Forging is that defect of the horse’s gait by reason of which, at a trot, he strikes the ends of the branches or the under surface of the front shoe with the toe of the hind shoe or hoof of the same side. Forging in a pacer is termed “cross-firing” and consists in striking the inner quarter, or the under surface of the inner branch of a front shoe with the toe of the diagonal hind shoe or hoof. Forging is unpleasant to hear and dangerous to the horse. It is liable to wound the heels of the forefeet, damages the toes or the coronet of the hind hoofs, and often pulls off the front shoes. [Illustration: FIG. 148. Right front shoe with concave ground-surface (“convex iron”) to prevent “forging.”] [Illustration: FIG. 149. Right hind shoe with lateral toe-clips to prevent “clicking” and the various injuries due to forging.] _Causes._—1. Faulty conformation; for example, horses that stand considerably higher at the croup than at the withers; horses with long legs and short bodies; horses that “stand under” in front and behind. 2. Using horses on heavy ground, unskilful driving, allowing a long-necked, heavy-headed horse to carry his head too low; riding without holding a horse to his work by feeling his mouth and pressing the knees against his sides. 3. Fatigue frequently leads to forging, even in horses that are well built and properly shod. It may also occur in the act of vaulting over an obstacle. 4. Poor shoeing, especially too long toes upon the front and hind hoofs, and too long front shoes. The aim of the shoer should be to facilitate the quick and easy “breaking over” of the =front foot=, so that it may get away before it is overtaken by the hind foot. The toe of the front hoof should be fairly short and rolled; the quarters spared. The front shoe should be light, rolled at the toe and =no longer and no wider= than the hoof. The ends of the branches of a flat shoe, and also the heel-calks, in case they are needed to elevate a heel that is too low, should be bevelled from the hoof-surface of the shoe downward and forward under the foot. Such short heel-calks, bevelled to prevent forging, are called “forging calks.” If the horse continues to forge between the branches and against the ground-surface of the shoe, concaving this surface will prove advantageous (convex iron). The form of the front shoes of horses that forge should represent merely a prolongation of the hoof.