CHAPTER IV. 
787 W ANDROMEDA. 
R. A. 2 h 11“ 14 s .1; Dec. +43° 50' 26" (1900). 
This is another of Anderson’s discoveries, announced in the Nachrichten under 
date January 8, 1898. Observations began at once with the star on the descending 
branch of the light-curve. The first minimum was below the limit of the 6-inch, 
but the following maximum was well covered and the second minimum was ob¬ 
served with the 12- and 40-inch telescopes, then followed occasional observa¬ 
tions, frequent enough to fix the number of the epoch, till the minimum and 
maximum of 1904 and 1905, for which more numerous observations were made. 
Comparing with the earlier dates the period 396 days was found and the mean 
light-curve deduced, using comparisons up to February 25, 1905. The subsequent 
maximum, 1905 May 31, indicates a slightly longer period, perhaps 397 days. 
The characteristic features of the light-curve are: first, a large range, from 
about 7th to fainter than 13th magnitude; second, a steady variation, unbroken 
by secondary curves, therefore the normal points from Table 31 lie close to the 
mean light-curve. 
The comparison star c has been suspected of variability by Hagen (A. N. 164 , 
79),and confirmatory observations are given by Williams (A. N. 164 > 37 1 )- Pro¬ 
visional magnitudes were published by the writer in A. J. 24 , 25. To give an 
idea of the possible variation, these are summarized below, Williams’ observations 
being reduced to magnitudes by assuming his star a (my b) to be 9.53, and his 
star b (my /) to be 9.57. 
Hagen. 
Williams. 
Parkhurst. 
Date. 
Mag. 
Date. 
Mag. 
Date. 
Mag. 
1900 Nov. 12 
9-9 
1900 Dec. 13 
9-55 
1899 Feb. 6 
9-5 
1901 Feb. 6 
9.2 
21 
9.70 
Oet. 18 
9-5 
10 
9.2 
1901 Jan. 14 
9.60 
23 
9-4 
Oct. 15 
9.2 
Feb. 13 
9 38 
28 
9-3 
Nov. 21 
9.2 
i 5 
9-42 
Nov. 4 
9.2 
1902 Oct. 8 
8.9 
1902 Jan. 31 
9.68 
1900 Feb. 16 
9.6 
1903 Sept. 22 
8.8 
Dec. 29 
9.62 
1902 Feb. 4 
9.27 
24 
8.8 
3 i 
9.70 
Mar. 4 
9.14 
Oct. 20 
8.8 
27 
9.20 
Nov. 18 
8.9 
Oct. 29 
913 
1903 Nov. 17 
9.24 
18 
9-31 
19 
9.26 
Dec. 6 
923 
21 
9.40 
Nov. 11 
9-15 
1904 Oct. 30 
9.19 
45 
