CATALOGUE OF POLAR STARS. 



295 



Epoch. 



r.-n 



120 dt"" 



These values of the coefficients will reproduce all the values of Ya—Yi from 

 1875 to 1955, within the limits of the second decimal place. 



As a further illustration of the degree of approximation to which the correspond- 

 ence of the exact values Yq with the results given by equations (64) can be carried, 



d*(t , 

 we select the following values of Yq — Y^ given on page 281, J— , and lo = 16. 



Epoch. 



Jo ^12 



1 d' 



-0.00000017733 



24 dt* 



— ^— = +0.00000000077027 

 120 dl^ 



These coefficients satisfy the values of Y^ — Fj, given on p. 281 as follows : 



