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VII. niPnry of jijlronomy for the Y, ar 1799. Tij .TeroME 

 L.VLANDE. Read at the Lyceum on the 26th of December, 



HTS year w ill be nicmovablc; on account of tlie totaP 

 completion of that imincnrc operation rerpoel:in2; the fize of 

 the earthy which laflcd fcven years. Thofe able aftronomers, 

 Delambre and Mcchain, Atho finidied it, arrived in the month 

 of November 1798, and by the month of Januaiy were able 

 to give us the value of the degrees between Dunkirk and 

 Barcelona. But, as thefe degrees did not follow an uniform 

 progrefs, it was foon found, that, to deduce from them the 

 value of the metre, or the new French meafure, a difciilhon 

 was neccflary, on the oblate form of the earth, to be adopted. 

 I fad they adhered to the arc meafurcd between Dunkirk and 

 Barcelona, they would have had ^--i,, or nineteen leagues, 

 for the flatnefs at the poles ; hut, by comparinc; it with the 

 degree meafurcd under the Equator, they found only nine 

 leagues and a half. 



On the 8th of April, after a long difcuffion, they adopted 

 the latter quantity, and the new metre was determined to be 

 ^6 inches 1 1*296 lines, and the flatnefs of the earth -.yr. 



On the 5th of May C. Va.n Swinden, a celebrated Dutch 

 philofopher, made a definitive report on the grand labour 

 of the meridian and the metre, which was afterwards read 

 in a public fitting of the Inftitute. 



On the 22d of .Tunc the Inftitute prefented to the twct- 

 comicils the original ftandards of the metre and kilogramme 

 of platina, which were placed in the magnificent depot of the 

 national archives in the national palace, formerly the Thuil- 

 leries. 



On tlse lyih of November the conHils propofed a law to 

 declare that the metre and the kilogramme are the definitive 

 ftandards of France, and to caufe a medal to be ftruck in 

 commemoration of this grand undertaking. On one fide i.<; 

 to be reprtfeuted the Uepublic holding the metre and the kilo- . 

 gramme, with this infcription, " To all ages and all nations ;'* 

 and on tlie exergue, •' French Republic, year 7." The 'iaure 

 will be on a pliiiih of five centimetres. The rcverfe will ex- 



hibijt 



