Double Stars. 215 



greenish. This ' ' beautiful miniature of a Geminorum " was 

 considered by Sm. and % to be fixed. Secchi, however, 

 believes it to be in slow motion, from a comparison of the 

 mean of his measures in 1855 and 1856, giving l //- 359, 118°"36, 

 with t% 1829-96, l"-502, 120°'75. ^ has 124°'4 in 1783. 

 ^ made both stars yellowish; Secchi yellow and blue. I have 

 remarked a very minute star, perhaps 14 mag., a short distance 

 n p '• a good test for light. 



Before leaving this neighbourhood we shall point out a 

 star about 1° np -^r. It is easily recognized as one of the 

 more conspicuous of the region, and larger than -^r, nevertheless 

 it has been omitted both by Flamsteed and Piazzi, the latter of 

 whom especially has inserted many minuter objects in the 

 immediate vicinity. Mr. Knott informs me that it appears in 

 Lalande's Catalogue as No. 37394, 6 mag., and as 7*8 mag. in 

 BesseFs Zones, whence Wolfers has concluded that it may be 

 possibly variable. Mr. Knott now judges it to be 5-f- or 

 6 mag., and remarks its peculiar whiteness ; to me, however, 

 it appears very slightly tinged with yellow. In the Urano- 

 metria Nova of Argelander it is marked as a naked eye star, 

 and he rates it 5*8 mag. A little n there are two open pairs of 

 9 mag. stars near together, forming a pretty group. 



We now return to j, or Tarazed, partly to notice its very 

 fine full yellow colour, which may be set down as Y 2 of Sm.'s 

 notation in his Sidereal Chromatics ; partly to point out a 

 curious chain of small stars a little to the S. of it, with a double 

 flexure, reminding us of Secchi' s curves in the galaxy ; and 

 partly to use it as a guide to a little pair lying a short distance 

 p, and not so much n, being the nearest considerable star on 

 that side in the finder. It is — ■ 



147. 257 P. XIX. Aquiloe. 4". 276°-5. 8 and 10. 

 White and smalt blue. A delicate object, and somewhat diffi- 

 cult for ordinary telescopes. Secchi considers it decidedly 

 optical. A little n is a pretty group of four stars, the brightest 

 of which is 253 P. XIX., 8 mag. 



About 1^° p Al Tair, a little s, is a 7-mag. star, 252 P. XIX • 

 a little further p, and rather more s, is — 



148. 241 P. XIX. Aquiloe. 26"-8. 253°'7. 1\ and 9*. 

 Pale topaz and lilac. I remarked another smaller and more 

 distant comes, and the field with a low power is rich in minute 

 points. 



Our diagram will enable us, at a future opportunity, to 

 refer to some other objects worthy of notice in this region ; at 

 present we shall only indicate one, which is not included in it, 

 and which is rapidly departing towards the sun — 



149. 15 Aquiloe. 34"-5. 206°-6. 6 and %. Yellowish 

 white and red lilac. This very fine optical pair may be 



