English units


English units are the units of measurement used in England up to 1826, which evolved as a combination of the Anglo-Saxon and Roman systems of units. Various standards have applied to English units at different times, in different places, and for different applications.
The two main sets of English units were the Winchester Units, used from 1495–1587, as affirmed by King Henry VII, and the Exchequer Standards, in use from 1588–1825, as defined by Queen Elizabeth I.
The English units were replaced by Imperial Units in 1824 by a Weights and Measures Act, which retained many though not all of the unit names and redefined many of the definitions.
Use of the term "English units" can be ambiguous, as, in addition to the meaning used in this article, it is sometimes mistakenly used to refer to United States customary units, which have somewhat different definitions, or to Imperial units, the standard units throughout the British Empire and Commonwealth.

History

Very little is known of the measurement units of 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 period, the North German foot of 13.2 inches 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 × 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 continued, in contrast to other Germanic countries which adopted the name "mile" for a longer native length closer to the league. From the time of Offa King of Mercia until 1526 the Saxon pound, also known as the moneyers' pound was the fundamental unit of weight.
Prior to the enactment of a law known as the "Composition of Yards and Perches" 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 retained the Anglo-Saxon rod of 5.03 metres and the acre of 4 × 40 rods. However, it redefined the yard, foot, inch, and barleycorn to of their previous value. Thus, the rod went from 5 old yards to new yards, or 15 old feet to new feet. The furlong went from 600 old feet to 660 new feet. 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.
Contrary to popular belief, the Norman conquest of England had little effect on British weights and measures, other than to introduce one new unit: the bushel. 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. Another popular myth is that the Magna Carta of 1215 had a significant effect on English weights and measures, for this document only mentions one unit but does not define it.
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. 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 in 1959. 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
; Poppyseed : or of a barleycorn
; Line : of a barleycorn
; Barleycorn : of an inch, the notional base unit under the Composition of Yards and Perches.
; Digit : inch
; Finger : inch
; Inch : 3 barleycorns
; Nail : 3 digits = inches = yard
; Palm : 3 inches
; Hand : 4 inches
; Shaftment : Width of the hand and outstretched thumb, inches before 1066, 6 thereafter
; Link : 7.92 inches or one 100th of a chain.
; Span : Width of the outstretched hand, from the tip of the thumb to the tip of the little finger, 3 palms = 9 inches.
; Foot : Prior to the Anglo-Saxon invasions, the Roman foot of was used. The Anglo-Saxons introduced a North-German foot of, divided into 4 palms or 12 thumbs, while the Roman foot continued to be used in the construction crafts. In the late 13th century, the modern foot of 304.8 mm was introduced, equal to exactly Anglo-Saxon foot.
; Cubit : From fingertips to elbow, 18 inches.
; Yard : 3 feet = 36 inches, the practical base unit as the length of the prototype bar held by the Crown or Exchequer.
; Ell : From fingertip of outstretched arm to opposite shoulder, 20 nails = yard or 45 inches. Mostly for measuring cloth.
; Fathom : Distance between arms outstretched, from fingertip to fingertip, equalling 6 feet.
; Rod : Used for surveying land and in architecture. The rod is the same length today as in Anglo-Saxon times, although its composition in terms of feet were changed by the Composition of Yards and Perches from 15 feet to. The pole is commonly used as a measurement for Allotment Gardens.
; Chain : 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 66 feet.
; Furlong : 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 and 40 rods or 660 feet afterwards.
; Mile : Originally the Roman mile alternatively reckoned as 5000 feet, 1000 paces, or 8 stades 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 : Notionally an hour's travel, but usually reckoned as three miles. Approximate length of the traditional "mile" in German and Scandinavian countries.

Area

; Perch: an area equal to one square rod.
; Rood: one quarter of an acre, confusingly sometimes called an acre itself in many ancient contexts. One furlong in length by one rod in width, or 40 square rods.
; Acre: area of land one chain in width 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 4,840 square yards, in Scotland 6,150 square yards and in Ireland 7,840 square yards. It is a Saxon unit, meaning field. Traditionally said to be "as much area as could be ploughed in one day".
; Bovate: the amount of land one ox can plough in a single year. Approximately 15 acres or one eighth of a carucate.
; Virgate: the amount of land a pair of oxen can plough in a single year. Approximately 30 acres.
; Carucate: an area equal to that which can be ploughed by one eight-oxen team in a single year. Approximately 120 acres.

Administrative units

; 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 or wapentake: 100 hides grouped for administrative purposes.

