Mr. cav allots Account of a luminous Appearance, See. 
eclipfed ; but the fides of this luminous arch were more faint 
and tranfparent. 
The inclofed drawing fhews its appearance at about half an 
hour paft ten o’clock. At about three quarters part ten it began 
to lofe its brightnefs, firft at A, and then van iftied gradually, fo 
that at eleven o’clock none of it could be perceived. As icon 
as any part of this arch loft its denfe whiten efs, the ftars ap- 
peared through it quite diftinft, fo that it could not be a cloud. 
The light alfo feemed to vanifti without change of place ; for 
it did not appear to be difperfed through the (ky, or to be driven 
in any dire&ion. 
This extraordinary appearance to me feemed quite diftindt 
from the aurora borealis for the following reafons, viz. becaufe 
it eclipfed the ftars over which it pafled ; becaufe its light, or 
rather its white appearance, was ftationary and not lambent ; 
and becaufe its direction was from eaft to weft. 
The atmofphere was in other refpe&s very ferene, the ftars fhin- 
ing very bright, and no cloud appearing. The northern light 
was exceedingly faint, and very low about the northern point of 
the horizon. The wind was nearly north-eaft, and it could be 
juft perceived in the ftreets. 
I am, &c, 
