What is the metric system timeline?

Answer 1

The metric system is a decimal system, that is it is based on tens, so a history of metric has to be a history of decimal systems.

Decimals were first advocated by the Flemish mathematician Simon Stevin in 1558. Before this decimal fractions were only used by a few mathematicians Stevin showed how calculations were easier using decimals, and advocated their use in everyday life, including a decimal currency. This lead to John Napier developing his logarithms.

The first decimal system of measurement was proposed by John Wilkins, secretary of the Royal Society in London, in 1668. Two years later in 1670 the French scientist Gabriel Mouton suggested a decimal system with units based on decimal fractions of the circumference of the earth.

On the 14th of July 1789, the Paris mob stormed the Bastille initiating the Great French Revolution. In the immediate aftermath the nobility surrendered their control of local systems of weights and measures. King Louis XVI summoned a group of experts, including Lavoisier and Condorcet, to establish a universal replacement for local systems. There was a belief that the new system should be for all people at all times, and not the property of one country, so approaches were made to the British and American governments for help in defining the metre. In July 1790 Thomas Jefferson presented a report to the US congress advocating adoption of a metric system, in February of the same year John Riggs Miller placed a similar proposal before the UK parliament. However when the revolution executed the king and declared a republic most international support was lost.

In 1795 the French government defined five units.

• he metre, for length - defined as being one ten millionth of the distance between the North Pole and the Equator through Paris
• The are (100 m2) for area [of land]
• The stère (1 m3) for volume of firewood
• The litre (1 dm3) for volumes of liquid
• The gram, for mass - defined as being the mass of one cubic centimetre of water

Previous definitions of the metre had been based on the length of a pendulum with a half-period of one second.

The length of the metre was established by a survey of the Paris meridian between Dunkirk and Barcelona, carried out by Pierre Méchain and Jean-Baptiste Delambre from 1792 to 1798.

The metric system using this metre was officially adopted by France in 1799, and became the sole legal system in 1801.

The Napoleonic empire carried the metric system across Europe, but most states reverted to a pre-metric system on the defeat of Napoleon.

The Netherlands re-adopted the metric system in 1817.

In 1845 the Kingdom of Piedmont and Sardinia passed legislation to introduce the metric system within five years. By 1860, most of Italy had been unified under the King of Sardinia Victor Emmanuel II and the metric system became the official system of measurement throughout the Italy.

In 1849 metric became the legal system in Spain.

In 1872 the newly established Germany adopted the metric system.

In the UK adoption of the metric system was proposed by a Royal commission in 1818, and again by parliament in 1824 by Sir John Wrottesley. A second royal commission in 1838 advocated a staged adoption , with a move to decimal coinage first, as did a third in 1853. The first decimal coin, the florin one tenth of a pound, were struck in 1849. In 1863 the House of Commons passed a law mandating the use of metric throughout the British Empire, but the bill was timed out in the Lords. In 1864 Metric was given equal legal standing with the Imperial measures. In 1895 a parliamentary committee recommended compulsory adoption of metric. In 1904 a bill passed the House of Lords making metric mandatory, but was timed out in the commons. In 1965 the UK officially began converting to a solely metric system.

In 1866 the USA adopted the metric system as a legal alternative to customary units.

In 1861 the British Association for Advancement of Science (BAAS) including William Thomson (later Lord Kelvin), James Clerk Maxwell and Joule began work extending the metric system into electricity and other scientific measurements. Their work lead to the adoption of CGS (centimetre-gram-second) system of units.

In 1875 the international Metre Convention was established to govern the control of the definitions of metric units.