296 OUTLINES O NATURAL PHILOSOPHY. 



SECT. VI. 



FIGURE OF THE EARTH. 



298. FROM observation it has already been in- 

 ferred that the Figure of the Earth is nearly 

 that of an oblate spheroid, of which the great- 

 er axis, the diameter of the equator, is to the 

 less, the axis of revolution, as 312 to 311. 



The strict meaning of the phrase, the Figure of the 

 Earth, has already been defined, and must be 

 carefully kept in view, in searching into the causes 

 which have determined it. 



Since the Earth revolves on its axis, it is evident, 

 that its parts are all under the influence of a cen- 

 trifugal force, proportional to their distances from 

 that axis, and that if the mass were fluid, the 

 columns toward the equator, being composed of 

 parts that are lighter, must extend Mn length, in 

 order to balance the columns in the direction of the 

 axis. By this means an oblateness or\elevation at 

 the equator would be produced, similar, in some 

 degree at least, to that which the Earth has been 

 found to possess. Though it is not evident how 

 the centrifugal force would produce such an effect 



on 



