Yard

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Pattern located in the Greenwich observatory.

The yard (from English: yard) (symbol: yd) is the basic unit of length in systems of measurement used in United States, Panama[citation required] and the United Kingdom. In almost all countries the meter is officially used as the measure of length, and in the countries mentioned it is in a transition stage.

Equivalences:

1 yd = 0.9144 m
1 m = 1,093 yd

History

Origin

The origin of the yard measure is uncertain. Both the Romans and the Welsh used multiples of a shorter foot, but 2 1⁄2 Roman feet were a "step" (Latin, gradus) and 3 Welsh feet were a "step" (in Welsh, cam). Proto-Germanic cubit or arm length has been reconstructed as *alinâ, which developed into Old English ęln, Middle English elne, and modern ell 1.25 yards (1.1 m). This has led some to derive the English three-foot yard from the pace; to others of the ell or of the cubit; and others from the arm standard of Henry I. Based on the etymology of the other 'yard', some suggest that it originally derived from the circumference of a person's waist, while others believe that it originated as a cubic measure. An official British report writes:

The pattern of measurement has always been taken either from some part of the human body, like a foot, the length of the arm, the size of the hand, or from other natural objects, such as a barley grain, or other grain. But the yard was the original standard adopted by the first English sovereigns, and was supposed to be based on the chest width of the Saxon race. The yard remained until the reign of Henry VII, when the pot was introduced, which was a yard and a quarter, or 45 inches. The elongation was borrowed from the pañeros of Paris. Later, however, Queen Elizabeth reintroduced the yard as an English measurement pattern.

From ell to yard

The oldest record of a prototype measure is statute II Edgar Cap. 8 (AD 959 x 963), which survives in several variant manuscripts. In it, Edgar the Peaceful ordered the Witenagemot at Andover, Hampshire that "the measure held at Winchester" it was observed throughout his realm.(Thorpe, 1840) (In some manuscripts it reads "in London and in Winchester".)(Thorpe, 1840, p. 113)(Liebermann, 1903, p. 204- 206) William I's statutes likewise reference and maintain the standard measures of his predecessors without naming them.

William of Malmesbury's work Acts of the Kings of England records that during the reign of Henry I (1100 - 1135), "the measure of his arm was applied to correct the false ell of merchants and was imposed on everyone in all England"." The folktale that the length was limited by the king's nose (Green, 1986, p. 106) was added some centuries later. C.M. Watson dismisses William's account as 'childish', (Watson, 1910, pp. 36-39) but William was one of the most conscientious and reliable medieval historians. (Connor, 1987, p. xxiv) French "king foot" it was supposed to be derived from Charlemagne, (Connor, 1987, p. xxiv) and the English kings subsequently intervened repeatedly to impose shorter units in order to increase tax revenue.

The earliest surviving definition of this shorter unit appears in the Composition of Yards and Perches Act, one of the statutes of uncertain date tentatively dated to the reign of Edward I or II c. 1300. Its wording varies in the surviving accounts. One of them reads: Cotton MS Claudius D2, quoted and translated in Ruffhead.(Ruffhead, 1765, p. 421)

It is ordered that 3 dry and round barley grains make an inch, 12 inches make 1 foot, 3 feet make 1 yard, 5 yards and a half make a perch, and 40 long and 4 wide perches make a acre.

The Liber Horn compilation (1311) includes that statute with slightly different wording and adds: (Fowler, 1884, p. 276)

And remember that the iron yard of our Lord the King contains 3 feet and no more, and a foot must contain 12 inches for the correct measure of this measured yard, namely, the 36th part of this properly measured yard 1 inch or more or less and 5 yards and a half make a perch that is 16 feet and a half measured by the mentioned yard of our Lord the King.

In some of the earliest books, this law was attached to another statute of uncertain date entitled the Statute for the Survey of Lands. The law was not repealed until the Weights and Measures Act of 1824.

Yard and Inch

In a law of 1439 (18 Henry VI. Cap. 16.) the sale of cloth by the "yard and handful" and the "yard and inch" was instituted.

