History of measurement
The earliest recorded systems of weights and measures originate in the 3rd or 4th millennium BC. Even the very earliest civilizations needed measurement for purposes of agriculture, construction and trade. Early standard units might only have applied to a single community or small region, with every area developing its own standards for lengths, areas, volumes and masses. Often such systems were closely tied to one field of use, so that volume measures used, for example, for dry grains were unrelated to those for liquids, with neither bearing any particular relationship to units of length used for measuring cloth or land. With development of manufacturing technologies, and the growing importance of trade between communities and ultimately across the Earth, standardized weights and measures became critical. Starting in the 18th century, modernized, simplified and uniform systems of weights and measures were developed, with the fundamental units defined by ever more precise methods in the science of metrology. The discovery and application of electricity was one factor motivating the development of standardized internationally applicable units.
Sources of information
The comparison of the dimensions of buildings with the descriptions of contemporary writers is another source of information. An interesting example of this is the comparison of the dimensions of the Greek Parthenon with the description given by Plutarch from which a fairly accurate idea of the size of the Attic foot is obtained. Because of the comparative volume of artifacts and documentation, much more is known today about the state-sanctioned measures of large, advanced societies than about those of smaller societies or about the informal measures that often coexisted with official ones. In some cases, there are only plausible theories and different interpretations can be matched to the evidences.
It is possible to group official measurement systems for large societies into historical systems that are relatively stable over time, including: the Babylonian system, the Egyptian system, the Phileterian system of the
Earliest known measurement systems
The earliest known uniform systems of weights and measures seem all to have been created at some time in the
) as well.Early
History of units
Units of length
The Egyptian
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 or the length between the tip of little finger to the tip of the thumb (one-half cubit), the palm or width of the hand (one sixth), and the digit or width of the middle finger (one twenty-fourth). The Royal Cubit, which was a standard cubit enhanced by an extra palm—thus 7 palms or 28 digits long—was used in constructing buildings and monuments and in surveying in ancient Egypt. The
The introduction of the yard (0.9144 m) as a unit of length came later, but its origin is not definitely known. Some believe the origin was the double cubit, others believe that it originated from cubic measure. Whatever its origin, the early yard was divided by the binary method into 2, 4, 8, and 16 parts called the half-yard, span, finger, and nail. The association of the yard with the "gird" or circumference of a person's waist or with the distance from the tip of the nose to the end of the thumb of King Henry I (reigned 1100–1135) are probably standardizing actions, since several yards were in use in Britain.
There were also the rod, pole, perch and thumb for measurements of length. The following table lists the equivalents.
components | unit |
---|---|
12 lines | 1 inch |
12 inches | 1 foot |
3 feet | 1 yard |
1760 yards | 1 mile |
36 inches | 1 yard |
440 yards | quarter-mile |
880 yards | half-mile |
100 links | 1 chain |
10 chains | 1 furlong |
8 furlongs | 1 mile |
4 inches | 1 hand |
22 yards | 1 chain |
5.5 yards | 1 rod, pole or perch |
4 poles | 1 chain |
40 poles | 1 furlong |
Units of mass
The
Goods of commerce were originally traded by number or volume. When weighing of goods began, units of mass based on a volume of grain or water were developed. The diverse magnitudes of units having the same name, which still appear today in our dry and liquid measures, could have arisen from the various commodities traded. The larger avoirdupois pound for goods of commerce might have been based on volume of water which has a higher bulk density than grain.
The stone, quarter, hundredweight, and ton were larger units of mass used in Britain. Today only the stone continues in customary use for measuring personal body weight. The present stone is 14 pounds (~6.35 kg), but an earlier unit appears to have been 16 pounds (~7.25 kg). The other units were multiples of 2, 8, and 160 times the stone, or 28, 112, and 2240 pounds (~12.7 kg, 50.8 kg, 1016 kg), respectively. The hundredweight was approximately equal to two talents. The "long ton" is equal to 2240 pounds (1016.047 kg), the "short ton" is equal to 2000 pounds (907.18474 kg), and the tonne (or metric ton) (t) is equal to 1000 kg (or 1 megagram).
