138 OILY OXIDES, SAPONIFIABLE. 



gealed into a mass in which might be distinguished a white so- 

 lid matter and a yellow oil. Another specimen from the thigh 

 continued quite fluid at 59. When kept for some days at that 

 temperature in a close flask it deposited a solid matter ; but af- 

 ter an interval of a fortnight it was still partly liquid, a yellow 

 oil floating on the solid portion. These variations in the congeal- 

 ing point depend upon a variation in the proportion of the stearin 

 and elain in this fat. 



Human fat is soluble in 40 times its weight of hot alcohol of 

 0-821. On cooling the liquid deposites stearin, which, after be- 

 ing again dissolved in hot alcohol and deposited, and exposed to 

 pressure between the folds of blotting-paper, possesses the follow- 

 ing properties : It is colourless, has little lustre, and melts at 

 122. It may be cooled down to 106 before it begins to con- 

 geal, but the instant congelation begins the heat rises to 120. 

 The stearin crystallizes in a mass composed of small needles. 

 One hundred parts of boiling absolute alcohol dissolve 21*5 of 

 this stearin. But the greatest part precipitates when the solu- 

 tion cools. The elain is a colourless oil which remains liquid 

 though cooled down to 25, but congeals into needles at a few 

 degrees below that temperature. Its specific gravity at 59 is 

 0'913. It has no smell but a sweetish taste. One hundred 

 parts of boiling alcohol dissolve 123 of this elain, and the solu- 

 tion becomes muddy when cooled down to 170^. 



One hundred parts of human fat when saponified yield, 

 Margaric and oleic acids, 95 '24 to 96*18 

 Glycerin, . . 9-66 to 10 



The mixture of margaric and oleic acids melt between 88 and 

 95. The stearin gives 8 '6 of glycerin with 94'9 of fatty acids, 

 in which there is no stearic acid, and which melt at 124. The 

 elain gives 9 '8 of glycerin and 95 of fatty acids fusible at be- 

 tween 93 and 95. 



Fourcroy described under the name of adipocirin, a fat obtain- 

 ed from dead bodies which had been long piled up together, and 

 which he considered a combination of a peculiar fatty matter with 

 ammonia. Chevreul has shown that it is merely human fat sa- 

 ponified (doubtless by ammonia) ; and of course a combination 

 of margaric and oleic acids with ammonia. 



6. GOOSE FAT. 



It is colourless, and has a peculiar taste and smell, rather agree- 



