414 



mixture) not only with thrice but with twice or once its own volume 

 of hydrogen, and that thus other substances may be formed, from 

 which, by the addition of new hydrogen, ammonia may result. It 

 is interesting, therefore, to inquire whether either of these conceived 

 possibilities is actually realized in nature ; whether these two im- 

 portant gases do ever actually combine with each other in either of 

 these two proportions. In the symbolic language of chemists, as 

 usually written in these countries, the compoundNHj is well known, 

 being no other than ammonia ; but does NH* or does NHj exist? 



An eminent French chemist, M. Dumas, in examining a sub- 

 stance, which he called oxamide, and which was one of the results 

 of the action of oxalic acid on ammonia, was led to the conclusion, 

 that the last mentioned compound of nitrogen and hydrogen, name- 

 ly NHj, does really exist in nature, and he proposed for it the name 

 oi amide. The same chemist considered it also to exist in the 

 substance formed by heating potassium in ammoniacal gas ; and 

 the same combination, amide, had been (I believe) regarded as a 

 proximate constituent of certain other compound bodies, such as 

 urea, sulphamide, and carbamide, before Dr. Kane's researches on 

 the White Precipitate of Mercury. Yet it has been judged by 

 Berzelius, that the investigations of Dr. Kane have assisted in an 

 important degree to establish the actual existence (der wirklichen 

 existenz) of amide, or of amidogene (as Kane prefers to call it, 

 from its analogy with oxygen and cyanogen), and have thrown 

 much light upon its chemical history and relations. 



In fact, the body oxamide, which seems to have first led Dumas 

 to infer the existence of amide, was one of those organic com- 

 pounds, respecting which it has often been found difficult, by che- 

 mical inquirers, to pass with confidence from the empirical to the 

 rational formula ; from the knowledge of the ultimate elements 

 (or of those which are at present to be viewed as such), and of the 

 proportions in which they combine, to a satisfactory view respecting 

 the proximate elements, or intermediate and less complex combi- 



* The compound NH, or as it is otherwise better written, HN, has been sus- 

 pected to exist, as one of the proximate elements of melamine and of some con- 

 nected bodies. See Gregory's edition of Turner's Chemistry, 1840, page 757. 



