OR, A TREATISE ON PILE. 45 
bile ; one of which, found in the bile of the ox, is of a brownish-green color.* We know 
that long continuance in the dark will bleach vegetables, which were previously colored; 
and we have the authority of Rayer, (in Diseases of the Skin, p. 337,) for saying that it 
will have the same effect upon hair. Should we feel disposed, in accordance with this 
reasoning, to attribute the colors of hair to chromule, it will not be necessary to say with 
Berzelius, that there are three kinds of it; for we know that, in the inorganic world, di/ferent 
colors are displayed by the same matter, according to the different degrees of oxygen and 
light that are present. For instance, a piece of iron, by merely heating it, (1. e. by 
causing it to absorb oxygen and generate light,) becomes first yellow, then red and finally 
white, colors which are all found in pile. A writer in the Boston Journal of Science, 
(v. 1, p. 97,) says that he mixed lime, alumine, silica, soda and _boracie acid, and upon 
exposing the compound to a strong heat, had a white product; this he ground and sub- 
mitted to a red heat, when it turned of that color; upon increasing the heat it became 
white again. These changes were produced by heat and light. Chlorophyl has been 
found to be a coloring material of some of the lower animals of a green color.t 
From the whole of the above we may fairly infer that chlorophy] is not restricted to any 
form of matter, but belongs, in common, to inorganic and organic, to the animal as well as 
the vegetable commonwealth. Vegetables borrow it from minerals and loan it to animals. 
We every day appropriate a quantity of it in our food, one portion colors the blood, another 
the bile, and a third dyes the hair.t A large quantity is not required, for, according to 
_ Berzelius, it is so potent that all the foliage of a large tree contains but ten grains! If it 
should be objected that the analogy between vegetable matter and pile is imperfect, inas- 
much as vegetables have various secreting organs, corresponding with the different colors, 
while a perfect hair has but one, we would answer that all the coloring matter, however 
various the tints, of the shell of a mollusc, is deposited by the same mantle. 
If we are correct in supposing that the variegated colors of the golden mole, (Chryso- 
chloris,) are caused by the polarization of light, that which is called white hair is merely 
colorless, and black hair is opaque, the tints of hair are reduced to three; and, what is 
remarkable, these three belong to the modifications of the three colors the least dispersed of 
the solar spectrum, viz: red, orange and yellow.§ It is, therefore, not unphilosophical to 
* If to the fluid which contains the yellow coloring matter of bile, we gradually add nitric acid, it turns first blue, then 
green, then violet, then red, and then yellow or yellowish-brown. 
+ See the remarks on the green monkey. 
+ Bakewell says that in some parts of Gloucestershire the wool acquires an orange color, in Hertfordshire and Warwick- 
shire it i$ of a brownish red, and in the fens of Lincoln and Cambridge, a dark blue tint; each corresponding with the color 
of the soil. (Essay on Sheep, p. 31.) 
@ The color of what is called the green monkey is a modification of yellow. Mr. Bennit says, the color is greenish- 
yellow above, arising from the ringing of the hairs with various shades of yellow and black, but assumes more of a dark 
grizzled appearance on the sides of the body, and outer sides of the limbs, which become gradually darker towards the 
hands. The face, ears, and naked part of the hand are jet black; the former is of a triangular shape, bounded above the 
eyes by a straight line of stiff black hairs, and on the sides by spreading tufts of light hairs with a yellowish tinge, meeting, 
in a point, beneath the chin. The neck and chest are white; the under parts of the body have a yellowish tinge; and the 
inside of the limbs are grey. (See Nat. Lib. Mam., y. 1, Monkeys, p. 141.) We also read of the blue goat of the Cape 
of Good Hope. (See Gold. Hist. of Man, &e., 260.) 
