202 Proceedings of the Royal Irish Academy. 



3 ; 1880, September 24, and November 23 ; and easily yisible on the 

 following dates, -when he compared its brightness "with that of neigh- 

 bouring small stars : — 1878, August 22, 29, September 2, 19, and 21, 

 and October 1 and 16 (ganz hell) ; 1879, July 15, September 11 and 

 20, and October 6; 1880, July 15 and 18, August 16, 26, and Sep- 

 tember 10. He deduces a period of 326 days, with a maximum in the 

 latter half of July, 1880 (AJS" 2360). 



173. X Capeicoeni. — Discovered to be variable by Prof. Peters at 

 Clinton, TJ. S. A., from observations, 1871-1880. He found it invi- 

 sible in his telescope on the following date : — 1871, July 12. And 

 visible on the following dates, when he compared its brightness with 

 small stars in the vicinity: — 1871, July 16 ("bemerkt wie ein sehr 

 schwaches Piinktchen") ; 1872, July 2 and 12 ( " kaum sichtbar " ) ; 

 1875, August 25; 1876, July 16 ("hell"), 21, and 26, September 

 8, ]S"ovember 5 ("niir eben sichtbar sehr schone Luft"); 1877, 

 November 7; 1878, August 2, 29, September 2, 19, 21, October 1, 16 

 ("sehr schwach"); 1879, July 15, September 11, 20, October 6 

 ("sehr klein"); 1880, July 15, August 16, 26, September 10, 24 

 ("hell"), and November 23. 



He deduces a period of 217 days, with a Maximum about the end 

 of September, 1880. 



174. 63 Cygni. — A variable of long period, discovered by the Eev. 

 T. E. Espin, who assigns a variation of 4-7 m. + to 6-0 m. + with a 

 period of about 5 years from minimum to minimum. In January, 

 1878, it was about 6*0 m. With the exception of some slight fluc- 

 tuations, it increased in light till, in November, 1881, its magnitude 

 was 4"7. On May 4, 1882, it was as bright; but on August 8, it 

 seemed to have lost light ; and on August 11, 1882, it was about 5'0 m. 

 On January 15, 1883, it had fallen to 5*6 m., since which it has again 

 increased in light {Mon. Not. R.A. S., March, 1883). 



I observed this star to increase in light from 5-0 m. on 4th March, 

 1883, to 4-8 m. on 10th May, 1883. On 13th August, 1883, I esti- 

 mated it 5-0 m. (57 Cygni = 5-3 m.) ; 17th August, 1883, 5-0 m. ; 

 4th September, 1883, 5-0 m. ; 6th December, 5-0 m. ; 30th Decem- 

 ber, 5*0 m. 



175. T Cephei.— This star is D M 67°, 1291. The following 

 maxima and minima were observed by Knott : — 



Min., 1881, June 18, mag. 9-5. 

 Max., 1882, January 13, mag. 6*4. 

 Min., 1882, July 23, mag. 9-8. 



The interval between the minima is 400 days. 



A maximum was observed by Schmidt, 1882, January 11, mag. 6-7. 



