Provided the frog comes largely in contact with the ground, there is not usually much danger of slipping; but as it is not always possible to secure this, recourse is had to artificial means. Among these are calkins, which, as has been already mentioned, are objectionable in all but slow-paced horses; and indiarubber pads of various forms to fit between the shoe and the hoof, and come in contact with the ground, aiding, as well, in diminishing concussion.
For ice-covered roads there are numerous contrivances. In ordinary "roughing," the shoes are taken off and a sharp calkin is turned up; but this requires a forge, much time, is injurious to the horse's feet, does not last long, and is expensive. "Frost-nails" are sometimes employed, but these also require a farrier, last a very short time, and likewise damage the hoofs. Screw studs or pegs are more convenient, screw holes being made in the shoes when they are first put on, into which sharp or blunt pegs are screwed as occasion may require. But these sometimes break at the neck, or fall out, require to be screwed in, and the thread is liable to become rusty, while they are somewhat expensive. Another much simpler and cheaper method is the introduction of a sharp square peg' into a square hole punched in each branch of the shoe, and, if necessary, at the toe - this stud and the hole having a slight taper, which permits the former to be inserted and removed: it should not project beyond the foot surface of the shoe. Or, the studs and holes may be round and tapering in the same manner. Blunt studs may be used when there is not ice, or on wooden pavements, or asphalte. When required to be used, these studs are merely inserted into the holes and require a smart blow; when it is desired to remove them, a few taps on each side, and a blow on the face of the shoe, will generally make them jump out
This stud method of winter shoeing has been adopted for some years in Her Majesty's household cavalry, and is in use in most of the continental armies.