SEQUEL TO THE EPOCH OF NEWTON. 237 



the fixed stars. On the application of a more 

 powerful telescope, it was seen magnified, and two 

 days afterwards he perceived that it had changed 

 its place. The attention of the astronomical world 

 was directed to this new object, and the best astro- 

 nomers in every part of Europe employed them- 

 selves in following it along the sky 30 . 



The admission of an eighth planet into the long 

 established list, was a notion so foreign to men's 

 thoughts at that time, that other suppositions were 

 first tried. The orbit of the new body was at first 

 calculated as if it had been a comet running in a 

 parabolic path. But in a few days the star de- 

 viated from the course thus assigned it : and it was 

 in vain that in order to represent the observations, 

 the perihelion distance of the parabola was in- 

 creased from fourteen to eighteen times the earth's 

 distance from the sun. Saron, of the Academy of 

 Sciences of Paris, is said 31 to have been the first 

 person who perceived that the places were better 

 represented by a circle than by a parabola: and 

 Lexell, a celebrated mathematician of Petersburg, 

 found that a motion in a circular orbit, with a 

 radius double of that of Saturn, would satisfy all 

 the observations. This made its period about eighty- 

 two years. 



Lalande soon discovered that the circular mo- 

 tion was subject to a sensible inequality : the orbit 

 was, in fact, an ellipse, like those of the other 



30 Voiron. Hist. Ast. p. 12. 31 Ib. 



