350 Dr. Brinkley’s observations for investigating 
therefore to the extent of these quantities at least, the other 
results cannot be depended on. 
The whole number of observations is 2633, and the mean 
of all the constants of aberration is 20", 37. 
TABLE II. 
No. of 
winter Ob- 
servations. 
Mean N. P. D. Jan. 1 , 
1819 , by winter Ob- 
servations. 
N.P.D. by 
summerOb- 
servations. 
No. of 
sumrnerOb- 
servations. 
x Arietis - - 
40 
0 /II 
67 23 53>43 
1 / 
53,08 
3 6 
Aldebaran - 
6 5 
73 5 1 49>35 
49,09 
3 ° 
(3 Tauri - - 
52 
61 33 21,76 
21 ,66 
38 
x Orionis 
82 
82 38 9,29 
907 
65 
Castor 
34 
57 43 29,94 
30,52 
33 
Procyon - - 
64 
84 19 8,44 
8,41 
73 
Pollux 
36 
61 32 45,00 
44,96 
29 
Regulus - - 
Spring. 
21 
77 9 7.45 
7 > 5 8 
Autumn. 
12 
(3 Leonis - - 
20 
74 24 5 7 . 9 1 
57*53 
27 
The mean of the differences of the 343 summer observa- 
tions, and of the 414 winter observations, is only of a 
second. 
