16 



remarks that if the star's variability had not been discovered 

 till that time, it would almost certainly have been regarded 

 as a single period variable. 



The observations I have made since 1879 show that the 

 reversion continued till the spring of 1883, but from that 

 time to the autumn of the present year they seem to indicate 

 that a return to the former relations of the two minima has 

 already commenced. 



The changes in the length of the period are shown as 



follows : — 



1859, Oct. 27, to 1861, Oct. 8 



1861, Oct. 8, to 1864, Aug. 30 



1864, Aug. 30, to 1866, Dec. 22.. 

 1866, Dec. 22, to 1868, Sep. 12 .. 

 1868, Sep. 12, to 1878, July 16 .. 

 1878, July 16, to 1881, Juue 12.. 

 1881, Juue 12, to 1884, Sep. 28.. 



The minima observed since September, 1868, are as follows: 



First or Principal Minima. 



Mag. Mag. 



1878, July 16—9-5. 1881, Juue 12—8-9. 

 Sep. 21-9-3. Aug. 17— 8-9. 

 Dec. 5—9-4. Oct. 24—9-0. 



1879, Sep. 3-9-4. 1882, May 26— 8-9. 

 Nov. 14-9-3. Aug. 7—9-0. 



1880, June 16—8-9. Oct. 15—9-1. 

 Aug. 29—8-9. 1884, July 16—9-4. 

 Nov. 10— 8-9. Sep. 28—9-4. 



The mean magnitude =9'14. 



Epoch = 1881, March, 29-086. 



Secondary Minima. 



mean period = 70-88 days, 

 = 70-46 

 = 70-44 

 = 69-96 

 =^70-47 

 = 70-76 

 = 70-98 



