View source for English units

{{short description|System of units formerly used in England}}
{{About|the historical development of measurement in England up to 1826|the non-metric measurement system used in the UK|Imperial units|the system currently used in the US with similar unit names|United States customary units|an overview of both UK and US non-metric units|Imperial and US customary measurement systems}}
{{DISPLAYTITLE:English units}}
{{Use British English|date=February 2020}}

'''English units''' were the [[units of measurement]] used in [[England]] up to 1826 (when they were replaced by [[Imperial units]]), which evolved as a combination of the [[Anglo-Saxons|Anglo-Saxon]] and [[Ancient Roman units of measurement|Roman]] systems of units. Various standards have applied to English units at different times, in different places, and for different applications.

Use of the term "English units" can be ambiguous, as, in addition to the meaning used in this article, it is sometimes used to refer to the units of the descendant Imperial system as well to those of the descendant system of [[United States customary units]].<ref>{{cite book |title=Marks' Standard Handbook for Mechanical Engineers|publisher=McGraw Hill|edition=11 |date=2006 |author=Eugene A. Avallone |author2=Theodore Baumeister |author3=Ali Sadegh |author4=Lionel S. Marks |isbn=978-0-07-142867-5}}</ref>

The two main sets of English units were the [[Winchester measure|Winchester Units]], used from 1495 to 1587, as affirmed by [[Henry VII of England|King Henry VII]], and the [[Exchequer Standards]], in use from 1588 to 1825, as defined by [[Queen Elizabeth I]].<ref>{{cite web|title=British Imperial System|url=https://www.britannica.com/science/British-Imperial-System|website=Encyclopædia Britannica|access-date=12 September 2016}}</ref><ref>{{cite book|last1=Hosch|first1=William L.|title=The Britannica Guide to Numbers and Measurement|date=2011|publisher=The Rosen Publishing Group (Britannica Educational Publishing)|location=New York, NY|isbn=978-1-61530-108-9|page=241|url=https://books.google.com/books?id=cuN7rH6RzikC&pg=PA241|access-date=12 September 2016}}</ref>

In England (and the British Empire), English units were replaced by Imperial units in 1824 (effective as of 1 January 1826) by a [[Weights and Measures Acts of the United Kingdom|Weights and Measures Act]], which retained many though not all of the unit names and redefined (standardised) many of the definitions. In the US, being independent from the British Empire decades before the 1824 reforms, English units were standardized and adopted (as "US Customary Units") in 1832.<ref>Barbrow, L.E. and Judson, L. V. (1976) [https://www.govinfo.gov/content/pkg/GOVPUB-C13-691a9b38e29a85d0925f4db586b60735/pdf/GOVPUB-C13-691a9b38e29a85d0925f4db586b60735.pdf ''Weights and Measures of the United States'']. National Bureau of Standards Special Publication 447. p. 5&ndash;6</ref>

==History==
Very little is known of the [[units of measurement]] used in the British Isles prior to Roman colonisation in the 1st century AD. During the Roman period, Roman Britain relied on [[Ancient Roman units of measurement]]. During the [[Anglo-Saxon England|Anglo-Saxon]] period, the North German foot of {{convert|13.2|in|mm|abbr=off}} was the nominal basis for other units of linear measurement. The foot was divided into 4 palms or 12 thumbs. A cubit was 2 feet, an elne 4 feet. The rod was 15 Anglo-Saxon feet, the furlong 10 rods. An acre was 4 rods × 40 rods, i.e. 160 square rods or 36,000 square Anglo-Saxon feet. However, Roman units continued to be used in the construction crafts, and reckoning by the [[Roman mile]] of 5,000 feet (or 8 [[Stadion (unit)|stades]]) continued, in contrast to other Germanic countries which adopted the name "mile" for a longer native length closer to the [[league (unit)|league]] (which was 3 Roman miles). From the time of [[Offa of Mercia|Offa King of Mercia]] (8th century) until 1526 the ''Saxon pound'', also known as the ''moneyers' pound'' (and later known as the [[Tower pound]]) was the fundamental unit of weight (by Offa's law, one pound of silver, by weight, was subdivided into 240 silver pennies, hence (in money) 240 pence – twenty shillings – was known as ''one pound'').

Prior to the enactment of a law known as the "[[Composition of Yards and Perches]]" ({{langx|la|Compositio ulnarum et perticarum}})<ref>{{cite book | last = Zupko | first = Ronald Edward | author-link = Ronald Edward Zupko | title = British Weights and Measures: A History from Antiquity to the Seventeenth Century | publisher=University of Wisconsin Press | year = 1977 | isbn = 978-0-299-07340-4 | pages = 20–21 | url = https://books.google.com/books?id=pWUgAQAAIAAJ}}</ref> some time between 1266 and 1303, the English system of measurement had been based on that of the [[Anglo-Saxons]], who were descended from tribes of northern [[Germany]]. The ''Compositio'' redefined the yard, foot, inch, and barleycorn to {{frac|10|11}} of their previous value.{{dubious|The 11/10 transition in c1300|date=November 2024}} However, it retained the Anglo-Saxon rod of 15 x {{frac|11|10}} feet (5.03 metres) and the acre of 4 × 40 square rods. Thus, the rod went from 5 old yards to {{frac|5|1|2}} new yards, or 15 old feet to {{frac|16|1|2}} new feet. The furlong went from 600 old feet (200 old yards) to 660 new feet (220 new yards). The acre went from 36,000 old square feet to 43,560 new square feet. Scholars have speculated that the ''Compositio'' may have represented a compromise between the two earlier systems of units, the Anglo-Saxon and the Roman.

