You may be familiar with an instrument called a "jaw harp"
(sometimes refered to as a "Trump").
An ancestor of the modern-day jaw harp is called the "mouth bow."
The mouthbow is a simple instrument. It has one string, as a regular hunting bow, with a tuning peg to tighten the string to the right pitch. One end of the bow is held against the mouth to amplify the sound. The player changes the shape of his or her mouth and bends the bow to change the notes. When it is played, its notes and haunting harmonics capture and inspire the imagination.
Here are videos showing Buffy Sainte Marie playing the mouth bow.
http://www.youtube.com/watch?v=LXkM11kp_tg&list=PL8B21DAD5618900EE
The following is an excerpt from Buffy’s comments on the Mouthbow in The Buffy Sainte-Marie Songbook:
“A mouthbow is probably the oldest musical instrument in the world. It is basically a hunting bow and I guess somebody one day figured out that you can make music on a weapon.
“Mouthbows have been found all over the world among people who use handmade hunting bows and have the time to find something worth singing about. I’ve seen mouthbows from South America that were as tall as a man. Some mouthbows have a gourd attached to simplify the sound, and others have rattles tied on and they sound good when you shake them. Mouthbows have been seen in Africa, New Guinea, Borneo, Finland, Canada, and Greenwich Village. Jimmy Driftwood plays something called a picking bow made from a spinning wheel, but the ones I play are a lot lighter than a picking bow, and so flexible you can bend the bow itself.”
http://mouthbow.org/front/mouthbows/
http://mouthbow.org/front/mouthbows/how-to-make-a-mouthbow/
Jimmie Driftwood plays the mouth bow:
“A mouthbow is probably the oldest musical instrument in the world. It is basically a hunting bow and I guess somebody one day figured out that you can make music on a weapon.
“Mouthbows have been found all over the world among people who use handmade hunting bows and have the time to find something worth singing about. I’ve seen mouthbows from South America that were as tall as a man. Some mouthbows have a gourd attached to simplify the sound, and others have rattles tied on and they sound good when you shake them. Mouthbows have been seen in Africa, New Guinea, Borneo, Finland, Canada, and Greenwich Village. Jimmy Driftwood plays something called a picking bow made from a spinning wheel, but the ones I play are a lot lighter than a picking bow, and so flexible you can bend the bow itself.”
http://mouthbow.org/front/mouthbows/
http://mouthbow.org/front/mouthbows/how-to-make-a-mouthbow/
Compare the sound of the "mouth bow"
with the "jaw harp."