Barrel (unit)

Uncommon card · No. 90135

A barrel is one of several units of volume applied in various contexts: there are dry barrels; fluid barrels, such as the British beer barrel and American beer barrel; oil barrels, etc. For historical reasons, the volumes of some barrel units are roughly double the volumes of others; volumes in common use range approximately from 100 to 200 litres (22 to 44 imp gal; 26 to 53 US gal). In many connections, the term drum is used almost interchangeably with barrel. Since medieval times, the term barrel as a unit of measure has had various meanings throughout Europe, ranging from about 100 litres to about 1,000 litres. The name was derived in medieval times from the French baril, of unknown origin, but still in use, both in French and as derivations in many other languages, such as Italian, Polish, and Spanish. In most countries, such usage is obsolescent, having been superseded by SI units. As a result, the meaning of corresponding words and related concepts (vat, cask, keg etc.) in other languages...

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