The [[Norman conquest of England]] introduced just one new unit: the bushel.{{citation needed|date=January 2022}} [[William the Conqueror]], in one of his first legislative acts, confirmed existing Anglo-Saxon measurement, a position which was consistent with Norman policy in dealing with occupied peoples. The [[Magna Carta]] of 1215 stipulates that there should be a standard measure of volume for wine, ale and corn (the London Quarter), and for weight, but does not define these units.<ref>{{cite web |url=https://sourcebooks.fordham.edu/source/magnacarta.asp |title=The Text of Magna Carta |publisher=Fordham University}} (translated to modern English. See paragraph 35.)</ref>

Later development of the English system was by defining the units in laws and by issuing measurement standards. Standards were renewed in 1496, 1588, and 1758.<ref name=knight>{{cite book|last=Knight|first=Charles|title=The Penny magazine of the Society for the Diffusion of Useful Knowledge, Volume 9|year=1840|publisher=Society for the Diffusion of Useful Knowledge|location=London|url=https://books.google.com/books?id=-BHnAAAAMAAJ|pages=221–2|quote=In 1758 the legislature turned attention to this subject; and after some investigations on the comparative lengths of the various standards, ordered a rod to be made of brass, about 38 or 39 inches long, graduated (measured) from the Royal Society's yard: this was marked "Standard Yard, 1758," and was given into the care of the clerk of the House of Commons. For commercial purposes another bar was made, with the yard marked off from the same standard; but it had two upright fixed markers, placed exactly one yard apart, between which any commercial yard measures might be placed, in order to have their accuracy tested: it was graded in feet, one of the feet was graded in inches, and one of the inches in ten parts. This standard yardstick was kept at the Exchequer. In 1760, a copy of Bird's standard, made two years before, was constructed.}}</ref> The last ''Imperial Standard Yard'' in bronze was made in 1845; it served as the standard in the [[United Kingdom]] until the yard was redefined by the [[international yard and pound]] agreement (as 0.9144 metres) in 1959 (statutory implementation was in the [[Weights and Measures Act 1963]]). Over time, the English system had spread to other parts of the [[British Empire]].

===Timeline===
Selected excerpts from the bibliography of ''Marks and Marking of Weights and Measures of the British Isles''<ref>{{cite book|last1=Ricketts|first1=Carl|title=Marks and Marking of Weights and Measures of the British Isles|date=1996|publisher=Devon Design and Print|location=Taunton, Somerset|isbn=0-9528533-0-2|url=https://books.google.com/books?id=a8UmAQAACAAJ}}</ref>
*1215 Magna Carta — the earliest statutory declaration for uniformity of weights and measures
*1335 8 & 9 Edw. 3. c. 1{{clarify|date=June 2024}} — First statutory reference describing goods as avoirdupois
*1414 [[2 Hen. 5. Stat. 2]]. c. 4 — First statutory mention of the Troy pound
*1495 [[12 Hen. 7]]. c. 5 — New Exchequer standards were constructed, including Winchester capacity measures defined by Troy weight of their content of threshed wheat by stricken (i.e. level) measure (first statutory mention of Troy weight as standard weight for bullion, bread, spices etc.).<ref>{{Cite book |chapter-url=https://archive.org/details/statutesatlarge23britgoog/page/78/mode/2up |chapter=Cap. V: For weights and measures |page=78 |title=The Statutes at Large: from the first year of King Richard III to the thirty-first Year of King Henry VIII |publisher=Charles Bathurst |year=1765 |editor-last=Pickering |editor-first=Danby |editor-link=Danby Pickering |volume=4 |location=Cambridge}}</ref>
*1527 Hen VIII — Abolished the Tower pound
*1531 [[23 Hen. 8]]. c. 4 — Barrel to contain 36 gallons of beer or 32 of ale; kilderkin is half of this; firkin is half again.<ref>{{Cite book  |page=220 |chapter-url=https://archive.org/details/statutesatlarge23britgoog/page/219/mode/1up |chapter=Cap. IV. An act concerning making of new barrels, kilderkins and other vessels |title=The Statutes at Large: from the first year of King Richard III to the thirty-first Year of King Henry VIII |publisher=Charles Bathurst |year=1765 |editor-last=Pickering |editor-first=Danby |editor-link=Danby Pickering |volume=4 |location=Cambridge |quote=Beef, pork, mutton and veal shall be sold by weight called {{notatypo|''Haver-de-pois''}}}}</ref>
*1532 [[24 Hen. 8]]. c. 3 — First statutory references to use of avoirdupois weight.<ref>{{Cite book  |page=251 |chapter-url=https://archive.org/details/statutesatlarge23britgoog/page/251/mode/1up |chapter=Cap. III |title=The Statutes at Large: from the first year of King Richard III to the thirty-first Year of King Henry VIII |publisher=Charles Bathurst |year=1765 |editor-last=Pickering |editor-first=Danby |editor-link=Danby Pickering |volume=4 |location=Cambridge |quote=Beef, pork, mutton and veal shall be sold by weight called {{notatypo|''Haver-de-pois''}}}}</ref>
*1536 [[28 Hen. 8]]. c. 4 — Added the tierce (41 gallons)
*1588 (Elizabeth I) — A new series of Avoirdupois standard bronze weights (bell-shaped from 56&nbsp;lb to 2&nbsp;lb and flat-pile from 8&nbsp;lb to a dram), with new Troy standard weights in nested cups, from 256 oz to {{frac|1|8}} oz in a binary progression.
*1601–1602 — Standard bushels and gallons were constructed based on the standards of Henry VII and a new series of capacity measures were issued.
*1660 [[12 Cha. 2]]. c. 24 — Barrel of beer to be 36 gallons, taken by the gauge of the Exchequer standard of the ale quart; barrel of ale to be 32 gallons; all other liquors retailed to be sold by the wine gallon
*1689 [[1 Will. & Mar.]] c. 24 — Barrels of beer and ale outside London to contain 34 gallons
*1695 7 Will. 3. c. 24 (I) — Irish Act about grain measures decreed: unit of measure to be Henry VIII's gallon as confirmed by Elizabeth I; i.e. {{frac|272|1|4}} cubic inches; standard measures of the barrel (32 gallons), half-barrel (16 gallons), bushel (8), peck (2), and gallon lodged in the Irish Exchequer; and copies were provided in every county, city, town, etc.
*1696 [[8 & 9 Will. 3]]. c. 22 — Size of Winchester bushel "every round bushel with a plain and even bottom being {{frac|18|1|2}}″ wide throughout and 8″ deep" (i.e. a dry measure of 2150 in<sup>3</sup> per gallon).
*1706 [[6 Ann.]] c. 11 — ''Act of Union'' decreed the weights and measures of England to be applied in Scotland, whose burgs (towns) were to take charge of the duplicates of the English Standards sent to them.
*1706 [[6 Ann.]] c. 27 — Wine gallon to be a cylindrical vessel with an even bottom 7″ diameter throughout and 6″ deep from top to bottom of the inside, or holding 231 in<sup>3</sup> and no more.
*1713 [[12 Ann.]] c. 17 — The legal coal bushel to be round with a plain and even bottom, {{frac|19|1|2}} inches from outside to outside and to hold 1 Winchester bushel and 1 quart of water.
*1718 [[5 Geo. 1]]. c. 18 — Decreed Scots Pint to be exactly 103 in<sup>3</sup>.
*1803 [[43 Geo. 3]]. c. 151 — Referred to wine bottles making about 5 to the wine gallon (i.e. Reputed Quarts)
*1824 [[5 Geo. 4]]. c. 74 — [[Weights and Measures Act 1824]] completely reorganized British metrology and established Imperial weights and measures; defined the yard, troy and avoirdupois pounds and the gallon (as the standard measure for liquids and dry goods not measured by heaped measure), and provided for a 'brass' standard gallon to be constructed.
*1825 [[6 Geo. 4]]. c. 12 — Delayed introduction of Imperial weights and measures from 1 May 1825 to 1 January 1826.
*1835 [[5 & 6 Will. 4]]. c. 63 — [[Weights and Measures Act 1835]] abolished local and customary measures, including the Winchester bushel; made heaped measure illegal; required trade to be carried out by avoirdupois weight only, except for bullion, gems and drugs (which were to be sold by troy weight instead); decreed that all forms of coal were to be sold by weight and not measure; legalised the 'stone' as {{convert|14|lb|kg|abbr=on}}, the 'hundredweight' as {{convert|112|lb|kg|abbr=on}}, and the ([[long ton|long]]) ton as 20 hundredweight, or {{convert|2240|lb|kg|abbr=on}}.
*1853 [[16 & 17 Vict.]] c. 29 — Permitted the use of decimal bullion weights.
*1866 [[29 & 30 Vict.]] c. 82 — [[Standards of Weights, Measures, and Coinage Act 1866]] transferred all duties and standards from the Exchequer to the newly created Standards Department of the Board of Trade.
*1878 [[41 & 42 Vict.]] c. 49 — [[Weights and Measures Act 1878]] defined the Imperial standard yard and pound; enumerated the secondary standards of measure and weight derived from the Imperial standards; required all trade by weight or measure to be in terms of one of the Imperial weights or measures or some multiple part thereof; abolished the Troy pound.
*1963 c. 31 — [[Weights and Measures Act 1963]] abolished the chaldron of coal, the fluid drachm and minim (effective 1 February 1971), discontinued the use of the quarter, abolished the use of the bushel and peck, and abolished the pennyweight (from 31 January 1969).