Volume

Many measures of 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, and an ale gallon of 282 cubic inches, were commonly used for many decades prior to the establishment of the 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 such as the fluid ounce 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

;Dram: 60 minim or drops or fluid ounce
;Teaspoon: 80 minim or drops or fl oz
;Tablespoon: 4 dram, 3 teaspoons, or fl oz
;Jack: usually gill, in some dialects equal to a gill or pint
;Gill or Jill: 2 jacks, pint, or gallon, in some dialects pint
;Pint: 2 cups or gallon
;Quart: 2 pints or gallon
;Pottle: 2 quarts or gallon
;Gallon: 2 pottle, 4 quarts, 8 pints
Liquid measures as binary submultiples of their respective gallons :
jackgillpintquartpottlegallon2n gal.
1 jack =1–6
1 gill =21–5
1 pint =841–3
1 quart =16821–2
1 pottle =3216421–1
1 gallon =643284210

Wine

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.
The wine gallon was re-established by 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. Defined as 231 cubic inches, it differs from the later imperial gallon, but is equal to the United States customary gallon.
;Rundlet: 18 wine gallons or wine pipe
;Wine barrel: 31.5 wine gallons or wine hogshead
;Tierce: 42 wine gallons, puncheon or wine pipe
;Wine hogshead: 2 wine barrels, 63 wine gallons or wine tun
;Puncheon or tertian: 2 tierce, 84 wine gallons or wine tun
;Wine pipe or butt: 2 wine hogshead, 3 tierce, 7 roundlet or 126 wine gallons
;Wine tun: 2 wine pipe, 3 puncheon or 252 wine gallons

Ale and beer

;Pin: 4.5 gallons or beer barrel
;Firkin: 2 pins, 9 gallons or beer barrel
;Kilderkin: 2 firkins, 18 gallons or beer barrel
;Beer barrel: 2 kilderkins, 36 gallons or beer hogshead
;Beer hogshead: 3 kilderkins, 54 gallons or 1.5 beer barrels
;Beer pipe or butt: 2 beer hogsheads, 3 beer barrels or 108 gallons
;Beer tun: 2 beer pipes or 216 gallons

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.
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 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.
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 multiples of the bushel:
pintquartpottlegallonpeckkenningbushelstrikecoombseam2n gal.
1 pint =1–3
1 quart =21–2
1 pottle =421–1
1 gallon =84210
1 peck =1684211
1 kenning =321684212
1 bushel =64321684213
1 strike =12864321684214
1 coomb =25612864321684215
1 seam =51225612864321684216

Other units included the wey, and the last.

Specific goods

;Perch: 24.75 cubic feet of dry stone, derived from the more commonly known perch, a unit of length equal to 16.5 feet.
;Cord: 128 cubic feet of firewood, a stack of firewood 4 ft × 4 ft × 8 ft

Weight

The Avoirdupois, Troy and Apothecary systems of weights all shared the same finest unit, the grain; however, they differ as to the number of grains there are in a dram, ounce and 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 grains or about 48.6 milligrams.
The avoirdupois pound contained 7,000 grains and was used for all products not subject to Apothecaries's or Tower weight.

Avoirdupois

; Grain : 64.79891 mg, of a pound
; Dram/drachm : 27.34375 gr
; Ounce : 16 dr = 437.5 grains ≈ 28 g
; Pound : 16 oz = 7000 grains ≈ 454 g
; Quarter : cwt
; Hundredweight : 112 lb
; Ton : 20 cwt
Additions:
; Nail : cwt = 7 lb
; Clove : 7 lb or 8 lb
; Stone : 14 lb
; Tod : 2 st = 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. No standards of the Tower pound are known to have survived.
In terms of nominal currency units, a pound was 20 shillings of 12 pennies each from the late 8th century to 1971 in the United Kingdom.

Troy

; Grain : = 64.79891 mg
; Pennyweight : 24 gr ≈ 1.56 g
; Ounce : 20 dwt = 480 gr ≈ 31.1 g
; Pound : 12 oz t = 5760 gr ≈ 373 g
; Mark: 8 oz t

Tower

; Grain : = gr t ≈ 45.6 mg
; Pennyweight : 32 gr T = gr t ≈ 1.46 g
; Tower ounce : 20 dwt T = 640 gr T = 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: 8 oz T ≈ 233 g

Apothecary

; Grain : = 64.79891 mg
; Scruple : 20 gr
; Dram : 3 s ap = 60 gr
; Ounce : 8 dr ap = 480 gr
; Pound : 5760 gr = 1 lb t

Others

; Merchants/Mercantile pound : 15 oz tower = 6750 gr ≈ 437.4 g
; London/Mercantile pound : 15 oz troy = 16 oz tower = 7200 gr ≈ 466.6 g
; Mercantile stone : 12 lb L ≈ 5.6 kg
; Butcher's stone : 8 lb ≈ 3.63 kg
; Sack : 26 st = 364 lb ≈ 165 kg
;Tod