[ 75 ] 

 X. Intelligence and Miscellaneous Articles. 



ON THE COMPOSITION OF HUMAN FAT. BY DR. HEINTZ. 

 n"^HE fatty acids procured in the form of a soft mass by the decom- 

 -■- position of soap prepared with human fat, were pressed as much 

 as possible, and the residue dissolved in a third part of its weight of 

 boiling alcohol ; the mass procured by exposing this to as low a 

 temperature as possible was again pressed, and this process repeated 

 until no trace of oleic acid was to be found in the remaining solid 

 acids. This mixture of solid acids was analysed by repeated precipi- 

 tation with acetate of lead, and four different acids procured from it. 



The first of these acids, which is most readily precipitated in com- 

 bination with oxide of lead, exists only in very small quantity ; 

 from about 2\ lbs. of human fat only about 0"2 grm. were pro- 

 cured in an apparently pure state. It crystallized from the alco- 

 holic solution in small, transparent lamina; of a pearly lustre ; on 

 fusion it soUdified into peculiar scale-like crj-stals. Its melting- 

 point is at 156°, and was not raised by repeated crystallization from 

 alcohol. Its analysis led to the formula C^e H^e O*. 



Found. Calculated. 



Carbon 75-84 C^s 76-06 



Hydrogen 12-70 H^e 12-68 



Oxygen 11-46 O" 11-26 



100-00 10000 



Heintz considers it probable that this acid is identical with the 

 stearophanic acid discovered by Dr. Francis* in the berries of Coc- 

 culus indicus. 



The second acid, which, next to that above mentioned, is most 

 readily precipitated by oxide of lead, is called anthropic acid by Dr. 

 Heintz. From 2-1- lbs. of human fat only about 1 grm. of this 

 acid was procured. When pure it crystallizes from the alcoholic 

 solution in beautiful broad laminae of a pearly lustre, melts at 133°, 

 and solidifies on cooling into beautiful shining laminar crystals. 

 The alcoholic solutions of its alkaline salts solidify on cooling into 

 an opaline jelly ; earthy and metallic salts produce insoluble preci- 

 pitates in these solutions. Dr. Heintz considers the composition of 

 this acid as not yet placed beyond doubt ; his analyses gave for the 

 free acid the formula C^* H^^ O* ; for the silver salt, AgO, C3+H»'03 ; 

 for the baryta salt dried at 212°, BaO, C^^ H^' 0^ + HO. 



Free acid. Silver salt. Baiyta salt. 



, • , , « , , « ^ 



Found. Calc. Found. Calc. Found. Calc. 



C'« 75-99 76-12 C^* 53-87 54-41 C^* 59-23 59-24 



H32 12-40 11-94 H" 8-47 8-27 H^* 9-35 9-29 



O-* 11-61 11-94 O* 8-78 8-54 0* 9-03 9-29 



100^ 100^ Ag_2£88 28-78 BaO 2239 22-18 



100-00 100-00 10000 10000 



Dr. Heintz considers it possible that this acid may prove identical 



with the acid procured by Luckt from the oil of Madia aativa. 



* Phil. Mag. Ser. 3. vol. xxi. p. 161. 



t Annalen der Chemie und Pharmacie, xxxv. 210. 