Units of time and angle
The division of the circle into 360 degrees and the day into hours, minutes, and seconds can be traced to the Babylonians who had a
Forerunners of the metric system
Decimal numbers are an essential part of the metric system, with only one base unit and multiples created on the decimal base, the figures remain the same. This simplifies calculations. Although the Indians used decimal numbers for mathematical computations, it was Simon Stevin who in 1585 first advocated the use of decimal numbers for everyday purposes in his booklet De Thiende (old Dutch for 'the tenth'). He also declared that it would only be a matter of time before decimal numbers were used for currencies and measurements.[1] His notation for decimal fractions was clumsy, but this was overcome with the introduction of the decimal point, generally attributed to Bartholomaeus Pitiscus who used this notation in his trigonometrical tables (1595).[2]
In 1670,
In 1790, Thomas Jefferson submitted a report to the United States Congress in which he proposed the adoption of a decimal system of coinage and of weights and measures. He proposed calling his base unit of length a "foot" which he suggested should be either 3⁄10 or 1⁄3 of the length of a pendulum that had a period of one second—that is 3⁄10 or 1⁄3 of the "standard" proposed by John Wilkins over a century previously. This would have equated to 11.755 English inches (29.8 cm) or 13.06 English inches (33.1 cm). Like Wilkins, the names that he proposed for multiples and subunits of his base units of measure were the names of units of measure that were in use at the time.[4] The great interest in geodesy during this era, and the measurement system ideas that developed, influenced how the continental US was surveyed and parceled. The story of how Jefferson's full vision for the new measurement system came close to displacing the Gunter chain and the traditional acre, but ended up not doing so, is explored in Andro Linklater's Measuring America.[5]
Metric conversion
The
See also
References
- ^ O'Connor, John J.; Robertson, Edmund F. (January 2004), "History of measurement", MacTutor History of Mathematics Archive, University of St Andrews
- Clavius and John Napier, via Bartholomaeus Pitiscus, and it developed into that used today. See O'Connor, John J.; Robertson, Edmund F. (January 2004), "History of measurement", MacTutor History of Mathematics Archive, University of St Andrewsfor this view.
- ^ O'Connor, John J.; Robertson, Edmund F. (January 2004), "History of measurement", MacTutor History of Mathematics Archive, University of St Andrews
- ^ Jefferson, Thomas (July 4, 1790). "Plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States Communicated to the House of Representatives, July 13, 1790". New York.
- ISBN 978-0-8027-1396-4.
- ^ Buchholz, Katharina (June 6, 2019). "Only Three Countries in the World (Officially) Still Use the Imperial System". Statista. Archived from the original on February 13, 2020. Retrieved April 21, 2020.
The UK is the country stuck in the middle of both systems, being the birthplace of the imperial system itself. Here, metric is partially adopted but miles persist, and people routinely refer to pints, miles per gallon, pounds and even stone in their everyday lives.
This article incorporates public domain material from Specifications, Tolerances, and Other Technical Requirements for Weighing (Handbook 44 -2018). National Institute of Standards and Technology.
Further reading
- , Measures and Weights in the Islamic World. An English Translation of Professor Walther Hinz's Handbook “Islamische Maße und Gewichte“, with a foreword by Professor Bosworth, F.B.A. Kuala Lumpur, ISTAC, 2002, ISBN 983-9379-27-5. This work is an annotated translation of a work in German by the late German orientalist Walther Hinz, published in the Handbuch der Orientalistik, erste Abteilung, Ergänzungsband I, Heft 1, Leiden, The Netherlands: E. J. Brill, 1970.
- Scales and Weights: A Historical Outline, Bruno Kisch. (New Haven: Yale University Press, 1965). Based in part on the Edward C. Streeter collection at Yale Medical Historical Library
- Kula, Witold, Measures and Men. 1986. Translated by R. Szreter. Princeton University Press. ISBN 9780691639079.
- Lugli, Emanuele, The making of measure and the promise of sameness. Chicago 2019. ISBN 9780226612492. OCLC 1051680735.