CATALOGUE OF TOLAR STARS. 



295 



Epoch. 



i 



r„ - r. 



1891 



16 



a 



+ 0.002 



1907 



32 



b 



0.206 



Whence by equations (64) 



d' a 



dt 



1 d' 



a 



2 dt' 



1 



d' 3 a 



6 



dt s 



1 



d'*a 



24 



dt* 



1 



d' 6 a 



120 dP 



s. 



+ 0.0014106 



0.000033305 



+ 0.00000093590 



+ 0.000000097911 



Epoch. 



1923 



1939 



1955 



0.0000000089646 



t 



48 



c 



64 



d 



80 



e 



Logarithms. 



7.14941 



5.9225 In 



3.97122 



2.99083 



1.95253 



r„- r. 



1/T85 



7.991 



25.308 



18 



These values of 



5 to 1955. withi 



le coefficients 

 the limits of 



eprod 



all the 



of Y — y 4 from 



second decimal place. 



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

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



we select the following values of Y 



o 







Y n given on page 281, J 



d*_a 



dt* 



and 



10 



16. 



Epoch. 



1851 



1827 

 1803 

 1779 

 1755 



Whence by equations (64) 



d' a 



t. 



dt 



+ 0.0057304 



1 d' 



a 



2 dt* 

 1 d' 3 a 



0.0051764 



6 dt 



■ 



+ 0.000015143 



t 



24 

 48 

 72 

 96 

 120 



r»- r, 



12 



a 

 b 

 c 

 d 



e 



- 0.004 

 + 0.012 



+ 0.106 

 + 0.396 



+ 1.796 



24 dt* 



1 d' 5 a 



120 dt 6 



s. 



0.00000017733 



+ 0.00000000077027 





These coefficients satisfy the values of Y — Y l2 given on p. 281 as foil 



