GREAT REFRACTING TELESCOPE AT ELCHIES, IN MORAYSHIRE. 



407 



indication be slow binaries ; and the micrometer measures fully considered would 

 appear to tend towards the same conclusion, with the addition that the motion is 

 direct on the whole, but largely perturbed by an accompanying dark body. This 

 latter interesting result is somewhat strengthened by reference to Struve's indi- 

 vidual observations, which are thus : — 



Pos. 



312 12 



Dist. 



8-78 



Date 1828-71 



312 30 





8-71 



1828-72 



314 





8-29 



1829-84 



313 36 





815 



1832-76 



312 30 





8-43 



] 832-79 



312 12 





8-50 



1833-78 



And where, though the discordance of the H2 observation of 1829-63 cannot be 

 altogether explained, yet the mass of it is seen to occur agreeably with Struve's 

 largest position. No such large disturbances have been observed lately, it is true ; 

 but then, as the period of perturbations would seem likely to be something very 

 short, as five or ten years, it is quite possible that the crucial points of the orbit 

 have been passed over, unattended to, so few and far between have been the 

 modern observations. 



(22.) a AQUIL^, R.A. 19^ 44'° 2^, and Decl. + 8° 30' 5", January 1, 1862. 



°™I \ A Colour. Position. Distance. Date. Authority, 



ponents. tude. ■' 



B ... ...... AB 334 44 1(4)3-40 1781-56 ff 



A ... 



B ... AB 326 6 15371 1821-85 



A ... 



B ... AB 325 48 15337 1823-11 H, and S. 



A 1-5 Pale yellow 



B 10-0 Violettint AB 323 6(w/8) 152-6 (w 5) 1834-81 Cycle. 



A 1-5 Yellowish white 



B 10-2 AB 322 6 152-37 1836-29 2. 



A ... Pale yellow (1) 



B ... Grey(l) - 1856-68 AltaVista. 



'a 1 (2) Yellowish white (2) .. 

 B 10-5(2) Reddish white (2).... AB 316 0(wl) 155-75 (w/ 0-5) 1862-73 Elchies. 



In Magnitude, probably steady. 



In Colour, also probably steady, the apparent reddening of the companion 

 being explainable under the hypothesis given at pages 874 and 402. 



In Position and Distance, some uncertainties have hitherto prevailed. It is a 



VOL. XXIII. PART II. 5 S 



