History of weights and measures


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The history of weights and measures is part of the field of the history of science . It starts with the earliest weights and units of measurement derived from human body parts and the natural environment.

overview

The earliest weights and units of measurement were based on the dimensions of body parts and the natural environment. Early Babylonian and Egyptian records, as well as scriptures from the Bible, show that length was first measured using the dimensions of the arm, hand, or finger. The time was after the orbital periods or rotational periods of sun , moon classified and other celestial bodies. If one wanted to compare the volume of containers such as bottles or clay jugs, they were filled with plant seeds, which were then counted. When weighing, the weight was measured with stones or seeds. The unit of weight carat , which is still used today for gemstones , was derived from the seed of the carob tree .

Our current knowledge of the early weights and measures comes from many sources. Archaeologists have salvaged some early standards that are now kept in museums. A comparison between the dimensions of a building and descriptions by contemporary authors provides further information. An interesting example of this is the comparison of the dimensions of the Greek Parthenon with the descriptions of Plutarch , from which one gets the length of the Attic foot fairly accurately . In some cases, however, only plausible theories and interpretations exist.

Units of length

The human cubit - usually that of a full-grown man - is the first measure of length reported. The oldest known example is the so-called nippur cubit from Mesopotamia; Whether a common standard can be derived from it is controversial in the professional world. The common cubit was considered to be the length of the arm from the elbow to the tip of the middle finger. It was divided into the span (span of the hand, half a cubit length), the hand width (one sixth of a cubit) and the finger (finger width, one twenty-fourth cubit). The royal or sacred cubit was seven inches or 28  fingers long and was used in the construction of buildings and monuments as well as for land surveying.

Greeks and Romans inherited the foot from the Egyptians. The Roman foot was divided into both twelve unciae (inches) and sixteen fingers . The Romans also introduced the mile of a thousand double strides , each double stride corresponding to five Roman feet .

These units of measurement were later standardized in the Anglo-American measurement system, among other things .

The stone throw or hammer throw or the arrow shot are further examples of length measures with historical significance. Bavarian fishermen and millers from (river) mills “earned” their temporary fishing or work area; A certain hunting order allowed a hunter to pursue an injured animal with a hatchet .

Weight units

Graduated cylinders for drachms and ounces, first half of the 19th century

Originally, merchandise was measured by piece or volume. When the weighing of goods began, units of weight were based on the volume of cereal grains or water. For example, in some areas the talent was about as heavy as a cubic foot of water, which is the equivalent of about 27 liters.

The grain (from the Latin granum for "grain") was the earliest and smallest unit of weight and originally a wheat or barley grain used to weigh the precious metals gold and silver . Larger units were developed to serve as both a measure of weight and a unit of currency, such as the pound , the shekel , the mark and the talent . The weight varied from place to place. Among the Babylonians and Sumerians sixty shekels were a mina , and sixty minas made a talent . A mina was about 500 grams. The Roman talent consisted of a hundred pounds lighter than the mina. Like the English Troy Pound (used for precious metals), the Roman pound was divided into twelve ounces , but these were smaller.

The metric carat , originally derived from the dried seed of the carob tree, was later set at 1/144 ounce and then 0.2  grams .

Example of diversity

Examples of the variety of dimensions in two former grand duchies before the national standardization of dimensions in the first half of the 19th century:

Grand Duchy of Baden
  • 112 cubits
  • 92 Areas or field dimensions
  • 65 wood dimensions
  • 163 fruit dimensions (volume dimensions)
  • 123 ohm or bucket measurements (liquid measures)
  • 63 serving or serving dimensions
  • 80 pound weights
Grand Duchy of Hesse
  • 40 cubits
  • 129 fruit dimensions
  • 77 Ohm measurements

The first standardizations took place nationwide in Germany, Austria and Switzerland in the first half of the 19th century. Within the Zollverein , weights were later partially harmonized throughout Germany and, with the creation of the North German Confederation and the German Reich, the metric system for all units of measure and weight was introduced nationwide and across the empire.

Units for time and angle

The division of the circle into 360 degrees (symbol: °) and the division of the day into hours of sixty minutes each with sixty seconds can be traced back to the Babylonians , who used the sexagesimal system , i.e. H. a number system with a base of 60. The advantage here is that the number 360 can be divided by a large number of numbers without a remainder (see also division with a remainder ) and you can therefore often avoid time-consuming fractions. The 360 ​​degrees could also be related to the fact that a year has about 360 days.

The unit gon (formerly: grads , symbol: g ), which divides the right angle into a hundred parts, is completely uncommon in everyday life, but is used in surveying .

A nautical line is the 32nd part of the full circle, corresponding to 11.25 degrees. The 200th part of a nautical line is called an artillery line (also: mil ) and divides the full circle into 6400 parts. An artillery line is roughly one meter at a kilometer away (or one millimeter at a meter away). This angle measurement is still used today in the military sector.

The unit radian (symbol: rad) is defined as follows: A circle sector with arc length  1 and radius  1 has angle  1. It does not matter which unit of measurement is used for radius and arc length - as long as it is the same. This definition means that a full angle  corresponds to 2 ·  π rad (approx. 6.2832).

Anglo-Saxon units of measure

With the occupation of England by the Romans, the Roman Mile came to the British Isles. Under Queen Elizabeth I , the Statute Mile was defined as 5280 feet or eight furlongs , with a furlong consisting of forty rods of 5.5  yards each.

The yard that is valid today was under Edward III. defined by law; before that it was considerably longer.

