260 
zon, but from points having an altitude of about 40°; and 
they very frequently extended upwards to their point of 
intersection, producing there a light of considerable inten- 
sity. The illuminated sector of the sky, supposing it pro- 
longed to the horizon, subtended an angle of about 30°. 
The most remarkable circumstance connected with this 
aurora was the following. About nine o'clock, it began 
to move slowly round, taking an easterly direction; and 
when, in the course of fifteen or twenty minutes, it attained 
a north-westerly bearing, the sky was lighted up on every 
side with singular brilliancy. The appearance’ which now 
presented itself, is best conveyed by stating, that it was pre- 
cisely such as would be produced by the extension, at the 
same instant, of the aurora already described, through every 
point ofazimuth. This magnificent illumination lasted only 
about a minute, but left behind it, very nearly due west, a 
fasciculus of beams quite similar to those which first attracted 
attention. 
The night was remarkably fine and still, having been 
preceded by a day of unusual warmth and sunshine. The 
sky was not destitute of clouds, but they had a considera- 
ble elevation, were small and scattered, and were penetrated 
by the light of the stars, which were visible in considerable 
numbers. 
Mr. George Downes read extracts of a second letter 
from Professor Rafn, Secretary to the Royal Society of 
Northern Antiquaries of Copenhagen. In this letter Pro- 
fessor Rafn suggested that, as his researches relative to Ame- 
rica appeared to be, as yet, but little known in Ireland, it 
might perhaps be advisable, that his ‘“ Memoir on the Dis- 
covery of America in the tenth Century,” already published 
at Copenhagen in the Antiquitates Americane, should be 
reprinted in the Transactions of the Academy, with an in- 
troduction, which he proposed to furnish, and with some ad- 
