EXTERNAL PARTS OF THE FOOT 223 



EXTERNAL PARTS OF THE FOOT. 



THE CRUST OR WALL OF THE HOOF. 



The formation of the foot of the horse fits him, 

 as well as the ass, above all other animals, for the 

 service of man. In short, had the hoof of the 

 horse been cleft, he would have been incapacitated 

 for many of the useful departments of his employ- 

 ment ; and a correct knowledge of the structure of 

 every part of the foot is indispensably necessary to 

 render us scientific overseers of the farrier's art. 



The crust is that portion which reaches from 

 the termination of the hair to the ground. Its depth 

 is greatest in front, and is denominated the toe ; 

 it is more shallow at the sides, which are called 

 the quarters, and still less behind, which is termed 

 the heel. When the sole is placed on the ground, 

 the front exhibits an angle of about forty-five 

 degrees, differing, however, considerably in many 

 horses to the extent of the angle. But a healthy 

 and well-formed hoof very nearly approaches what 

 we have stated, that is, a fourth part of a semicircle. 

 With a greater degree of obliquity, it is said the 

 crust has " fallen in," and when the sole is too flat, 

 and is said to be pumiced, or convex ; and if the 

 front be more upright than the above angle, it is 

 the proof of a contracted foot with the sole too 

 concave. When the crust is deep at the heel, it is 

 a foot liable to contraction, thrush, sand-crack, and 

 inflammation. The pastern will be found too up- 

 right, and the horse will have a bad and unpleasant 

 action. If, on the other hand, the crust diminishes 

 too rapidly from front to back, and the heels are 

 low, this is always accompanied by too great ob- 



