Perch (unit of measure)
Encyclopedia
A perch is as a unit of measurement used for length, area, and volume in a number of systems of measurement. Its name derives from the Ancient Roman unit
, the pertica.
perche, derived from the Latin
pertica, meaning a pole or staff. Originating in Roman antiquity, it spread with the Roman Empire
and was likely re-introduced to England
with the Norman Conquest
of 1066. In the Roman Empire, France and England, it also could mean area (square perches), and among operative masons of the Middle Ages, volume.
varied from 10 feet (perche romanie) to 22 feet (perche d'arpent - apparently 1/10 of "the range of an arrow". - about 220 feet). To confuse matters further, by ancient Roman definition, an arpent equalled 120 Roman feet.
In England, the perch was officially discouraged in favour of the rod
as early as the 15th century, however local customs maintained its use. In the 13th Century Perches were variously recorded in lengths of 18 feet (5.49 m), 20 feet (6.1 m), 22 feet (6.71 m) and 24 feet (7.32 m); and even as late as 1820, a House of Commons report notes lengths of 16.5 feet (5.03 m), 18 feet (5.49 m), 21 feet (6.4 m), 24 feet (7.32 m), and even 25 feet (7.62 m). In Ireland
, a perch was standardized at 21 feet (6.4 m), making an Irish chain, furlong
and mile proportionately longer by 27.27% than the "standard" English measure.
The rod as a survey
measure was standardized by Edmund Gunter
in England in 1607 as one-fourth of a chain
(of 66 feet (20.12 m)), or 16+1/2 ft long.
, a square perch (the perch being standardized to equal 16.5 feet) is equal to a square rod, 30+1/4 sqyd or 0.00625 acre
s. There are 40 square perches to a rood
, 160 square perches to an acre
. This unit was usually referred to as a perch or pole even though square perch and square pole were the more precise terms. Confusingly, rod was used as a unit of area but it meant a rood.
The Perch remains a standard unit of land area used in Sri Lanka being equivalent to 25 square metres.
Obviously, regional interpretations of perch would yield different results.
Ancient Roman units of measurement
The ancient Roman units of measurement were built on the Hellenic system with Egyptian, Hebrew, and Mesopotamian influences. The Roman units were comparatively consistent and well documented.-Length:Notes...
, the pertica.
Origin
The word perch is from the FrenchFrench language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...
perche, derived from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
pertica, meaning a pole or staff. Originating in Roman antiquity, it spread with the Roman Empire
Roman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....
and was likely re-introduced to England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
with the Norman Conquest
Norman conquest of England
The Norman conquest of England began on 28 September 1066 with the invasion of England by William, Duke of Normandy. William became known as William the Conqueror after his victory at the Battle of Hastings on 14 October 1066, defeating King Harold II of England...
of 1066. In the Roman Empire, France and England, it also could mean area (square perches), and among operative masons of the Middle Ages, volume.
Length
The perch as a lineal measure in Rome, was 10 feet (3.05 m), and in FranceFrance
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
varied from 10 feet (perche romanie) to 22 feet (perche d'arpent - apparently 1/10 of "the range of an arrow". - about 220 feet). To confuse matters further, by ancient Roman definition, an arpent equalled 120 Roman feet.
In England, the perch was officially discouraged in favour of the rod
Rod (unit)
The rod is a unit of length equal to 5.5 yards, 5.0292 metres, 16.5 feet, or of a statute mile. A rod is the same length as a perch or a pole. In old English, the term lug is also used.-History:...
as early as the 15th century, however local customs maintained its use. In the 13th Century Perches were variously recorded in lengths of 18 feet (5.49 m), 20 feet (6.1 m), 22 feet (6.71 m) and 24 feet (7.32 m); and even as late as 1820, a House of Commons report notes lengths of 16.5 feet (5.03 m), 18 feet (5.49 m), 21 feet (6.4 m), 24 feet (7.32 m), and even 25 feet (7.62 m). In Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
, a perch was standardized at 21 feet (6.4 m), making an Irish chain, furlong
Furlong
A furlong is a measure of distance in imperial units and U.S. customary units equal to one-eighth of a mile, equivalent to 220 yards, 660 feet, 40 rods, or 10 chains. The exact value of the furlong varies slightly among English-speaking countries....
and mile proportionately longer by 27.27% than the "standard" English measure.
The rod as a survey
Surveying
See Also: Public Land Survey SystemSurveying or land surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them...
measure was standardized by Edmund Gunter
Edmund Gunter
Edmund Gunter , English mathematician, of Welsh descent, was born in Hertfordshire in 1581.He was educated at Westminster School, and in 1599 was elected a student of Christ Church, Oxford. He took orders, became a preacher in 1614, and in 1615 proceeded to the degree of bachelor in divinity...
in England in 1607 as one-fourth of a chain
Chain (unit)
A chain is a unit of length; it measures 66 feet or 22 yards or 100 links . There are 10 chains in a furlong, and 80 chains in one statute mile. An acre is the area of 10 square chains...
(of 66 feet (20.12 m)), or 16+1/2 ft long.
Area
As a unit of areaArea
Area is a quantity that expresses the extent of a two-dimensional surface or shape in the plane. Area can be understood as the amount of material with a given thickness that would be necessary to fashion a model of the shape, or the amount of paint necessary to cover the surface with a single coat...
, a square perch (the perch being standardized to equal 16.5 feet) is equal to a square rod, 30+1/4 sqyd or 0.00625 acre
Acre
The acre is a unit of area in a number of different systems, including the imperial and U.S. customary systems. The most commonly used acres today are the international acre and, in the United States, the survey acre. The most common use of the acre is to measure tracts of land.The acre is related...
s. There are 40 square perches to a rood
Rood (measurement)
Rood has several distinct meanings, all derived from the same basic etymology. The most significant are an obsolete English measure of area, an obsolete English measure of length, and a term for a cross or crucifix, especially a large one displayed in a church....
, 160 square perches to an acre
Acre
The acre is a unit of area in a number of different systems, including the imperial and U.S. customary systems. The most commonly used acres today are the international acre and, in the United States, the survey acre. The most common use of the acre is to measure tracts of land.The acre is related...
. This unit was usually referred to as a perch or pole even though square perch and square pole were the more precise terms. Confusingly, rod was used as a unit of area but it meant a rood.
The Perch remains a standard unit of land area used in Sri Lanka being equivalent to 25 square metres.
Obviously, regional interpretations of perch would yield different results.