and the mouth and neck relaxed, the spine also would be freed, and the buck-jump could not be executed.
Some horses, already trained, when they have their girths too tight will buck-jump. But, in general, the movement is consequent to some provocation, and employed by the horse as a defense. Not infrequently, a horse, having once freed its back from its rider's weight, will continue to practice this defense until it develops the habit.
Whether the buck-jump be sporadic or the result of a fixed habit, the reason is always the same — the horse refuses to go forward. It makes no difference what the reason is, whether the girths are too tight or whether the weight of the rider is greater than that to which the horse is accustomed, the result is the same.
The remedy is to see that the girths are not too tight, and to accustom the horse to the rider's weight. But when the horse begins the defense, the rider should at once lift its head as high as possible. In this position the horse can raise its front legs, but not its hind ones, which remain on the ground. If, then, the rider is sufficiently sure of himself, he should make the horse back. This will prevent the rigidity of the coupling, and the hind legs will act in alternation. The result will be the walk or the trot, but not the buck-jump.
The effect of too tight a girth is to inhibit the action of the great pectoral muscles, so that these do
