SANDCRACK. 



175 



supplies will consequently be wanting in strength. In some cases 

 —generally those of hereditary predisposition— the horn is natu- 

 rally so weak that it would appear liable to split on its being 

 subjected to any violent strain. The horn of the feet of almost all 

 horses which are reared on wet, marshy land is more porous and 



Fig- 51.— Bar shoe, designed to give pressure on the frog. 



ready to split than is that of those brought up on dry soil. The 

 pernicious system of using seated shoes and of paring the frog, 

 induces sandcrack by the unnatural mamier in which the entire 

 weight of the animal is thrown on the crust of the foot, instead of 

 being distributed, as nature intended it to be, between the wall, 

 the frog, the outer portion of the sole, and the bars; irritation 



