COVERING OF THE HOUSE. 133 



dressing skins, the cellular layer just now de- 

 scribed, the layer which remains to be de- 

 scribed, and the paint, are all scraped off, and 

 nothino- remains but the true or real skin the 



O 



layer now under consideration. 



I do not mean to say here that leather con- 

 sists of nothing but this skin, for I know that 

 tannin, as the chemists call it, combines with 

 the raw hide, to make most kinds of leather; 

 but I mean that no animal substance goes to 

 form the leather, except this single membrane. 



This membrane, or real skin, is principally 

 composed of an almost endless number of small 

 blood vessels, running along and crossing each 

 other in nearly every direction, together with 

 nerves quite as numerous, intermingled with 

 them. The nerves, however, seem to be en- 

 larged on the surface of this membrane, and 

 to form little rows of eminences or pimples. 

 These are seen plainest on the tongue, and on 

 the balls of the fingers ; but exist, of a small 

 size, all over us. You cannot prick the skin 

 with the finest needle in the world, without 

 hitting at least one nerve and one blood vessel. 

 For there would be pain in doing so : and this 

 12 



