Charles Wheatstone was a physicist whose fertile, questioning mind produced numerous discoveries and inventions in the fields of optics, acoustics, electricity, and telegraphy.

Wheatstone was born in Gloucester, England, to a family of musical instrument makers and dealers. He had no formal education in science. He was apprenticed to an uncle in 1816 as a musical instrument maker, and invented the concertina in 1829. His musical background led Wheatstone to experimental studies of acoustics, which in turn led to his appointment as professor of experimental physics at King's College, London, in 1834. Wheatstone held this position for the rest of his life, although he seldom lectured, concentrating instead on research in electricity and optics.

Wheatstone's contributions to acoustics included the kaleidophone, a device that produced a visual demonstration of sound vibration. He also made important discoveries about plate vibrations and vibrations in columns of air. In the field of optics, Wheatstone...