1867.] 



Homologous to Hydrocyanic Acid. 



145 



ammonia into prussic acid by means of chloroform, which was first observed 

 by M. Cloez, and which illustrates so well our present views on quantiva- 

 lence. When the two substances alone are allowed to act upon one another, 

 this reaction can be rapidly accomplished only at a high temperature and 

 consequently under pressure. In order to shorten the process (in one word, 

 in order to exhibit this important reaction in a lecture-experiment), I had 

 added potash, to the mixture for the purpose of fixing the newly formed 

 prussic acid, and was delighted to find that a few seconds' ebullition was 

 sufiicient to yield a considerable amount of cyanide of potassium, so as to 

 furnish, after the addition of the two salts of iron, a large quantity of Prus- 

 sian blue. On subsequently repeating the experiment with som.e of the de- 

 rivatives of ammonia, more especially with several primary monamines, I 

 was astonished to observe in each case a powerful reaction giving rise to the 

 evolution of vapours of an almost overwhelming odour, strongly recalling 

 that of prussic acid. But few experiments were necessary for the purpose 

 of isolating the odoriferous bodies. The compounds thus formed are the 

 substances isomeric with the hydrocyanic ethers or nitriles hitherto ex- 

 amined. 



From the host of bodies which were thus suddenly thrown into view, it 

 was necessary to single out the compound of a particular series in order to 

 determine by accurate experiments the nature of the new reaction. The 

 facility of procuring the necessary material, as well as old predilections, 

 suggested the phenyl-series as the one to be examined in the first place. 

 I beg leave to submit to the Royal Society a brief account of the mode of 

 preparation, and of the principal properties, of the new derivative of aniline. 



Cyanide of Phenyl, 

 A mixture of aniline, chloroform, and alcoholic potash yields on distillation 

 a liquid of a powerfully aromatic but, at the same time, hj-drocyanic-acid- 

 like odour. The vapour of the liquid gives rise to a peculiar bitter taste, 

 and causes, moreover, in the throat the suffocating sensation so characteristic 

 of hydrocyanic acid. On redistilling the liquid, alcohol and water pass 

 first, and ultimately an oily body is procured, which, in addition to the 

 smelling substance, still contains a large amount of aniline. The latter is 

 separated by oxalic acid, when the powerfully smelling compound remains 

 in the form of a brownish oil. Freed from water by hydrate of potassium 

 and purified by distillation, the new body presents itself as a mobile liquid, 

 exhibiting a greenish colour in transmitted, and a beautifully blue colour 

 in reflected light. This colour does not disappear by distillation even in a 

 current of hydrogen. 



The analysis of the blue oil has established the formula 



C,H,N. 



The compound is thus seen to be isomeric with benzonitrile, discovered by 

 Fehling, from which it differs, however, in all its properties. In order to 

 distinguish the new compound from benzonitrile I will call it cyanide of 



