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 ion of the scapulo-humeralis articulation, high for the extension of the lower leg, these movements are made to occur alternately, both with the horse standing and in motion.

There are, then, three effects of the hand holding the reins. The first prevents movement forward. The second directs the body when in motion. The third raises and sustains the front hand either standing or moving.

The jambettes of the hind legs are obtained by the effects of the rider's legs, and involve nothing more than a flexion of a limb sustained for a short time. As soon as the effect has ceased, the horse's leg returns to the ground for the next stride. (Figure 29.)

The value of the jambettes of the hind legs is that they enable the rider to set the limbs at right angles to the ground and parallel to each other when the horse is standing; or when the horse is in motion, they enable the rider to secure an equal impulse from both hind legs.

For it is obvious that it is not by the lifted limb that the horse sends its body forward, but by the other which is on the ground. For example, the left hind foot cannot be lifted, unless the right hind foot is in contact with the ground, in order that the right leg may bear the load which the left has been supporting. The right leg is, therefore, in position for the impulsion. But when this impulsion is finished, the left leg will have returned to the