>At 11:03 +0100 01/02/15, Han Maenen wrote: >>On the same day: >>In 1790 George Washington proposed a decimal system of units. >>In 1799 Van Swinden, rapporteur of the Paris conference, launched the metric >>system in a public session, when he made his report. >>1814: The status quo in France, the co-existence of the metric and the >>Napoleonic Customary System was confirmed by the king. >>1837: France goes metric for good by the "Loi du Quatre Juillet concernant >>les Poids et Mesures", starting its global spread. Han, I come back on this question of 4 July. Especially on the 4 July 1799. You say that this day, Van Swinden reported on the work of the international commission whom he chaired. This commission was set up to check the results of Delambre and Méchain who had completed the measurement of the arc of meridian so that the exact length of the metre could be determined. [Another commission chaired by Trallès from Switzerland made the determination of the mass of the kilogramme] Van Swinden presented his report on 30 April 1799 [Trallès on 30 May] Thereafter the standards of the mètre and kilogramme could be made (by Janety and Lenoir) : they were presented to the Council on 4 messidor an VII (22 June 1799) by a delegation of French and European scientists led by Van Swinden. The same day they were deposited to the Archives of the Republic. Nowhere in my documentation did I find a reference to this public session of 4 July 1799. Could you please tell me more about this public session ? Thanks Louis
