DIFFERENCE OF FERMENTATION AND PUTREFACTION. 293 



It has also been mentioned, that the strong affinity of nitrogen 

 for hydrogen, and that of carbon for oxygen, are the cause of the 

 facility with which the elements of azotized compounds are dis- 

 united ; those affinities aiding each other, inasmuch as by virtue 

 of them different elements of the compounds strive to take 

 possession of the different elements of water. Now since it is 

 fonnd 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 azotized bodies 

 possess in so eminent a degree, to something peculiar in the 

 nature of the compounds of nitrogen, and to their constituting, iti 

 a certain measure, more highly organized atoms. 



Every azotized constituent of the animal or vegetable organism 

 runs spontaneously into putrefaction, when exposed to moisture 

 and a high temperature. 



Azotized matters are, accordingly, the only causes of fermen- 

 tation and putrefaction in vegetable substances. 



Putrefaction, on account of its defects, as a mixed transforma- 

 tion of many different substances, may be classed with the most 

 powerful processes of deoxidation, by which the strongest affini- 

 ties are overcome. 



When a solution of gypsum in water is mixed with a decoc- 

 tion of sawdust, or any other organic matter capable of putrefac- 

 tion, and preserved in well-closed vessels, it is found after some 

 time, that the solution no longer contains sulphuric acid, but in 

 its place carbonic and free hydrosulphuric acids, between which 

 the lime of the gypsum is shared. In stagnant water containing 

 sulphates in solution, crystallized pyrites are observed to form on 

 the decaying roots. 



Now we know that in the putrefaction of wood under water, 

 when air therefore is excluded, a part of its carbon combines with 

 the oxygen of the water, as well as with the oxygen which the 

 wood itself contains ; whilst its hydrogen and that of the decom- 

 posed water are liberated either in a pure state, or as carburetted 

 hydrogen. 



It is evident, that if with the water a substance containing a 

 "large quantity of oxygen, such as sulphuric acid, be also present, 

 the matters in the state of putrefaction will make use of the oxy 



