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MESURE L'ARC DU MERIDIEN 1792 by Pierre Méchain

PostPosted: Tue Jul 30, 2013 8:32 am
by Eric_Tull
Dunkerque to Barcelone

This measurement by Méchain was the point where the Metre was first defined. This is defined as 1/10,000,000 of the distance from the North Pole to the equator. However Méchain had made as small error that wasn't corrected until 200 years later. Continuing doubts about his measurements of the Dunkirk-Barcelona arc led him to return to that work after la Terreur. This took him back to Spain in 1804, where he caught yellow fever and died in Castellon de la Plana.

The length of this meridian is 390 yards short of 666 Statute Miles. We do not know the exact northern point because of WWII damage to the area. But may well have been somewhere in the piece of waste ground North of the Tower.

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GEOMETRY - literally Earth Measurement