Bowed clavier
The bowed clavier (Bogenclavier,streichklavier or geigenwerke in German) is a keyboard instrument strung with gut strings, the tone of which is produced by a steadily revolving, well rosined cylinder powered by a foot pedal, a mechanism similar to that found in the hurdy-gurdy
The Geigenwerck was illustrated and described by Michael Praetorius in his treatise on musical instruments Syntagma Musicum II, in the section De Organograhia, published 1614-20 in Germany.
It was re-invented by Joh. Hohlfeld of Berlin in 1751. This instrument and another one of his inventions, a device that recorded keyboard improvisations in real time, were mentioned in the "Essay on the True Art of Playing Keyboard Instruments" by C. P. E. Bach.
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