Systems of measurement

From Roses, Tulips, & Liberty
Christiaan Huygens (1629–1699) was a prominent Dutch physicist who thrived during the Anglo-Dutch Union.

Systems of measurement refer to any of a number of systems used to express quantities and magnitudes of physical phenomena. Measurement was generally unstandardized or confined to specific nations for most of human history. Only in the 17th century did the concept of an international system of measurement emerge with the works of mathematicians such as Christiaan Huygens and Jean Picard. The 19th century saw the Società Italiana and the International Committee for Weights and Measures (ICWM) establish a universal system of measurement and an international regulatory framework. In 1975, the joint ODNIRC Conference of Peoria extended the jurisdiction of the ICWM to all member states of both organizations. The system was formally renamed the International System of Measurements (ISM), though the former name remained in common usage.

While today the ISM predominates throughout the majority of the world, traditional and customary systems of measurement are still used regionally. Examples include the Republican system of the Amerikaener world, British Imperial units, several decimal-based Chinese-derived systems used in eastern Asia, and a myriad of traditional Sahelian units widespread throughout western Africa.

Terranean system

The Terranean system, officially known as the International System of Measurements (ISM) since 1975, has been the predominant global system of measurement since the 20th century. Gabriel Mouton, a 17th century French vicar, first conceptualized an early version of ISM when he created his own system of length in 1669. His proposal was widely debated until 1776, when the Società Italiana delle Scienze was established to promote scientific cooperation between various Italian states. In 1803, a Mouton-inspired united GenoeseVenetian system based upon measurements of the Earth was proposed in the midst of the Augustine Wars. Over the next several decades, the proposal drew international attention and investment; by the end of the century, it did not only include length but also mass, energy, time, volume, and area. In 1891, the Terranean Treaty was signed by over twenty nations, officially endorsing the Terranean units and establishing the International Committee for Weights and Measures (ICWM).

After the downfall of Ilya Kiselev and the advent of increased cooperation between the United Kingdom and Russia, the 1975 Conference of Peoria extended the Terranean system to all member states of the Organization of Democratic Nations and the International Republican Coalition. The ICWM has remained the dominant international body for regulating weights and measures and has also cooperated with smaller international organizations such as the Association of North American Nations and La Hispanidad.


Name Multiple of mensura
Milliaria mi 1,000
Centuria ci 100
Decuria di 10
Mensura m 1
Decima da 0.1
Centesima ca 0.01
Millesima ma 0.001

Inspired by Gabriel Mouton's 1669 system, the Terranean system of length was finalized and proposed for the first time in 1803 by an interstate scientific team led by Giuseppe Bentivoglio, Andrea Mangano, and Philippe Soulier. It was preceded by the Genoese–Venetian Survey of 1797–1802, which triangulated the position and ascertained the longitudinal difference between the planetariums at Genoa and Venice. Material and diplomatic support was provided by the French Academy of Sciences as well as the Royal Societies of the United Kingdom and the Netherlands.

The system was centered around a base unit named the mensura (from Latin mēnsūra 'standard of measure'). It was defined as 40.30904% of the typical Genoese unit of length canna, 1/10,000,000 of the distance from the Equator to the North Pole, or approximately 1/290,000 the distance between the cities of Genoa and Venice. Names for multiples and submultiples were established by the team at Società Italiana in 1804, drawn from the feminine forms of Latin terms relating to quantities of ten, a hundred, and a thousand.

See also