270 :MR. GEORGE KNOTT ON THE 



XIX. On the Variable Star R Vulpemlce. a=20^ s^"^ 

 22-95. 5=4-23° 17-2'. Ep. 1865-0. By George 

 Knott, F.R.A.S. Communicated by Joseph Baxen- 

 DELL, F.B.A.S. 



Read at a Meeting of the Physical and Mathematical Section, March ist, 1866. 



This star, which is No. 457, hour xx, in the Palermo 

 catalogue, was first recognized as variable, so far as I am 

 aware, at the Observatory of Bonn. It appears to have 

 been observed with some care by Dr. Winnecke at the 

 Pulkowa Observatory ; and in a letter to the Rev. B. Main, 

 printed in vol. xxii. of the Monthly notices of the Royal 

 Astronomical Society, p. 285, that able astronomer assigns 

 the following elements, "which represent seven maxima 

 observed in the course of three years, with reference to 

 Piazzi's estimations of magnitude in August, 1803," viz. : — 



Period = 138-6 days. 

 Epoch =1860, Not. 6. 



Having observed this star with more or less regularity 

 during the past four years, it occurred to me that it would 

 be interesting to compare the elements resulting from a 

 discussion of my own observations with those which had 

 been deduced by Dr. Winnecke. The results of this dis- 

 cussion I have now the honour of presenting to the Man- 

 chester Literary and Philosophical Society. 



Projecting my observations in the usual way, I obtain 

 ihe following dates of maxima and minima, with the cor- 

 responding magnitudes : — 



