1862.] 237 



the same reagent tribasic acids, containing six equivalents of carbon 

 more than the original radicals. Thus, as we obtain in this way from 

 cyanide of ethylene (to take a particular case) a bibasic acid of the 

 composition C 8 H 6 O 8 (succinic acid), so from the tercyanide of 

 allyle (C 6 H 5 Cy 3 ), if the analogy holds good, one ought to get a tri- 

 basic acid having the composition C 12 H 8 O 12 : 



O 4 +2NH 3 



O 6 + 3 NH 3 



The following experiments were performed with the view of deter- 

 mining this point. 



One equivalent of terbromide of allyle (C 6 H 3 Br 3 ) and three equi- 

 valents of pure cyanide of potassium were made to react upon each 

 other, by exposing them, with the addition of a considerable quantity 

 of alcohol, to the temperature of a water-bath in well-corked soda- 

 water bottles. After 1 6 hours' heating, I found that almost all the 

 cyanide of potassium had been converted into bromide. I then 

 separated the alcohol, which I assume contained impure tercyanide 

 of allyle in solution, and introduced it together with a quantity of 

 solid potash into a large balloon. To this a reversed Liebig's con- 

 denser was attached, and heat applied by means of a water-bath, 

 which occasioned the evolution of a large quantity of ammoniacal 

 gas. As soon as the disengagement of this gas had ceased, the 

 alcohol was distilled off, and the residue cautiously treated with 

 nitric acid in excess. This liberates an organic acid from the potash, 

 and at the same time partially destroys a black tarry matter which 

 is present in large quantity. The whole was evaporated to dryness 

 at a low temperature, and the dry mass treated with alcohol, which 

 dissolves the free organic acid, but not the nitrate of potash which 

 accompanies it. The residue obtained on evaporating the alcohol 

 was then neutralized by ammonia, and precipitated by nitrate of 

 silver. Finally, the acid was separated from the silver-salt by 

 sulphuretted hydrogen, and twice crystallized from water. The 

 crystals gave on analysis numbers agreeing very well with the 

 formula C 12 H 8 12 . I obtained 41*24 per cent, carbon and 4'82 

 hydrogen, instead of 40'91 carbon and 4*54 hydrogen. I have also 



