Mary Hallock Greenewalt began as a concert pianist but, stimulated by theatrical
lighting, she became interested in color music about 1906 and gave her first
concert, in Philadelphia, in 1911. She toured extensively the following year
and seems to have performed regularly until the late 1930's on a series of
increasingly sophisticated instruments. . . She often composed
colour-accompaniments to pieces with strong programmatic associations, such as the
first movement of Beethoven's 'Moonlight' Sonata. . .
--John Gage, Color and Culture