RECORD OF AURORAL PHENOMENA. 47 



The colors of the arches, in their general appearance and arrangement, resembled those of the 

 rainbow; but the blue, green, or violet, were not distinctly visible. The yellow ray occupied 

 most space and was the faintest, whilst the orange was the brightest. The red was nearly 

 as abundant as the yellow, and approached in its hue to lake-red. The moon shone brightly all 

 the time. After the disappearance of the Aurora, the sky remained as before, covered with a 

 thin stratum of clouds, but their texture had become more rare, their edges worse defined, and 

 their masses more blended into each other. In short, they answered the description of the 

 cirro-stratus in the first stage of its change from the cirrus. The moon had a bur or halo round 

 it; and a candle, both in the open air and the house, was also surrounded by a halo. 



At lib. 30m., there was a faint mass of light in the S. S. W., about 20° high, occasionally fading 

 away, and allowing a body of dark cloud to appear in its site. The light reappeared first in 

 the centre of the cloud of a gold-yellow color, but became fainter as it spread outwards. 



At midnight, the weather was rather hazy, and there was very little blue sky to be seen. A few 

 minutes before twelve, a portion of cloud in the S. E. was faintly illuminated ; and, at the same 

 instant, a luminous spot made its appearance in a clear blue space in the north, about 15° high. 

 From this spot, an arch shot up which, passing to the eastward of the zenith, joined the luminous 

 cloud in the S. E. The arch was scarcely formed when it disappeared, but was as speedily 

 formed again by a mass of light rising in the S. E., and rolling to the north like a volume of 

 smoke from a chimney, increasing in dimensions as it rose. Immediately after the second forma- 

 tion of this arch, it assumed that appearance of a shoot of the moss alluded to in the notes on 

 November 24th, and which is termed by botanists falcalo-secund. The points of the rays or 

 streams were directed to the south. In a short time, the arch separated into small curved seg- 

 ments, which vanished in their turn; and the attention was next directed to the formation of a 

 long range of prismatic light about 60° high, its extremes bearing west and north. This 

 light had a pale gold-yellow color, and was attenuated towards the north, its southern or upper 

 edge being brightest. When this passed away, a number of irregular masses appeared in various 

 parts of the sky. At lh. a. m. (21st), the sky was obscured by a fog." — Ibid., p. 612. 



December 21, 1820. Temp. —42°. 



"During the early part of the evening, there were a few thin horizontal clouds in the N. E., but 

 the sky in general had a clear grayish-blue color. Some streaks of cirrus were faintly visible ill 

 the east. The moon shone brightly, but was surrounded by a bur, as was also the caudle. 

 Rapid noisy. 

 At lOh. 20m., the Aurora rose in the S. S. E., and, proceeding across the sky, divided into several 

 broad arches, which terminated about 30 c from the western horizon. The common stem in the 

 S. S. E. appeared as if formed by the twisting of the ends of the different arches together, and 

 had a waving irregular motion, sometimes apparently doubling upon itself; and once or twice it 

 separated into small parallel portions, haviug a lateral motion in the direction of the arch, but 

 with their ends pointing north and south. The arches were three, and at one time four, in 

 number, and gradually diverged more and more from each other towards their western ends. 

 The uppermost passed a little to the southward of the zenith, and they were each about 4° or 5° 

 broad. The spaces between them were sometimes faintly illuminated. After they had continued 

 stationary for about ten minutes, the S. S. E. common stem moved slowly round the horizon 

 until it bore south, leaving a streak of light behind it, whilst the truncated ends, or those which 

 were directed towards the western horizon, approached each other, and were lengthened out to 

 the horizon in the W. N. W. by the rolling motion of smoke. Contemporaneously with these 

 motions, the centre of the arch moved up and down, so as to appear undulated and even con- 

 torted; the moving parts frequently dilating considerably, and always becoming brighter in the 

 centre, at the commencement of their motion. The light had a pale yellow hue, and, when 

 brightest, was not sufficiently dense to hide the larger stars. Its motions were in general slow, 

 and unattended by flashes. 

 At llh., a bright arch extended across the zenith from E. by S. to N. W. by W. ; the S. W. quarter 

 of the sky being at the time occupied by a homogeneous mass of light, which had a crescentic 

 edge turned towards the east, and there was a similar mass in the north concave towards the 



