ADVERTISEMENT. XXlll 



new degrees of evidence, by it's extenfion to the 

 different harmonies of Nature. 



Let us colled:, for this purpofe, the proofs which 

 lie fcattered about in the preceding Volumes. 

 Some of them are geometrical, fome geographical, 

 fome atmofpherical, fome nautical, and fome aftro- 

 nomical. 



I. The firft proof, of the elongation of the 

 Earth at the Poles, is geometrical. I have infert- 

 ed it in the explanation of the plates, at the begin- 

 ning of Volume Firft ; it alone is fufficient to fet 

 the truth in queftion in the cleareft light of evi- 

 dence. There was no occafion even for a figure 

 in order to this. It is very eafy to conceive that 

 if, in a circle, the degrees of a portion of this 

 circle lengthen, the whole portion containing thefe 

 degrees, mud likewife lengthen. Now, the de- 

 grees of the Meridian do lengthen under the polar 

 Circle, as they are greater there than under the 

 Equator, according to the Academicians; there- 

 fore the polar arch of the Meridian, or, which is 

 the fame thing, the polar curve lengthens alfo. 

 I have already employed this argument, to which 

 no reply can be given, to prove that the pC'Ur 

 curve was not flattened ; I can eafily employ it 

 likewifç to prove that it is lengthened out. 



b 4 II. The 



