fome luminous Arches* 3 5 
i 
for half an hour ; and although I could not difcover any coruf- 
cations, or quick motion, In any part, yet the different por- 
tions of it were perpetually varying in the denfity of their 
light, and the whole arch, or at leaft its vertex, made a flow 
and equable motion towards the fouth. Where the light was 
the mod denfe, the fmaller ftars were rendered invifibl^ by the 
arch, but ftars of the fecond magnitude were not totally 
eclipfed by it. This arch difappeared, as the former, by 
patches ; the light gradually becoming lefs intenfe. The 
colour of both thefe arches was white. 
Before the latter arch had intirely difappeared, a fmall one, 
not quite fo broad as the rainbow, arofe from its eaftern leg, 
and afcending in a curvilineal diredtion to the polar ftar, ter- 
minated there. Its light was more faint than that of the 
other two arches. It continued vifible about a quarter of an 
hour. 
When I ufe the terms afcending and defending , I would not 
be underftood to mean, that the appearance of thefe arches 
was progrejfive from eaft to weft : they were all completely 
formed when I firft difcovered them ; even the fmall and im~ 
perfedt arch laft mentioned, which appeared while I was exa- 
mining the larger one, had no progreffive motion. I firft faw 
it complete, though a few minutes before there was nothing 
luminous where it appeared. 
The evening was very fine when I faw thefe beautiful phe- 
nomena ; the ftars were bright, and there was not a cloud to 
be feen except in the horizon. There was a fteady light in 
trie north, without the leaft corufcation, extending from the 
N.B. to N.W. The wind blew from the N.E. 
On the 26th of March, about the fame time in the evening, 
I was entertained with a fimilar appearance, as I was travelling 
F 2 
m 
