A barrel organ is a mechanical musical instrument consisting of bellows and one or more ranks of pipes housed in a case, usually of wood, and often highly decorated. The basic principle is the same as a traditional pipe organ, but rather than being played by an organist, the barrel organ is activated either by a person turning a crank, or by clockwork driven by weights or springs. The pieces of music are encoded onto wooden barrels, which are analogous to the keyboard of the traditional pipe org...
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