Stereoscopic, or 3-D photography, works because it is able to create the illusion of depth as in 3-D films. Human eyes are
set about two-and-a-half inches apart, so each eye sees a slightly different image. If one takes two slightly different photographs
that same distance apart, it is possible to converge them into a single image and recreate that illusion of depth.
Though most associate Sir David Brewster with the invention of the stereoscope, it was physicist Sir Charles Wheatstone who,
in 1838, gave an address to the Royal Scottish Society of Arts on the phenomena of binocular vision and proposed that the
equipment be called a “stereoscope to indicate its property of representing solid figures.” Eleven years later Brewster described
a binocular camera, and the first stereoscopic photographs began to be produced. By the end of the century, every Victorian
parlor had a stereoscope. Protean views, providing the illusion of movement from day to night, are considered pre-cinema
devices, a pre-cursor to the motion picture.