1882.] 



285 



[Lewis. 



At 13.10 A. M., and during the half-hour following, occurred the most 

 magnificent sight of the evening, to which no description can do justice. 

 The streamers, Avhose mass was now concentrated in the corona, had de- 

 tached themselves from the northern horizon to form an auroral curtain of 

 great beauty. The curtain hung some twenty degrees above the horizon, 

 and was continually changing in form and color. The streamers, whose 

 lower ends formed its fringe, were , united above in bright hyperbolic 

 or magnetic curves, which approached the corona within ten degrees, and 

 which remained constant while the lower part of the curtain waved to 

 and fro in waves of light. 



The following very rough diagram may serve to illustrate the general 

 positions of the corona and curtain : 



W 



Fig. 1. Aurora at 12.10 a. m. 

 A line passing through the centre of the corona and Polaris was the 

 transverse axis of the hyperbolic curves, of which a mere suggestion is 

 made in the diagram. 



