SERICIC AND PALMITIC ACIDS. 957 



Sericic or Myristic acid, HO + C 28 H 26 O 3 (Playfair). This 

 acid is obtained from the solid portion of the butter of nutmegs, 

 the fruit of Myristica moschata, in which it is combined with 

 glycerine. This solid portion dissolves completely in 4 parts of 

 boiling alcohol, by which it may be easily distinguished from 

 other soluble fat bodies, and gives, on the cooling of the liquid, 

 the sericate of glyceryl in thin silky needles. 



Sericic acid, which was discovered by Dr. Playfair, crystallizes 

 in white brilliant plates, of a silky lustre, (hence the name, 

 sericic acid) ; it fuses between 118.4, and I20.2 (48 and 49 

 centig.), and on cooling becomes a mass, having a very distinct 

 crystalline structure. It is very soluble in alcohol and ether, 

 insoluble in water. It is decomposed by dry distillation, and 

 violently attacked by nitric acid. Sericates of alkaline bases 

 are distinguished from other soaps by crystallizing from alcohol ; 

 their solutions do not become viscid and thready by concentra- 

 tion, nor are they disturbed by the addition of much water 

 (Playfair). Sericic ether is an oily, colourless liquid, of density 

 0.864. Sericine, or sericate of glyceryl, contains as base oxide of 

 glyceryl minus 2HO, orC 6 H 5 O 3 ; its formula being C 118 H 113 O 15 

 =4 (C 2 sH 27 3 ). 



Palmitic acid, HO -f C 22 H 31 O 3 (Fremy, Stenhouse). A soap 

 of the palm oil of commerce yields when decomposed by an 

 acid, a mixture of palmitic and oleic acids; which mixture, dis- 

 solved in boiling alcohol, gives crystals of palmitic acid on 

 cooling. Purified by repeated crystallization from alcohol, pal- 

 mitic acid forms brilliant plates, which completely resemble 

 those of margaric acid, and have the same point effusion, 140 ; 

 it is insoluble in water. It dissolves in alkaline carbonates, and 

 forms a transparent emulsion. After being heated to 572 

 (300 centig.), palmitic acid does not crystallize from alcohol in 

 leaflets, but in mammillated masses, which, however, have pre- 

 cisely the same composition (Fremy). Palmitic acid distils with 

 very little alteration. Chlorine decomposes the acid when 

 heated, and yields several chlorinated products, which are less 

 fluid, and acid, but do not combine with bases without losing 

 their chlorine. Palmitate of glyceryl or palmitinc, when pure is 

 crystalline, and of brilliant whiteness, is very slightly soluble in 

 boiling alcohol, but dissolves in boiling ether in all proportions, 

 and is deposited, on cooling, in extremely small crystals. From 

 the analysis of Dr. Stenhouse, palmitine is represented by 



