166 DISEASES OP THE HOESE. 



e Of the infinity of pores the skin exhibits upon its 

 surface, probably the greater number transmit hairs, 

 but there are crowds of others, which are denominated 

 the perspiratory pores, from their being known to emit 

 an imperceptible vapour, distinguished as the insen- 

 sible perspiration ; that which is sensible being the 

 ordinary sweat. 



e . . . Again, there is another set of pores of larger 

 size, more discernible in some places than in others, 

 which are the mouths of follicles (or glands), from 

 which issues a waxy matter, and those parts of the 

 skin subject to friction are in particular beset with 

 them ; in fact, the unctuous matter furnished by them 

 preserves the skin soft and supple, and in some places 

 keeps up a constant greasiness of the surface. 



f The skin at the bend of the knee and hock has a se- 

 cretion of this nature, which, from irritation now and 

 then becomes augmented, and, from want of cleanliness, 

 grows inspissated, and collects about the parts, and, if 

 the incrustation be not disturbed, will generate a foul 

 ulcerous sore. Lameness, of course, must result from 

 this as soon as pain or stiffness is felt in flexing the 

 limb. 



( The skin of the heel of the horse possesses very many 

 of these glandular pores, through which oozes an unctu- 

 ous secretion having a peculiar smell, and this it is that 

 gives the well-known softness, suppleness, and greasy 

 feel to the part. An unusual flow of this matter, some- 

 what altered in its nature, is what gives rise to grease. 



f The cuticle (or outer skin) is a thin, tough, inor- 



