PHYSICAL ASTRONOMY. 305 



surement of contiguous arches of the meridian, 

 even where the work has been conducted with 

 the greatest skill and accuracy. 



This is exemplified in the great arch of the meridian 

 measured across France ; and in those measured 

 in England and Hindostan. The cause may be 

 something concealed under the surface, which can 

 at present only be a subject of hypothetical, or, at 

 best, of analogical reasoning. 



These irregularities are so considerable, that the 

 spheroid which agrees best with the degrees in 



France, is one having an ellipticity of - , near- 



ly double of what may be accounted the mean el- 

 lipticity. 



308. Notwithstanding these irregularities, the 

 figure of the Earth has made such an approxi- 

 mation to the spheroid of equilibrium, as indi- 

 cates either the original fluidity of the entire 

 mass, or the gradual acquisition of a spheroidal 

 figure in consequence of the repeated waste 

 and reconsolidation of the parts near the sur- 

 face. 



VOL. II. U If 



