300 Double Stars. 



(1865-68) finds l"-075, 288°'08, establishing the binary cha- 

 racter ascribed to it by Sin. His measures also of A (or the 

 wide pair) tend to confirm Secchi's opinion that there is 

 angular motion in that quarter also, and in the same direction. 

 Should this indeed be proved hereafter to be a mutually con- 

 nected system, of three revolving suns, what a wonderful 

 instance it will exhibit of an arrangement so wholly unlike our 

 own, and so superior in magnificence, if not comparatively 

 diminutive in size ; yet governed, as far as we can ascertain, 

 by the same unchanging law. In their present position A 

 and B form an exquisite pair. Secchi (who ascribes to them, 

 by the way, a yellow and bluish tint) calls them " the most 

 beautiful of beautiful objects." They answer admirably as a 

 test for moderate-sized achromatics, with the convenience, for 

 observers unprovided with circles, of being immediately iden- 

 tified by the presence of 0. I can just separate them with a 

 power of 170, and there is a black division with 212. 



e Equulei will be noted as one of three stars in the finder — 

 those represented (but of course in a reversed position) in 

 the diagram. The central one, which is also the smallest, 

 offers nothing noticeable except its orange hue ; but the 

 further one lying np from e must be examined more closely. 

 It is— 



155. 376 P. XX. Equulei. l"-8. 286°-8. 6 and 8. Orange 

 and] purple. I fancied B pale tawny, 1865-73 : but this is 

 probably an instance of the singular uncertainty attending 

 these colours, at least to some eyes, which I have mentioned 

 elsewhere. Knott sees it lilac. Sm. calls this " an exquisite 

 pair." The very accordant measures of Z, Secchi, and Knott 

 at distant epochs, give about 2"- 13 as the distance, which must 

 have accidentally been undermeasured by Sm. It is % 2375. 



156. \ Equulei (alias 2, i. e. of Flamsteed^s notation). 2"'6. 

 225°-6. 6 and 6{-. Both white. This "lovely object," which 

 is stationary, will be found with little difficulty from the dia- 

 gram. It is somewhat remarkable that the affixer of the Greek 

 letter, whoever he may have been (not, as usual, Bayer, who 

 stops at 8), and Flamsteed should both have noted this star in 

 preference to the brighter one which lies at a few minutes' 

 distance np. If there is no suspicion of error here, it might 

 lead to the idea of variable light in the latter star, which has 

 been inserted in the diagram. X is 2 2742. 



157. 8 Equulei. 28"-2. 36°-8 (1838-59). 4\ and 11. Topaz 

 and pale sapphire. This object is inserted in consequence of 

 Mr. Knott's observation, that it is interesting from the remark- 

 able change in position and distance, owing to the proper 

 motion of the larger star. His data are 34""488. 27 0, 67 

 (1865-718). 



