' SHOEING AFTER CORN^ 323 



surface covering that of the wall but not extending to any 

 portion whatever of the sole. In horses with narrow upright 

 hoofs and in those working on soft ground this shoe is quite 

 satisfactory, but is liable, under opposite conditions, to produce 

 separation of the wall. By increasing the width of the surfaces 

 of contact between shoe and hoof, or by applying a bar shoe, 

 this is, however, entirely avoided. 



In horses with weak heels the ordinary shoe is apt to cause 

 the heel to turn inwards and its use to be followed by pro- 

 duction of corns and contraction of the hoof. The cause is the 

 shape of the shoe, which relieves the frog and sole of weight 

 at the expense of the heels, which yield, bend inwards, and 

 cause lameness. The lameness disappears, when, by the appli- 

 cation of a bar shoe, the frog is forced to sustain a portion of 

 the weight. In sandcrack and cracks of the bar, this form of 

 shoe supports the posterior part of the foot, and by increasing 

 its functional activity encourages growth and expansion. Where 

 a hoof shows more than one crack the action of the bar shoe 

 is assisted by applying a thick leather and padding the space 

 between it and the sole of the foot with tow. A portion of the 

 weight is then borne by the frog and by the sole itself. A 

 bar shoe can always be applied, even when one quarter or 

 quarter and heel are much broken, provided the frog be sound 

 and fairly developed. Should the frog be healthy, but small, 

 it may be built up by applying gutta-percha or the special 

 cement later described. 



In case of the frog being affected with thrush, the pro- 

 cedure is as follows : — After the shoe is fitted, all loose pieces 

 of horn are removed by a searcher, the parts thoroughly washed 

 with water, then with 5 per cent, solution of carbolic acid, 

 creosote, or creolin, the entire ground surface of the hoof 

 smeared with wood tar or Venice turpentine, a pad of tow 

 applied, a leather sole fitted over all and the shoe nailed on. 

 The bar shoe should not be employed in navicular disease, 

 double side-bones, or in the case of picked-up nails (which 

 almost always enter the frog). 



The bar shoe permits any part of the bearing surface of the 

 hoof to be left uncovered and to be reheved of pressure without 

 stoppage of work. The entire frog is capable of bearing weight, 

 but the posterior part is best suited for the purpose, and there 

 the bar should take its bearing. 