== Length ==
{{more citations needed|section|date=March 2025}}
[[File:English Length Units Graph.svg|thumb|right|Chart showing the (sometimes approximate) relationships between assorted historical distance measures]]
{{hatnote|SI conversions given are approximate, except where defined or documented by the [[International yard and pound]] agreement of 1959}}
{{mw-datatable}}
{| class="wikitable sortable mw-datatable static-row-numbers" style="text-left;"
|+ Table of equivalences
|-
! English&nbsp;unit !! [[International System of Units|SI]]&nbsp;(metric) !!class="unsortable"|Traditional definition{{citation needed|date=March 2025}}
|-
| [[Poppy seed|Poppyseed]] || 2.12 or 1.69&nbsp;mm || = {{frac|1|4}} or {{frac|1|5}} of a barleycorn<ref>{{OED|poppyseed}}</ref>
|-
| [[Line (unit)|Line]] || 2.12&nbsp;mm || = {{frac|1|4}} of a barleycorn,<ref name=Klein>{{cite book|title=The world of measurements: masterpieces, mysteries and muddles of metrology|isbn=0-671-21565-5|author=H. Arthur Klein|publisher=Simon and Schuster|location=New York|year=1974|page=[https://archive.org/details/worldofmeasureme0000klei/page/63 63]|url=https://archive.org/details/worldofmeasureme0000klei/page/63}}</ref> (thus {{frac|1|12}} of an inch).
|-
| [[Barleycorn (unit)|Barleycorn]] || 8.47&nbsp;mm || = {{fract|1|3}} of an inch, the notional base unit under the ''Composition of Yards and Perches''.
|-
|  [[digit (unit)|Digit]] || 19.05&nbsp;mm || =  {{frac|3|4}} inch
|-
| [[finger (unit)|Finger]] || 22.23&nbsp;mm || = {{frac|7|8}} inch
|-
| [[Inch]] || 25.4&nbsp;mm || 3 barleycorns (the historical legal definition{{citation needed|date=March 2025}})
|-
| [[nail (unit)|Nail (cloth)]] || 57.15&nbsp;mm || 3 digits = {{frac|2|1|4}} inches = {{frac|1|16}} yard
|-
| [[palm (unit)|Palm]]  || 76.2&nbsp;mm || 3&nbsp;inches
|-
| [[hand (unit)|Hand]] || 101.6&nbsp;mm || 4&nbsp;inches
|-
| [[Shaftment]] || 165&nbsp;mm&nbsp;or&nbsp;152&nbsp;mm || Width of the hand and outstretched thumb, {{frac|6|1|2}} inches before 12th century, 6 thereafter<ref>{{cite web |url=https://www.unc.edu/~rowlett/units/dictS.html |title=How Many? A Dictionary of Units of Measurement |publisher=University of North Carolina |first=Russ |last=Rowlett |access-date=17 January 2022 |archive-url=https://web.archive.org/web/20140726152208/https://www.unc.edu/~rowlett/units/dictS.html |archive-date=26 July 2014 }}</ref>
|-
| [[Link (unit)|Link]] || 201.2&nbsp;mm || 7.92&nbsp;inches or one 100th of a [[chain (unit)|chain]].<ref>[http://www.merriam-webster.com/dictionary/link Merriam Webster Online Dictionary, Link definition]</ref> (A modern Indian surveyor's chain has 200{{nbsp}}mm links.)
|-
| [[span (unit)|Span]] || 228.6&nbsp;mm || Width of the outstretched hand, from the tip of the thumb to the tip of the little finger: 9&nbsp;inches (= 3 palms).
|-
| [[foot (unit)|Foot]] || 304.8&nbsp;mm ||  Prior to the Anglo-Saxon invasions, the Roman foot of {{convert|11.65|in|mm|0}} was used. The Anglo-Saxons introduced a North-German foot of {{convert|13.2|in|mm|0}}, divided into 4 palms or 12 thumbs, while the Roman foot continued to be used in the construction crafts.{{citation needed|date=March 2025}} In the late 13th century, the modern foot of 304.8&nbsp;mm was introduced, equal to exactly {{frac|10|11}} Anglo-Saxon foot.{{citation needed|date=March 2025}}
|-
| [[Cubit]] || 457.2&nbsp;mm || From fingertips to elbow, 18&nbsp;inches.
|-
| [[Yard]] || 0.914 m || 3 feet = 36&nbsp;inches, the practical base unit, defined as the length of the [[prototype (metrology)|prototype]] bar held by the Crown or [[Exchequer]]. <!-- removed uncited and incredible claim that it is the same length as an [[ulna]] -->
|-
| [[ell (unit)|Ell]] || 1.143 m || From fingertip of outstretched arm to opposite shoulder, 20 nails = {{frac|1|1|4}} yard or 45&nbsp;inches. Mostly for measuring cloth.
|-
| [[Fathom]] || 1.829 m || 6 feet, distance between arms outstretched, from fingertip to fingertip, on a 6-foot-tall person.
|-
| [[rod (unit)|Rod]] || 5.0292 m || Also called a [[Perch (unit)|perch]] or [[Pole (unit)|pole]]: a measure used for surveying land and in architecture. The length of the rod (then called perch) was declared to be {{frac|16|1|2}} feet or {{frac|5|1|2}} yards in the ''Composition of Yards and Perches''. The square pole is commonly used as a measurement for [[Allotment garden]]s. (See also [[rod (unit)#Area and volume|perch as an area and a volume unit]].)
|-
| [[chain (unit)|Chain]] || 20.116 m || Four linear ''rods''. Named after the length of [[surveyor's chain]] used to measure distances until quite recently. Any of several actual chains used for land surveying and divided in links. [[Gunter's chain]], introduced in the 17th century, is {{convert|66|feet|abbr=off|sigfig=3}}.
|-
| [[Furlong]] || 201.168 m ||  Notionally the distance a plough team could furrow without rest, but actually a measure of 40 rods or 600 feet prior to the ''Composition of Yards and Perches''; 40 rods or 660 feet since then. (See also the Ancient Greek {{transliteration|grc|[[stadion (unit)|stadion]]}} or 'stade'.)
|-
| [[Mile]] || 1.61&nbsp;km ||  5280 feet or 1760 yards. Originally the Roman mile, 1000 [[Pace (unit)|paces]], later reckoned as 5000 feet, but adjusted to 5280 feet in 1593 to account for the differences introduced to these methods of reckoning by the ''Composition of Yards and Perches''.
|-
| [[League (unit)|League]] || 4.83&nbsp;km || Notionally an hour's march, but usually reckoned as three [[mile]]s. Approximate length of the traditional "mile" in German and Scandinavian countries.
|}

