196 M. Chevreul on Fatty Bodies, and [Sept. 



For the purpose of analyzing the soap, it was added to a large 

 quantity of water, and kept at the temperature of 212°; it was 

 not dissolved ; but the fluid, as it cooled, deposited a large quan- 

 tity of opaque flakes. A portion was kept suspended, which 

 had a brilliant and pearl-like appearance ; this was collected, 

 and dissolved in boiling alcohol, from which it was in part depo- 

 sited by the cooling of the fluid : this was the proper soap 

 formed of spermaceti and potash. This soap, after being 

 properly purified, was decomposed by muriatic acid, when it was 

 found to be composed of a peculiar fatty substance, to which 

 M. Chevreul gives the name of saponified spermaceti and potash, 

 in the following proportions : 



1 Saponified spermaceti. . . 92-462 100-00 



Potash 7-538 8-15 



The soap of spermaceti is white, and is without taste. Alco- 

 hol, which has been saturated with it at the boiling heat, 

 concretes into a mass as it cools ; the solution slightly reddens 

 hematine, but has no action upon litmus, in which respect it 

 differs considerably from the super-soap of margarine. The soap 

 of spermaceti is insoluble in water; but if it be boiled for a long 

 time in this fluid, a quantity of the alkali is separated from it. 

 The soap itself, by this process, appears to be decomposed into 

 two compounds containing different proportions of potash ; one, 

 5*48 parts of potash ; and the other, four parts to 100 parts of the 

 saponified spermaceti. 



M. Chevreul then examined the properties of the saponified 

 spermaceti ; its melting point is the same with pure spermaceti, 

 but it is more soluble in alcohol ; the solution reddens litmus ; 

 and, as it cools, concretes into a crystalline mass ; it is capable 

 of being combined with an additional quantity of potash, so as 

 to form a soap similar to that described above. The author next 

 enters into a minute analysis of the substances which are con- 

 nected with the saponified spermaceti in the process by which it 

 is formed ; he supposes them to be as follows : 1 . Saponified 

 spermaceti ; 2. An oil which is fluid at the ordinary temperature 

 of the atmosphere ; 3. A concrete oily substance; 4. A yellow 

 matter ; and, 5. A volatile oil : but it is admitted that the last 

 four bodies exist in so small quantity as to render it difficult to 

 ascertain their properties with accuracy. It is supposed that the 

 third substance is a combination of the first two ; and that it is 

 particularly to the second that" it owes its property of being 

 soluble in potash. M. Chevreul remarks that the air may have 

 had some effect upon these substances, particularly upon 

 the fourth and fifth ; for that the experiments occupied more 

 than six months, during which time they were continually 

 exposed to the air. Saponified spermaceti is very analogous to 

 margarine ; but this substance is sufficiently distinct from sper- 



