The kaleidophone is a " philosophical toy" that produces moving optical figures. 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 curve A Lissajous curve , also known as Lissajous figure or Bowditch curve , is the graph of a system of parametric equations : x=A\sin(at+\delta),\quad y=B\sin(bt), which describe the superposition of two perpendicular oscillations in x and y dire ...

s in the air, like a spark whirled about in the darkness. The kaleidophone was invented by

Charles Wheatstone Sir Charles Wheatstone FRS FRSE DCL LLD (6 February 1802 – 19 October 1875), was an English scientist and inventor of many scientific breakthroughs of the Victorian era, including the English concertina, the stereoscope (a device for di ...

, who published an account of the device in 1827.https://people.seas.harvard.edu/~jones/cscie129/papers/koenig_apparatus/Kaleidophone/Kaleidophone.html The name "kaleidophone" was derived from the

kaleidoscope A kaleidoscope () is an optical instrument with two or more reflecting surfaces (or mirrors) tilted to each other at an angle, so that one or more (parts of) objects on one end of these mirrors are shown as a regular symmetrical pattern when v ...

, an optical toy invented in 1817 by David Brewster. Wheatstone's

photometer A photometer is an instrument that measures the strength of electromagnetic radiation in the range from ultraviolet to infrared and including the visible spectrum. Most photometers convert light into an electric current using a photoresistor, ...

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.

References

External links

*{{Commons category-inline Optical toys English inventions 1820s toys Patterns 19th-century inventions Traditional toys