The metric system

The first well-defined metric system was introduced in France. In 1791 the intention of creating such a system was enacted by law; it was introduced in 1793 at the time of the Jacobin reign of terror . For the first time in history, an artificially developed system of measurements was introduced. The decimal metric system was introduced with the aim of creating a system of measurement “for all time, for all peoples”. The original meter that was created as a reference value was kept in Paris .

The first metric system was based on centimeters , grams and seconds ( cgs system , c for centimeter) and these units were very useful in science and technology . Later metric systems were based on meters , kilograms and seconds ( mks system ) in order to be easier to handle for practical applications, and the technical system of measurement emerged in technology and industry, which was based on the meter, kilopond (previously: force kilogram), second and degree would have. Metric units have spread around the world, initially in non-English speaking countries, but recently there too.

The metric system was slow to be adopted in France, but scientists and engineers found it desirable to adopt it as an international system. On May 20, 1875, an international treaty, the Meter Convention , was signed by seventeen states. Various organizations and laboratories were established to create and maintain a uniform system.

The metric system is simpler than the old units of measurement because units of different sizes are always smooth powers of ten of other units. This relationship between the units leads to easy conversions from one unit to another in the decimal system .

The currently prevailing form of a metric system is the international system of units . It was founded in 1954 - not yet under its current name and initially with only six basic units - and is also based on meters , kilograms and seconds , but also contains other basic units for temperature , electrical current , light intensity and amount of substance .

Typographic units of measure

The typographic point as a unit of font size was introduced by Pierre Simon Fournier in 1737 and further developed in 1755 by the brothers François Ambroise Didot and Pierre-François Didot . The Didot point (dd) was 0.376065 millimeters (the basic dimension was also here: a French foot, pied de roi ) until it was rounded off to 0.375 millimeters in 1973 for easier handling in the metric system. The new unit is often called the typographical point to distinguish it . In this system there is also the unit Cicero , one Cicero corresponds to twelve points. Four Cicero are combined into a concordance . A detailed presentation / comparison is available under font dimensions .

1886 came from the United States (Messrs. Luse & Co. Marder, Chicago ) with the invention of the Linotype - line casting machine an alternative point measure to Europe: the Pica-point (pp) has the exact size of 0.3514598 millimeters, equivalent to about 1/72 in. Analogous to the Cicero, a pica forms the next higher font size of twelve pica points.

Today “smoothed” dimensions are used in the IT sector . An inch had exactly 72.27 (pic) points, today an inch has exactly 72 DTP points (occasionally also PostScript points ). The DTP point (pt) is the only reliable quantity (currently) as a measurement on the computer. The point sizes differ somewhat between PC systems (including Linux ) and Apple Mac systems.

For historical reasons, the units of measurement mentioned above do not measure the actual letter size ( capital height ), but the so-called cone height. In lead type, the cone is the body that bears the (mostly smaller) letter.

The DIN 16507-2 used metric dimensions, the font size gradation is 0.25 mm, mm 0.05 if necessary. 1 p Didot = 0.376 mm. The cone indicates the font size.

Lists of historical weights and measures

Antiquity:

Medieval and early modern times:

Europe:

Other parts of the world:

museum

The Musée des Arts et Métiers in Paris, housed in an old monastery (60 rue Réaumur), shows numerous historical exhibits on weights and measures.

See also

Special systems still in use today:

literature

  • Hans-Joachim von Alberti: Measure and Weight. Historical and tabular representations from the beginning to the present. Berlin 1957.
  • Heinz-Dieter Haustein: Universal history of measurement , digital library volume 164, CD-ROM, Directmedia Publishing , Berlin 2007, ISBN 978-3-89853-564-9
  • Heinz-Dieter Haustein: Weltchronik des Messens - Universal history of measure and number, money and weight , de Gruyter, Berlin 2001, ISBN 3-11-017173-2 .
  • Heinz-Dieter Haustein: Sources of the art of measurement - To measure and number, money and weight , de Gruyter, Berlin 2004, ISBN 3-11-017833-8 .
  • Gerhardt Hellwig: Lexicon of the measures and weights. Gütersloh 1983.
  • Helmut Kahnt, Bernd Knorr: Old measures, coins and weights: a lexicon . Bibliographisches Institut, Mannheim 1986, ISBN 978-3-411-02148-2 .
  • Henry E. Sigerist : Weights and Measures in Medical Texts of the Early Middle Ages. In: Kyklos 3, 1930, pp. 439-444.
  • Wolfgang Trapp , Heinz Wallerus: Handbook of dimensions, numbers, weights and the calculation of time: with 100 tables , 6th, durchges. and extended edition, Reclam, Stuttgart 2012, ISBN 978-3-15-019023-4 .
  • Fritz Verdenhalven : Old measures, coins and weights from the German-speaking area. Neustadt ad Aisch 1968.

Web links

Wikisource: Weights and Measures  - Sources and full texts

Individual evidence

  1. ^ German right antiquities by Jacob Grimm, 1828 , p. 67
  2. Reliable draft of the hunting justice customary in Germany by Christian Gottlieb Riccius, 1772 , p. 346
  3. August Schiebe: Universal Lexicon of Commercial Sciences. Volume 1, Friedrich Fleischer / Gebrüder Schumann, Leipzig / Zwickau 1837, p. 421.
  4. In a list in the Berlin address book, the ratios of the "previous state measurements and weights in the new measures and weights established by the measures and weights for the North German Confederation [...] to the measures previously valid in this side of the administrative district and in the city of Berlin and weight system. ” Previous measurements and weights . In: Allgemeiner Wohnungs-Anzeiger together with address and business manual for Berlin , 1870, overview, p. 11 f.
  5. Ralf Klingsieck: From the old and the new measure of things. In: Neues Deutschland, 5./6. January 2019, p. 23