861^ M. Dessaignes on Malonic Acid, 



istence of lipic acid, has found among them an acid containing 

 18 equivalents of carbon. This acid is identical with Buckton's 

 acid, with whose results, however, Wirz was unacquainted. The 

 material for the investigation was obtained by acting on about 

 five pounds of the fatty acids from cocoa-nut oil with nitric acid 

 at the boiling temperature ; at the end of two months the action 

 was terminated, and the mass in the retort solidified to a cry- 

 stalline mass. On treating this with water, it separated into a 

 fatty mass which floated on the surface ; a yellowish, thick, oily 

 body, heavier than water, and which on further investigation 

 proved to be a mixture of nitrocapric and nitrocaprylic acids, 

 and an aqueous solution containing five or six acids, M'hosc sepa- 

 ration was efieeted by fractional crystallization. 



The crystals which first separate are generally considered to 

 be suberic acid. But an analysis of the silver salt showed that 

 a higher acid was present; and on recrystallization it was found 

 to contain, besides suberic acid, C^^H''*0^, an acid which gave 

 on analysis numbers agreeing with the formula C^^ IP*^ 0^. The 

 description of the properties of this acid, which Wirz names 

 lepargylic acid, leave no doubt that it is identical with Buckton^s 

 anchoic acid. Wirz analysed also the silver and lead salts. 



In the mother-liquor from these acids Wirz found pimelic 

 acid, Ci"* W 0^ and adipic acid, C^^ H'" 0*^ ; and besides these 

 he was enabled to confirm the existence of Laurent's lipic acid. 

 This acid difi'ers in many respects from the rest of the series. 

 It crystallizes from water in transparent crusts formed of ag- 

 gregated small hard nodules, which again consist of minute 

 prisms. It can be sublimed after one distillation, and is then 

 obtained in the form of long brilliant needles. By repeated di- 

 stillation it is transformed, like succinic acid, into the anhydrous 

 acid. Wirz prepared and analysed several of the salts, and made 

 a comparative investigation of this acid and pyrotartaric acid, 

 which proved that they were not identical. In the last mother- 

 liquor Wirz found succinic acid, but neither the acid below this, 

 C^ H"* 0^, nor oxalic acid. 



Dessaignes has recently described* a new acid obtained in 

 small quantities by the oxidation of malic acid by bichromate of 

 potash, which is the missing term of the series, containing six 

 atoms of carbon. It appears identical with Barral's nicotic acid ; 

 but until its identity is established, Dessaignes names it malonic 

 acid. To obtain it, bichromate of potash is gradually added to 

 a weak solution of malic acid, and the action is complete when 

 about an equivalent in weight has been added. The mixture is 

 then treated with milk of lime to precipitate the chrome, and 



* Cowptes Rendus, July 12. Chemical Gazette, September 15, 1858. 



