The Endless Gallery.
A novel little optical illusion is the "endless gallery," the delight of English children in the first part of this century. Here are the directions:
Make a box 18 inches long, 12 wide, and 9 deep, and against each end place a plane mirror within 1/8 of an inch of the height of the box. Cut a small hole through one end, and likewise through the mirror resting against it. Mirrors should also be placed on the longer sides of the box. Cut grooves at various lengths across the box, and in these fit small colored figures, trees, statuary, etc., previously cut out from card-board, and bearing the same representation on either side. At each end place similar figures, leaving plenty of mirror space behind.
The top of the box should be of ground-glass or oiled paper. Looking through the eye-hole, a vista of enormous length and breadth is seen, seemingly endless.
Vincent V. M. Beede.