Prepare grooves at right angles across the box, in which will slide two sheets of cardboard, painted on both sides with trees and overarching foliage, with the lights cut clear out, taking care that a bough will prevent the eyehole being reflected in the opposite glass.
Paint two other boards similarly with foliage, and cut the lights out and set them against the mirrors.
Cover the box with gauze, and frame a sheet of ground glass to form the lid, which should be firmly fastened on. The bottom is to be painted sandy colour or green, or may be varnished and strewn with moss whilst wet. When viewed with a strong light, the effect will be as of an endless vista, gradually fading away in the distance.
(See “The Endless Vista,” p. 300, Magician’s Own Book.)
THE PERSPECTIVE GLASS.
At one end of a box, twenty inches long and twelve high and wide, place a concave mirror, of which the focus should be about fifteen inches from the reflecting surface. Blacken the other end inside, and cut an eyehole in it.
Darken the mirror by covering the top in from it to a little less than half way along the box, where a blackened frame should be set, with a sufficient opening to let the mirror reflect any object just under the eyehole at the other end, where a grooved cleat permits picture-slides to be inserted. Cover the other part of the box with ground glass or other transparent media, to keep the inside from being seen.
Fig. 126.
If you must use artificial light, let an aperture be practised in the mirror end, so that the source of the illumination cannot be perceived.