kaleidophone
{{Short description|Physics tool}}
{{For|the Bloom de Wilde album|Bloem de Ligny}}
File:Kaleidophone-IMG 7007-gradient.jpg in Paris.]]The kaleidophone is a "philosophical toy" that produces moving optical figures.
History
The kaleidophone was invented by Charles Wheatstone, who published an account of the device in 1827.https://people.seas.harvard.edu/~jones/cscie129/papers/koenig_apparatus/Kaleidophone/Kaleidophone.html {{Dead link|date=February 2022}}
The name "kaleidophone" was derived from the kaleidoscope, an optical toy invented in 1817 by David Brewster.{{Citation needed|date=April 2024}}
Wheatstone's photometer was probably suggested by this appliance. The photometer enables two lights to be compared by the relative brightness of their reflections in a silvered bead, which describes a narrow ellipse, so as to draw the spots into parallel lines.{{Citation needed|date=April 2024}}
There are several different versions of the kaleidophone, but in all cases at least one slender rod is fixed at one end and has a shiny bead fixed to the other end of the rod. As the rod vibrates the spot is seen to describe Lissajous curves in the air, like a spark whirled about in the darkness.{{Cite web |title=Kaleidophone |url=http://physics.kenyon.edu/EarlyApparatus/Acoustics/Kaleidophone/Kaleidophone.html |access-date=2017-05-23 |archive-date=2022-03-15 |archive-url=https://web.archive.org/web/20220315223534/http://physics.kenyon.edu/EarlyApparatus/Acoustics/Kaleidophone/Kaleidophone.html |url-status=dead }}
References
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