264 Mr. Christie on the Aurora Borealis 



8th January. Later in the evening the northern arch in- 

 creased in distinctness, the upper circumference being very 

 well defined, and below there was another luminous arch, in 

 the interior of which was a dark segment 10 or 12 in alti- 

 tude. The magnetic north still appeared to be the centre of 

 these arches ; only very faint streams proceeded from the 

 upper arch. The strongest light was at the two ends, towards 

 the east and west. This was the appearance at 9h. 30m. ; at 

 9h. 50m. three concentric arches were distinctly visible, their 

 highest points being still in the magnetic meridian; at 

 lOh. 45m. there was a single broad well-defined arch in the 

 north, the lowest side of which, resting on the dark segment, 

 was particularly well defined. The appearance was, very shortly 

 after this, that of the dark segment breaking through the arch 

 of light in various places, and sending through it dark streams, 

 narrowing as they ascended. The luminous arch was now 

 soon broken up, when there appeared in the N.E. a stream of 

 pale rose-coloured light. The light in the N.W. shortly after 

 assumed the same colour ; and then the light in various inter- 

 mediate places was tinged with the same, that in the N.E. 

 becoming of greater intensity. Distinct pencils of light, stream- 

 ing upwards, appeared now to be propagated from E. to W. ; 

 and brilliant coruscations, tinged with red, proceeded from 

 every part. The phenomena were now nearly the same as at 

 six o'clock, but of very inferior brilliancy. The streams of 

 light gradually faded, and at llh. 20m. the luminous arch, 

 resting upon the dark segment, was formed as before, but the 

 streams of light were very faint. At llh. 45m. the upper side 

 of the luminous arch could be traced ; but the lower side was 

 quite broken, and there were no streams from any part. From 

 lOh. 45m. to llh. 45m. I observed the star Deneb (a Cygni) 

 very distinctly visible through the border of the dark segment, 

 but it was not visible after this. At llh. 20m. this star occupied 

 the highest part of the arc, which must, therefore, have been 

 about 10 in altitude^ and still nearly in the magnetic meridian. 

 The arch, though faint, was visible for some time after mid- 

 night ; and at six this morning, the whole of the northern 

 horizon was illuminated, and I thought the light somewhat 

 tinged, but the moan being up, rendered this doubtful. 



