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MOTION AND EQUIPOISE.
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other parts to bring it to the place where it means to go. As the man A, who moves the arm with a club E, and brings it to the opposite side B, assisted by the motion of the whole body.

Chap. XCIII.The Action of Jumping.

Nature will of itself, and without any reasoning in the mind of a man going to jump, prompt him to raise his arms and shoulders by a sudden motion, together with a great part of his body, and to lift them up high, till the power of the effort subsides. This impetuous motion is accompanied by an instantaneous extension of the body which had bent itself, like a spring or bow, along the back, the joints of the thighs, knees, and feet, and is let off obliquely, that is, upwards and forwards; so that the disposition of the body tending forwards and upwards, makes it describe a great arch when it springs up, which increases the leap.

Chap. XCIV.Of the three Motions in jumping upwards.

When a man jumps upwards, the motion of the head is three times quicker than that of the heel, before the extremity of the foot quits the ground, and twice as quick as that of the hips; because three angles are opened and extended at the same time: the superior one is that formed by the body at its joint with the thigh before, the second is at the joint of

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