74 RECORD OF AURORAL PHENOMENA. 



of a ribbon. As the light proceeded along the arch, coruscations emanated from it; and, as the 

 motion became violent, the curve was often deflected and sometimes broken into segments, which 

 were brightest at their extremities and in general highly colored. When one ray of the Aurora 

 crossed another, the point of intersection was sometimes marked by a prismatic spot, very similar 

 to that which oecurs in the intersections of corona? about the moon, but far more brilliant; 

 and when the segments, which generally crooked towards the zenith, were much curved, colors 

 were perceptible in the bend. Generally speaking, after any brilliant display, the sky became 

 overcast with a dense haze or with light fleecy clouds. 



The Aurora has been frequently observed to rest upon a dark nebulous substance, which some 

 persons have supposed to be merely an optical deception, occasioned by the lustre of the arch; 

 but this appearance never occurs above the arch, which would be the case, I think, if these 

 surmises were well founded. We sometimes saw this cloud before any light was visible, and 

 observed it afterwards become illuminated at its upper surface, and exhibit all the appearances 

 above mentioned. 



It was the general opinion that the lustre of all the stars was diminished by the Aurora, but par- 

 ticularly by this part of it. 



Captain Parry, however, observes that the stars in this dark cloud were unobscured, except by the 

 light of the Aurora. He, however, agrees with us in the lower part of the arch being always 

 well defined, and the upper being softened off, and gradually mingled with the azure of the sky. 

 It is worthy of notice, that we never observed any rays shoot downwards from this arch, and I 

 believe the remark will apply equally to the observations of Captains Parry and Franklin." — 

 2Beechey, 2, 722. 



N. P. — 1. In 1826, Aurora generally began in the W. N. W. and passed over to the N. E. 



2. After a certain period, it as regularly began in the N. E. and passed over to N. W. 



3. Whilst in 1827 the appearance of it was uncertain. 



4. It was, however, uniform in making its appearance always in the northern hemisphere. 



5. It was frequently observed to rest upon a dark nebulous cloud. 

 G. We sometimes saw the cloud before any light was visible. 



7. The lustre of all the stars was diminished by the Aurora. 



"We frequently observed the Aurora attended by a thin, fleecy, cloud-like substance, which, if not 

 part of the meteor, furnishes a proof of the displays having taken place within the region of 

 our atmosphere, as the light was decidedly seen between it and the earth. This was particu- 

 larly noticed on the 28th of September, 1827. The Aurora on that night began by forming two 

 arches from W. by N. northward to E. by N., and about eleven o'clock threw out brilliant 

 coruscations. Shortly after, the zenith was obscured by a lucid haze, which soon condensed 

 into a canopy of light clouds. We could detect the Aurora above this canopy by several bright 

 arches being refracted, and by brilliant colors being apparent in the interstices. 



Shortly afterwards the meteor descended, and exhibited a splendid appearance, without any inter- 

 ruption from clouds, and then retired, leaving the fleecy stratum only visible as at first. This 

 occurred several times, and left no doubt in my own mind of the Aurora being at one time above 

 and at another below the canopy formed about our zenith. 



I must not omit to observe here that, on several occasions when the light thus intervened between 

 the earth and the cloud, brilliant meteors were precipitated obliquely toward the south and 

 southwest horizons." — Ibid., p. 723. 



N. B. — 1. Aurora frequently attended by a fleecy cloud-like substance; 



2. Which proves that its displays were within the region of our atmosphere, 



3. As the light was decidedly between it and the earth. 



4. Aurora at one time above and at another time below a canopy formed about our zenith. 



5. On several occasions, when the light intervened between the earth and the clouds, 



brilliant meteors were precipitated. 



"This supposition of the light being at no great elevation, is strengthened by the different appear- 

 ances exhibited by the Aurora at the same times to observers not more than from ten to thirty 

 miles apart, and also by its being visible to persons on board the ship at Chamisso Island after it 



