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Metric Timeline

Today's confusion over measurement units is extremely controversial in the UK. Many people, going against the principle of a single consistent set of measurement units used for millennia, argue for the market to decide between different systems of weights and measures. Thus the history of the metric system in the UK logically belongs with any endeavours to introduce a single system of rational measurement units.

1215

Magna Carta requires "one measure" of wine, corn and cloth throughout the realm; and similarly for weights.

1670

Gabriel Moulton, in France, proposes a decimal measurement system.

1707

Treaty of Union extends English standard weights and measures to Scotland

1790

French National Assembly sends delegates to Britain, Spain and the United States to propose cooperation in units of measurement. Cooperation is rejected by Britain.

1795

Republic of France adopts French Aademy of Scences recommendation for a decimal Metric System.

1799

The platinum standards for metre and kilogram defined for decimal Metric System

1824

Weights and Measures Act phases out many traditional units and establishes the standard imperial system.

1861

A committee of the British Association for Advancement of Science (BAAS) including William Thomson (later Lord Kelvin), James Clerk Maxwell and John Prescott Joule introduced the concept of a coherent system of units which is fundamental to the modern metric system. They proposed the metre, gram and second as base units.

1862

Commons Select Committee unanimously recommends adoption of metric units for public administration.

1864

Weights and Measures Act legalises metric units only for 'contracts and dealings'.

1873

A BAAS committee proposes centimetre, gram, second (CGS) base units using prefixes from micro to mega. They also propose a unit of electrical resistance (later named the ohm).

1875

Metre Convention established by diplomatic treaty to co-ordinate world metrology. International Bureau of Weights and Measures (BIPM) established.

1881

The first International Electrical Congress adopts various BAAS recommendations on electrical units (in the metric system).

1895

Commons Select Committee recommends:

  • immediate authorising of metric units for all purposes
  • that the metric system becomes compulsory after 2 years
  • that the metric system be taught in elementary schools
1896

Weights and Measures (Metric System) Act legalises metric system for all purposes, but does not make it compulsory

1904

House of Lords votes for compulsory change to metric system, but Bill fails in House of Commons.

1939

Donaldson Committee proposes unified and metrically-based National Grid as common framework for Ordnance Survey mapping.

1951

Board of Trade committee recommends 'organised change' to metric system. Report seen as premature and not implemented.

1959

British and US inches (which were different) standardised as exactly 2.54 cm.

1963

Weights and Measures Act redefined the basic measures of the 'yard' and the 'pound' in terms of the 'metre' and the 'kilogram'. Many of the old imperial measures were abolished (drachm, scruple, minim, chaldron, quarter, rod, pole, perch, and a few more). Imperial units are now defined in terms of metric.

1965

At the request of industry. President of Board of Trade announces that the metric system will be adopted with a target of completion within 10 years (i.e. 1975). Commonwealth and other countries decide to follow Britain's example.

1968

Metrication Board established. However Board restricted to providing information and not permitted to promote benefits of the metric system.

1970

Re-surveying of UK begins to include metric elevations in Ordnance Survey maps.

1971

British currency decimalised. The much-feared changeover proved to be well organised and smooth. Massive Government information campaign to prepare the public for change.

1972

White Paper on Metrication -advocates gradual not compulsory change

1973

UK enters EEC and re-affirms commitment to adopt metric system

1974

Metric system taught in British schools. Metric packaging begins.

1979

New Government abolishes Metrication Board.

1980

Most Commonwealth countries have completed metric conversion. Britain lags behind significantly.

1988

British scientist Dr Terry Quinn appointed as Director of International Bureau of Weights and Measures (BIPM)

1989

UK negotiates derogations with EEC to secure delay in implementation of some aspects of the metric system

1995

All packaged goods sold in Britain required to be labelled in metric units. Negligible information provided to public.

2000

All goods sold from bulk are required to be measured at the point of sale and priced using metric units. Negligible information provided by Government to help public use metric units.

2004

Prof Andrew Wallard, former Chief Metrologist of UK's National Physical Laboratory becomes Director of BIPM

When will this transition end?


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