266 
PRELIMINARY GENERAL CATALOGUE OF STARS FOR 1900 
Date. 
Aa. 
A8. 
Date. 
Aa. 
AS. 
1797.16 
1846 
s 
+ .047 
+ 
ft 
.60 
1837.16 
1886 
s 
— .076 
// 
-1.85 
1798.16 
1847 
+•034 
+ 
.89 
1838.16 
1887 
— .060 
-i -75 
1700.16 
1848 
+•015 
+ 
1.05 
1839.16 
1888 
-•043 
—1.62 
1800.16 
1849 
—.007 
+ 
1.12 
1840.16 
1889 
-.025 
-1.44 
1801.16 
1850 
—.028 
+ 
1.12 
1841.16 
1890 
-.005 
-1.23 
1802.16 
1851 
—.048 
+ 
M 
b 
00 
1842.16 
1891 
+ .017 
- .94 
1803.16 
1852 
—.066 
+ 
I.OI 
1843.16 
1892 
+ ■033 
— .60 
1804.16 
1853 
- .083 
+ 
.92 
1844.16 
1893 
+ .050 
— .06 
1805.16 
1854 
—.098 
+ 
.82 
1845.16 
1894 
+ -°53 
+ .27 
i806.16 
1855 
-•113 
+ 
.70 
1846.16 
1895 
+ .045 
+ .63 
1807.16 
1856 
-•125 
+ 
.58 
1896 
+ .030 
+ .92 
1808.16 
1857 
-.138 
+ 
•45 
1897 
+ .011 
+1.07 
1809.16 
1858 
—.148 
+ 
•32 
1898 
— .Oil 
+1.12 
1810.16 
1859 
-.158 
+ 
.18 
1899 
-.031 
+1.12 
1811.16 
i860 
—.167 
+ 
•05 
1900 
-.050 
+1.07 
1812.16 
1861 
-.174 
— 
.09 
1901 
— .068 
+1.00 
1813.16 
1862 
-.181 
— 
•23 
1902 
-.085 
+ .91 
1814.16 
1863 
-.187 
— 
•36 
1903 
— .100 
“f" .80 
1815.16 
1864 
-.191 
— 
.49 
1904 
-.114 
+ .69 
1816.16 
1865 
-•195 
— 
.62 
1905 
— .127 
+ .56 
1817.16 
1866 
—.198 
— 
•75 
• 4 
1906 
-•139 
+ -44 
1818.16 
1867 
—.201 
— 
•87 
1907 
-.150 
+ - 3 ° 
1819.16 
1868 
—.202 
— 
•99 
1908 
-•159 
+ .17 
1820.16 
1869 
—.202 
— 
1.11 
1909 
— .168 
+ .04 
1821.16 
1870 
—.202 
— 
1.22 
1910 
-•175 
— .10 
1822.16 
1871 
—.201 
— 
i -33 
1911 
— .182 
- -23 
1823.16 
1872 
-.199 
— 
i -43 
1912 
-.188 
“ -37 
1824.16 
1873 
—.196 
— 
1.52 
1913 
— .192 
- - 5 ° 
1825.16 
1874 
—.192 
— 
1.61 
i 9 J 4 
— .196 
- .63 
1826.16 
1875 
-.188 
— 
1.69 
1915 
-.199 
- .76 
1827.16 
1876 
—.182 
— 
1.77 
1916 
— .201 
- .88 
1828.16 
1877 
-.176 
— 
1.83 
1917 
— .202 
— 1.00 
1829.16 
1878 
—.169 
— 
1.89 
1918 
-.203 
— 1.11 
1830.16 
1879 
—.161 
— 
i -93 
1919 
— .202 
—1.22 
1831.16 
1880 
-.152 
— 
1.97 
1920 
— .201 
-i -33 
1832.16 
1881 
—.142 
— 
1.99 
1921 
-.199 
-i -43 
1833.16 
1882 
-•13* 
— 
1.99 
1922 
-•195 
-i-s 1 
1834.16 
1883 
-.119 
— 
1.99 
1923 
-.191 
—1.61 
1835.16 
1884 
—.106 
— 
1.97 
1924 
-.187 
—1.70 
1836.16 
1885 
—.092 
1.92 
1925 
-.181 
—1.78 
No. 1979. a Geminorum m . Castor. 2 mo. 
The magnitudes are assumed to be 2^9 and 1^9 for a 1 and a 2 respectively. The extent of rela¬ 
tive motion of the components thus far measured is not yet sufficient to permit the computation of 
a reliable orbit. Nevertheless, the motion is so slow that the best of the recently computed orbits 
should afford fairly good approximations to correctly predicted relative positions for some years to 
come. Accordingly, Doberk’s orbit (A.N. Bd. 166, 5. 145) has been adopted as the basis of fur¬ 
ther computations. The problem of computing relative masses of the components from the merid¬ 
ian-observations is manifestly indeterminate. Both of the components are spectroscopic binaries 
and, under certain assumptions as to the situation of the orbital planes, Dr. Curtis of the Lick 
Observatory has found that the fainter star has a mass about six times greater than that of the 
brighter component. Notwithstanding the apparent weight of evidence in favor of some such con¬ 
clusion as that, the a priori probabilities in favor of nearer equality in the masses seem entitled to 
weight. Thus, in no case in the present work, where the material for computing the relative masses 
of the two components of a binary has been sufficient for a fairly trustworthy result, has the mass 
of a faint companion turned out to be demonstrably greater than that of the brighter star. In 
the present instance, accordingly, it has been assumed that the center of gravity is at the mean 
