the prominent parts at the extremities of a horse-hoe, bent downwards, and forged to a sort of point.
Calkins are apt to make horses trip; they also occasion bleymen, and ruin the back sinews. If fashioned in form of a hare's ear, and the horn of a horse's heel be pared a little low, they do little damage; whereas, the great square calkins quite spoil the foot.
Calkins are either single or double, that is, at one end of the shoe, or at both; these last are deemed less hurtful, as the horses can tread more even.