in the Butter of Nutmegs. 105 



The formula for the anhydrous acid is Cog Hgy O3; hence 

 the formula for the hydrate is Cog Hjy O3 + HO. 



There are several points besides its composition, which di- 

 stinguish this hydrate from that of margaric acid, for which 

 it has hitherto been mistaken. Its melting point is very dif- 

 ferent from that of margaric acid, and it is soluble in almost 

 every proportion in hot alcohol. The soaps which it forms 

 with potash or soda dissolve with greater facility than the cor- 

 responding soaps of margaric acid ; they are also more cry- 

 stalline in their appearance. Sericic acid does not appear 

 capable of forming two classes of salts with the alkalies, that 

 is, its salts are always neutral, and the soaps may be treated 

 with water without passing into supersalts; a character pos- 

 sessed neither by stearic nor margaric acid. 



The solution of sericic acid in alcohol strongly reddens 

 litmus paper. When it is boiled with nitric acid diluted with 

 half its weight of water, a violent action ensues, and peroxide 

 of nitrogen is evolved in considerable quantity. The products 

 of the decomposition appear to be soluble in water, for the 

 acid remaining after the action had ceased vi^as found un- 

 changed ; at least the salts of barytes and silver made from 

 it possessed a composition precisely similar to that of the 

 original acid ; the melting point also remained the same. The 

 subject was not more nearly examined. 



Sericine. — The process for obtaining this substance has 

 been described at the commencement of the paper; it is the 

 solid part of the butter of nutmegs, and has been desci'ibed 

 by MM. Pelouze and Eoudet as margari7ie (margarate of the 

 oxide of glyceril). 



Sericine is a very beautiful fat (when crystallized from 

 aether), having a snow-white colour, and silky lustre. It 

 is soluble, in all proportions, in hot aether; but the greater 

 part crystallizes on cooling : in water it is quite insoluble. It 

 is not easily saponified by caustic alkaline ley of the common 

 strength, a property which distinguishes it from margarine; 

 but it is easily converted into a beautiful while soap, by melt- 

 ing it with hydrate of potash and a very small quantity of 

 water. 



For the purpose of determining witii what base sericic acid 

 is combined in sericine, the following process was adopted. 

 A (|uantity of sericine was boiled for several days with basic 

 acetate of lead. An insoluble salt of lead was thus formed 

 with the acid : the base must, therefore, have been separated. 

 A stream of hydrosulphuric acid was now passed through the 

 liquid filtered from the salt, until all the lead was precipitated. 

 Hence the liquid could now only contain the base with wliich 



