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degrees ; and from that day to the prefent it hath 
always been lefs j which is the principal reafon why 
it was invifible to us at the time when it was in its 
perihelion, and hath remained fo ever fince. The 
elongation will indeed foon become greater, and yet 
it is probable that we fhall not be able to fee the 
Comet again ; becaufe its real diftance from the fun 
will be greater than it was when I firft faw it, and it 
will be alfo four times further from us than it was 
at that time. 
The Comet kept nearly at the fame diftance from 
the earth for ten or twelve days together after I firft 
faw it ; but its brightnefs gradually increafed then, 
becaufe it was going nearer to the fun. Afterwards, 
when its diftance from the earth increafed, altho’ it 
continued to approach the fun, yet its luftre never 
much exceeded that of ftars of the fecond magni- 
tude, and the tail was l'carce to be difcerned by the 
naked eye. 
All the forementioned obfervations were made with 
a Micrometer in a feven-foot Tube, excepting thofe 
of the 3d, nth, and 17th days of Odtober, which 
were taken with a curious Sedtor conftrudted for fuch 
purpofes by the late ingenious Mr. George Graham ; 
of which Dr. Smith has given a very exadt defcrip- 
tion in his third book of Optics. 
Suppofing the Trajedtory of this Comet to be pa- 
rabolic, I collected from the foregoing obfervations, 
that its motion round the fun is dir eft , and that it 
was in its perihelion Odtober the 21ft, at 7 11 yy' mean 
(or equated) time at Greenwich. That the inclina- 
tion of the plane of its Trajedtory to the ecliptic is 
12 0 50' 20" y the place of the defcending Node » 4 0 
