402 PROFESSOR C. PIAZZI SMYTH ON THE 



In Character, an optical pair, experiencing much proper motion relatively. 

 Comparing the mean of the Cycle and 2 with the Elchies observation, and 

 computing therefrom the annual proper motion of A upon B, it comes out 



In R.A. - 0"-60, and in D. + 0"-76 ; 



the British Association quantity for A being 



In R.A. - 0"56, and in D. + 0"-65. 



(16) a LYR^, R.A. l^" 32™ 14^, and D. + 38° 39' 8", January 1, 1862. 

 I , ^5 ' Colour. Position. Distance. Date. Autiiority. 



B ... AB 116 14 42-99 1792-32 H^. 



A 



B ... AB 132 7 42-11 1822-87 H2 and S. 



A 1 Bluish white 



B 10-5 AB 137 51 42-96 1836-14 2. 



A 1 Pale sapphire ... 



B 11 Smalt blue AB 140 18 (w 9) 434 (m;9) 1843-34 Cycle. 



A ... White 



B ... Violet 1856 58 Guajara. 



j' White, with spuri- 

 A 1 (2) -; ous outer violet 



( rays (3) 



B 11(1) Reddish lilac (3) AB149 38(w2) 4591 (t<; 1) 1862-73 Elchies. 



In Character, an optical pair, influenced relatively by proper motion. 



In Magnitude, probably steady ; but I could say little else of A at Elchies, 

 than that it was the most gorgeous, glorious, and brilliant star I ever had the 

 privilege of beholding in a telescope, and there was nothing else with which I 

 could approximately compare it. 



In Colour, they may also be steady ; for, as to the reddening appearance of B 

 at Elchies, it may have been an ocular effect, in deference to the spurious out- 

 side violet rays of the great star A. (See p. 374.) 



In Position and Distance^ the Elchies measure being compared with the mean 

 of Struve's and the Cycle, gives for the annual proper motion of A upon B 



In R.A. + 0"-28, and in D. + 0"-30, 



while the British Association Catalogue gives for A 



In R.A. + 0"-30, and in D. + 0"-28. 



an unexpectedly close approach. 



