No. III.] 



Dr. RICHARDSON ON THE AURORA. 



611 



appeared pretty dense in the bright moonlight, were yet rare enough to allow 

 the larger stars to appear through them. 



By one o'clock, the whole mass of cloud had gathered together towards the 

 south, and disappeared in the horizon ; but at the same time a few long and 

 very rare threads of cloud, which were at intervals faintly luminous, shot 

 athwart from east to west in the deep blue of the northern part of the sky. 

 On former occasions, the Aurora had been observed to illuminate the face of 

 the clouds next the earth ; but the present night was remarkably favourable 

 for the observance of that phenomenon, the brightness of the moon-light, and 

 the clearness of the sky, rendering the clouds very visible and well defined. 



December 19th, 1820. 



Hour. Temp. Wind. 



A. M. 9 - 42 W. Moderate. Clouds of cirro-stratus. Thick mist over 



the Rapid, which was rather silent. 

 Noon -41 W.S.W. do. Cloudy, sun obscured. 

 P. M. 9 -38 N.b.S. do. do. Halo round the moon at the 



distance of 12°. 



Midnt. - 38 W. do. Rather hazy, large stars only visible ; Rapid 



inaudible. 



At midnight the sky cleared up, a few cirro-strati were seen to the south- 

 ward, and there was a slight bur round the moon ; the rest of the sky was of 

 a grayish blue colour. At this time a broad bank of the Aurora appeared in 

 the north, lying horizontally, at an elevation of 25°. There were also a few 

 long parallel streamers to the westward, flashing in the direction of their 

 lengths, from W. b. N. to E. b. S. They disappeared suddenly, leaving in 

 their site a faint yellowish light. 



December 20th, 1820. 



Hour. Temp. Wind. 



A.M. 9 -43 S. Light. Foggy. 



10 44 do. do. do. f A very dense mist rising from the 



Noon -41 S.W. do. Clear, bright sun J ™ A "^"T T ^ 



° J river and m the low valley. Rapid 



P.M. 9 -46 E.N.E. do. Very clear. I very loud in the evening. 



10f -46.6 E.N.E. Calm. do. 

 Midnt. -45.6 E.N.E. do. Slight haze. do. 

 A. M. 1 — E. Light. Foggy. Rapid continuing noisy. 



4 i 2 



