By a decree on 8 May 1790, the French
National Constituent Assembly ordered the
French Academy of Sciences to develop a new measurement system. In August 1793, the French
National Convention decreed the
metre as the sole length measurement system in the French Republic and it was based on millionth of the distance from the
orbital poles (either North or South) to the
Equator, this being a truly internationally based unit. The first name of the kilometre was "Millaire". Although the metre was formally defined in 1799, the
myriametre ( metres) was preferred to the "kilometre" for everyday use. The term "
myriamètre" appeared a number of times in the text of Develey's book ''Physique d'Emile: ou, Principes de la science de la nature
, (published in 1802), while the term kilometre
only appeared in an appendix. French maps published in 1835 had scales showing myriametres
and "lieues de Poste'' (Postal leagues of about metres). The Dutch, on the other hand, adopted the kilometre in 1817 but gave it the local name of the
mijl. It was only in 1867 that the term "
kilometer became the only official unit of measure in the Netherlands to represent metres. Two German textbooks dated 1842 and 1848 respectively give a snapshot of the use of the kilometre across Europe: the kilometre was in use in the Netherlands and in Italy, and the myriametre was in use in France. In 1935, the
International Committee for Weights and Measures (CIPM) officially abolished the prefix "myria-" and with it the "myriametre", leaving the kilometre as the recognised unit of length for measurements of that magnitude. The symbol
km for the kilometre is in lower case and has been standardised by the
BIPM. A slang term for the kilometre in the US, UK, and Canadian militaries is
klick. == See also ==