OF BODIES CONTAINING NITROGEN. 243 



the form of ammonia when acted on by alkalies. 

 Acids, and increase of temperature, produce the 

 same effect. It is only when there is a deficiency 

 of water or its elements, that cyanogen or other 

 azotised compounds are produced. 



From these facts it may be concluded, that 

 ammonia is the most stable compound of nitrogen ; 

 and that hydrogen and nitrogen possess a degree 

 of affinity for each other, which surpasses the 

 attraction of the latter body for any other element. 



Already in considering the transformations of 

 substances containing no nitrogen, we have seen 

 that a powerful cause effecting the disunion of the 

 elements of a complex organic atom in a definite 

 manner, is the great affinity which carbon possesses 

 for oxygen. But carbon is also invariably contained 

 in azotised compounds, while the great affinity of 

 nitrogen for hydrogen furnishes a new and power- 

 ful cause, facilitating the transposition of their com- 

 ponent parts. Thus, in the bodies which do not 

 contain nitrogen we have one element, and in 

 those in which that substance is present, two 

 elements, which mutually share the elements of 

 water. Hence there are two opposite affinities 

 at play, which strengthen mutually each other's 

 action. 



Now we know, that the most powerful attractions 

 may be overcome by the influence of two affinities. 

 Thus, a decomposition of alumina may be effected 

 with the greatest facility, when the affinity of 



R 2 



