Geometry (Ancient Greek: geo- “earth“, -metron “measurement“) was originally dealing with measuring of the earth. In our article “How ancient astronomers could have establish dimensions of the Earth?” we presented a simple method of establishing circumference (and diameter) of the earth that (most likely) was used by the ancient astronomers.
Measurement means the act of measuring or the size of something
To Measure means to ascertain the dimensions, capacity, or amount (quantity) of something.A unit of measurement is a definite magnitude of a physical quantity, defined and adopted by convention and/or by law, that isused as a standard for measurement of the same physical quantity. Any other value of the physical quantity can be expressed as a simple multiple of the unit of measurement.People have always found it necessary to measure time, distance, area, volume and weight, and have devised units that measure these quantities. For time, there is an absolute standard in the motions of the heavens, but for the other quantities the units have had to be chosen arbitrarily.Official view is that only recently have we succeeded in creating system of measurement accepted all over the world as the standard system for use in science and trade: The International System of Units (SI). However some researchers suggest that in ancient times people were commonly using units of measure related to dimensions of our planet and similar in value ( closely related to each other.)
It is important to notice that units of measure we use today are connected with the size and movements of our planet.
The same applies to the ancient units of measure.
Units of Length
Meter
Originally, the meter was designed to be one ten-millionth (1/10,000,000) of a quadrant, the distance between the Equator and the North Pole. In other words, meter was defined as 1/10,000,000 of the distance from the Earth’s equator to the North Pole measured on the circumference through Paris. Using this unit, the circumference of perfectly round Earth should be exactly 40,000, 000 meters (or 40,000 km).
Today, official value of the Earth’s circumference along the line of longitude is 40,007.86 km.
Nautical Mile
A nautical mile ( 1.852 km ) is based on the circumference of Earth. If you divide circumference of the Earth into 360 degrees and then divide each degree into 60 minutes you will get 21,600 minutes of arc.
1 nautical mile is defined as 1 minute of arc (of the circumference of Earth) is This unit of measurement is used by all nations for air and sea travel. Using 40,007.86 km as the official circumference of our planet we get value of the nautical mile in kilometers: 1.852 km (40,007.86/21,600 )
The metric system
The metric system, originating in the French Revolution and propagated widely in the 19th century, has brought a dreary but convenient uniformity to units of measurement. A number of metric systems of units have evolved since the adoption of the original metric system in France in 1791. The current international standard metric system is the International System of Units (SI). An important feature of modern systems is standardization. Each unit has a universally recognized size. In the establishment of the metric system, the quadrant of the earth was measured and set equal to 10,000,000 meters.
The guiding ideas of the French scientists are well expressed in the introduction to the document presented to the Academy:
The idea to refer all measures to a unit of length taken from nature has appeared to the mathematicians since they learned the existence of such a unit as well as the possibility to establish it: they realized it was the only way to exclude any arbitrariness from the system of measures and to be sure to preserve it unchanged for ever, without any event, except a revolution in the world order, could cast some doubts in it; they felt that such a system did not belong to a single nation and no country could flatter itself by seeing it adopted by all the others.
Actually, if a unit of measure which has already been in use in a country were adopted, it would be difficult to explain to the others the reasons for this preference that were able to balance that spirit of repugnance, if not philosophical at least very natural, that peoples always feel towards an imitation looking like the admission of a sort of inferiority. As a consequence, there would be as many measures as nations.
The International System of Units (abbreviated SI from French), established in 1960, is the modern form of the metric system and is generally a system of units of measurement devised around seven base units and the convenience of the number ten.
The SI, is the world’s most widely used system of measurement, which is used both in everyday commerce and in science. The system has been nearly globally adopted with the United States being the only industrialized nation that does not mainly use the metric system in its commercial and standards activities. The United Kingdom has officially partially adopted metrication, with no intention of replacing customary measures entirely. Canada has adopted it for all legal purposes but imperial/US units are still in use, particularly in the buildings trade.
meter or metre (m) – the metric and SI base unit of distance.
Originally, the meter was designed to be one ten-millionth (1/10,000,000) of a quadrant, the distance between the Equator and the North Pole. In other words, meter was defined as 1/10,000,000 of the distance from the Earth’s equator to the North Pole measured on the circumference through Paris. (The Earth is difficult to measure, and a small error was made in correcting for the flattening caused by the Earth’s rotation. As a result, the meter is too short by a bit less than 0.02%. That’s not bad for a measurement made in the 1790’s.)
For practical reasons, for a long time, the meter was precisely defined as the length of an actual object, a bar kept at the International Bureau of Weights and Measures in Paris.
In recent years, however, the SI base units (with one exception) have been redefined in abstract terms so they can be reproduced to any desired level of accuracy in a well-equipped laboratory.
The 17th General Conference on Weights and Measures in 1983 defined the meter as that“distance that makes the speed of light in a vacuum equal to exactly 299, 792, 458 meters per second”. In other words, ”The metre is the length of the path traveled by light in vacuum during a time interval of 1/299, 792, 458 of a second.” The speed of light in a vacuum, c, is one of the fundamental constants of nature. Since c defines the meter now, experiments made to measure the speed of light are now interpreted as measurements of the meter instead.
The meter is equal to approximately:
1.093 613 3 yards,
3.280 840 feet, or
39.370 079 inches.
Its name comes from the Latin metrum and the Greek metron, both meaning “measure.” The unit is spelled meter in the U.S. and metre in Britain; there are many other spellings in various languages
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