The 1793 provisional meter

The first public figures for the new standard, together with the name meter, were provided by the académiciens in a report by Borda, Lagrange and Monge in spring 1793[32]. A project of decree for a general system of weights and measures, also containing the cited report, was presented to the National Assembly in July of the same year[14]. The length of the meter was obtained from the Lacaille-Cassini measurements, with the simple calculation shown in the previous subsection.

Its approximated value is 3 pieds 11 lignes 44/100 present Paris measure

[443.44 lignes]

, and this approximation is such that its error does not exceed one tenth of


ligne

[0.2 mm]

, that is sufficient for the ordinary use in the society. This unit will take the name meter. ([14], p. 5)

The so called provisional meter, with all the resulting units of volume, weights and surfaces [14,32], was adopted by decree the 1st August 1793.