I 



412 PROFESSOR C. PIAZZI SMYTH ON THE 



The Elchies telescope was turned upon this object, because the description in 

 the Cycle seemed so pointedly to define when the Cycle telescope stopped in 

 making out small stars, — viz. decidedly below Sir John Herschel's 20-foot re- 

 flector, — that it seemed an excellent opportunity for ascertaining whereabouts the 

 Elchies telescope, worked by an eye very probably much inferior to both the others, 

 would come. 



The Cycle describes the group as "a most delicate double star in a barren 

 field ; and that it " is No. 947 of H's 20-foot sweeps, and classed triple, having a 

 minute comes in the np, of the 17th magnitude. But this I ' (Cycle)' could not 

 manage to get a sight of, notwithstanding the coaxings exerted." 



The Elchies telescope, however, not only showed the above double-star, but 

 also Sir John Herschel's C, still existing in the relative place which he pointed 

 out ; and in addition to that, several other and previously unrecorded stars, as 

 the D, E, and F of our list ; and the truth of their finding has been since testified 

 to in an uncomplimentary, but, for the truth of a scientific fact, a most unexcep- 

 tionable manner, by the Rev. W. R. Dawes, in the Astronomical Society's 

 Monthly Notices for December 1862, page 79, paragraph 3. 



(28.) 2841 2, R.A. 21i^ 47'" 46=, and Decl. -t- 19° 2' 53", Jan. 1. 1862. 



Com- Magni- Colour. Position. Distance. Date. Authority, 



ponents. tude. 



A 65 Conspicuously yellow.. ^ ^ ^^ 



B 80 Blue ". AB 111 2 2221 182946 2. 



A 6-7(3) Yellow(3) 



B 8-7(3; Lilac(3) AB 110 58 (jc 2) 22-46 (/«/ 1) 1862-73 Elchies. 



The previous star. No. 27, the penultimate of our list, gave some fair indi- 

 cations of the abundant light-transmitting power of the Elchies telescope ; and 

 the present star, the ultimate member of the same list, happens curiously enough 

 to close our little record of the trial of Mr Grant's large telescope, with data 

 having reference possibly to the power of accuracy or agreement with standard 

 authorities in each of the four telescopic phenomena usually noted with every 

 considerable double star. 



The case would of course be infinitely more satisfactory, if there had been 

 several observations by earlier authorities to refer to, and prove thereby whether 

 this was a stationary or changing group ; but I knew of none such at the time, and 

 did not even know of this one until after I had left Elchies, and had communi- 

 cated my own measures to my friend, Professor Grant, of the GlasgOAV Observa- 

 tory, — and he discovered that they must apply to Struve's star. No. 2841. 



The whole case occurred in this manner. I had been so long one evening writ- 

 ing down some of the particulars observed about the star 312 Pegasi, that when 

 I went back to the telescope the equatorial driving clock had run down, and the 

 star was gone. But on looking through the chief finder, lo ! there was in its place 



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