THE 



QUARTERLY JOURNAL 



OF 



SCIENCE, LITERATURE, AND ART. 



Memoir on a New Calculation of the Latitudes of Montjouy 

 and Barcelona ; being a Supplement to the Base du Sys- 

 teme Metrique. — By J. N. Nicollet, of the Royal Observa- 

 tory, Paris. 



(Translated fpom the original MSS., communicated by the Author.) 



In the great work of the measurement of an Arc of the Me- 

 ridian between the parallels of Dunkirk and Barcelona, the 

 southern part of the operations, viz. that between Rhodez and 

 Montjouy, was allotted to M. Mechain. Quitting Paris for 

 Spain in June, 1792, and assisted by M. Tranchot and two 

 Spanish commissioners, M. Mechain executed, with very re- 

 markable activity and success, the observations of every kind 

 committed to his charge. Before eight months were expired 

 he had covered the space comprised between Barcelona and 

 the Pyrenees with triangles ; had completed the observations of 

 latitude and azimuth at Montjouy ; as well as many other 

 observations incidentally connected with the operations, such 

 as observations of comets, solstices, occultalions, and eclipses 

 of every kind ; and had ascertained the possibility of pro- 

 longing the arc to the Balearic Islands. 



It remained to connect the chain of triangles in Spain with 

 the nearest stations in France, and to extend the triangulation 

 to Rhodez. M. Mechain had flattered himself with the pros- 

 pect of accomplishing this in less than a year ; but the troubles 

 of the French revolution, the war which broke out with 

 Spain, and the terrible accident which happened to himself,* 



* He was struck by the handle of a machine employed in raising water at Bar- 

 celona, which broke his shoulder blade and several ribs. 



APRIL— JULY, 1828. R 