== Area ==
{{hatnote|SI conversions given are approximate}}
{| class="wikitable sortable mw-datatable static-row-numbers" style="text-left;"
|+ Table of equivalences
! English unit !! [[International System of Units|SI]] ("metric") !!Relationship
|-
| [[Rod (unit)#Area and volume|Square rod]] || 25.29 [[square meter|m<sup>2</sup>]] || 30.25 square yards. A square rod is also known as a square pole or a square perch. Sometimes the word 'square' is omitted when the context clearly indicates that the subject is area, notably so in the case of British [[allotment gardens]].
|-
| [[Rood (unit)|Rood]] || 1,012 m<sup>2</sup> || One quarter of an [[acre]]; one 'furlong' in length by one 'rod' in width; 40 square 'rods'. The rood was sometimes called an acre itself in many ancient contexts.{{citation needed|date=October 2021}}
|-
| [[Acre]] ||4,047 m<sup>2</sup> ||An area of land one chain (four rods) wide by one furlong in length. As the traditional furlong could vary in length from country to country, so did the acre. In England an acre was {{convert|4,840|sqyd}}, in [[Scotland]] {{convert|6,150|sqyd}} and in Ireland {{convert|7,840|sqyd}}. It is a Saxon unit, meaning "field".
|-
| [[Bovate]], [[Oxgang]] || 6 ha ||The area that one ox can plough in a single year. Approximately 15 acres or one eighth of a [[carucate]].
|-
| [[Virgate]] || 12 ha ||The area that a pair of oxen can plough in a single year. Approximately 30 acres (also called ''yard land'').<!--yardland, barony, -->
|-
| [[Carucate]] || 49 ha || The area that can be ploughed by one eight-oxen team in a single year (also called a ''plough'' or ''carve''). Approximately 120 acres.
|}

=== Administrative units ===
; [[Hide (unit)|Hide]]: four to eight ''bovates''. A unit of yield, rather than area, it measured the amount of land able to support a single [[household]] for agricultural and taxation purposes.
; [[Knight's fee]]: five hides. A ''knight's fee'' was expected to produce one fully equipped soldier for a [[knight]]'s retinue in times of war.
; [[Hundred (division)|Hundred]] or [[wapentake]]: 100 ''hides'' grouped for administrative purposes.

== Volume ==
<!--very incomplete-->
{{more citations needed section|date=August 2017}}
Many measures of [[Volume#Related terms|capacity]] were understood as fractions or multiples of a [[gallon]]. For example, a quart is a quarter of a gallon, and a pint is half of a quart, or an eighth of a gallon. These ratios applied regardless of the specific size of the gallon. Not only did the definition of the gallon change over time, but there were several different kinds of gallon, which existed at the same time. For example, a [[wine gallon]] with a volume of 231 cubic inches (the basis of the [[U.S. gallon]]) and an [[ale gallon]] of 282 cubic inches, were commonly used for many decades prior to the establishment of the [[gallon#Imperial gallon|imperial gallon]]. In other words, a pint of ale and a pint of wine were not the same size. On the other hand, some measures{{snd}} such as the [[fluid ounce]]{{snd}} were not defined as a fraction of a gallon. For that reason, it is not always possible to give accurate definitions of units such as pints or quarts, in terms of ounces, prior to the establishment of the imperial gallon.

