If, moreover, the hand be held steady, as the horse advances in the trot, the fingers will feel, by the contraction of the reins, a slight tug, occasioned by the cadence of every step; and this tug, by means of the correspondence, is reciprocally felt in the horse’s mouth. This is called the APPUY. While this relation is preserved between the hand and mouth, the horse is in perfect obedience to the rider, and the hand directs him, in any position or action, with such ease, that the horse seems to work by the will of the rider rather than by the power of his hand. This is called the SUPPORT. Now, the correspondence or effective communication between the hand and mouth,--the appuy, or strength of the operation in the mouth,--the support, or aid, the hand gives in the position or action,--are always maintained in the manège and all united paces. Without these, a horse is under no immediate control, as in the extended gallop, or at full speed, where it may require a hundred yards to pull before we can stop him. THE ACTION. The degree of correspondence, appuy, and support, depends, in horses otherwise similar, on the relative situation of the hand. The act of raising the rider’s hand increases his power; and this, raising the horse’s head, diminishes his power. The depressing of the rider’s hand, on the contrary, diminishes his power; and this, depressing the horse’s head, increases his power. On these depend the unitedness or disunitedness in the action of the horse. A writer on this subject (Beranger, we believe) gives the following useful illustration:--“If a garter were placed across the pupil’s forehead, and a person behind him held the two ends in a horizontal direction, the pupil, if he stood quite upright, could not pull at the person’s hand, nor endure the person’s hand to pull at him, without falling or running backwards.” This is the situation of a horse when united. Accordingly, when the pupil felt the hand severe, or expected it to pull, he would guard against it by bending the body, projecting the head, and planting one foot behind. This is the situation of a horse when disunited, or defending himself against the heaviness of the hand. Hence the perpetual pull of a timid rider, or a heavy insensible hand, cannot keep a horse united, because the horse cannot then bear its severity. Thus heavy hands make hard-mouthed horses; and hence it is in this condition that we generally find horses, for the best broke become so, if ridden a few times by an ignorant horseman. In such cases, the horse makes the rider support the weight both of his head and neck, or goes on his shoulders, and is apt to stumble.