There will be only one measure of cloth in the whole kingdom for yard and inchand not for yard and handfulaccording to the London measure.

According to Connor, (Connor, 1987) cloth merchants had previously sold cloth by the yard and by the handful to evade high taxes on the cloth (the extra handful was essentially a black market transaction). Enforcement efforts caused cloth merchants to switch to the yard and inch, at which point the government gave in and made the yard and inch official. In 1552, the yard and the inch for the measurement of cloth were put back into law (5 and 6 Edward VI Ch. 6. A Law for the True Manufacture of Woolen Cloth)

XIV. And that each and every one of the broad fabrics and fabrics called Taunton, Bridgwaters fabrics, and other fabrics that are made after the aforementioned feast in Taunton, Bridgwater or other places of the same kind, should contain in the water between twelve and thirteen yards, yard and inch of the rule, and in the width seven quarters of yard: (2) And every narrow cloth manufactured after the aforementioned feast in the cities or any other place of the same class, must contain in the water a length of between three and twenty and five and twenty yards, yard and inch of the aforementioned rule, and in the width a yard of the same measure; (3) and all cloth of this type, both wide and narrow, that is well scarded, thickened, ground and completely dry, shall weigh xxxiv. li. the Piece at least. XV. And that all the fabrics known as Check-Kersie and Straits, which are made after the party, must contain, being wet, between seventeen and eighteen. yards, with the inches, as has been said before, and in width, a minimum yard in the water; and being well scarded, thickened, grounded and completely dry, will weigh xxiv. li. the piece at a minimum.

The yard and the inch for the measurement of the cloths were also sanctioned again in the legislation of 1557-1558 (4 and 5 Felipe and María Cap. 5. An act touching the making of woolen clothes. par. IX.)

IX. Item, that every ordinary kersie mentioned in that law must contain in the water between xvi. and xvii. yards, yard and inch; and being well degraded thick, ground, straightened and completely dry, shall weigh nineteen pounds the piece at a minimum:...

As recently as 1593, the same principle is found mentioned once more (35 Elizabeth. Ch. 10. An act for the reform of various abuses in clothing, called Devonshire kerjies [ sic] or dozens, according to a proclamation of the thirty-fourth year of the reign of our sovereign lady the Queen who is now. par. III.)

(2) and each and every one of the same kersies or dozens of Devonshire, being so gross, and as they come out of the weaver's loom (without transcending, stretching, forcing, or any other device to increase their length) will hold in length between fifteen and sixteen yards by the measure of yard and inch For the rule,

Physical standards

One of the oldest yards in existence is that of the Worshipful Company of Merchant Taylors. It consists of a hexagonal iron rod 5/8 inch (1.6 cm) in diameter and 1/100 inch (0 cm) short of a yard, encased within a silver rod stamped 1445.(Connor, 1987) In the early 15th century, the Merchant Taylors Company was licensed to "do the searching" at the opening of the annual St. Bartholomew's Day Cloth Fair. In the mid-18th century, Graham compared the Royal Society standard yardage with other existing standards. This was a standard "deprecated" made in 1490 during the reign of Henry VII, and a brass yard and brass ell from 1588 in the time of Queen Elizabeth and still in use at the time, kept in the Exchequer; a brass yard and a brass elbow in the Guildhall, London; and a brass yard presented to the Worshipful Company of Clockmakers by the Exchequer in 1671. The Exchequer yard was taken as "true"; the variation was found to be from +1⁄20 to -1⁄15 of an inch, and an additional graduation was made for the Exchequer's yardage in the Royal Society standard. In 1758 the legislature required the construction of a standard yard, which was made from the standard of the Royal Society and deposited with the clerk of the House of Commons; it was divided into feet, one of the feet into inches, and one of the inches into tenths. A copy of the same, but with vertical cheeks between which other yardsticks could be placed, was made for the Exchequer for its use. commercial.

