OR, A TREATISE ON T PILE. 45 



bile ; oae 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 w r e feel disposed, in accordance with this 

 reasoning, to attribute the colors if hair to chromule, it will not be necessary to say with 

 Berzclius, that there are three kinds of it; for we know that, in the inorganic world, different 

 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, (i. 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 boracic 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. f 



From the whole of the above we may fairly infer that chlorophyl 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.J 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. 



t See the remarks on the green monkey. 



J Bakewell says that in some parts of Gloucestershire the wool acquires an orange color, in Hertfordshire and Warwick- 

 shire it is 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 rinying 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., v. 1, Monkeys, p. 141.) We also read of the blue goat of the Capo 

 of Good Hope. (See Gold. Hist, of Man, &c., 200.) 



