Devices for producing sounds, consisting essentially of a disk pierced with holes arranged in a circle, rotated over a stream of compressed air, steam, or fluid, so that the stream is alternately interrupted and allowed to pass; their uses include giving signals or warnings and producing musical tones.
Devices for producing sounds, consisting essentially of a disk pierced with holes arranged in a circle, rotated over a stream of compressed air, steam, or fluid, so that the stream is alternately interrupted and allowed to pass; their uses include giving signals or warnings and producing musical tones.