THE IIAIK. — COLOUR. M5 



PORES OP THE SKIN. 



Besides the openings already mentioned throngli whicli proceeds the 

 unctTious fluid that supples and softens the skin, there arc others more 

 numerous, by means of which a vast quantity of aqueous fluid escapes, and 

 perspiration is carried on. As in the human being, this actually exists in 

 a state of health and quietness, although imperceptible; but when the 

 animal is excited by exercise, or laboui-s under some stages of disease, it 

 becomes visible, and appears in the form of di'ops. 



This process of perspiration is not, however, so far under the control of 

 medicine as in the human being. 



We are not aAvare of any drugs that will certainly produce it. Warm 

 clothing seems occasionally to effect it, but this is more in appearance than 

 reality. The insensible perspiration cannot escape through the mass of 

 clothing, and assumes a visible form. This, perhaps, is the case when 

 sheep-skins are applied over the back and loins in ' locked jaw.' They 

 produce a good efl'ect, acting as a warm poultice over the part, and so 

 contributing to relax the muscular spasms. There are, however, a few 

 medicines, as antimony and sulphur, that have an evident and very con- 

 siderable effect on the skin. 



Of the existence of absorbent vessels on the skin, or those which take 

 up some fluid or substance, and convey it into the circulation, we have 

 satisfactory proof. A horse is even more easily salivated than the hiiman 

 being. Salivation has been produced by rubbing a splint with mercui'ial 

 ointment, previous to blistering ; and a very few drachms rubbed on the 

 inside of the thighs will probably produce a greater efiect than tho 

 practitioner desii'es. 



THE HAIE. 



The hair is the natural clothing of all our domestic quadrupeds. It is 

 some protection from violence, and more so from cold ; and it varies with 

 the climate in which they live. It springs from below the skin. There 

 are found on the cellular and fatty substance immediately in contact with 

 the internal surface of the skin, numerous little bulbs, which penetrate into 

 and pass through the skin, and which arriving at the cuticle the hair 

 protrudes from the summit of them. The haii' itself, when examined 

 through a microscope, is seen' to be a little tube containing a pulpy matter, 

 which runs through the whole length of it, and by which, probably, the 

 hair is fed and rendered pliant, and the loss of which under disease may 

 add to the hard and unthrifty feeling of the coat of a horse out of condition. 

 There is no essential difference in the structure of the hair, in different parts, 

 as the mane, the tail, and the body, except that the former is larger, longer, 

 and stronger. 



The base of the bulb whence the hair proceeds being beneath the true 

 skin, it is easy to perceive that the hair will grow again, although tho 

 cuticle may have been destroyed. A good blister, although it may remove 

 the cuticle, and seemingly for a while the hair ^vith it, leaves no lasting 

 trace. Even firing, lightly and skilfully performed, and not penetrating 

 through the skin, leaves not much blemish ; but when, in broken knees, 

 the true skin is cut through or destroyed, there will always remain a spot 

 devoid of hair. 



COLOUR. 



The colour of the hair admits ef every variety, and each colour becomes 

 in turn fashionable. Like that of the skin, it is influenced by, or depends 

 on, the mucous mesh-work under the cuticle. There are comparatively 



