An innovation in 17th century technology!
The name of this instrument (also called "Arpa Anottolini" in Italian), describes a series of U shaped hooks set in its wooden neck which enable a performer to change keys relatively quickly. The hooks, adjusted by hand, shorten the length of a string; this raises the 'pitch' or sound of a note. One drawback of the hooked harp was that a performer temporarily lost use of the hand making these adjustments. By 1720, a foot pedal was invented which mechanically adjusted the hooks, allowing performers considerably more freedom - and the use of both hands at all times!.
Pedal mechanisms soon eclipsed the hooked harp in western art music traditions. However, this instrument continued to be popular among folk and street musicians in eastern Europe into the 20th century.
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