| The Kaleidophone is a simple physical system that its
inventor, Charles Wheatstone (1802-1875) called a "Philosophical Toy."
It produces optical figures in space that may be enjoyed in their own right,
or may be the source of considerable analysis.
There are several different versions of the Kaleidophone, but in all cases a slender rod, fixed at one end, is set into transverse vibrations. A small, polished bead fixed to the end of the rod reflects light from a light source, enabling the motion to be followed. In this example at St. Patrick's College in Maynooth, Ireland and sold by Yeates of Dublin, the vibrating system consists of two slender metal blades, fixed end-to-end with their flat dimensions at right angles. Another version of the Kaleidophone was made by Rudolph Koenig.
Wheatstone published an account of the device in 1827. Its name derives from Kaleidoscope, the optical device which had recently been devised by the Scottish physicist David Brewster.
REFERENCE: Thomas B. Greenslade, Jr., "Nineteenth Century Textbook Illustrations LI: The Kaleidophone", Phys. Teach., 30, 38-39 (1992)