ADIPOSE TISSUE. 
189 
cularly. It is a crystalline substance, of a white or 
yellowish white colour, which is deposited in the large 
cranial cells or interspaces of the Spermaceti Whale . 
During the life of the animal it is liquid, but it readily 
crystallizes and separates after death. It was formerly 
considered useless, and hundreds of tons have been 
thrown into the Thames, but it is now largely em- 
ployed in the manufacture of candles, and is even 
more valuable than the oil itself, from which it separates 
in flaky crystals. When spermaceti is exposed to a 
heat of 115° Fahrenheit, it melts, and again crystallizes 
on cooling; in this condition it has the property of 
polarizing light, and exhibits a beautiful series of colours. 
The same power of polarizing light is also possessed by 
a substance somewhat like spermaceti, produced by the 
decomposition of certain animal tissues, especially the 
muscular, and known by the name of adipocire. A fine 
specimen of this material, formed from the thigh of a 
man by the action of water, is preserved in the College 
Museum. Like spermaceti, adipocire is easily melted, 
and crystallizes on cooling. 
I have already stated that the cells are arranged in 
lobules, and that each lobule is invested by areolar tissue, 
which passes among the cells, and gives support to the 
blood-vessels. The blood-vessels rapidly divide into a 
capillary network, which not only surrounds the individual 
lobules, but branches in the form of loops encircle each fat- 
cell. These capillary loops are represented, in Fig. 143, 
under a magnifying power of two hundred and fifty 
