Gore — On Knoivn Variable Stars. 207 



in44'4 or 4r86 single periods." He gives the following formula for 

 the calculation of the time of Maximum : — 



1843, Sept. 20^-26 + 387-394 E + 33-9 sin (8°-6 E + 170° 20'), 



which, however, he considers must be further corrected by future ob- 

 servations. 



The following Maxima were observed by Schmidt {Ast. Nach. 

 Nos. 2171 and 2240) :— 



Mean max., 1877, Sept. 14 — Period since last Max. = 386 days. 

 „ „ 1878, Oct. 5— Period, 385-6 days. 



188. T Ceti.— Observed as 9-7 m. by Peters, 1879, September 11 

 and 12, while making observations for the minor planet Chryseis 

 (No. 202), but missed by him, 1880, September 2 and 23. On the 

 following dates he again found it visible, and compared its brightness 

 with some neighbouring small stars : — 1880, October 31, November 5, 

 9, and 26, 



189. R Cassiopeia. — From 12 observed maxima, Schonfeld con- 

 siders that the period is certainly decreasing. Assuming a constant 

 period he gives the Elements : — 



Max. Ep. E. = 1866. 4. 7-9 + 427<*-6 E ; 



but this increases the greatest deviation from 9 to 17 days. A 10 m. 

 star np. the variable. 



190. TJ Cassiopeia. — This is No. 658 of Birmingham's Catalogue 

 of Red Stars. Birmingham's Estimates of Magnitudes, 1873 to 1877, 

 vary from 7 to 8|- or 9. "Webb rated it 9-7, 1874, January 10, and 

 9 m., January 12. Birmingham says : — " This star is certainly vari- 

 able, as Secchi also has remarked." It has a blue star near it, similar 

 to U Cygni. 



NOTES ADDED IN THE PRESS. 



13. R Aeietis. — Erom a discussion of the observations of maxima 

 and minima since 1859, Baxendell deduces a period from the maxima 

 of 186-71 days (Epoch, 1866, September, 1-3), and from the minima, 

 186-63 days (Epoch, 1870, January, 2*3), and finds that the mean 

 interval from minimum to maximum is 87*7 days, and from maximum 

 to minimum 99 days. 



