294 DIAZO-COMPOUNDS. 



i.e. with a low density of charge, the composition of these gases 

 was as follows : 



HCN 

 CO 

 CH 4 

 H 



N 



3-2 or, for 136-6 litres . 4-4 



48-65 . 66-4 



2-15 . 2-9 



27-7 . 37-9 



18-3 . 25-0 



100-0 136-6 



It may be observed in this explosive decomposition 

 (a) That a considerable quantity of hydrocyanic acid is 

 formed. 



(&) That the whole of the oxygen, to within about one-hun- 

 dredth, is found as carbon monoxide ; i.e. the carbon takes up 

 all the oxygen, while water is not formed to any appreciable 

 extent in the detonation. 



(c) That only three quarters of the nitrogen is disengaged in a 

 free state, one-fifteenth being given off as hydrocyanic acid. The 

 remainder is contained in the carbonaceous products of the ex- 

 plosion; a fraction, however about one-fifth of the surplus 

 nitrogen is found condensed as ammonia, as will be shown pre- 

 sently ; but, all allowance being made, the greater part (about 

 half an equivalent) remains united with the carbon, under the 

 form of a special fixed nitrogenous compound. 



(d) That the free hydrogen amounts to almost three and a half 

 equivalents out of the five equivalents that the substance con- 

 tained ; one half equivalent goes to form marsh gas, another 

 half equivalent goes to form ammonia and hydrocyanic acid, and 

 the last half equivalent remains united with the carbon. 



(e) That exactly half the carbon forms carbon monoxide. A 

 ninth of the remainder goes to form hydrocyanic acid and marsh 

 gas. 



(/) That the solid residue contains nearly half (|) its weight 

 of carbon. A ninth of the remainder enters into the acid and 

 marsh gas. The gross composition of the residue approximates 

 pretty closely to the proportions represented by C 5 H 2 N 2 ; it is 

 therefore a carbon rich in nitrogen and hydrogen, combined 

 under the form of condensed and polymerised bodies of the 

 paracyanogen type. 



(g) That the gaseous products comprise, according to the 

 calculation of the preceding analyses, 75*9 per cent., by weight, 

 of the substance. A direct experiment effected by observing 

 the loss of weight of the apparatus when the gases are allowed 

 to escape freely after the explosion, gave 75*6. 



(Ti) That, therefore, the solid residue comprises 241 per cent, 

 by weight. It exists as charcoal reduced to an impalpable 

 powder which is very voluminous and emits an ammoniacal 

 odour. The quantitative analysis of free ammonia in the 



