146 



SECOND VOYAGE FOR THE DISCOVERY 



1821. westward, from 4 to 6 o'clock. Early on the following morning, it was ob- 

 Decemb. served to form an arch of very bright light from S.E. to S.S.W., its centre 

 being 30° high. In its general form it was quite stationary, as indeed the 

 more perfect arches usually arc, but varied occasionally in the intensity 

 of the light, and also in its continuity. From tlie time that the daylight 

 began to leave the heavens in the afternoon, the Aurora again appeared, 

 commencing in the S. E. b. E. with very long coruscations or streamers, 

 which afterwards shot past the zenith over to the N.W. At 9 o'clock, the 

 light had become concentrated into a low arch, 4° high in the centre, well 

 defined at the lower edge, but not so at the upper. The legs were at first 

 situated in the E.S.E. and S.W.b.W. quarters, but the former gradually 

 shifted about two points more to the south. At one time in the evening, 

 and before the phenomenon had assumed the more regular arch-like form 

 above-mentioned, we observed for the space of a few minutes together the 

 same radiated appearance about the zenith as that described on the 14th. 



\ 



\ 



This changed pretty suddenly into an irregularly circular band of light, like 

 a ribbon, thus : 



or 



and then again returned to the radiated form, but neither of these appear- 

 ances continued very long. There was a great deal of the lilac tint observ- 

 able this evening, and the effect of the sheets of light in obscuring the stars 

 was again too evident to admit a doubt. 



The frequency and ill success with which we had tried the electrometer 

 made us almost despair of ever detecting any electricity in the atmosphere, 

 but on the "evening of the 13th the chain being observed to tremble very 

 much, we thought the motion might have been occasioned by this cause. 



