22 Observations on the Measurevient of 



mcp.ced, but put in execution, tho?e parts of the plan which 

 were most difficult and most decisive. 



The results of the first measurements made of different 

 arcs on the meridian of different parts of the world, were 

 found to be pericctly conformable to the expectations of 

 Huyghcns and of Newton, and also with experiments made 

 on the vibration of the pendulum in different latitudes; 

 and they left no doubt that the earth was in fsct flattened 

 at the poles ; establishiusj thereby one point extremely in- 

 teresting in natural philosophy. 



These results, however, did not correspond with suffi- 

 cient accuracy for ascertaining with precision the degree 

 of ecceiHricity, or even the general dimensions of the earth, 

 as might naturally be expected when we consider the ne- 

 cessary imperfection of the means then employed in these 

 operations, and the great difficulties that are to be encoun- 

 tered. 



For the purpose of making a nearer approximation to 

 the true dimensions of the eartli, and of verifying former 

 measurements, it is necessary in some instances to repeat 

 them, and also to n^ake others in different situations, which 

 may he expected to be improved in proportion to the pro- 

 gress that is made in the useans of perfecting the several 

 departments of science. 



Ai the commenccn)ent of the French revolution, men of 

 science took advantage of the general impulse which the 

 human mind received in favour of every species of inno- 

 vation, or change, and ibey proposed makintr a new mea- 

 surement of an arc of the meridian in France, for the pur- 

 pose of establishing a new system of weights and measures, 

 which should be permanent, as being founded on the na- 

 ture of things. 



A comnnssion, composed of some of the most distin- 

 guished men)bers of the Academy of Sciences, was charged 

 to form the plan of these operations, which were to serve 

 as the basis of the new system. They invented new in- 

 struments, new methods, new formulas, and in shoit al- 

 most the whole of this impoitant (joderlaking consisted of 

 somethins; new in science. 



Two ceIel):Mied astronomers, Delandire and Mechain, 

 were engaged to jierform the astronomical and geodetical 

 observations, and these ihev continued as far as Barcelona 

 in Spain. The details of their operations, observations, 

 and calculations, were subsequently exammcd by a cotrt- 

 ^wittce of nicii of sciencCj many of whom were foreigners 



collcctetj 



