310 Professor Farrar’s observations of the Comet of 1811. 
to make use of these stars, till Arcturus got so near the horizon, as to 
be subject to a very great refraction. I then employed the Pole Star 
instead of it, and afterwards Atair, the motion of the comet being direct- 
ed nearly toward this star. I took the distances also of several other 
stars, as a check, some of which I have here given. There is some 
uncertainty in the first observations, on account of the irregularity of . 
the refraction, the comet being very near the horizon, as also with re- 
ard to the last on account of its faintness, 
The following distances are the means of from four to ten obser- 
vations. They were taken with a good sextant, divided to half min- 
utes, the times being carefully noted by means of a watch provided 
with a second hand. The watch was compared before and after the 
observations of each evening with a well regulated clock, and seldom 
found to vary more than 1” or 2” during the interval employed in ob- 
serving. | 
Arcturus. . Lyra. 
7 32 16 
App. times. App. dist. App. times. App dist. 
a," cgiog ye are ia 
Sept. 6 7 52 14 47 43 20 8 03 14 82 11 00 
7 8 35 30 46 48 00 8 20 30 81 15 00 
8 8 38 26 46 28 00 8 24.16 80 23 00 
97 5920 45 38 20 7 54 40 79 32 18 
10 819 38 44 53 16 747 31 78 30 46 
13 8 3225 42 45 22 8 26 58 75 36 37 
14838 18 42 00 15 8 28 20. 74 33 50 
167 5719 40 28 30 7 46 49 72 29 00 
17 8 28 00 29 50 00 8 912 71 23 20 
18 7 39 23 38 58 00 7 27 02 70 18 50 
20 8 03 00 36 43 00 8 00 6O 66 44 51 
24.7 42 33 34 33 30 7 40 55 62 56 16 
267 26°41 © $3 08 15 60 17 10 
