ns of the comet of 1807. 
servation of this kind, that we made, which will be given at the end 
of this memoir. 
The apparent motion of the comet was “ahoeaeing in a tas “es at 
the average rate of about a degree per day. _ It passed in succession 
through the constellations Mons Menalus, Serpens, Hercules, Lyra, 
Cygnus, and Lacerta, and.on the thirtieth day of January 1808 was 
_ near the extremity of the right hand of 4ndromeda. It had then the 
appearance of a Nebula, and was so faint, as to be hardly visible 
with the assistance of the night-glass._ After this time I was prevent- 
ed by indisposition from. seeking for it. 
In reducing the observations, made with the circular instrument, 
allowance was made for the warentions ea the distances. during the 
time elapsed between observir diflcrent stars, so as. to make 
the distances eae to ‘ist same eee -This’e 
tion Baas small was calculated with sufficient accuracy by sacar a 
Proportional ‘part of the observed daily imcrease or decrease of dis- 
tance. - iaceiens was made for refraction by adding to the observ- 
ed distances a small correction, calculated by Shepherd’s’ “ Tudles 
“for correcting the apparent distance of the Moon and Stars, ete.” 
by taking twenty times the correction in the column “ Var,? corres. 
ponding to the observed distances and altitudes ;* this being the yal- 
uc for the mean temperature and density of the air. The Parallax 
was so small, that it was neglected. The Aberration, which some- 
times exceeded a minute, was found and applied to the calculated 
longitudes and Jatitudes made use of in the last process for finding 
the elements of the orbit. _ The longitudes were always counted 
* This tabular correction is equal to the variation of the apparent distance of ati two hea- : 
Perieneten <yrsnntnvae re ee me gispigcarc ee and is 
nearly t th 
Dessay jee ik faiecescd te oe deacon tee 
