142 ESSAYS AND OBSERVATIONS 



Because CL is to HK as CG to GH, 

 that is, as the radius to the line of the ano- 

 maly of the excentric, and HK Is to KS as 

 the fine of the true anomaly to the radius ; 

 therefore CL is to KS as the line of the true 

 anomaly to the anomaly of the excentric. 



The place of a planet in an elliptic orbit 

 [granting the quadrature of the ellipfe] may be 

 found at any given time within a fmall limit^ 

 by the following theorem. 



THEOREM. Fig. 7. 



Let the ellipfe, whole greater axis 

 is AP, foci S, K, and center C, 

 reprefent the orbit of a planet 

 round the fun at S; and, fuppofing 

 the periodic time of the planet 

 round the fun to be known, and 

 likeways the time the planet paffed 

 thro' the aphelion A: As the pe- 

 riodic time of the planet round 

 the fun, is to the time elapfed 

 fmce the planet palfed thro' the 



point 



