Thaumatrope

Common card · No. 498738

A thaumatrope is an optical toy that was introduced in 1825. When the strings attached to the small illustrated disk are twirled quickly between the fingers, the depicted elements on either side of the disk appear to blend into one image. It was explained as the result of visual impressions lingering in the mind for about one-eighth of a second after the image has been removed. Examples of common thaumatrope pictures include a bare tree on one side of the disk, and its leaves on the other, or a bird on one side and a cage on the other. Many classic thaumatropes also included riddles or short poems, with one line on each side. In addition to superimposing images, its "persistence of vision" effect is a disputed explanation for the cause of illusory motion in stroboscopic animation and film. Thaumatropes can provide an illusion of motion with the two sides of the disc each depicting a different phase of the motion, but no examples are known to have been produced until long after the introduction...

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