DETONATION OF CYANOGEN. 



71 



graphite, and that the lamp-black precipitated by the incom- 

 plete combustion of the hydrocarbon also contains a trace 

 of it. 1 



5. Cyanogen. The same test carried out with cyanogen is 



Fig, 5. 



Fig. 6. 



equally successful ; the cyanogen detonates under the influence 

 of the fulminate, and resolves itself into its elements. 

 2ONT = C 2 4- Na. 



Thus we can produce free nitrogen, and amorphous carbon in 

 a highly divided state similar to what is obtained by the 

 electric spark. This carbon marks paper as plumbago will do. 

 Yet it is by no means real graphite, because it will almost 

 totally dissolve, if repeatedly treated with a mixture of fuming 

 nitric acid and potassium chlorate. Still one trace of graphitic 

 oxide, left as a residue, bears witness to the existence of a trace 

 of graphite, as in the case of acetylene. 



This test is not always successful. Sometimes the explosion 

 of the fulminate takes place without precipitating the carbon of 

 the cyanogen. 



Nitro-diazobenzene, which was also tested by using it as 

 a detonator instead of fulminate, decomposed without causing 

 the cyanogen to explode. Even the mode of decomposition of 



1 " Annales de Chimie et de Physique," 5* seVie, torn. xix. p. 418. The 

 voltaic arc produces a more complete transformation; but then the effects 

 of the heat become complicated by those of electricity (p. 419). 



