76 IMMEDIATE PRINCIPLES OF THE TISSUES. 



generated ovaries and testes, and carcinomatous growths. It has 

 not, thus far, been found in the urine. 



Cholesterine is found only in animals, and must be formed in the 

 organism by the liver, probably. It is not, however, known from 

 what elements it is formed, nor what office it performs in the organ- 

 ism; nor how it makes its exit therefrom, except so far as it is con- 

 tained in the feces. It is, however, to be regarded as an excre- 

 mentitious product, and probably is a result of dis-assimilation of 

 the liver itself. 



2. Oleine, Margarine, and Stearine. 



These three immediate principles are combined together to form 

 the contents of the cells of adipose tissue, and the fat-globules in 

 various tissues and fluids. Each of them is composed of a fatty 

 acid in combination with a compound radical the oxide of lipyl. 

 (C 3 H 2 0.) From the latter glycerine is formed. 



1. Oleine (C 39 H 36 O 5 ) is compounded of the oxide just mentioned 

 and oleic acid. (C 36 H 33 3 .HO.) It is, therefore, the oleate of the 

 oxide of lipyl. When isolated, it maintains its fluidity at any tem- 

 perature above zero of Fahrenheit, and in it are the margarine and 

 stearine in the tissues, dissolved. 



2. Margarine is a compound of margaric acid (C 34 H 33 3 .HO) with 

 the oxide of lipyl, or is a margarate of this oxide. It becomes 

 solid at a temperature of 118 Fahr. It forms a much greater pro- 

 portion of human fat than oleine. 



3. Stearine exists in human fat, but in very small quantity. It is 

 a compound of stearic acid (C 68 H 66 5 .2HO) and the oxide of lipyl, 

 and is the stearate of this oxide. Stearine does not exist in vege- 

 tables, but is the main constituent of all solid animal fats, as sperma- 

 ceti, suet, and tallow. 



Butter contains margarine and oleine, but no stearine. The last 

 may, however, be formed in the organism from the other two prin- 

 ciples. In a dog taking butter alone for sixty-eight days, the liver 

 contained a large quantity of stearine, and very little if any oleine. 

 (Magendie.) It will be seen that two equivalents of margarine pre- 

 cisely correspond to one of stearine, with the addition of one atom 

 of oxygen. These three principles together will not, however, by 

 themselves nourish an animal, while adipose tissue will do so for a 

 time. 



Soaps are formed by boiling either margarine or oleine with 



