PAEIlfa AND EASPINa. 91 



The injuries wHcli result from the excessive use of the rasp 

 are of a different and somewhat less dangerous character than 

 those inflicted with the drawing knife. The hoof contains 

 within its homy substance a certain amount of latent moisture. 

 It is this latent moisture which keeps the organ strong and 

 toagh; and any agency productive of inordinate evaporation 

 from its surface (a small amount is constantly exhaling), tends 

 naturally to render it dry, imyielding, and brittle. To prevent 

 this, nature has so constituted the foot, that it secretes a 

 peculiar substance which is spread in abundance over the 

 external surface of the crust. This substance consists prin- 

 cipally of silex or flint ; it is in fact a coating of flint, which 

 dries and hardens, thus preventing undue evaporation as well 

 as protecting the hoof from the heat of the sun,* Man, 

 however, so clever and so wise withal, must improve upon 

 Nature and beautify her works, and his notion of doing this 

 upon the foot of the horse, is by paring and rasping the organ, 

 which for the time beiag perverts her ends and intentions. The 

 rasping which a hoof ought to undergo is slight in comparison 

 with that which usually takes place. It should be rasped 

 immediately below where the naUs issue from the horn, and at 

 the border of the foot resting upon the shoe. Easping imme- 

 diately below where the nails are clenched, allows of their being 

 more securely fixed. It is also necessary to the border conti- 

 guous to the shoe, and to the toe to shorten it. In cases also 

 where the horn grows more rapidly at the toe than at the heels 

 and quarters, shortening the former by rasping will materially 

 aid in deepening the latter. 



* We observe a similar arrangement on the stem of the sugar cane. 

 By bending a piece of cane, the experimenter may notice upon the bent sur- 

 face, a nimiber of loosened particles of metallic looking matter. This is the 

 siliceous covering of the cane. Similar deposits may be observed upon the 

 outer siuiace of straw, and most of the dried grasses. 



