360 DEFOKMITIES AND DISEASES OF THE HOOF. 



B. Mechanical Methods. 



7. De la Broue's slipper shoe tends to expand the entire wall 

 of the hoof. It is claimed that the bearing margin lying on 

 an oblique surface spreads outwards under the pressure of the 

 horse's body-weight, and that the shoe is useful in all cases of 

 contraction where the coronary margin is wider than the bear- 

 ing margin of the hoof. It exposes tlie white line, however, 

 to excessive strain, and is, therefore, no longer used in this 

 form, especially as there are other and less dangerous methods 

 of expanding the hoof. By confining the outward slope of the 

 bearing surface to the heel (or heels, when both sides of the 

 foot are affected), it, however, renders good service. Never- 

 theless great care is needed in determining the exact amount 

 of slope, and the distance to which it should extend, otherwise 

 severe lameness results. It is usually sufficient if the outer 

 margin of the hoof surface is ^ to -i- inch lower than the 

 inner, and this oblique surface should only extend as far 

 forwards as the wall of the heel forms with the ground an 

 acute angle. The same principle may, of course, be applied 

 to the heels of bar shoes. 



8, SJiocs vAth bar-dijjs. — (a) De Fay's is a fiat shoe with a 

 clip at the inner margin of either heel. The clips should lie 

 in the lateral furrows of the frog, exactly at the points where 

 the wall is refiected to form the bars. They should fit evenly 

 on the bars, but should not extend to the bottom of the lateral 

 furrow of the frog. The foot surface at the heel must be 

 absolutely horizontal. The shoe should be cooled and nailed 

 on, and the dilator (fig. 334) then adjusted with its cheeks 

 between the heels, which are expanded by turning the screw 

 h. This forcibly widens the hoof. The method requires the 

 greatest care, and is certainly not often applicable. On the 

 first occasion it is sufficient to dilate the parts y\j to -|- inch, 

 and nothing further should be done until the space gained 

 can be filled with horn, that is, in from ten to fourteen 

 days. 



(h) Hartniann's expanding shoe (fig. 335) is narrow, and 

 possesses one or more saw-cuts on its inner border. When it 

 is desired to dilate the hoof equally, these cuts are made at 



