124 
RESEARCHES IN STELLAR PHOTOMETRY 
Table 75.—7220 S Cygni. Mean Magnitudes of Comparison Stars. 
6 -inch. 
September 3. 
September 5. 
October 1. 
Mean. 
Star. 
Mag. 
A Mag. 
Mag. 
A Mag. 
Mag. 
A Mag. 
Mag. H. 
Mag. P. 
A Mag. 
B 
7-23 
— 0.06 
7-30 
-fo.oi 
7-33 
4-0.04 
7.29 
7-54 
±0.04 
C 
7-44 
— 0.09 
7.61 
-t-0.08 
7-55 
4-0.02 
7-53 
7.78 
±0.06 
D 
7-33 
+ 0.16 
7.08 
— 0.09 
7. 10 
— 0.07 
7 -i 7 
7.42 
±0.11 
Mean . 
7-33 
7-58 
±0.07 
c 
8.62 
+ 0.02 
8.62 
-fo.02 
8.56 
— 0.04 
8.60 
8.85 
±0.03 
d 
905 
+ 0.02 
9.02 
— 0.01 
9.02 
— 0.01 
9-03 
9.28 
±0.01 
e 
9-32 
+ 0.06 
9.18 
— 0.08 
9.28 
4-0.02 
9.26 
9-5i 
±0.05 
i 
9.70 
— 0.09 
9.80 
4-0.01 
9.86 
-fo.07 
9-79 
10.04 
±0.06 
T 
9.06 
+ 0.09 
8.96 
— 0.01 
8.89 
— 0.08 
8.97 
9.22 
±0.06 
Mean 
9 -13 
9-38 
±0.04 
12-INCH. 
August 13. 
October 28. 
October 31. 
Mean. 
Star. 
Mag. 
A Mag. 
Mag. 
A Mag. 
Mag. 
A Mag. 
Mag. H. 
Mag. P. 
A Mag. 
c 
8.42 
— 0.12 
8-59 
4-0.05 
8.61 
4-0.07 
8-54 
8.79 
±0.08 
d 
903 
+ 0.05 
8.90 
— 0.08 
9.02 
4-0.04 
8.98 
9-23 
±0.06 
e 
9-38 
— O.OI 
9-44 
4-0.05 
9-36 
-0.03 
9-39 
9.64 
±0.03 
} 
9.86 
— O.OI 
9.92 
4-0.05 
9.82 
-0.05 
9-87 
10.12 
±0.04 
T 
8.97 
+ 0.11 
8.78 
— 0.08 
8.83 
-0.03 
8.86 
9 -11 
±0.07 
Mean 
9-13 
9-38 
±0.06 
l 
10.56 
+ 0.03 
10.56 
4-0.03 
10.46 
— 0.07 
IO - 53 
10.78 
±0.04 
m 
10.89 
+ 0.16 
10.71 
— 0.02 
10.60 
-0.13 
IO - 73 
10.98 
±0.10 
0 
11.36 
4-0.04 
H -35 
4-0.03 
11.25 
— 0.07 
11.32 
n-57 
±0.05 
X 
12.17 
4-0.22 
11.90 
-0.05 
11.77 
— 0.18 
11 - 95 
12.20 
±0.15 
Mean . 
11.13 
ii-38 
±0.08 
40 -INCH. 
U 
August 30. 
September 13. 
co 
Mag. 
A Mag. 
Mag. 
A Mag. 
1 
10.25 
— 0.07 
m 
10.70 
-fo.07 
10.48 
-0.15 
0 
11.51 
4-0.01 
n -43 
--0.07 
X 
11.77 
— 0.06 
ii -99 
f 0.16 
Mean. 
y 
12.40* 4- 0.09 
12.60 
4-0.29 
a 
i 
14.19 
4-0.29 
13-89 
— 0.01 
0 
y 
November 3 
Mag. 
10.39 
10.66 
n -54 
A Mag. 
January 3. 
Mag. 
11.78 —0.05 n.79 
+ 0.07. 
+ 0.03 10.67 
+ 0.04 11.53 
”•95 
13-54 
12.86 
-0.36 
-0.36 
12.28 
13-97 
14.94 
14-34 
A Mag. 
+ 0.04 
+ 0.03 
— 0.04 
-0.03 
+ 0.07 
Mean. 
Mag. H. 
Mag.P. 
A Mag. 
10.32 
10. 57 
±0.07 
10.63 
10.88 
±0.07 
11.50 
n -75 
±0.04 
11.83 
12.08 
±0.08 
11.07 
11.32 
±0.06 
12.31 
12.56 
±0.19 
13-90 
I 4 -I 5 
±0.18 
(12.86 
13.11 
....) 
( 14-94 
15 -19 
....) 
( 14-34 
14-59 
...J 
Also 3 , 1905 November 18, 15.48 and 15-73. 
