I 2 95 3 
town ; for had the fun-beams fhot from beneath the 
herizoA on fatting rain at a confiderable height above 
the earth, I believe the darknefs would have rendered 
the appearance of fuch a bow far brighter than it 
appears to the fight in the prefence of the fun : but 
this night or evening arch being reflected, as I fup- 
pofe, from particles fo minute as thofe of floating 
vapours, gave but little light and colour to the fight, 
and what would not have been vifible, had the 
fun been above the horizon. For the fame reafon, 
the moon and ftars are vifible in the abfence of the 
fun, and, on the contrary, are unfeen when the fun 
is prefect : and if we light a candle, and fet it in 
the fun-beams, the flame is loft to our fight, tho’ the 
fame candle will give us a confiderable fhare of light 
in the night. As I have never before feen or heard 
of fuch an arch, I thought this account of it (im- 
perfect as it is) might not be difagreeable to the 
Royal Society. 
It could not be a lunar arch, the moon being then 
many degrees below the horizon, and the arch in a 
place, where it could not be affedted by the moon’s 
rays. The confcioufnefs of my inability to give a 
proper account of fuch an uncommon appearance 
could not deter me from the attempt. 
I think I have faid all that is neceflary on this 
fubjeCl ; yet am ready to anfwer any queftion for 
the farther illuftrating of it. I am, 
Reverend Sir, 
Your moft humble Servant, 
College of Phyficians, Lon 
don, June 6th, 1757. 
Geo. Edwards. 
XXXVI. 
