Intelligence and Miscellaneous Articles. 379 



monia, liydrochloric acid and azote. To separate the cyanuric acid, 

 it is sufficient to treat the cooled mass, which remains in the vessel 

 in which the decomposition was performed, with a little cold water. 

 The hydi-ochl orate of ammonia dissolves in the water, and the cyan- 

 uric acid remains in the form of a white powder, which, if requisite, 

 may be purified by solution in boiling water. The following equa- 

 tion explains the reaction of the chlorine upon the urea : 



3 {O^ H* Az2 02) + 3C1 = Az + H CI -H 2H^ Az CI + C"' Az^ H^ 0«. 

 The author considers this as the most convenient process for pre- 

 paring cyanuric acid. 



Chlorohydruret [Jiydrochlorate ?] of Cyanogen. — When a current of 

 chlorine gas is passed into a solution of hydrocyanic acid, prepared 

 by Trautwein's process, a slight increase of temperature occurs after 

 the operation has been some time continued. The liquid emits a 

 very perceptible odour of chloride of cyanogen, and a vapour is formed 

 which condenses in small drops in the cold parts of the apparatus, 

 and these constitute the principal product of the reaction : to collect 

 it, a tube with chloride of calcium is to be adapted to the retort 

 which contains the hydrocyanic acid, bent at a right angle, and 

 passed .into a long-necked receiver cooled by ice. 



When the operation is finished, the receiver contains a liquid which 

 is limpid, very volatile, fumes on exposure to the air, and emits 

 a very irritating odour of chloride of cyanogen : this is impure chlo- 

 rohydruret of cyanogen. It contains hydrochloric and hydrocyanic 

 acids, from which it is freed by agitating it with two or three times 

 its volume of cold water. The stratum of liquid which separates 

 from the water is to be poured off, and submitted to a fresh distil- 

 lation, its vapour being passed through a tube containing chloride 

 of calcium. 



The chlorohydruret of cyanogen thus prepared is a colourless, very 

 fluid and corrosive liquid. It emits an odour which strongly irritates 

 the bronchia;, and especially the eyes. It boils at 68° F. Its va- 

 pour burns with a violet flame. It dissolves sensibly in water, and 

 the solution precipitates nitrate of silver white. 



When brought into contact with dry chlorine, it is entirely con- 

 verted into solid chloride of cyanogen and hydrochloric acid, C^ Az^ 

 C1*H + C1=HCH-C«A3C13. 



If this reaction takes place with some grammes of the substance, 

 the sides of the vessel will be covered the next day with fine radia- 

 ting needles, and there remains at the bottom a viscid liquid, which 

 eventually becomes a mass of large crystals of chloride of cyanogen. 



M. Wurtz states that he had some difficulty in analysing the 

 chlorohydruret of cyanogen. Tiiis will readily be conceived, wlien 

 the extreme volatility of this liquid is considered. The experiments 

 performed by tiie author led to tlie formula O' Az^ CI- H, and this 

 appears to be confirmed by the reactions which the substance un- 

 dergoes. 



Tliis substance may therefore be considered as a compound of 

 hydrocyanic acid with chloride of cyanogen, C-* Az'^ CI-, the descrip- 

 tion of which will presently be given , or it may be regarded as solid 



