Quart
The quart (abbreviation: qt) is an English unit of volume equal to a quarter gallon. Presently, three kinds of quarts remain in use: the liquid quart and dry quart of the US customary system and the imperial quart of the British imperial system. All are roughly equal to one liter. It is divided into two pints or (in the US) four cups. Historically, the exact size of the quart has varied with the different values of gallons over time and in reference to different commodities.
Name
The term comes from the Latin quartus (meaning one-quarter) via the French quart. However, although the French word quart has the same root, it frequently means something entirely different. In Canadian French in particular, the quart is called pinte,[1] whilst the pint is called chopine.[citation needed]
History
Since gallons of various sizes have historically been in use, the corresponding quarts have also existed with various sizes.
Definitions and equivalencies
US liquid quart
In the United States, all traditional length and volume measures have been legally standardized for commerce by the international yard and pound agreement of 1959, using the definition of 1 yard being exactly equal to 0.9144 meters. From this definition is derived the metric equivalencies for inches, feet, and miles, area measures, and measures of volume. The US liquid quart equals 57.75 cubic inches, which is exactly equal to 0.946352946 liters.[2][3]
| 1 US liquid quart | = | 1⁄4 | US liquid gallons |
| = | 2 | US liquid pints | |
| = | 4 | US liquid cups | |
| = | 8 | US liquid gills | |
| = | 32 | US fluid ounces | |
| = | 57.75 | cubic inches[4] | |
| ≡ | 0.946352946 | liters[3][5] | |
| ≈ | 33.307 | imperial fluid ounces |
US dry quart
In the United States, the dry quart is equal to one quarter of a US dry gallon, or exactly 1.101220942715 liters.
| 1 US dry quart | = | 1⁄32 | US bushels |
| = | 1⁄8 | US pecks | |
| = | 1⁄4 | US dry gallons | |
| = | 2 | US dry pints | |
| = | 67.200625 | cubic inches | |
| ≡ | 1.101220942715 | liters[3][5] | |
| ≈ | 38.758 | imperial fluid ounces |
Imperial quart
The imperial quart, which is used for both liquid and dry capacity, is equal to one quarter of an imperial gallon, or exactly 1.1365225 liters. In the United Kingdom goods may be sold by the quart if the equivalent metric measure is also given.[6]
| 1 imperial quart | = | 1⁄4 | imperial gallons |
| = | 2 | imperial pints | |
| = | 40 | imperial fluid ounces | |
| ≡ | 1.1365225 | liters[7][a] | |
| ≈ | 69.355 | cubic inches | |
| ≈ | 38.430 | US fluid ounces |
In French Canada, by federal law, the imperial quart is called pinte.[8][1]
Winchester quart
The Winchester quart is an archaic measure,[9] roughly equal to 2 imperial quarts or 2.25 liters. The 2.5 L bottles in which laboratory chemicals are supplied are sometimes referred to as Winchester quart bottles, although they contain slightly more than a traditional Winchester quart.
Reputed quart
The reputed quart was a measure equal to two thirds of an imperial quart (or one sixth of an imperial gallon) at about 0.7577 liters, which is approximately equal to one US fifth (0.757 liters).
The reputed quart was previously recognized as a standard size of wine bottle in the United Kingdom, and is only slightly larger than the current standard wine bottle of 0.75 L.[10][11]
Notes
References
- ^ a b Mesures Canada
- ^ "Authorized tables", United States Code, Title 15, ch. 6, subchapter I, sec. 205, accessed 19 July 2008.
- ^ a b c Guide for the Use of the International System of Units (SI)—US government publication
- ^ One US liquid gallon is defined as 231 cubic inches.
- ^ a b This has been the exact conversion since the 1964 redefinition of the liter and the 1959 redefinition of the inch.
- ^ "Weights and Measures Act 1985, Section 8". Government of the United Kingdom.
- ^ a b Text of the Units of Measurement Regulations 1995 as originally enacted or made within the United Kingdom, from legislation.gov.uk. Retrieved 3 May 2011.
- ^ Measurement Canada
- ^ Trading Standards – Weights and Measures of the City of Winchester Archived 22 January 2009 at the Wayback Machine
- ^ "Reputed, adj. (b)". Oxford English Dictionary. Retrieved 24 December 2014.
- ^ "Reputed quart". Sizes – The Online Quantinary. Retrieved 24 December 2014.
