The patient is bound on the ladder, and while extension is made on the arm, the head of the humerus is pulled outwards by a thong passed inside it.

[Fig. 29] shows the reduction of the wrist, extension and counterextension are made by thongs affixed below and above the wrist by clove-hitches; while [Fig. 30] shows the reduction of the ankle on similar principles.

(In the case of the wrist the ladder is shown tilted up on its side, in order to bring the parts into view.)

A portable winch of more powerful principle was the Glossocomum of Nymphodorus. It is shown in [Fig. 31]; first, as it appeared when closed and ready for use, and next, with one of the shutters removed to show its internal construction.

It will be seen to consist of a crank, the rotation of which causes a worm on it to turn a cogged wheel.

Round the axle of the cog wheel are ropes passing to another axle, the circumference of which is increased by drums so as to multiply the power, after the manner shown in the figure. One whole turn of axle moves cogged wheel forward one cog. Some of the inner details of the winch are shown below. Another portable winch was the Trispastum of Apelles or of Archimedes. Its construction is shown in [Fig. 32], which shows the sides removed to display the working. In actual use, however, it was closed in like the last winch.

Reduction by Means of Inflating a Bladder. In describing the reduction of the dislocation of the spine Hippocrates says that he has tried to reduce the deformity by inflating a bladder affixed to a bronze tube and placed under the spine. The experiment, however, did not succeed for when the man was fairly extended the bladder yielded, and the air could not be forced into it, and besides, the hump of the patient was apt to slip off the bladder.

Hippocrates says he has written this expressly, for it is a valuable piece of knowledge to learn what things have been tried and have proved ineffectual, and wherefore they did not succeed.

Again he says that reduction by the bladder was celebrated in the case of the hip joint.

It is not a powerful method. It should be placed between the thighs uninflated so that it may be carried as far up in the perineum as possible, and the thighs, beginning at the patella, are to be bound round with a swathe, as far up as the middle of the thigh, and then a bronze pipe is to be introduced into one of the loose feet of the bladder and air forced into it. The patient is to lie on his side with the injured limb uppermost.