“Those who are to participate in the apparent gyrations of the swing—and there may be quite a number who enjoy it simultaneously—are ushered into a small room. From a bar crossing the room, near the ceiling, hangs a large swing, which is provided with seats for a number of people. After the people have taken their places, the attendant pushes the car and it starts into oscillation like any other swing. The room door is closed. Gradually those in it feel after three or four movements that their swing is going rather high, but this is not all. The apparent amplitude of the oscillations increases more and more, until presently the whole swing seems to whirl completely over, describing a full circle about the bar on which it hangs. To make the thing more utterly mysterious, the bar is bent crank fashion, the swing continues apparently to go round and round this way, imparting a most weird sensation to the occupants, until its movements begin gradually to cease and the complete rotation is succeeded by the usual back and forth swinging. The door of the room is opened, and the swinging party leave. Those who have tried it say the sensation is most peculiar. “The illusion is based on the movements of the room proper. During the entire exhibition the swing is practically stationary, while the room rotates about the suspending bar. At the beginning of operations the swing may be given a slight push; the operators outside the room then begin to swing the room itself, which is really a large box journaled on the swing bar, starting {xxi} it off to correspond with the movements of the swing. They swing it back and forth, increasing the arc through which it moves until it goes so far as to make a complete rotation. The operatives do this without special machinery, taking hold of the sides and corners of the box or ‘room.’ At this time the people in the swing imagine that the room is stationary while they are whirling through space. After keeping this up for some time, the movement is brought gradually to a stop, a sufficient number of back and forth swings being given at the _finale_ to carry out the illusion to the end. [1] MAGIC, STAGE ILLUSIONS, AND SCIENTIFIC DIVERSIONS, INCLUDING TRICK PHOTOGRAPHY. Compiled and edited by Albert A. Hopkins. With 400 illustrations. New York: Munn & Co. 1898. [Illustration: ILLUSION PRODUCED BY A RIDE IN THE SWING] {xxii} [Illustration: TRUE POSITION OF THE SWING]