metric system summary

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Below is the article summary. For the full article, see metric system.

metric system, International decimal system of weights and measures, based on the metre (m) for length and the kilogram (kg) for mass, originally adopted in France in 1795. All other metric units were derived from the metre, including the gram (g) for weight (1 cc of water at its maximum density) and the litre (l, or L) for capacity (0.001 cu m). In the 20th century, the metric system became the basis for the International System of Units, which is now used officially almost worldwide.

Lagrange, Joseph-Louis, comte de l'Empire

Joseph-Louis Lagrange, comte de l’Empire Summary

Joseph-Louis Lagrange, comte de l’Empire was an Italian French mathematician who made great contributions to number theory and to analytic and celestial mechanics. His most important book, Mécanique analytique (1788; “Analytic Mechanics”), was the basis for all later work in this field. Lagrange