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But what appears moft fingular, in this phenomenon is, that 
in Dublin the corona was manifeftly prifmatic, but in the clear 
air of the Obfervatory it was a vivid white. It continued vifi- 
ble, though gradually decaying, for thirty-five minutes from the 
time I firft faw it, and was at length obfcured by ragged clouds 
from the W. S. W. from which point the wind came, and where 
there appeared a vaft accumulation of vapour. I could plainly fee 
that thefe clouds were far below the feat of the parhelia; the whole 
was fucceeded by a tempeftuous night. The barometer had 
been rifing, but immediately began to fall to the amount of 
eight-tenths of an inch in the courfe of the night. 
As to the elliptic figure of the corona, it is remarked by 
Opinus that in high latitudes they are more elliptical than in 
low ones. 
