(seq. 1)

Cambridge 8 {February} 1784

Dear Sir:

I thank you for your attention to Phil. Trans.
Have the Memoirs of the {French} {Academy} of Sciences arrived & how late?

Your Salem Gazette is the only one which furnishes
either Observations or Ramarks on the Comet. I was in hopes
that many bservations would have been made; but am sorry
to find it otherwise. I got four & had not the moon been in the
way should have had more. As it is we must rest satis-
fied till we see whether it appears again in the east, a little
before sunrise. I suppose it passed its Perihelion about the
fourth of this Month, & was on its descent when we saw it.
If this idea is well founded we may expect to see it on its
retreat in the eastern gemisphere, unless the distance
from the earth should be too great before it emerges from
the twilight.

I have endeavored to ascertain its Elements, as well as I
can, graphically; for it is too much trouble & takes too much
time to go through the Calculations. The method of exhibiting
its trajectory is described by Delalande LIV {Livre} XIX. of his Astronomy
in familiar language. Of three parabolas, I think it that were
tried, I think that answers best which was projected for the same
perihelion distance as that of the Comet in 1661; But some of the
Elements seen in this methid (tho' it is but a coarse one) to differ
too much. Yet the differences are not greater that [?] than in
some calculations that have been oade of the same Comet;
witness two calculations of that in 1264, that in 1337, that of 1596;
& one which Delalande has supposed to be the same in 1698 & 1699,
but has made two entries for it on account of the differences.
That there should be diffferences in calculations of the same Comet at the same