===General liquid measures===
{{hatnote|SI conversions given are approximate}}
{| class="wikitable"
|+ Table of equivalences
!Name!!Approx<br>SI<br>equiv.!!Notes
|-
| [[Minim (unit)|Minim]] || 0.06{{nbsp}}[[milliliter|mL]] || Also known as a [[drop (unit)|drop]]. {{efn|The volume of a drop was not then and is not now well defined: it depends on the device and technique used to produce the drop, on the strength of the gravitational field, and on the [[viscosity]], density, and the [[surface tension]] of the liquid.<ref name="phisics">{{cite web 
| title = Drop – size
| publisher = Physics and Astronomy Online
| url = http://www.physlink.com/education/askexperts/ae681.cfm
| access-date = 2010-03-29
}}</ref>}}
|-
|[[Dram (unit)|Dram]] ||3.55 mL ||60 [[minim (unit)|minim]]s or 'drops' or {{frac|8}} [[fluid ounce]] (fl oz). See also [[drachm]].
|-
|[[Teaspoon]] ||5 mL || 80 minim or ''drops'' or {{frac|6}} fl oz
|-
|[[Tablespoon]] || 15 mL || 4 dram (240 minim or drops), 3 teaspoons, or {{frac|2}} fl oz
|- 
|Jack || 71 mL || {{frac|2}} Gill. This is not a traditional measure.
|-
|[[Gill (volume)|Gill]] || 142 mL || {{frac|4}} pint, or {{frac|32}} gallon, in some dialects {{frac|2}} pint. Pronounced as "Jill"
|-
<!-- Please do not add [[cup (unit)]] as this is a US Customary Unit. It was not an _English_ Unit  -->
| [[Pint]] ||568 mL || {{frac|8}} gallon <!-- Yes, the metric conversion is correct for the _English_ pint, which is not the same as a US pint -->
|-
|[[Quart]] || 1.136 [[litre]] ||2 pints or {{frac|4}} gallon
|-
|[[Pottle (unit)|Pottle]] || 2.272 L || 2 quarts or {{frac|2}} gallon
|-
|[[Gallon]] ||4.544 L ||8 pints
|}

Liquid measures as binary submultiples of their respective gallons (ale or wine):
{| class="wikitable"
|-
! &nbsp; !! jack !! gill !! pint !! quart !! pottle !! gallon 
! 2<sup>''n''</sup> gal.
|-
!1 jack =
||1||{{frac|2}}||{{frac|8}}||{{frac|16}}||{{frac|32}}||{{frac|64}}
|–6
|-
!1 gill =
|2|||1||{{frac|4}}||{{frac|8}}||{{frac|16}}||{{frac|32}}
|–5
|-
!1 pint =
|8||4|||1||{{frac|2}}||{{frac|4}}||{{frac|8}}
|–3
|-
!1 quart =
|16||8||2|||1||{{frac|2}}||{{frac|4}}
|–2
|-
!1 pottle =
|32||16||4||2|||1||{{frac|2}}
|–1
|-
!1 gallon =
|64||32||8||4||2|||1
|0
|}

===Wine===
{{Main|English wine cask units}}
Wine is traditionally measured based on the ''[[wine gallon]]'' and its related units. Other liquids such as brandy, spirits, mead, cider, vinegar, oil, honey, and so on, were also measured and sold in these units.<ref name="Kirkby 1735">{{Cite book |title=Arithmetical Institutions |last=Kirkby |first=Rev. Mr. John |publisher=Motte and Bathurst |year=1735 |location=London |at=Part II, page 14 |url=https://archive.org/stream/arithmeticalins00kirkgoog#page/n76/mode/1up}}</ref>

The wine gallon was re-established by [[Anne, Queen of Great Britain|Queen Anne]] in 1707 after a 1688 survey found the [[Exchequer]] no longer possessed the necessary standard but had instead been depending on a copy held by the [[Guildhall, London|Guildhall]].{{citation needed|date=August 2017}} Defined as 231 [[cubic inch]]es, it differs from the later [[Imperial units|imperial gallon]], but is equal to the [[United States customary units|United States customary gallon]].
;[[Rundlet]]: 18 wine gallons or {{frac|7}} wine pipe
;[[Barrel (unit)|Wine barrel]]: 31.5 wine gallons or {{frac|2}} wine hogshead
;[[English wine cask units#Tierce|Tierce]]: 42 wine gallons, {{frac|2}} puncheon or {{frac|3}} wine pipe
;[[Hogshead|Wine hogshead]]: 2 wine barrels, 63 wine gallons<ref>{{cite book |last=Unwin |first=Tim |title=Wine and the Vine |url=https://archive.org/details/winevinehistoric00unwi |url-access=limited |year=1991 |publisher=Routledge |location=London |isbn=0-415-14416-7 |page=[https://archive.org/details/winevinehistoric00unwi/page/n388 364]}}</ref> or {{frac|4}} wine tun
;[[English wine cask units#puncheon|Puncheon]] or tertian: 2 tierce, 84 wine gallons or {{frac|3}} wine tun
;[[Pipe (unit)|Wine pipe]] or butt: 2 wine hogshead, 3 tierce, 7 roundlet or 126 wine gallons
;[[Tun (unit)|Wine tun]]: 2 wine pipe, 3 puncheon or 252 wine gallons

{{English wine casks}}

===Ale and beer===
{{Main|English brewery cask units}}
;Pin: 4.5 gallons or {{frac|8}} beer barrel
;[[English brewery cask units#Firkin|Firkin]]: 2 pins, 9 gallons (ale, beer or goods) or {{frac|4}} beer barrel
;[[Kilderkin]]: 2 firkins, 18 gallons or {{frac|2}} beer barrel
;[[Barrel (unit)|Beer barrel]]: 2 kilderkins, 36 gallons or {{frac|2|3}} beer hogshead
;[[Hogshead|Beer hogshead]]: 3 kilderkins, 54 gallons or 1.5 beer barrels
;[[Pipe (unit)|Beer pipe]] or butt: 2 beer hogsheads, 3 beer barrels or 108 gallons
;[[Tun (unit)|Beer tun]]: 2 beer pipes or 216 gallons

