The curb, if used, requires always a light hand to manage it; and the horse should never be put to do any thing in a curb at which he is not perfectly ready. The curb is adapted for acting in a direct line only: the snaffle should be used in all other cases. Still, as to all these qualities, the transitions must be gradual. Were the rider, passing over that degree of restraint which is derived from the easy or gentle hand, to go at once from a firm to a slack one, he would deprive his horse of the support he trusted to, and precipitate him on his shoulders. On the contrary, were he to pass from the slack to the tight rein all at once, he would give a violent shock to the horse’s mouth. All the operations of the hand, then, should be firm, gentle, and light; and in these, the fingers and wrist alone must act. Certain liberties called descents of the hand, are also taken with well-bred horses. These are made three different ways:--by advancing the arm a little, but not the shoulder, still keeping the usual length of rein, or by dropping the knuckles directly and at once upon the horse’s neck;--by taking the reins in the right hand, about four fingers’ breadth above the left, and letting them slide through the left, dropping the right hand at the same time upon the horse’s neck;--and by taking the end of the reins in the right hand, quitting them entirely with the left, and letting the end of them fall upon the horse’s neck. These graceful freedoms must never be used but with great caution, when the horse is quite together, and in hand; and the rider, by throwing back his body, must counterbalance the weight of the horse upon his haunches. There are still minuter rules belonging to this head; for instance, both snaffle reins being in one hand, and that in the first position,--if we open the first and second fingers, we slacken the right rein;--if we open the little finger, we slacken the left rein;--if we shut the hand entirely, and immediately open it again, we lessen the tension of both reins. By these methods, we may relieve and freshen the two bars in which the feeling and appuy resides. So also in the second descent of the hand. While the right hand holds the reins, we may slide the left hand up and down these in that degree of appuy which belongs to the easy and slack hand: during which the horse will endeavour to preserve that mutual sensation between the mouth and the hand, which makes him submit with pleasure to constraint. By this play of the rein and movement of the bit to avoid pressure in one continued way, the horse’s head is kept high, and his neck and crest are raised. THE GUIDANCE OR AIDS.