AGRICULTURE WITH CHEMISTRY. 59 



NITROUS ACID. 



Nitrous acid is a compound of phlogisticated air or 

 azotic gas with pure air or oxygen. This combination takes 

 place under different circumstances, particularly by the 

 putrefaclion and decay of animal and vegetable substan- 

 ces. As it forms, it combines either with calcareous 

 matter or alkaline salts; forming saline substances, which 

 are conducive to vegetation. 



The nitrous acid, in the table of affinities, is placed 

 next to that of the vitriolic. 



MARINE, OR MURIATIC ACID. 



This acid is next in affinity to the nitrous, and con- 

 stitutes about one third of muriat of soda, or sea salt. It 

 consists, like all other acids, of a combination of pure air 

 or oxygen with a peculiar basis, ^\hich has not as yet 



H 2 been 