{{English brewery casks}}

===Grain and dry goods===

The [[Winchester measure]], also known as the corn measure, centered on the [[bushel]] of approximately 2,150.42 cubic inches, which had been in use with only minor modifications since at least the late 15th century. The word ''corn'' at that time referred to all types of grain. The corn measure was used to measure and sell many types of dry goods, such as grain, salt, ore, and oysters.<ref name="Trusler 1786">{{Cite book |chapter-url=http://quod.lib.umich.edu/e/ecco/004859210.0001.000/1:10.14?rgn=div2;view=fulltext |chapter=Tables of measures and weights. |title=The London Adviser and Guide |last=Trusler |first= John |year=1786 |location=London |page=188 |via=Eighteenth Century Collections Online, Text Creation Partnership |url-status=live |archive-url= https://web.archive.org/web/20230606082457/https://quod.lib.umich.edu/e/ecco/004859210.0001.000/1:10.14?rgn=div2;view=fulltext |archive-date= Jun 6, 2023 }}</ref>

However, in practice, such goods were often sold by weight. For example, it might be agreed by local custom that a bushel of wheat should weigh 60 pounds, or a bushel of oats should weigh 33 pounds. The goods would be measured out by volume, and then weighed, and the buyer would pay more or less depending on the actual weight. This practice of specifying [[Bushel#Weight|bushels in weight]] for each commodity continues today. This was not always the case though, and even the same market that sold wheat and oats by weight might sell barley simply by volume. In fact, the entire system was not well standardized. A sixteenth of a bushel might be called a ''pottle'', ''hoop'', ''beatment'', or ''quartern'', in towns only a short distance apart. In some places potatoes might be sold by the firkin—usually a liquid measure—with one town defining a firkin as 3 bushels, and the next town as 2 1/2 bushels.<ref name="Bailey 1810">{{Cite book |title=General View of the Agriculture of the County of Durham, with Observations on the Means of its Improvement |last=Bailey |first=John |publisher=Richard Phillips |year=1810 |location=London |url=https://archive.org/details/bub_gb_o53QCG8cieIC|page=[https://archive.org/details/bub_gb_o53QCG8cieIC/page/n311 283] }}</ref>

The pint was the smallest unit in the corn measure. The corn gallon, one eighth of a bushel, was approximately 268.8 cubic inches. Most of the units associated with the corn measure were binary (sub)multiples of the bushel:<ref name="Kirkby 1735" /><ref name="Trusler 1786" />
{| class="wikitable"
|-
! &nbsp; !! pint !! quart !! pottle !! gallon !! peck !! kenning !! bushel !! strike !! coomb !! seam
! 2<sup>''n''</sup> gal.
|-
!1 pint =
|1||{{frac|2}}||{{frac|4}}||{{frac|8}}||{{frac|16}}||{{frac|32}}||{{frac|64}}||{{frac|128}}||{{frac|256}}||{{frac|512}}
|–3
|-
!1 quart =
|2|||1||{{frac|2}}||{{frac|4}}||{{frac|8}}||{{frac|16}}||{{frac|32}}||{{frac|64}}||{{frac|128}}||{{frac|256}}
|–2
|-
!1 pottle =
|4||2|||1||{{frac|2}}||{{frac|4}}||{{frac|8}}||{{frac|16}}||{{frac|32}}||{{frac|64}}||{{frac|128}}
|–1
|-
!1 gallon =
|8||4||2|||1||{{frac|2}}||{{frac|4}}||{{frac|8}}||{{frac|16}}||{{frac|32}}||{{frac|64}}
|0
|-
!1 peck =
|16||8||4||2|||1||{{frac|2}}||{{frac|4}}||{{frac|8}}||{{frac|16}}||{{frac|32}}
|1
|-
!1 kenning =
|32||16||8||4||2||1||{{frac|2}}||{{frac|4}}||{{frac|8}}||{{frac|16}}
|2
|-
!1 bushel =
|64||32||16||8||4||2||1||{{frac|2}}||{{frac|4}}||{{frac|8}}
|3
|-
!1 strike =
|128||64||32||16||8||4||2||1||{{frac|2}}||{{frac|4}}
|4
|-
!1 coomb =
|256||128||64||32||16||8||4||2||1||{{frac|2}}
|5
|-
!1 seam =
|512||256||128||64||32||16||8||4||2||1
|6
|-
|}

Other units included the ''wey'' (6 or sometimes 5 seams or quarters), and the ''last'' (10 seams or quarters).<ref name="Kirkby 1735" /><ref name="Trusler 1786" />

===Specific goods===
;[[Perch (volume)|Perch]]: 24.75&nbsp;[[cubic foot|cubic feet]] of dry stone, derived from the more commonly known perch, a unit of length equal to 16.5 feet.<ref>Blocksma, Mary. Reading the Numbers. New York: Penguin Books, 1989.</ref>
;[[Cord (volume)|Cord]]: 128 cubic feet of firewood, a stack of firewood 4&nbsp;ft × 4&nbsp;ft × 8&nbsp;ft<ref>{{cite book|title=[[Oxford English Dictionary]]|publisher=Oxford University Press|location=Oxford, England|year=1989|edition=2|chapter=cord, n <sup>1</sup>|quote= from [[Richard Boyle, 1st Earl of Cork|Richard Boyle]], 1616}}</ref>

===Chemistry===
;Fluid-grain: The volume of 1 [[Grain (unit)|grain]] of distilled water at 62&nbsp;°F, 30 [[Inch of mercury|inHg]] pressure.<ref>{{cite book|title=[[Chemical arithmetic]]|author=W. Dittmar |publisher=Glasgow, William Hodge & Co|location=Glasgow|year=1890|edition=1|page=72}}</ref>

At that reference, water has a density of ≃ 0.9988{{frac|g|ml}} (438.0{{sfrac|grain|[[Fluid ounce|imp fl oz]]}} or 1.001{{sfrac|oz<sub>av</sub>|imp fl oz}}), and thus:
:= 1.096 [[minim (unit)|imperial minim]]<ref>{{sfrac|480 minim<sub>imp</sub>/imp fl oz|438 gn/imp fl oz}}</ref> = .06488 ml or approximately a ''[[drop (volume)|drop]]''.

