158 OILS AND FATS. [VI. 



Caproic C^^H^^O^ 



Capryllic C^eH^gO^ 



Capric C^cH^qO^ 



Pichuric (lauric, laurostearic) Cg^Hg^O^ 



Myristic (probably) C^gH^^O^ 



Palmitic Cg.Hg^O^ 



The cocinic acid of St. Evre is a mixture of capric and 

 pichuric acids. 



Stearic Acid. — Gerhardt and Laurent have endeavored to 

 prove (Comptes Rendus, 1849) that the formula for stearic 

 acid is Cg^Og^O^ ; that margaric acid is an isomeric modification 

 of it, and should be called metastearic acid. 



Oil of the Beaked Whale. — The train-oil of the lalsena 

 rostrata has recently been examined by Scharling (Journ. f. 

 Prac. Chem. xliii.), who gives it the formula Cg^Hg^O^. It 

 consists principally of a liquid fat, free from glycerin, a minute 

 portion of spermaceti and traces of other fats. Its spec. grav. 

 is .8807 at 52°. It burns with a bright flame, and its illu- 

 minating power is in the ratio of 1.57 : 1 of common whale 

 oil. It also burns slower and emits less smoke than the latter 

 oil. 



Bleaching of Oil hy Cliromic Acid. — Mr. C. Watt, Sr. 

 (Newton's Journ. 1848, and Ch. Gaz. vi.), uses the following 

 method for bleaching dark oils or tallow. To every | ton of oil 

 take lOfb bichromate of potassa. Powder the salt, dissolve it 

 in 4 pts. hot water, stir, and carefully add 15ft) sulphuric acid, 

 and continue the stirring until complete solution. This mix- 

 ture is then thoroughly incorporated with the melted fat, 

 previously separated from foreign matters by repose and de- 

 cantation. The containing vessels should be of wood, and the 

 temperature about 130° F. When, after much agitation, the 

 liquid fat assumes a light-green color, the bleaching is com- 

 pleted, and 4 buckets of boiling water are then to be added, the 

 whole stirred for five minutes and then left to repose for 

 several hours, when it will be white and ready for use. 



Mr. Watts, Jr., proposes to recover the chromic acid ad 

 infinitum^ and thus render the process very economical, in 



