130 
RESEARCHES IN STELLAR PHOTOMETRY. 
Table 78 — 7220 S Cygni. Observed Maxima and Minima. 
Elements of maximum. 1893 October 28 (J. D- 2412765) + 326d (E — 32). M — m= 162 4 - 
Maxima. 
Minima. 
23 
Date. 
Mag. 
23 
Date. 
Mag. 
% 
Corr. 
Wt. 
Corr. 
Wt. 
0. 
w 
Calendar. 
J.D. 
H. 
P. 
w 
Calendar. 
J. D. 
H. 
P. 
32 
1893 Oct. 26 
2763 
10. 10 
10.35 
— 2 
33 
32 
1893 May 19 
2603 
me 
0 
1 
33 
1894 Sept. 20 
3092 
me 
+ 1 
5 
33 
1894 Apr. 6 
2925 
me 
- 4 
2 
34 
1895 July 25 
3400 
me 
- 17 
2 
34 
1895 Feb. 15 
3240 
me 
-15 
1 
37 
1898 Apr. 16 
4396 
me 
+ 1 
I 
38 
1898 Sept.25 
4558 
me 
— 1 
4 
40 
1900 Dee. 27 
538 i 
me 
+ 8 
6 
40 
1900 July 29 
5230 
me 
+ 19 
8 
4 1 
1901 Nov. 1 
5690 
10.4 
10.6 
- 9 
I 
42 
1902 Apr. 20 
5860 
me 
- 3 
1 
42 
1902 Oct. 17 
6040 
10.2 
10.5 
+ 15 
4 
43 
1903 Mar. 26 
6200 
15.6 
15-8 
+ 13 
4 
44 
1904 July 18 
6680 
10.0 
10.3 
+ 3 
4 
45 
1904 Dec. 25 
6840 
152 
15-4 
+ 1 
13 
45 
1905 May 29 
6993 
10.06 
10.31 
+ 8 
12 
46 
1905 Nov. 18 
7168 
16.5 
16.8 
+ 3 
8 
Table 79.—Comparison of Photometric Magnitudes. 
Star. 
H. C. 0 . 
Vol. 37. 
H. M. 
Park- 
hurst. 
J. A. Parkhurst. 
Star. 
H. C. 0 . 
Vol. 37. 
H. M. 
Park¬ 
hurst. 
J. A. Parkhurst. 
H. 
P. 
H. 
P. 
a 
7.78 
7-93 
7-53 
7.78 
/ 
11.19 
10.53 
10.78 
c 
8.76 
8.99 
8-54 
8.79 
m 
11.62 
10.73 
10.98 
d 
9.18 
925 
8.98 
9 23 
0 
12.14 
11.32 
n -57 
e 
9-43 
9.66 
9-39 
9.64 
X 
12.90 
n -95 
12.20 
/ 
.... 
10.27 
9.87 
10.12 
y 
13.48 
12.31 
12.56 
Fig. 27.— Mean Light-Curve of S Cygni. 
