Do you know what a Thaumatrope is?
A thaumatrope is a 19th century toy which uses the power of the eye to turn two images into one!A disc or card with two separate images on the front and back is twirled rapidly to create the illusion of one image.In the above example, an image of a horse on one side, and an image of a rider on the other side, are spun so fast on a string that the eye thinks they are one solid image.