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Published byMarian Carson Modified over 8 years ago
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Web search By: Spenser Martin
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First recorded measurements The first civilizations to record measurements were the ancient peoples of Egypt, Mesopotamia and the Indus Valley, and perhaps also Elam (in Iran) as well, around the 3 rd or 4 th millennia. Early Babylonian and Egyptian records and the Bible indicate that length was first measured with the forearm, hand, or finger and that time was measured by the periods of the sun, moon, and other heavenly bodies.
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First recorded measurements The Egyptian cubit, or the common cubit was the length of the forearm from the elbow to the tip of the middle finger. It was divided into the span of the hand (one-half cubit), the palm or width of the hand (one sixth), and the digit or width of the middle finger (one twenty-fourth) and the span or the length between the tip little finger to the tip of the thumb.
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The Roman foot It was the Greeks who developed the "foot" as their fundamental unit of length. Legend has it that this Greek unit was based on an actual measurement of Hercules' foot, the Romans who adopted Greek culture adopted its measurements too. The Romans measured their pace steps, of about 2.5 feet, 1000 double paces formed a mile.
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The Roman Yard Romans measured a yard of cloth by the distance between the end of the outstretched arm and their chin.
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France and its metrics The National Assembly of France told scientists "deduce an invariable standard for all the measures and all the weights." They said this because the old system of measurement was confusing because not everybody body was the same. The Commission appointed by the Academy created a system that was, at once, simple and scientific. The unit of length was to be a portion of the Earth's circumference.
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France and its metrics The Commission assigned the name metre – meter - to the unit of length. This name was derived from the Greek word metron, meaning "a measure." The physical standard representing the meter was to be constructed so that it would equal one ten-millionth of the distance from the North Pole to the equator along the meridian running near Dunkirk in France and Barcelona in Spain.
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Treaty of the meter The Treaty of the Meter (also known as the Metre Convention) is a treaty which created three organizations tasked with supervising the keeping of metric standards: (1) International Bureau of Weights and Measures (BIPM); (2) General Conference on Weights and Measures (CGPM); (3) International Committee for Weights and Measures (CIPM). (The initializes are derived from the French names for the organizations as the treaty was written in French.)
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Treaty of the meter The BIPM is under the authority of the CGPM, and under the supervision of the CIPM. The treaty was signed in 1875 and slightly revised in 1921. The system of units established by the treaty was later renamed the International System of Units (SI) in 1960. There were 17 original signatories of the treaty, but this number grew to 52 by the start of 2009.
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The meter in 1791 The French Academy of Sciences decided in 1791 that the meter would be defined by the dimensions of the planet earth. The meter would be a unit of length such that Earth's meridian line (a line linking the equator with the north pole) was equal to ten million meters. Over the following years measurements of the meridian line that passes through Paris were attempted, so that a standard meter could be cast in metal.
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Redefined meter in 1983 On October 20, 1983, the meter was officially redefined as the distance traveled by light in a vacuum during a time interval of 1/299,792,458 of a second. The original definitions (1799 and 1899) depended on a measured standard bar. In 1960, it was redefined as a relationship to the wavelength of light from ions of the element krypton. In 1980, the standard was based on the unusually cohesive wavelength of an iodine-stabilized helium-neon laser.
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The metric act The Metric Act of 1866, also known as the Kasson Act, is a piece of United States legislation that authorized the use of the metric system The metric system is already used in some arts and trades in this country, and is especially adapted to the wants of others. Some of its measures are already manufactured at Bangor, in Maine, to meet an existing demand at home and abroad. The manufacturers of the well-known Fairbanks scales state: “For many years we have had a large export demand for our scales with French weights, and the demand and sale is constantly increasing.”
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The metric act The Act was originally introduced as H.R. 596 in the 39th Congress. The House passed it on 17 May 1866; the Senate passed it on July 27, 1866; and it was presented to the President and signed the next day. The Act included a now-obsolete definition of the metric system and tables of units. On August 9, 2007, the Act was amended by Pub.L. 110-69, the America COMPETES Act. It replaced the old definition of the metric system with the modern-day definition of SI.
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Early tools Some early tools included…….. Parts of body including arm, leg, and neck Protractor: An instrument used to construct and measure plane angles. The simple protractor looks like a semicircular disk marked with degrees, from 0º to 180º Sextant: In 1731, Thomas Godfrey and John Hadley independently invented the reflecting quadrant, a precursor to the sextant. These were not the only ones but they were most widely used.
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Engineering blunders A blunder is a gross stupid or careless mistake, therefore we know that an engineering blunder is a mistake in the making or designing of a project. The most famous one is the Great Kersten Blunder(Kersten was the programmer that made the error). The Vigor space probe was sent towards Venus, but because of the computer programming error installed on it, This error caused it to miss Venus completely and was sent hurling into space. Over 2 billion dollars of technology was lost because of one simple error.
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Engineering blunders Fort Montgomery (Lake Champlain) was sometimes referred to as "Fort Blunder", because the first version of the U.S. fort was inadvertently built on the Canadian side of the border.
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