== Weight ==
[[File:English mass units graph.svg|thumb|right|400px|Chart showing the relationships of weight measures]]
The [[Avoirdupois]], [[Troy weight|Troy]] and [[Apothecaries' system of mass|Apothecary]] systems of weights all shared the same finest unit, the [[grain (measure)|grain]]; however, they differ as to the number of grains there are in a dram, ounce and [[pound (mass)|pound]]. This grain was legally defined as the weight of a grain seed from the middle of an ear of [[barley]]. There also was a smaller ''wheat grain'', said to be {{frac|3|4}} (barley) grains or about 48.6 milligrams.

The avoirdupois pound was eventually standardised as 7,000 grains and was used for all products not subject to Apothecaries's or Tower weight.<ref>{{cite book
 | last =  Zupko
 | first =Ronald Edward
 | title =A Dictionary of Weights and Measures for the British Isles
 | publisher =American Philosophical Society
 | date =1985
 | location =Independence Square Philadelphia 
 | url =https://archive.org/details/bub_gb_0l_k-XMIiQIC
 | page =  [https://archive.org/details/bub_gb_0l_k-XMIiQIC/page/n349 315]
 | isbn =978-0-87169-168-2
 }}</ref>

=== Avoirdupois ===
<!-- linked from redirect [[Clove unit]] -->
{{Main| Avoirdupois}}
{| class="wikitable"
|+ Equivalents
|-
! English unit !! SI ('Metric') !! Relationship
|-
|[[grain (measure)|Grain]] (gr)  || ≈64.80&nbsp;mg || {{frac|1|7000}} of a pound
|-
| [[Dram (unit)|Dram]]/drachm (dr) || ≈1.772&nbsp;g || sixteenth of an ounce (possibly originated as the weight of silver in Ancient Greek coin [[Ancient drachma|drachma]])
|-
| [[Ounce]] (oz) || ≈28.35&nbsp;g || 1&nbsp;oz = 16 dr = 437.5 grains
|-
| [[pound (mass)|Pound]] (lb) || ≈453.6&nbsp;g || 1&nbsp;lb = 16 oz = 7000 grains ('lb' is an abbreviation for the [[Ancient Roman units of measurement|Ancient Roman unit]] {{lang|la|[[Ancient Roman units of measurement#Weight|libra]]}})
|-
| [[stone (unit)|Stone]] (st) || 6.35&nbsp;kg || 1 st = 14&nbsp;lb (see [[Stone (unit)]] for other values)
|-
| Quarter (qr) || 12.7&nbsp;kg || 1 qr = {{frac|1|4}} cwt, or 2 st, or 28&nbsp;lb
|-
| [[Hundredweight]] (cwt) || 50.8&nbsp;kg || 1 cwt = 112&nbsp;lb, or 8 st
|-
| [[Ton]] || 1.016 [[tonne]] || 1 ton = 20 cwt, or 2240&nbsp;lb
|-
| [[nail (unit)|Nail]] || 3.175&nbsp;kg || 1 nail = {{frac|1|16}} cwt = 7&nbsp;lb
|-
| '''Clove''' || ? || 7&nbsp;lb (wool) or 8&nbsp;lb (cheese) {{citation needed|date=October 2021}}
|-
| [[Tod (unit)|Tod]] || 12.7&nbsp;kg || 1 tod = 2 st = {{frac|1|4}} cwt
|}

=== Troy and Tower ===
The Troy and Tower pounds and their subdivisions were used for coins and precious metals. The Tower pound, which was based upon an earlier Anglo-Saxon pound, was replaced by the Troy pound when a proclamation dated 1526 required the Troy pound to be used for mint purposes instead of the Tower pound.<ref>A proclamation of Henry VIII, 5 November 1526. Proclamation 112 in Paul L. Hughes and James F. Larkin, editors. ''Tudor Royal Proclamations''. Volume 1. New Haven: Yale University Press,1964.[http://www.sizes.com/units/pound_tower.htm]</ref> No standards of the Tower pound are known to have survived.<ref>R. D. Connor and A. D. C. Simpson.''Weights and Measures in Scotland. A European Perspective''.National Museums of Scotland and Tuckwell Press, 2004, page 116, quoting from H. W. Chisholm, Seventh Annual Report of the Warden for the Standards..for 1872-73 (London, 1873), quoting from 1864 House of Commons Paper.[http://www.sizes.com/units/pound_tower.htm]</ref>

Established in the 8th century by [[Offa of Mercia]], a [[pound sterling]] (or "pound of sterlings"<ref name="Entry 189985">{{cite encyclopedia |quote=sterling, n.1 and adj.|dictionary=OED Online |date=December 2011 |publisher=Oxford University Press |url=http://www.oed.com/viewdictionaryentry/Entry/189985 |title=Entry 189985 |access-date=28 February 2012 |archive-date=25 June 2015 |archive-url=https://web.archive.org/web/20150625230025/http://www.oed.com/viewdictionaryentry/Entry/189985 }}</ref>) was that weight of [[sterling silver]] sufficient to make 240 [[silver penny|silver pennies]].<ref>{{cite encyclopedia|last=Naismith |first=Rory |title= Coinage|page=330 |year=2014b|editor1-first= Michael|editor1-last= Lapidge|editor2-first= John|editor2-last= Blair|editor3-first= Simon|editor3-last= Keynes |editor4-first= Donald|editor4-last= Scragg |encyclopedia=The Wiley Blackwell Encyclopedia of Anglo-Saxon England|edition=Second|location=Chichester, UK|publisher= Blackwell Publishing|isbn=978-0-470-65632-7}}</ref>

==== Troy ====
{{main|Troy weight}}
; [[grain (measure)|Grain]] (gr) : = 64.79891&nbsp;mg
; [[Pennyweight]] (dwt) : 24 gr ≈ 1.56 g
; [[Troy ounce|Ounce]] (oz t) : 20 dwt = 480 gr ≈ 31.1<!--035--> g
; [[pound (mass)#Troy pound|Pound]] (lb t) : 12 oz t = 5760 gr ≈ 373<!--.242--> g
; [[mark (weight)|Mark]]: 8 oz t

