ACIDS OF CASTOR OIL. 96? 



considerably resembling benzole acid. This acid is insoluble in 

 water, sparingly soluble in ether, but highly soluble in alcohol, 

 particularly when hot ; the alcoholic solution reddens litmus 

 strongly. Elaidic acid appears to distil without change. It 

 decomposes alkaline carbonates and forms salts which dissolve 

 in 6 or 8 parts of water, producing a transparent very thick 

 emulsion. These salts may be crystallized from alcohol. 



Oleic acid, when treated with nitric acid, gives rise to a series 

 of acid products, discovered by Laurent, many of whose results 

 have since been confirmed by Bromeis. These are, in addition 

 to suberic acid, azelaic acid, HO + C 10 H 8 O 4 , an acid isomeric 

 with suberic acid, and closely resembling it; pimelic acid, HO 

 -f-C 7 H 5 O 3 , which crystallizes in white hard grains; adipic acid, 

 HO + C 6 H 4 O 3 (Laurent), or 2HO + C 14 H 9 O 7 (Bromeis); lipic 

 acid, when crystallized, HO -|-C 5 H 3 O 4 , when sublimed C 5 H 3 O 4 ; 

 azoleic acid, C 13 H 13 O 4 . 



When oleic or elaidic acid is heated to dryness in a silver 

 capsule with three times its bulk of strong potash ley, the mass 

 being continually stirred till it becomes dry, and heated till the 

 potash begins to fuse, the materials swell considerably, and 

 much hydrogen gas is evolved. The yellowish-brown saline 

 mass contains a new fat acid, besides much acetic acid. This 

 acid, which is the same from both oleic and elaidic acid, crys- 

 tallizes when separated in thin needles of brilliant whiteness, 

 fusible at ]4,S.6 (62 centig.). It has been studied by M. Var- 

 rentrapp, who represents it by HO-rC 32 H 30 O 3 ; which differs 

 only from palmitic and ethalic acids by containing an atom less 

 of hydrogen* 



ACIDS OF CASTOR OIL. 



Castor oil differs considerably from the other fixed oils, par- 

 ticularly by its solubility in alcohol. A soap of this oil, when 

 decomposed by a mineral acid gives a solid and a liquid oily 

 acid. The first is termed margaritic acid by Bussy and Lecanu ; 

 it fuses at 266; the second is named ricinic acid. 



Nitric acid gives with castor oil an acid, named cenant/iylic 

 acid by Mr. Tilley, from its relation in oenanthic acid. The 

 formula of oenanthylic acid is HO + C 14 H 13 O 3 (Tilley). Ac- 



