RECORD OF AURORAL THE NO MENA. 49 



December 23, 1820. Temp. —45°. 



"At llh. p. m., a faint arch of pale greenish light, about 10° broad, rose to the height of 30°. One 

 of its limbs, bearing S. E. by S., sprung from a collection of whitish clouds (cirri) situated 

 about 10° above the horizon. The other, bearing W. by N , faded away imperceptibly in a 

 dark part of the sky, where there were neither clouds nor stars visible. 



The moon was surrounded by a bur, and did not give much light. 



At 12h., the arch was still visible, but several strata of pretty dense white clouds now occupied 

 the sotithern part of the slcy to the height of 20°, and the extremities of the arch, which were 

 broader and fainter than before, bore S. by E. and W. N. W. 



In the middle of the arch, there were several gentle elevations and depressions; but, although the 

 light occasionally brightened up in some spots, there were no quick motions amongst its parts. 



The state of the atmosphere continued, as before, pretty clear in the zenith; but the bur round 

 the moon, of a faint gray color, with a slight tinge of orange on its outer edge, remained. A 

 similar bur was formed round a candle, its diameter enlarging rapidly as the observer receded 

 from it."— Ibid., p. 617. 



December 25, 1820. Temp. —28°. 



"At lh. a. m. (26th), the Aurora appeared for the first time this night, in form of a faint arch, 

 extending from the altitude of 40° in the N. W. to a spot near the zenith, bearing S. E. 

 It was composed of longitudinal bands or streams of light, connected with each other by a faint 



luminousncss. 

 A little snow was falling at this time in minute crystals, and there was a slight haziness in the 

 sky."— Ibid., p. 618. 



December 26, 1820. Temp. —32°. 



"At lOh. 30m., an arch-formed Aurora, about 8° broad, appeared a little to the southward of the 

 zenith. Its extremities descended to within 15° of the horizon, and terminated in the S. E. 

 and N. W. At one time, the light of the arch appeared of uniform density throughout; at 

 other times, it was most intense along its southern or lower edge, and became gradually fainter 

 upwards until it disappeared. 



The stars were seen obscurely through the denser light; in other parts of the sky they shone 

 brightly. At the same time, there appeared in the E. S. E., parallel to the horizon, a mass of 

 bright light with two or three dark horizontal streaks across its face, produced apparently by 

 intervening layers of cloud. The arch continued for a considerable time without undergoing 

 any material alteration in its appearance, except that it occasionally brightened up and faded 

 away again. Once, indeed, for a few moments, it separated into portions parallel to each other, 

 but having about 11° of obliquity with respect to the arch. These portions emitted a bright 

 light, and were separated by faintly luminous spaces. 



At llh., the arch, having nearly the same direction as before, was composed throughout the greater 

 part of its length by two parallel portions, each gradually fading away towards their edges ; 

 and the S. E. end of the arch was also lengthened out and bent towards the east, so as to come 

 in contact with the mass of light noticed above as bearing E. S. E. This bent portion of the 

 arch was composed of several bars nearly of equal length, and arranged so that every succeeding 

 one lay to the north of that which preceded it in their approach to the horizon. The whole 

 were connected together by a faint diffused light; and from the same body of light in which that 

 end of the arch now terminated, a column of faint beams rose perpendicularly to the height of 15°. 



At llh. 20m., the arch had increased its breadth to 20°, its northern edge being very near the 

 zenith. Its extremities, bearing S. E. and N". W., were composed of irregular and somewhat 

 detached roundish masses, but its centre consisted of five bright longitudinal bands, connected 

 by a faint diffused light. The mass of light formerly bearing E. S. E. had now moved round 

 towards the south, and, still resting in the horizon, formed the S. E. end of the arch. 



At midnight, a great number of detached masses of light occupied the sky from 20° south to 10° 

 north of the zenith. These masses of light varied in shape, but the greater number had some- 

 what of an oblong form. They were separated in some-places by clear blue sky, in others they 



