COMPOUNDS OF ORGANIZATION. 71 



It is difficult to determine whether there is an oily prin- 

 ciple, to which all the different kinds of oils owe their pri- 

 mary character, or whether there are as many different 

 principles as there are species of oils. The important ex- 

 periments of M. CHEVREUL " On Fatty Bodies *," coun- 

 tenance the latter opinion. The products of the saponifi- 

 cation of the different kinds of fatty bodies, exhibited pecu- 

 liar characters by which they could be recognised, varying 

 according to the substances from which they were extract- 

 ed. These products, it must be added, were the result of 

 decomposition, and their characters, consequently, convey 

 but imperfect information, concerning the natural condition 

 of the principles of animal oils. 



Fatty matter occurs in the animal system occupying very 

 different situations. In ruminating animals, it adheres 

 chiefly to the intestines ; in seals and whales, it is seated 

 under the skin; while in fishes it is chiefly found in the cells 

 of the liver, and among the muscles. In all cases, it ap- 

 pears to be a product of secretion, and to serve as a store 

 of nourishment, being most abundant, when the animal is 

 furnished with a copious supply of food, and gradually 

 diminishing in quantity as the food becomes scarcer, and 

 disappearing when, from want, a lingering death has been 

 produced. 



Animal oils may be distinguished into the following 

 kinds. 



1. Spermaceti. This substance constitutes the principal 

 part of the brain of the whale, called Physcter macrocepha- 

 lus. It is freed from the oil which accompanies it, by 

 draining and squeezing, and afterwards by the employment 

 of an alkaline lye which saponifies the remainder. It is 



* Annals of Phil, xii. p. 186, from Annales de Chimie. 



