OR, A TREATISE ON PILE. 137 
standing the body is constantly imparting it to the earth.* This will, in part at least, 
explain why fur-bearing animals are provided with long hairs as well as short wool. Hach 
projecting hair is a lightning rod, (if one may so speak,) to extract electricity from the 
atmosphere ; at the same time that every movement of the animal, causes the hair and 
wool to rub together, and forming currents of electricity. There is not (as every one 
knows) a more effectual method of exciting electricity than by rubbing together hair and 
wool, as is done when the hand is passed briskly over the back of a cat; but all the fric- 
tion you can bestow upon the short hair of a dog will be attended with no such result. 
The hairs of the eye-brows shadow the eyes and preserve them from too great a glare of 
light; for the effectual performance of which function, the brows upon which they grow 
are provided with muscles, which are under the control of the will. The eye-brow hairs 
(supercilium) also protect the eye from the moisture which collects on the forehead, and 
which would otherwise run into the eyes. 
The hairs of the eye-lids (cilia) are bow-shaped, and crossing each other, form a screen, 
which prevents insects and fine particles of matter, which float in the atmosphere, from 
entering the eye. 
The hairs of the nasal passage and of the ears, also, prevent the ingress of insects. When 
in health the principal part of the air we breathe passes through the nose, the shape of 
which is well calculated for its conveyance to the lungs. ‘The sense of smell would 
appear to be placed in the nasal fosse, to give notice of the presence of any deleterious 
vapor, and the hair to prevent insects from obtruding. Hypogastric hairs subserve the 
same purpose, and in females particularly, to conduct off the moisture of the body. 
Sometimes the uses of hair are more temporary, and, in those cases, their endurance is 
of the same limited character. Of such, is the velvet coat, (as it is called,) which covers 
and protects the large vessels on the summit of the head of the Stag, previously to the 
sprouting of his antlers. 
Besides these, which are the direct and palpable uses of hair, there are others of an 
indirect and latent character, such as for secretion and insensible perspiration; with the 
functions of which we yet know too little to make them objects of particular discussion. 
Bostock is of opinion that the skin is the seat of an extensive system of exhaustion and 
absorption; although he acknowledges that it may be very difficult to determine the 
actual termination of the vessels, or the exact apparatus by which these functions are per- 
formed. (Syst. of Physig., p.50.) With these systems, (if they do exist,) pile is, doubtless, 
connected. 
We believe that the question has never been decided, whether the skin of our species 
has a chemical action upon the atmosphere ; in the case of the lower animals the affirma- 
tive seems to be admitted ; and, therefore, we think that we may be warranted in suggest- 
ing that another use of hair to them, may be to modify ¢hat action. We have very high 
authority for considering hairs as emunctories. Boerhave, Knophof, Haller, Blumenback 
* Magendie, (Précis Elem. 177.) very erroneously states that hair is a bad conductor of electricity, 
7 But see Biehat in Anat. Gen. 788, as to absorption of hair; also, Wilson on the Skin. 
