ON FLAMSTEED'S STAES " OBSERVED, BUT NOT EXISTING." 



77 



The next eoluiniis sbowfbe places of the same stars lioiii modern catalosni's, rcdnced to KiiX); 

 the last two coliinuis, the ilirtVrences with the Ihitisli Catalogue. The maj;nitiuU's are IVoin the 

 Diuehuiusternng and liom I'lof. A. Hall's monofiiapli ni)on this cluster. 



If we correct the right ascension of FL 1205 by —:11s, that is, if we assume witli Arijelander, 

 that on 109S, March 10, the time of transit was 8'' 27'" Jt3" instead of 8'' 28'" 'M", the af,n-eement of 

 the ])ositiou of this star with the modern determinations is perfect. Argelander's -i-iyo.2053 is 

 LL. 16939-41, Pi. 8M12, etc. 



As to Fl. 1212, the right ascension of which is quite correct, Baily afBrms from the MSS. that 

 owing to the quick succession of the star's transiting there was, on lOOO, ;\[arcii 18, some con- 

 fusion in the entry of the zeuit distances, so that opposite to this star very probably belonged 

 the reading 30o 58' 45" instead of 30° 43' 5". The star Dm. +20O.2150 is No. 05 of Professor ITall's 

 list of the stars of Prasepe. We ought to hesitate tbe less to accept the proposed corrections, as 

 Flamsteed's list thus is complete of the brighter stars of Prwsepe, but only by including these 

 two. There is no reason at all, therefore, to suspect here the disappearance of a star. 



11) 



B. Fl. 1220. 



There were observed by Flamsteed on 1703, March 11, six stars north of the zenit, which, in 

 the Historia Ccelestis, II, p. 457, stand thus : we denote them, for the sake of reference, besides 

 by the numbers of the British Catalogue, also by letters: 



Index error + 10' 10". 



The conversion of the reading per strias coclilece into arc shows, by the last two additional 

 columns, that the zenit distance jpcr lineas diagonales of the first star was read off too great by 5'. 

 The stars are easily recognized to be identical with the following: 



In order, however, to insure a good agreement the obsei'ved clock times of the lirst three stars 

 need some coirection. For the star c, which is the star put into question by Baily, we adopt 

 Argelander's very acute suggestion, that the time probably was 8^ 34°" 28% instead of S"" 28" 34», 

 Stars a and 6 were written down 1" too late, which, at least for 6 is readily conceded, the seconds 

 being 55. For more complete evidence the times thus corrected and reduced for rate of the clock 

 to some middle epoch are compared with the computed right ascensions for 1703 in the following 



