THE HOOF. 



299 



The horn of the wall, sole, and frog should be thick, 

 hard and tough, so as to resist in an efficient manner the 

 effects of wear. Moisture has a well-marked softening and 

 weakening influence on the horn, and it consequently 

 affects the form of the foot. We tind that the drier 

 the climate, the stronger is the horn of horses reared 

 in it ; the more upright are the hoofs ; and the more 



Fig. 377. — Kcir view of unshod olT hind hoof (?,rds nat. size). 



concave are the soles. When the horn of the wall and 

 sole is weak, it cannot efficiently support the weight 

 thrown on the leg, and the foot will have a tendency to 

 become flat. The feet of horses bred in Austraha, for 

 instance, are stronger than those produced in England, 

 owing to the climate being drier. We know from ex- 

 perience, that moisture has probably a great influence 

 in quickening the growth of horn, as we may see in horses 