==== Tower ====
; [[grain (measure)|Grain]] (gr) : = {{frac|45|64}} gr t ≈ 45.6&nbsp;mg
; [[Pennyweight]] (dwt) : 32 gr T = {{frac|22|1|2}} gr t ≈ 1.46 g
; Tower ounce : 20 dwt T = 640 gr T = {{frac|18|3|4}} dwt t = 450 gr t ≈ 29.2 g
; [[Tower pound]] : 12 oz T = 240 dwt T = 7680 gr T = 225 dwt t = 5400 gr t ≈ 350 g
; [[mark (weight)|Mark]]: 8 oz T ≈ 233 g

=== Apothecary ===
{{main|Apothecaries' system}}
; [[grain (measure)|Grain]] (gr) : = 64.79891&nbsp;mg
; [[Apothecaries' system|Scruple]] (s ap) : 20 gr
; [[Dram (unit)|Dram]] (dr ap) : 3 s ap = 60 gr
; [[Ounce]] (oz ap) : 8 dr ap = 480 gr
; [[pound (mass)|Pound]] (lb ap) : 5760 gr = 1&nbsp;lb t

=== Others ===
<!--compare
; Roman libra : ≈ 326–327.25 g ≈ 5031–5050 gr—5000 gr ≈ 324 g (× {{frac|16|12}} = 435–436 g)
; Charlemagne livre : ≈ 367.5 g ≈ 5671 gr (× {{frac|16|12}} = 490 g)
; Cologne pfund : > 467 g ≈ 1 London pound + 1 g
-->
; Merchants/Mercantile pound : 15 oz tower = 6750 gr <!--(about 1270–1330)--> ≈ 437.4 g
; London/Mercantile pound : 15 oz troy = 16 oz tower = 7200 gr ≈ 466.6 g
; Mercantile stone : 12&nbsp;lb L ≈ 5.6&nbsp;kg <!--[[1303]]-->
<!--; Wool pound : 6992 gr ≈ 1 lb ≈ 453 g-->
; Butcher's stone : 8&nbsp;lb ≈ 3.63&nbsp;kg
; Sack : 26 st = 364&nbsp;lb ≈ 165&nbsp;kg<!--wool-->
: The [[Carat (unit)|carat]] was once specified as four grains in the English-speaking world.
: Some local units in the English dominion were (re-)defined in simple terms of English units, such as the Indian [[Tola (measure)|tola]] of 180 grains.
;Tod 
: This was an English weight for wool.<ref name=":0">{{Cite book|title = Encyclopaedia of Scientific Units, Weights and Measures|url = https://archive.org/details/encyclopaediaofs0000card|url-access = registration|last = Cardarelli|first = François |publisher = Springer|year = 2003|isbn = 978-1-4471-1122-1|location = London|pages = [https://archive.org/details/encyclopaediaofs0000card/page/49 49]}}</ref> It has the alternative spelling forms of ''tode'', ''todd'', ''todde'', ''toad'', and ''tood''.<ref name=Zupko1985>{{cite book|last1=Zupko|first1=Ronald Edward|title=A Dictionary of Weights and Measures for the British Isles: The Middle Ages to the Twentieth Century, Volume 168|date=1985|publisher=American Philosophical Society|isbn=978-0-87169-168-2|pages=415–416|url=https://books.google.com/books?id=0l_k-XMIiQIC&q=todde+wool&pg=PA415|access-date=3 March 2015}}</ref> It was usually 28 pounds, or two [[stone (unit)|stone]].<ref name="Zupko1985" /> The tod, however, was not a national standard and could vary by English [[shire]], ranging from 28 to 32 pounds.<ref name="Zupko1985" />  In addition to the traditional definition in terms of pounds, the tod has historically also been considered to be {{frac|1|13}} of a [[sack (unit)|sack]], {{frac|1|26}} of a [[sarpler]],<ref name="Zupko1985" /> or {{frac|1|9}} of a wey.<ref name=":0" />

{{English pounds}}

== See also ==
{{colbegin}}
* {{Annotated link |Approximate conversion of units}}
* {{Annotated link |Ancient Roman units of measurement|Ancient Roman Units of Measurement}}
* {{Annotated link |Comparison of the imperial and US customary measurement systems}}
* {{Annotated link |Domesday Book}}
* {{Annotated link |English Engineering Units}}
* {{Annotated link |Feudalism}}
* {{Annotated link |History of measurement}}
* {{annotated link|Hundred (unit)|Hundred}}, a unit of 100 or 120 items
* {{Annotated link |Imperial and US customary measurement systems}}
* {{Annotated link |Imperial units}}
* {{Annotated link |Long hundred}}
* {{Annotated link |Metrication}}
* {{Annotated link |Obsolete Scottish units of measurement}}
* {{Annotated link |Plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States}}
* {{Annotated link |Slug (unit)|Slug}}
** {{Annotated link |poundal}}
* {{Annotated link |Spanish customary units}}
* {{Annotated link |Weights and measures}}
* {{Annotated link |Welsh units}}
* {{Annotated link |Winchester measure}}
{{colend}}

==Notes==
{{notelist}}

== References ==
{{Reflist}}

== External links ==
* [http://www.unc.edu/~rowlett/units/custom.html English Customary Weights and Measures] {{Webarchive|url=https://web.archive.org/web/20080724202847/http://www.unc.edu/~rowlett/units/custom.html |date=2008-07-24 }}
* Jacques J. Proot's [https://web.archive.org/web/20051030024814/http://users.aol.com/jackproot/met/spvolas.html Anglo-Saxon weights & measures] page. [https://web.archive.org/web/*sa_/http://users.aol.com/JackProot/met/spvolas.html Internet Archive Wayback Machine]
* Alexander Justice, "[http://pierre-marteau.com/wiki/index.php?title=London:Measures A General Discourse of the Weights and Measures]" (London, 1707).

{{systems of measurement}}
{{Imperial units}}

[[Category:Imperial units]]
[[Category:Customary units of measurement]]
[[Category:Economic history of England]]
[[Category:Units of measurement by country]]