8 THE HORSE'S FOOT, 



effect of the nails and shoe. The thickness of the horn 

 gradually diminishes towards the quarters and heels, particu- 

 larly on the inner side of the foot, whereby the power of yield- 

 ing and expanding to the weight of the horse is proportionably 

 increased, clearly indicating that those parts cannot be nailed 

 to an unyielding bar of iron, without a most mischievous 

 interference with the natural functions of the foot. In the 

 hind foot, the greatest thickness of horn will be found at the 

 quarters and heels, and not, as in the fore foot, at the toe. 

 This difference in the thickness of horn is beautifully adapted 

 to the inequality of the weight which each has to sustain, {he 

 force with which it is applied, and the portions of the hoof 

 upon which it falls. The toe of the fore foot encounters the 

 combined force and weight of the fore hand and body, and 

 consequently in a state of nature is exposed to considerable 

 wear and tear, and calls for greater strength and substance 

 of horn than is needed by any portion of the hind foot, where 

 the duty of supporting the hinder parts alone is distributed 

 over the quarters and heels of both sides of the foot. 



The bars are continuations of the wall, reflected at the 

 heels towards the centre of the foot, where they meet in a 

 point, leaving a triangular space between them for the frog. 



The whole inner surface of the horny crust, from the cen- 

 tre of the toe to the point where the bars meet, is everywhere 

 lined with innumerable narrow, thin, and projecting horny 

 plates,* which extend in a slanting direction from the uppei 

 edge of the wall to the line of junction between it and the 

 sole, and possess great elasticity. These projecting plates 

 are the means of greatly extending the surface of attach- 

 ment of the hoof to the coffin bone, which is likewise covered 

 by a similar arrangement of projecting plates, but of a highly 

 vascular and sensitive character ; and these, dovetailing with 

 the horny projections above named, constitute a union com- 

 bining strength and elasticity in a wonderful degree. 



The horny sole covers the whole inferior surface of the 

 foot, excepting the frog. In a well-formed foot it presents 

 an arched appearance and possesses considerable elasticity, 

 by virtue of which it ascends and descends, as the weight 

 above is either suddenly removed from it, or forcibly applied 

 to it. This descending property of the sole calls for our 

 especial consideration in directing the form of the shoe ; for, 

 if the shoe be so formed that the horny sole rests upon it, it 



• Page 48, fig. 2. 



