PRELIMINARY GENERAL CATALOGUE OF STARS FOR 1900 
274 
No. 4203. X Ophiuchi. 2 2055. 
The respective magnitudes of this close binary are 4 M o and 6“i. As the distances have always 
been less than 2" (usually less than i"6) the “mass” of light has been observed by all of the meridian- 
observers. Various orbits have been computed, showing that the period is somewhere between 200 
and 400 years. Since the form of the orbit is still very uncertain, no attempt has been made to dis¬ 
cuss the meridian-observations in conformity with some adopted orbit which shall determine the 
relative curvature of the path. But in the determination of /1 and /a', terms have been added to 
deduce empirically the effect of curvature of the adopted point of observation, so far as this effect 
can be represented by a term dependent on the square of the time. Accordingly, for the secular 
variation and for the centennial variation in p.m., the following special terms have been derived: 
in R. A., — ?oo2o in decl., + '.'004 
These terms have not been adopted, although in R. A. the term is more than twice as large as its 
probable error. Prediction for this star must be regarded as very uncertain, since it may be sur¬ 
mised that the center of gravity is probably not far from the mean between the two stars, while the 
point observed must be very near the brighter star. 
No. 4246. £ Herculis c.g. 2 2084. 
The adopted magnitudes of the two components are 2 M 8 and 6^5. In determining the position 
of the center of gravity of this rapid binary, Doberck’s orbit (A.A7., 144, s. 241) has been employed. 
This makes the period 34.5 years. The determination of relative masses of the two components is 
more definite in this than in most instances. If we call the mass of the brighter star unity, that of 
the fainter comes out. 
Mass of companion, 
Mass of companion, 
Adopted, 
.39±.04 from right-ascension 
.50±.06 from declination 
•43 ±-04 
The effect of the periodic term in the proper-motion is very clearly revealed in the residuals formed 
from the meridian-observations. If to the positions of the center of gravity at various epochs, com¬ 
puted from the catalogue-place, we add the numbers in the following table, we shall have the posi¬ 
tions of the bright star for the corresponding dates. Multiplying the numbers of the table by —1.33, 
and adding as before, we have the position of the fainter star. 
Date. 
Aa. 
A8. 
Date, 
Aa. 
A8. 
Date. 
Aa. 
AS. 
1870 
+ 
s 
.007 
// 
+ - 3 2 
1890 
s 
-.034 
// 
— .l6 
1910 
S 
-.015 
ft 
+ .32 
1871 
+ 
.003 
+ •34 
1891 
-.031 
-.19 
1911 
— .018 
+ .29 
1872 
— 
.001 
+ •35 
1892 
— .028 
— .21 
1912 
— .021 
+ .27 
1873 
— 
.005 
+ •34 
1893 
.024 
-•23 
19 1 3 
-.025 
+ .24 
1874 
— 
.009 
+ •34 
1894 
— .019 
-.24 
1914 
— .027 
+ .22 
1875 
— 
.013 
+ - 3 2 
1895 
— .012 
-•23 
1915 
-.030 
+ .19 
1876 
— 
.016 
+ - 3 1 
1896 
— .006 
— .22 
1916 
-.032 
+ •15 
1877 
— 
.020 
+ .29 
1897 
+ .003 
-•17 
i 9 r 7 
-•034 
+ .12 
1878 
— 
.023 
+ .26 
1898 
+ .009 
— .10 
1918 
-•035 
+ .08 
1879 
— 
.026 
+ •23 
1899 
+ .015 
— .02 
1919 
-.036 
+ .04 
1880 
— 
.029 
+ .20 
1900 
+ .017 
+ .09 
1920 
-•037 
+ .01 
1881 
— 
•031 
+ •17 
1901 
+ .017 
+ .17 
1921 
-•037 
-•°3 
1882 
— 
•033 
+ .14 
1902 
+ .Ol6 
+ .23 
1922 
-•037 
-.07 
1883 
— 
•034 
+ .10 
1903 
+ •013 
+ .28 
1923 
-.036 
— .10 
1884 
— 
.036 
+ .06 
I 9°4 
+ .009 
+ - 3 1 
1924 
-•034 
-.14 
1885 
1925 
-.032 
-.17 
— 
•037 
+ .02 
1905 
+ .005 
+ •33 
1886 
— 
•037 
— .02 
1906 
+ .OOI 
+ •34 
1887 
— 
•037 
-•°5 
1907 
-.003 
+ •34 
1888 
— 
•037 
-.09 
1908 
— .007 
+ •33 
1889 
•03s 
— .12 
1909 
— .011 
+ •33 
