72 PHILOSOPHY OF ZOOLOGY. 
then washed in water, cut into thin pieces with a wooden 
knife, and exposed to the air to dry. 
It is usually im the form of glossy white flakes, semi- 
transparent and friable. It melts at 112°, and may be dis- 
tilled without experiencing great change. About 150 parts 
of boiling alcohol dissolve 1 of spermaceti, which is ‘again 
deposited as the solution cools. 
It is used in medicine, and in the arts to make candles. 
2. Ambergrease.—This substance is of a whitish colour, 
brittle, adheres like wax to the edge of the knife with 
which it is scraped. Its specific gravity varies from 780 
to 926. At 122° it melts, and at 212° it is volatilized. It 
is insoluble in water. Alcohol, and the volatile oils, dis- 
solve it. With alkalies it forms a soap soluble in water. 
According to Bourtton LA GRaNcE, it 1s composed of 
52.7 Adipocere, 
s 30.8 Rezin, 
5.4 Charcoal. 
It is found in the intestines of the spermaceti whale, and 
in those only which are in a sickly state. It appears to be 
the excrement altered by leng retention in the intestines, 
and therefore scarcely merits a place among the natural in- 
eredients of the animal system. Upon being voided by the 
animal, it floats on the surface of the sea, and has been 
found in various quarters of the globe. It usually contains 
the beaks of cuttle-fish adhering to it. 
It is employed in small quantities by druggists and per- 
fumers. 
3. Fat.—Fat is usually purified by separating the vessels 
and membranes which adhere to it, by repeatedly washing 
with cold water, and afterwards melting it along with boil- 
ing water. Still, however, it consists of two substances, 
suet and oil. Cuevreun attempted to separate them, by 
