APPENDIX 335 



degrees; and as they begin to yield to the influence of this high temperature, 

 or the remaining oil begins to soften the cakes, they are taken and shaved 

 into very fine pieces, or ground up as in some instances, deposited in bags as 

 hitherto, and put into the hydraulic press. 



The room being at the temperature indicated above, and the bags sub- 

 jected to a powerful pressure of three hundred tons or more, all the oil is 

 extracted from them, and what is left is perfectly dry, free from any oily 

 matter, and brittle. The oil thus obtained by this last pressing is called 

 tight -pressed, or summer oil. 



Spermaceti. What remains after the several pressings, and the removal of 

 all the oil, is called stearine, or sfermaceti. 



Spermaceti is not confined to the head matter of the whale, as some sup- 

 pose . . . But . . . the spermaceti from the head oil is quite difl"erent 

 from that of the body oil; the former presents fine, bright, transparent 

 scales like small particles of isinglass, while the latter is more compact, some- 

 thing like dough. In cooling, one exhibits a sparry, crystalline structure, the 

 other that of clay. 



Head oil or matter is usually manufactured with the body oil of the whale, 

 and mixed in proportion to one-third of the former to two-thirds of the latter. 



Spermaceti Candles. That which remains in the bags after the hydraulic 

 pressure is both dry and brittle. The oil, it is supposed, is wholly extracted, 

 and nothing now remains but the spermaceti. Its color, however, is not 

 white, but interspersed with grayish streaks, bordering on the yellow. 



The spermaceti is put into large boilers adapted for the purpose, and 

 heated to the temperature of two hundred and ten degrees. It is refined 

 and cleared of all foreign ingredients by the application of alkali. After- 

 wards water is added, which, with a temperature of two hundred and forty 

 degrees, throws off the alkali in the form of vapor. The liquid which re- 

 marns is as pure and clear as the crystal water, and ready to be made into 

 the finest spermaceti candles. 