19th century Britain

Following Royal Society research by John Playfair, Hyde Wollaston and John Warner in 1814, a committee of Parliament proposed to define the standard yardage based on the length of a seconds pendulum. This idea was examined but not approved. The Weights and Measures Act 1824 (5th George IV. Cap. 74.) An Act for ascertaining and establishing Uniformity of Weights and Measures stipulates that:

From and after First Day May The standard length of the two points shall be determined by the standard length of the two points.

In 1834, the main imperial yard standard was partially destroyed in a fire known as the Burning of Parliament. The following references are helpful in identifying the authors of the above reference: Ref., and Ref. }}. In 1838, a commission was formed to rebuild the lost standards, including the troy pound, which had also been destroyed. In 1845, a new yardage pattern was built based on two previously existing patterns known as A1 and A2, both made for the Ordnance Survey, and the R.S. 46, the yard of the Royal Astronomical Society. All three had been compared to the Imperial standard before the fire.

The new banner was made of Baily's metal #4, which consisted of 16 copper parts, 2 1⁄2 parts of tin and 1 part of zinc. It was 38 inches long and 1 inch square. The Weights and Measures Law of 1855 granted official recognition to the new standards. Between 1845 and 1855 forty yard patterns were built, one of which was selected as the new imperial pattern. Four others, known as Parliamentary Copies, were distributed to the Royal Mint, the Royal Society of London, the Royal Observatory in Greenwich, and the New Palace of Westminster, commonly called the Houses of Parliament. The other 35 yard patterns they were distributed to the cities of London, Edinburgh and Dublin, as well as to the United States and other countries (although only the first five were official). The imperial pattern received by the United States is known as "Bronze Yard No. 11"

The Weights and Measures Act of 1878 confirmed the status of the existing yard standard, mandated regular intercomparisons between the various yard standards, and authorized the construction of an additional Parliamentary Copy (made in 1879 and known as the Parliamentary Copy VI).

Definition of the yard in terms of the meter

Subsequent measurements revealed that the yardage pattern and its copies were shrinking at the rate of one part per million every twenty years due to the gradual release of stress suffered during the manufacturing process. The international prototype meter, by contrast, was comparatively stable. A measurement made in 1895 determined the length of the meter to be 39.370113 inches relative to the imperial standard yard. The Weights and Measures (Metrics) Act of 1897 together with Order in Council 411 (1898) made this relationship official. After 1898, the de facto legal definition of the yard became accepted as 36⁄39,370113 of one meter.

The yard (known as the 'international yard' in the United States) was legally defined as exactly 0.9144 meter in 1959 under a 1959 agreement between Australia, Canada, New Zealand, South Africa, the United Kingdom and the United States. In the United Kingdom, the provisions of the treaty were ratified by the Weights and Measures Act 1963. The 1855 Imperial Standard Yard was renamed the United Kingdom Primary Standard Yard and retained its official status as a national prototype yard.

Description

In line with other measurements based on the proportions of the human body defined by Vitruvius, one yard corresponds to half the length of the outstretched arms, which is equivalent to three feet. For this reason, it is conceptually equivalent to a Spanish vara (also equivalent to three Castilian feet). So, we must not confuse the Anglo-Saxon rod, whose translation into Spanish would be vara or caña, with the old Spanish measure called vara.

In the Anglo-Saxon system there are four yards, namely:

The International Yard and Pound Agreement of July 1959 defined the length of the international yard in the United States and Commonwealth countries as exactly 0.9144 meters. This was 2 ppm shorter than the previous US definition and 1.7 ppm longer than the previous British definition.

The 1959 agreement concluded a series of step-by-step events, triggered in particular by the British Standards Institution's adoption of a scientific standard inch of 25.4 millimeters in 1930.

Since the unit most used in the industrial and technical field is the inch (=1/36 yards), to avoid the inconveniences due to the discrepancy between the English and American yards it has been agreed that 1 inch = 25.4 mm at 20 °C, leaving the meter and the yard related by the equation shown at the beginning.

Equivalences