31© EREMACAUSIS OR DECAY. 



only in so far as it is a slow and continued source of am- 

 monia.* 



Now it has been shown in the former part of this work, that 

 ammonia is always present in the atmosphere, so that nitrates 

 might thence be formed in substances which themselves con- 

 tained no azotized matter. It is known also, that porous sub- 

 stances possess generally the power of condensing ammonia ; 

 there are few ores of iron which do not evolve ammoniacal pro- 

 ducts when heated to redness, and ammonia is the cause of the 

 peculiar smell perceived upon moistening aluminous minerals. 

 Thus, ammonia, by being a constituent of the atmosphere, is a 

 very widely diffused cause of nitrification, which will come into 

 play whenever the different conditions necessary for the oxida- 

 tion of ammonia are combined. It is probable that other orga- 

 nic bodies in the state of eremacausis are the means of causing 

 the combustion of ammonia ; at all events, the cases are very 

 rare in which nitric acid is generated from ammonia, in the ab- 

 sence of all matter capable of eremacausis. 



From the preceding observations on the causes of fermenta- 

 tion, putrefaction, and decay, we may now draw several conclu- 

 sions calculated to correct the views generally entertained re- 

 specting the fermentation of wine and beer, and several other 

 important processes of decomposition occurring in nature. 



* According to the observations of Collard de Martigny, ammonia is 

 converted directly into nitric acid when in contact with hydrate of lime 

 and with air, without the intervention of any decaying substance. 



