12 
RESEARCHES IN STEEEAR PHOTOMETRY. 
which form the basis of the photometric work. The “ H. C. O.” values are taken 
from the Harvard Annals, 45 , the “ P. DM.” from Potsdam Publications, vols. 9, 
13 and 14. Then follow the measured magnitudes and residuals which result from 
Table 10, and will be considered in that connection. As all the measured magnitudes 
are based on these three catalogue stars it follows that the measured magni¬ 
tude of each star expressed in the Potsdam system will be 0.08 greater numerically 
than its magnitude in the Harvard system. 
Table 6 . —Comparison Stars in B. D. Catalogue. 
B. D. 
Oi 1 __ ___ 
1855- 
B. D. 
1855- 
OLcll . 1 
OlctI. 
| 
No. 
Mag. 
R. A. 
Dec. 
No. 
Mag. 
R. A. 
Dec. 
0 
h m s 
O / 
O 
h m s 
O / 
d +26 37 
8.8 
0 13 33 
+ 26 10.0 
e 
4 - 26 46 
9-4 
0 15 47 
4-26 22.9 
a 4-26 40 
7-5 
0 13 58 
+ 26 8.7 
c 
+ 26 47 
9 - 1 
0 15 50 
4-26 18.4 
l + 25 40 
9 5 
0 14 19 
+ 25 58.3 
/ 
+ 26 48 
9-4 
0 16 10 
4-26 12. 1 
b j 4- 26 42 
8.1 
0 14 27 
+ 26 23.4 
Table 6. As a few of the brighter comparison stars are not within the limits 
of the photographic charts, Table 6 gives the B. D. numbers, magnitudes, and 
places for 1,855 of the stars in that catalogue not in Table 5. 
Table 7.—Comparison Stars for T Andromeda (in Order of Right Ascension). 
Coordinates from Variable. 
Magnitude. 
Light 
Star. 
Scale, 
Measured. 
From Curve. 
R. 
A. 
Dec. 
Steps. 
H. 
P. 
H. 
P. 
d 
// 
— IOI7 
s 
-74.0 
tf 
~ 30 
t 
34-7 
9.12 
9.20 
<7 
a 
b 
12.2 
is. 3 
— 770 
-56.1 
-50.8 
- 49-4 
-44.9 
— 40.0 
-29.9 
+ 41 
— 122 
14 - 3 
42.0 
15 - 3 
17.1 
16.3 
- 698 
- 679 
- 617 
- 550 
- 411 
7.98 
8.06 
4 - 19 
-297 
- 173 
-873 
12.1 
12.2 
r 
n 
11.8 
11.9 
0 
11.9 
12.0 
s 
25.6 
10.32 
10.40 
T 
- 389 
- 316 
— 28.3 
4 - 85 
4-690 
10.3 
12.8 
12.9 
b 
-23.0 
39 0 
8.72 
8.80 
h 
— 290 
- 259 
— 21. 1 
- 23 
— 690 
18.9 
11 54 
11.62 
l 
— 18.9 
26.5 
10.15 
10.23 
y 
- 85 
— 6.2 
4 - 44 
14.40 
14.48 
X 
— 21 
— IS 
4-174 
+ 103 
10.0 
13.12 
13.68 
13.20 
I 3-76 
w 
4 - 30 
4 - 2.2 
u 
+ 33 
4 - 2.4 
4- 226 
.... 
13.22 
13-30 
. 
4 - 108 
+ 157 
4- 196 
4 - 7.0 
-f 62 
4- 800 
14.08 
14.16 
tn 
4-11.4 
20. 5 
11.28 
11.36 
t 
4 - 14-3 
4-420 
12.3 
11.66 
H -74 
k 
4 - 227 
+ 16.5 
4-106 
14-3 
11.85 
u -93 
e 
4 - 793 
+ 57-7 
4-659 
30.7 
10.20 
10.28 
c 
1 
4 - 835 
4- 1125 
4 - 6 o .8 
4-81.9 
4-394 
4 -118 
33-6 
29 -5 
9 - 5 i 
9-59 
9-97 
10.05 
Table 7 collects the data for position and magnitude of all the comparison 
stars used. The second and fourth columns give the rectangular coordinates from 
the variable in seconds of arc; the third column expresses the R. A. coordinate 
