Mètre

Mètre, the basis of the 'metrical' or modern French system of weights and measures, and the unit of length. The first suggestion of a change on the previous system dates as far back as the time of Philip the Fair; but up till 1790 no important change had been effected. On the 8th May 1790 proposals were made by the French government to the British, for the meeting of an equal number of members from the Academy of Sciences and the Royal Society of London, to determine the length of the simple pendulum vibrating seconds in N. lat. 45° at the level of the sea, with the view of making this the unit of a new system of measures. The British government, however, did not give this proposal a favourable reception, and it fell to the ground. The French government, impatient to effect a reform, obtained the appointment by the Academy of Sciences of a commission composed of Borda, Lagrange, Laplace, Monge, and Condorcet, to choose from the following three, the length of the pendulum, the fourth part of the equator, and the fourth part of the meridian, the one best fitted for their purpose. The commission decided in favour of the last—resolving that the $\backslash frac\{1\}\{10000000\}$th of a quadrant of the Meridian (q.v.) be taken for the basis of the new system, and be called a 'mètre.' Delambre and Mechain were immediately charged with the measurement of the meridian between Dunkerque and Barcelona; and the result of their labours was referred to a committee of twenty members, nine of whom were French, the rest having been deputed by the governments of Holland, Savoy, Denmark, Spain, Tuscany, and the Roman, Cisalpine, Ligurian, and Helvetic republics. By this committee the length of the mètre was found to be 443.296 Parisian lines, or 39.3707904 English inches; and standards of it and of the kilogramme (see GRAMME) were constructed, and deposited among the archives of France, where they still remain. If we call the mètre 3 feet $\backslash frac\{3\}\{8\}$ inches our error will be $\backslash frac\{1\}\{40\}$ inch only. The 'metrical system' received legal sanction 2d November 1801. The following are the fractions and multiples of the mètre:

The term 'metric system' is also extended to the French square measure based on the Are (q.v.), which is a square the side of which is ten metres; to the measure of weight based on the Gramme (q.v.), which is the weight of a cubic centimètre of distilled water; to the measure of capacity based on the Litre (q.v.), the volume of a cubic decimètre; and to the cubic measurement based on the Stère (q.v.), which is a cubic mètre. See DECIMAL SYSTEM.