164 Astronomical and Nautical Collections. 



The differences are 4' 51" and 2' 36", and the hourly motion 

 becomes 26' 39", instead of 31' 30"; hence 



P. L. 26' 39" 8296 



2' 36" 1.8403 



Log tang 5° 34' 8.9893 



62 2 



56 28 Visible polar orbital angle. 



29 24 



23 50 Visible parallactic orbital angle. 



iii. By means of the angles thus found, reduce the parallax 

 at the conjunction in right ascension to the visible orbit, and 

 to the direction perpendicular to it ; and reduce the difference 

 in declination to the same directions ; the sum or difference of 

 the former results, reduced into time, according to the visible 

 hourly motion, will give the time of the nearest approach 

 and the sum or difference of the latter will give the nearest 

 distance. The hourly motion may be reduced to the visible 

 orbit by increasing it in the ratio of the radius to the secant 

 of deviation. 



