238 [Recess, 



analysed the silver-salt of this acid, and obtained results establishing 

 the formula C H 



13 



This acid forms nearly colourless crystals, which are very soluble 

 in water, alcohol, and ether. They have an agreeable acid taste. 

 The free acid gives an abundant precipitate with acetate of lead, 

 soluble in strong acetic acid. The neutralized acid forms with per- 

 chloride of iron a reddish-brown precipitate, from which the acid 

 can be partially removed by solution of ammonia. Neither chloride 

 of barium nor chloride of calcium affects the neutralized acid. An 

 abundant precipitate, however, makes its appearance on the addition 

 of alcohol to the mixed solutions. These reactions resemble those 

 of succinic acid. It is, however, readily distinguished from that acid 

 by its behaviour when exposed to heat. Thus it melts when exposed 

 to the temperature of about 158 Cent., and when subjected to a 

 higher temperature suffers decomposition. 



In order to satisfy myself that the nitric acid employed in the 

 process I have just described does not play a part in the reaction 

 which generates the new body, as is necessary if the equation given 

 at the commencement of this paper is correct, I have endeavoured to 

 prepare it without the aid of that acid. In this I have succeeded, 

 the body formed being identical in properties and composition with 

 that obtained by the first method. 



That this acid is tribasic, we cannot well doubt, if we take into 

 consideration the manner of its formation, and the composition of its 

 silver-salt. Nevertheless I will endeavour, by the examination of 

 several salts, to obtain further evidence on this point. 



I regret to say I have not yet succeeded in rendering the tercyanide 

 of allyle sufficiently pure for analysis. On evaporating the alcohol, 

 in the midst of which the terbromide of allyle and cyanide of potassium 

 have reacted, a black mass is obtained exactly like tar in colour and 

 consistence. This I partially purified by solution in ether. On 

 evaporating the ether a brown liquid is left, which is very soluble in 

 water. 



This gave, when gently heated with sodium, cyanide of sodium. 

 When treated with potash, it yielded an organic acid and ammoniacal 

 gas. With muriatic acid it gave an organic acid also, no doubt the 

 same, and muriate of ammonia. These three reactions, coupled with 



