. 



DRY DISTILLATION OF MARGARIC AND STEARIC ACIDS. 981 



entirely into bistearate. The solutions of the stearates of alka- 

 line bases are precipitated by salts of all the other metallic 

 oxides, insoluble stearates being formed. 



Stearine, or the acid stearate of oxide of glyceryl is the 

 essential part of all kinds of suet ; it may be obtained by fusing 

 purified mutton suet by a water bath, dissolving it in 8 or 10 

 times its .volume of ether, allowing the solution to cool, which 

 becomes a thick mass, and washing the expressed solid matter 

 with ether. It forms white pearly plates, fuses at 140 or 143.6 

 (60 or 62 centig.), and on cooling again forms a solid pulve- 

 risable mass which is not crystalline. It dissolves in 6 or / 

 parts of boiling alcohol. This stearate in combination with the 

 oleate of glyceryl forms the solid portion of the butter of cacao. 

 According to the analysis of Liebig and Pelouze, stearine may 

 be represented by C 6 H 7 O 5 .HO,C 68 H 66 O 5 -f HO, or by 1 atom 

 of hypomargarylic acid combined with 1 atom of oxide of 

 glyceryl and 1 atom of water as bases, with an additional atom 

 of water of crystallization. 



PRODUCTS OF THE DRY DISTILLATION OF MARGARIC AND 

 STEARIC ACIDS. 



Stearic acid distilled in a vessel about two thirds filled with 

 the acid, yields first a white solid product, which fixes at 156.2 

 (6.9 centig.), and is a mixture of margaric acid fusible at 140, 

 of a crystalline neutral body margarone fusible at 170.6, and 

 of a liquid hydrocarbon in small quantity. The last half of the 

 distilled product is generally softer and accompanied with in- 

 flammable gases ; and towards the end the residue blackens 

 and assumes the consistence of tar. When stearic acid is 

 distilled with one fourth of its weight of quicklime, a soft buttery 

 mass is obtained, consisting in a great measure of the liquid 

 hydrocarbon and margarone. The products of the distillation 

 of margaric acid are similar. (Redtenbacher and Varrentrapp.) 



Margarone) C 33 H 33 O, was discovered by Bussy. It is formed 

 by the dry distillation of margaric and stearic acids alone or 

 mixed with quicklime ; it may be freed from adhering margaric 

 acid by caustic ley in which margarone is insoluble, and purified 

 by crystallization from alcohol. It is a white very friable 

 pearly mass, and becomes electrical by friction. It is volatilised 



2 11 u 



