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FunctionIn 1827, Charles Wheatstone described a device he called the kaleidophone. It was designed to illustrate the persistence of vision of the human eye. It also was a simple means of generating Lissajous figures, and became widely used for that.
Related WorksRobert J. Whitaker, "The Wheatstone kaleidophone," American Journal of Physics, 61, no. 8 (1993): 722-728.