GouE — A Catalogue of Binary Stars, 8fc, 597 
round the apoastron end of the orbit since 1844. Although the change 
in position angle has been only about 52°, there has been a change in 
the mean anomaly of nearly 146°. A recent measure is — 
1888- 26 : 214°-30 : 0"'77, Schiaparelli. 
29. IBootis— 
1889- 615: 249°-9 : 3"-306, Mslw {Ohservatori/, 
ISTov. 1890). 
1890- 409 : 246 -2 : 3 -15, „ 
31. 7] Coronae Borealis = 1937— 
1887-427 : 186°-6 : 0"-82, Hough (^.iV., 2978). 
38. ^Herculis— 
1889-64 : 7r-8 : r'-55, Hough {A.JST., 2978). 
42. 2 2173. Owing to the high inclination of the real orbit, the 
apparent orbit is a very elongated ellipse. 
43. fx Herculis. Other measures are : — 
1882-54 : 258°-9 : 0''-87, Hough 2978). 
1889-51 : 357 -9 : 0 -55, Burnham {A.W., 2957). 
45^?. 99 Herculis = A. C. 15. A binary star discovered by Alvan 
Clark, at Dawes' Observatory, in 1859. As the distance is now small, 
and the companion very faint, the object is at present beyond the 
reach of all but the largest telescopes. My orbit represents the 
measures fairly well. The minimum distance seems to have occurred 
about 1885-50, when the position angle was 156°-75, and the distance 
about 0"-18. The distance is now increasing. Some recent measures 
are : — 
1881-43 : 29°-4 : 0"-51, Burnham {A.JV., 2957). 
1888*733 : Single with 36-inch refractor, Burnham. 
1889- 502 : 281°-2 ; 0"-65, Burnham {A.W., 2957). 
1890- 45 : 285 -1 : 0 '56, ,, {private letter). 
46. ^ Sagittarii — 
1886-772 : 271 -9 : 0''-53, Leavenworth. 
1890-49 : 251 -1 : 0 '76, Burnham {private letter). 
