A bow drill is a simple hand-operated type of

tool A tool is an object that can extend an individual's ability to modify features of the surrounding environment or help them accomplish a particular task. Although many animals use simple tools, only human beings, whose use of stone tools dates ba ...

, consisting of a rod (the ''spindle'' or ''drill shaft'') that is set in rapid rotary motion by means of a cord wrapped around it, kept taut by a bow which is pushed back and forth with one hand. This

of prehistoric origin has been used both as a drill, to make holes on solid materials such as wood, stone, bone, or teeth, and as a

fire drill A fire drill is a method of practicing how a building would be evacuated in the event of a fire or other emergencies. In most cases, the building's existing fire alarm system is activated and the building is evacuated by means of the nearest a ...

to start a fire. Bow Drill with annotations

The spindle can be held in a fixed frame, or by a hand-held block (the ''hand piece'' or ''thimble'') with a hole into which the top of the shaft is inserted. Some lubricant should be used to reduce friction between these two parts. A popular campcraft book of 1920 attributed this invention to the

Inuit Inuit (; iu, ᐃᓄᐃᑦ 'the people', singular: Inuk, , dual: Inuuk, ) are a group of culturally similar indigenous peoples inhabiting the Arctic and subarctic regions of Greenland, Labrador, Quebec, Nunavut, the Northwest Territories ...

. In Mehrgarh (Pakistan) it has been dated between the 4th-5th millennium BCE. The string of the bow is wrapped once around the spindle, so that it is tight enough not to slip during operation. In the variation called the Egyptian bow drill, the cord is wound around the shaft multiple times, or is fixed to it by a knot or a hole. The strap drill is a simpler version, where the bow is absent and the cord is kept taut by pulling the ends with both hands, while moving them left and right at the same time. In the absence of a frame, the thimble is shaped so that it can be held with the chin or mouth.

History

Bow drills with green jasper bits were used in

Mehrgarh Mehrgarh (; ur, ) is a Neolithic archaeological site (dated ) situated on the Kacchi Plain of Balochistan in Pakistan. It is located near the Bolan Pass, to the west of the Indus River and between the modern-day Pakistani cities of Quetta, ...

between the 4th and 5th millennium BC to drill holes into lapis lazuli and

carnelian Carnelian (also spelled cornelian) is a brownish-red mineral commonly used as a semi-precious gemstone. Similar to carnelian is sard, which is generally harder and darker (the difference is not rigidly defined, and the two names are often used ...

. Similar drills were found in other parts of the Indus Valley civilization and

Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...

one millennium later.

Usage

For use as a

, the shaft should have a blunt end, which is placed into a small cavity of a stationary piece of wood (the ''fireboard''). Turning the shaft with high speed and downward pressure generates heat, which eventually creates powdered charcoal and ignites it forming a small ember. For drilling, the lower end of the spindle may be fitted with a hard

drill bit Drill bits are cutting tools used in a drill to remove material to create holes, almost always of circular cross-section. Drill bits come in many sizes and shapes and can create different kinds of holes in many different materials. In order ...

that creates the hole by abrasion or cutting.

References

Kulke, Hermann & Rothermund, Dietmar (2004). ''A History of India''. Routledge. 22. .

External links

Information on constructing and using a hand drill

{{Wikibooks , Backpack Camping and Woodland Survival/Skills/Fire/Fire Starting/Bow Drill Mechanical hand tools Primitive technology Woodworking hand tools Firelighting using friction

History

Usage

See also

References

External links