decoction of sawdust, or any other organic 

 matter capable of putrefaction, and preserved in 

 well-closed vessels, it is found, after some time, that 

 the solution contains no more sulphuric acid, but 

 in its place carbonic and free hydrosulphuric acid, 

 between which the lime of the gypsum is shared. 

 In stagnant water containing sulphates in solution, 



