RESULTS OF PUTREFACTION. 291 



Toarkable to find that, at the moment of escaping 

 from one compound, it enters into combination with 

 another element. This fact is important, and de- 

 serves a little further consideration, for it is found 

 that, at the moment of separation, substances have 

 a peculiar tendency to enter into fresh coml^inations. 



769. Substances in this state, or whilst being set 

 at liberty by the decomposition of compounds which 

 previously contained them, are said to be in the nas- 

 cent state. It is always found that substances which 

 have an affinity for each other, but under ordinary 

 circumstances cannot combine, are able to do so when 

 in the nascent state. 



7J0. All attempts have failed to cause the combi- 

 nation of a mixture of hydrogen and nitrogen gases ; 

 but when these two substances are in the nascent 

 state they combine readily, and ammonia is formed. 



771. The rapidity with which animal substances 

 decay or putrefy depends on moisture, warmth, and 

 air. It has been stated that substances of this kind 

 may be preserved a long time if dry; water is neces- 

 sary to their putrefaction. It is well known that 

 meat may be preserved fresh a long time if frozen, 

 or kept at a temperature below the freezing point of 

 water, whilst, on the other hand, if kept in a warm 

 place, it soon begins to change. 



772. The decomposition of moist animal matter 

 may likewise be accelerated by the mixture of potash, 

 soda, or lime, &c., with it; under these circumstances 

 nitric acid is formed (166), though all the ammonia 



