Wheat stone's bridge

See under bridge. W's mirror stereoscope. A s. which consists of two plane mirrors joined together at right angles, in which are reflected the projected images corresponding to the right and left eye, are placed at the limit of distinct vision in front of the mirrors at an angle of 45 ° to their reflecting surface. The two eyes then see the reflected images united at one point. [Charles Wheat stone, English physicist, 1802-1875.]