Page:Horse shoes and horse shoeing.djvu/681

 crust, gradually removing a larger amount as the toe is reached, and inclining the instrument in a sloping manner on the outer edge, so as to cut off the external fibres shorter than the internal ones. At the toe, the crust should be cut down to the level of the sole. Here the knife may be used, and the remainder of this part removed until the white or yellow line marking the junction of sole and wall is reached. This is only to take place around the toe, and no more of the sole must be taken away than is absolutely necessary to give a level bed to the shoe; or, as Osmer says, 'in order to obtain a smooth and even surface, so far as the breadth of the shoe reaches, and no farther.' In the majority of cases I never allow the knife to be used for this purpose; causing all the work to be done by the rasp. The object in cutting off the external fibres at an angle from the quarters to the toe, is to give the edge of the hoof a rounded appearance, while it equalizes its thickness, and prevents it from splitting and breaking. The sole, frog, and bars must on no account, or under any conditions—unless those of a pathological nature—be interfered with in any way by knife or rasp. I have already shown the urgent necessity there exists for preserving these important parts of the plantar surface in their full natural strength. As certainly as they are interfered with, and their substance reduced, so surely will the hoof be injured. Nature has made every provision for their defence. They will support the contact of hard, soft, rugged, or even sharp bodies, if allowed to escape the terrible drawing-knife; while hot, cold, wet, or dry weather has little or no influence on the interior of the foot, or on the tender horn, if man does not step in to