lohkhjbrm Biriary Systems. 43 



10. Mu Cancri, R. A. 8^ 16^ Decl. N. 25" T. 



THe stars are of tlie 7th and 8th magnitude, and seem to 

 have experienced a great change both in angle and in distance. 

 In 1783 the angle was 32*, 9' nf, and the interval only one 

 and a-half the diameter of the large star, which can hardly 

 exceed 4" from centre to centre. In Feb. 14, 1822, the angle 

 was 52° 13' 7iJ] and the distance 6".05. This gives an annual 

 motion of-— 0°.514. M. South found the difference of declina- 

 tions of the two stars 4".85. When this is computed for the 

 angle and distance observed by Messrs Herschel and South it 

 comes out 4". 78. 



11. 84 Virginis, R. A. 13^ 34'. Decl. N. 4'' 27. 



The stars are exceedingly unequal, the large one being 

 white, and the small one decidedly blue. In 1782.12 the posi- 

 tion was 29° 5' s p, and the distance 2J diameter. In 1802.31 

 the position was 30*' 1'. In 1821.33 Struve makes it 35° 54', 

 and in May 3, 1821, Messrs Herschel and South make it 40° 

 9' s p, and the distance 3".91. " The distance,'"* says Messrs 

 Herschel and South, " has certainly diminished considerably. 

 With regard to the angles one of the three positions must be 

 erroneous; and if one be correct, there is no doubt of a sen- 

 sible, or perhaps even a considerable annual motion." 



12. g Scorpiiy R. A. 15^ 54'. Decl. S. 10^52'. 



The stars are of the 4th and 8th magnitude. In 1722.3b' 

 the position was 1°, 23' w/, and distance 6".38. In 1819.5 

 Struve made it 2P nj; and the distance 9".31. In 1822.46 

 Messrs Herschel and South made it 11° 37' nf, and the dis- 

 tance 6".77. " The large star of J has not been seen double 

 by us,"" says Messrs Herschel and South. This is perhaps a 

 binary system, with a mean annual motion of — 0°.256. 



13. 59 d Serpentis, R. A. 18i^ 18'. Decl. N. 0° 5'. 



The stars are of the 7th and 8th magnitude. The large one 

 being white and the small one blue. In 1781.79 the position 

 was 44° 33' np, and the distance 1 or 1 J diameter. In 1802.34 

 it was 42° 25', and the distance 4 or 5 diameters. In 1819.61 

 Struve found it 40° &', and the distance 3".76. 1825.54 it was 



