COKNS. 221 



exactly covering those of the foot, will be found to be a little 

 within their outer margin and somewhat in front of their rearmost 

 point. As the horn of the ground surface of the foot is hardest 

 on the outside and at the extreme end of the heels, the heel of the 

 shoe in the case just described, will, as a rule, be more or less 

 embedded in the comparatively soft horn invaded by it, with the 

 probability of a corn being formed. As regards keeping the heels 

 of the shoes of the fore feet short, those who ride or own 'cross- 

 country horses, are impaled on the horns of a dilemma : one 

 being the risk of a com ; the other, tliat of the shoe being pulled 

 ofi by rhe hind foot, especially, when jumping and even galloping 

 on heavy ground. As' the latter danger admits of no escape, we 



Seat of corn 

 Bar 



Fig. 73. — Ground surface of horse's foot. 



must face ,the corns, which can be prevented by frequent shoeing, 

 say, at least once a month. As a horse does not brush with tlie 

 heel of a foot, but with its quarter, when he is shod, the outer 

 edge of the inner heel of the shoe of a fore foot should be 

 fitted so as to slightly project outside the wall. When shoes are 

 kept on an inordinately long time, the web of the shoe, generally 

 at the toe, may become so thin, as to cause the shoe to get out 

 of shape and press on the spot which is most liable to com. 



The use of calkins may cause corns by localising, on the heels, 

 the effects of concussion with the ground. In some rare cases, 

 corns are produced by the horse treading on a stone or other 

 hard body, a result that will very seldom occur if the sole be not 

 " thinned." When the ground surface of the foot has been reduced 

 too much, the sole may become bruised at any part pressed upon 

 by the web of the shoe, especially if the animal is worked at a 

 fast pace and on hard ground. As previously mentioned, some 

 horses have such weak feet that it is almost imfM>ssible to prevent 



