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CHAPTER V. 



SEQUEL TO THE EPOCH OF KEPLER. RECEPTION, 

 VERIFICATION, AND EXTENSION OF THE ELLIPTI- 

 CAL THEORY. 



Sect. 1. Application of the Elliptical Theory to 

 the Planets. 



THE extension of Kepler's discoveries concern- 

 ing the orbit of Mars to the other planets, 

 obviously offered itself as a strong probability, 

 and was confirmed by trial. This was made in 

 the first place upon the orbit of Mercury ; which 

 planet, in consequence of the largeness of its eccen- 

 tricity, exhibits mere clearly than the others the 

 circumstances of the elliptical motion. These and 

 various other supplementary portions of the views 

 to which Kepler's discoveries had led, appeared in 

 the latter part of his Epitome Astronomies Coper- 

 nicance, published in 1622. 



The real verification of the new doctrine con- 

 cerning the orbits and motions of the heavenly 

 bodies was, of course, to be found in the construc- 

 tion of tables of those motions, and in the con- 

 tinued comparison of such tables with observation. 

 Kepler's discoveries had been founded, as we have 



