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Sunday 5 May 2019

Weights and measures

The earliest known uniform systems of measurement seem to have all been created sometime in the 4th and 3rd millennia BC among the ancient peoples of Egypt, Mesopotamia and the Indus Valley.

One method of calculation in Biblical times was the area which a yoke of oxen could plough in a day (Isaiah 5 v10).

In ancient Rome land distances were measured in paces, one pace being defined as two steps, or approximately 5 feet (152 cms).

Ancients hired "bematists" to measure the long distances, They were trained to count steps while walking between locations and could measure hundreds of miles with 95% plus accuracy. Eratosthenes used one to calculate the circumference of the Earth within 15% in 240 BC.

The word mile comes from the largest unit of land measure used by the Romans, the "milia passuum" meaning 1,000 paces. The Roman army, marching through uncharted territory, used to place a stick in the ground every 1,000 paces (where each pace was two steps).

Units of measurement, Palazzo della Ragione, Padua By Fabrizio Pivari

A 'butt' was a medieval unit of measure for wine. Technically, a buttload of wine is about 475 liters, or 126 gallons.

English miles varied until 1593 when an Act of Parliament laid down that: "A mile shall contain eight furlongs, every furlong 40 poles and every pole shall contain 16 foot and an half".

James Watt needed to convince sceptics to ditch their draft horses and buy his steam engine. To prove its superiority, he measured a horse walking in ­circles to turn a grindstone in a mill. He multiplied distance it walked by its 180 pounds of pulling force and came up with a new measure: horsepower.

In pre-revolutionary France, there were up to 250,000 different units of weights and measures, with variations across almost every province, district and town. The French Academy of Sciences in 1791 advised adopting the metre as the name for a universal unit of length.

English mathematician-physicist Christopher Wren had earlier recommended, as a standard unit, the length of a pendulum producing a half period of one second. A metre was defined by The French Academy of Sciences  as one ten-millionth of the distance from the North Pole to the Equator via Paris. That worked out at about 3mm longer than Wren's suggested pendulum. The French then constructed a metal bar the length of which would serve as a standard metre. Actually the job was too precise for French engineers and the work was carried out in London.

An example of metrication in 1860 when Tuscany became part of modern Italy. By Assianir

On December 10, 1799 France became the first country to adopt the metric system as its system for weights and measures. The law that established the metric system was called the Loi du 19 frimaire An VIII, which was passed by the French National Assembly. The law defined the metre as one ten-millionth of the distance from the North Pole to the Equator passing through Paris. The metre was also defined as equal to the length of a platinum bar that was preserved in the National Archives in Paris. The metric system was designed to be a universal system of measurement that would be easy to use and understand. It is now used in most countries around the world.

The US may have adopted the metric system in the early 19th century if pirates hadn’t kidnapped the French scientist sent to help Thomas Jefferson persuade Congress to adopt the system. The scientist,  Joseph Dombey, was taken prisoner on the island of Montserrat, where they hoped to obtain a ransom for him. Unfortunately for the pirates, and for Dombey as well, he died in captivity.

If Thomas Jefferson's decimal-based system had been adopted, 1 mile would equal 10,000 ft, an inch would be divisible by 10, and 1 cubic foot would equal exactly 1,000 ounces.

The metric system was legalized by the U.S. Congress for the standardization of weights and measures throughout the United States in 1866. The legislation legally protected use of the metric system in commerce from lawsuit, and provided an official conversion table from U.S. customary units.

On May 20, 1889, representatives from seventeen countries signed the Metre Convention. The treaty created the International Bureau of Weights and Measures (BIPM), an intergovernmental organization under the authority of the General Conference on Weights and Measures (CGPM) and the supervision of the International Committee for Weights and Measures (CIPM), that coordinates international metrology and the development of the metric system.

The first General Conference on Weights and Measures in 1889 defined the length of a meter as the distance between two lines on a standard bar of an alloy of platinum with ten percent iridium, measured at the melting point of ice.

In 1960, a more precise definition was of a metre adopted based on radiation wavelengths in a krypton atom.

The former Weights and Measures office in Seven Sisters, London. By Nico Hogg 

In 1959, specific values for the international yard, avoirdupois pound and derived units (e.g. inch, mile and ounce) were adopted after agreement between the U.S.A., the United Kingdom and other Commonwealth countries. It was agreed that an inch, once defined as the length of three corns of barley, was 25.4mm.

At the seventeenth General Conference on Weights and Measures on October 21, 1983, the length of a metre was redefined as the distance light travels in vacuum in 1/299,792,458 of a second.  This redefinition of the meter was a significant advancement in metrology, as it made the meter a fundamental unit of length based on a natural constant, the speed of light. This definition is also more precise and reproducible than previous definitions, which were based on physical artifacts such as meter bars.

On November 16, 2018, the 26th General Conference on Weights and Measures (CGPM) voted unanimously in favor of revised definitions of the units kilogram, ampere, kelvin and mole. The new definitions came into force on May 20, 2019.

The reason why an Air Canada flight ran out of fuel mid flight in 1983, NASA lost its Mars orbiter in 1999, and a roller coaster car derailed on Space Mountain in 2003 were due to confusion in working with both imperial and metric systems.

"Le Grand K" is a hunk of platinum kept in a vault in a Paris, that was the international prototype for a kilogram of weight. This changed in 2018, and a kilogram's weight is now defined based on the laws of the universe so as to avoid a physical object that decays over time.

FUN WEIGHT AND MEASURES FACTS

An acre was historically the amount of land tillable by one man behind one ox in one day. Poor farming technologies and the need for farmland to be close to the river means that acres were traditionally long and narrow.

The unit of measurement "smoot" is named after an MIT prank on Lambda Chi Alpha fraternity pledge, Oliver Smoot, whose body was used to measure the Harvard Bridge in 1958. One smoot is 5 foot 7 inches and length of the Harvard Bridge is 364.4 smoots.

Earth's circumference around the poles is almost exactly 40,000 kilometres or 21,600 (i.e. 360 × 60) nautical miles, because it was used to define those units of measurement.

The longest unit of length is the yottametre, which is 1,000,000,000,000,000,000,000,000 metres.


In Tibet distances used to be measured by the number of cups of tea that would need to be drunk to get there.

The Sami people of northern Finland use a measure called Poronkusema: the distance a reindeer can walk before needing to urinate.

Myanmar (Burma) doesn't use the metric system, but it doesn't use the imperial system either, instead, they have their own system of measurement called the Burmese system.

We use "lbs" as shorthand for pounds in English because of the Latin phrase "libra poundo" meaning “a pound by weight”. The libra part of the phrase meant both weight or balance scales. The Latin usage was shortened to libra, which naturally was abbreviated "lb". We adopted the pound part from pondo, yet kept the abbreviation for libra.

The average adult weight worldwide is 62.0kg (136.7lb). The US average is 80.7kg (177.9lb). In the UK, the average figures are 83.6kg (13.16 stone) for men, 70.2kg (11 stone) for women.

Historically vague measurements "dash, pinch, smidgen" are mostly real cooking measurements that have generally agreed-upon amounts. A dash is ​1⁄8 teaspoon, a pinch ​1⁄16 teaspoon, and a smidgen is ​1⁄32 teaspoon.

Source Daily Express

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