CHAPTER V. 
4315 R COM A 3 . 
R. A. nh 59m 8.4s; Dec. + 19 0 20' 19" (1900). 
Discoveied by Schonfeld in 1856, this might almost be called a historic 
star, but the published observations were so fragmentary in character that more 
work was needed. The period was found to be only a few days less than a year, 
and the maximum so near conjunction with the sun that comparisons were un¬ 
certain in the twilight, while the beginning of the descending branch of the light 
curve was lost in the daylight, and it appears that no one had followed it in the 
morning sky, or continued observations through the minimum. The present 
observations, when combined into the mean curve, figure 15, cover the entire 
period, and seem to show that the time of maximum is about 20 days later than that 
found from evening observations alone. The maxima numbered 40, 41, 42, 44, 
and 48 are well covered with observations on both branches of the curve, but 
the twilight renders it difficult to fix the exact magnitude at maximum; it can 
only be stated as about 8.5, with the evidence insufficient to say whether it changes 
from one maximum to another. The minima, on the contrary, can be well fol¬ 
lowed, the three best observed, numbers 44, 46, and 49, giving a magnitude a 
few tenths brighter than 14. 
The faint stars with the Greek letters, z, and the variable were connected 
with the bright star F (B. D. + 19 0 2526) in February and March, 1900, with the 
micrometer on the 40-inch. The place of the variable given above results from 
the Berlin A. G. Catalogue position of the star F. 
4315 R COMA 3 . 
Table 33.—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. 
A 
O 
+ 18 2539 
h m s 
11 49 00 
O / 
+ 18 43-4 
WG 
7.76 
8.16 
7.89 
8.19 
+ 13 
+ 3 
± 6 
B 
+ 18 2546 
11 52 35 
+ 18 01.6 
GW 
6.91 
7.04 
6.81 
7.11 
— 10 
+ 7 
± 7 
F 
+ 19 2526 
11 58 57 
+ 19 23.1 
G- 
7.64 
8.02 
7.62 
7.92 
— 2 
— 10 
± 4 
Mean . . . 
7-44 
7-74 
7-44 
7-74 
± 8 
± 7 
± 6 
69 
