Mouthbow

The musical bow (bowstring or string bow) is a simple string musical instrument part of a number of South African cultures, also found in other places in the world through the result of slave trade. It consists of a flexible, usually wooden, stick 1.5 to 10 feet (0.5 to 3 m) long, and strung end to end with a taut cord, usually metal. It can be played with the hands or a wooden stick or branch. Often, it is a normal archery bow used for music.

Types of bow are different mouth-resonated string bow, earth-resonated string bow, gourd-resonated string bow, bridged string bow, spiked fiddle, and bowed trough fiddle.

Although the bow is now thought of as a weapon, it is not clear whether it was used in this way originally. A cave painting in the Trois Frères cave of southern France, dated to around 13,000 BCE, displays a bow being used as a musical instrument, so this use certainly has a long history. Musical bows are still used in a number of cultures today. It can be found as far south as Swaziland, and as far east as eastern Africa, Madagascar, and Réunion. and also outside of Africa, as in the case of berimbau, malunga (derivations of the African musical bow) or the Appalachian mouth-bow.

The usual way to make the bow sound is to pluck the string, although sometimes a subsidiary bow is used to scrape the string, much as on a violin. The Onavillu of Kerala sounds when struck with a thin stick. Unlike string instruments used in classical music, however, they do not have a built-in resonator, although resonators may be made to work with the bow in a number of ways.

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Wikipedia