46 
RESEARCHES IN STELI.AR PHOTOMETRY. 
With one exception, the range in either series does not exceed 0.4 magni¬ 
tude, a rather slender basis to prove variability, thus throwing the burden of 
proof on the first observation in Hagen’s series. But this is not confirmed by 
the nearly simultaneous observations by Williams, so that the matter is left in 
doubt. An idea of the color of the stars can be obtained from the following 
summary of visual and photographic results. The visual magnitudes are photo¬ 
metric, the photographic are from a Seed 27 plate and a Cramer isochromatic 
plate. 
Star. 
Vis. 
Seed. 
Iso. 
a 
9 -15 
9.12 
9 13 
0 
8-93 
8-95 
8-95 
b 
9-53 
9-53 
9-53 
g 
11.05 
11.05 
11.05 
/ 
10.12 
9-58 
9.70 
c 
9.28 
9.80 
9.66 
The stars a, o,b, and g, with their visual magnitudes, were used as standards 
from which to obtain the photographic magnitudes of / and c. It will be noticed 
that the star c is shown to be yellow as its photographic magnitude is 0.4 to 0.5 
fainter than the visual, while the star / is blue, photographing 0.4 or 0.5 brighter 
than the visual magnitude. This is confirmed by the visual observations of Hagen 
and the writer, compared with the photographic results of Williams. 
Table 24.—W Andromeda. Standard Magnitude Stars. 
1900. 
Magnitude. 
Residuals. 
Star. 
B. D. No. 
R. A. 
Dec. 
Color 
P. DM. 
Catalogue. 
Measured. 
From Cats. 
3 
Nights 
H.C.O- 
P. DM. 
H. 
P. 
H. 
P. 
inter 
se. 
D 
O 
+ 42 
480 
h m s 
2 09 48 
O t 
+ 42 13-9 
GW- 
7.61 
8.14 
7-73 
8.14 
+ 12 
0 
±7 
E 
+ 42 
506 
2 16 31 
+ 43 03.6 
GW- 
7-44 
7.92 
7-44 
7.85 
0 
-7 
±2 
r 
+ 43 
474 
2 15 14 
+ 44 °8 • 5 
GW 
6.96 
7.20 
6.85 
7.26 
— I I 
+ 6 
±9 
Means.... 
7-34 
7-75 
7-34 
7-75 
± 8 
±4 
±6 
Table 25.—Comparison Stars in B. D. Catalogue. 
Star. 
B. D. 
1855. 
! Star. 
B. D. 
1855- 
No. 
Mag. 
R. A. 
Dec. 
No. 
Mag. 
R. A. 
Dec. 
0 
h 
m s 
O 
/ 
O 
h 
m s 
O 
/ 
a 
+ 43 457 
8-9 
2 
7 18 
+ 43 
45 + 
r 
+ 43 
474 
6-5 
2 
12 24 
+ 43 
56.0 
0 
+ 43 460. 
9.0 
2 
7 51 
+ 43 
54-3 
P 
+ 43 
478 
8.0 
2 
12 53 
+ 43 
36.6 
b 
+ 43 461 
9-5 
2 
8 21 
+ 43 
41.6 
<1 
+ 43 
482 
8.2 
2 
14 11 
+ 43 
43 -1 
c 
+ 43 462 
9-5 
2 
8 37 
+ 43 
37-5 
