Bow drill

The bow drill has been used used by ancient Sumerians and other groups to drill holes in a piece of wood, the drill stick, into another piece of wood, the hearth, with the help of a bow. The heat thusly produced by friction would set nearby dust and tinder[?] aflame.

Bow drills can also be used with a drill bit[?] to bore a hole in wood for woodworking purposes.