Intelligence a7id Miscellaneous Articles. 77 



In every point of view, whether as regards the just claims of Sir 

 John Herschel on the regard of every lover of science, or the claims 

 of science itself on the estimation of the public, the Herschel Dinner 

 must be considered as one of the most interesting and successful 

 meetings ever held to promote the triumphs of intellect and social 

 virtue. It is with great satisfaction that we have understood that 

 the rank of a Baronet of the United Kingdom has since been con- 

 ferred upon the illustrious object of this festival. 



ACTION OF LIGHT ON SOLUTION OF CYANOGEN. 



MM. Pelouze and Richardson have read a memoir on this subject 

 to the Institute, in which they observe that the knowledge which 

 chemistry possesses on the above-named subject is very incomplete. 

 M. Vauquelin was occupied with it in 1818, and showed, that besides 

 ammonia and a peculiar black substance, there were formed by the 

 action of cyanogen upon the elements of water, three distinct acids, 

 namely, carbonic and hydrocyanic acids, and another which he con- 

 sidered as composed of cyanogen and oxygen. His opinion as to the 

 nature of this last substance was entirely founded on theoretic views, 

 for he had not separated his new acid, nor studied any of its combi- 

 nations. The experiments of MM. Pelouze and Richardson show 

 that M. Vauquelin was in error in announcing the formation of 

 cyanic acid by the decomposition of cyanogen in water, and the 

 substance which he supposed to be cyanate of ammonia was a mix- 

 ture of urea and oxalate of ammonia. 



An aqueous solution of cyanogen, prepared in the usual manner, 

 was exposed to the action of light, until the odour of cyanogen ceased. 

 The solution had a strong smell of hydrocyanic acid ; its colour was 

 slightly yellowish, and it was neutral. In the lower part of it a 

 light, black, flocky substance was separated. It was collected in a 

 filter, and freed by distilled water from foreign soluble matter. After 

 this purification it was but slightly soluble in water and in alcohol, 

 insoluble in aether, but on the contrary dissolved by acetic acid and 

 the caustic alkalis, and with bases it formed true salts. 



The authors had not so much of this substance to subject to 

 analysis as they could have wished, but they are of opinion that its 

 true composition is expressed by the formula Az« C^ H'< O**. 



Part of the liquor was submitted to ebullition, and the vapour dis- 

 engaged was passed into lime-water. An abundant precipitate of 

 carbonate of lime was formed, which left no doubt as to the formation 

 of carbonic acid during the decomposition of cyanogen in water. 

 The remainder of the liquor jdelded during concentration a very 

 sensible quantity of ammonia and hydrocyanic acid. The dried 

 residue had a distinct yellow tint, and a sharp saline taste. Put 

 into alcohol it was divided into nearly equal portions ; the soluble 

 portion possessed all the characters of urea ; the residue insoluble in 

 alcohol was oxalate of ammonia. 



The authors state that the analysis and minute examination of 



• In this notice the original formulae are preserved. 



