(_Unter den Linden._)
Make a box half as wide and high as long. At one end place a mirror,
exactly the size of the board, and fixed firmly against it, and remove
the quicksilver within a circle agreeing with an eyehole cut in the end.
Back the opposite end in the same way with a plane mirror.
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_.)