in the length of the pendulum vibrating seconds. 
399 
Clifton, 6th October, 1 8 1 8 . Barometer 29,20 inches, thermometer 42 0 , chrono- 
meter too fast i 5 ,o. Pole star on the meridian by the chronometer 1 i h .56 m .56*,7. 
Chronometer. 
Level. 
Time from 
the 
meridian. 
N. v. Sines. 
h. m. s. 
m. s. 
* 1-33.50 
+ 
30 
— 21 
23. 7 
5 o8 3 
11.38.33 
+ 
24 
— 29 
18.24 
3221 
11.41.25 
+ 
4 
— 53 
! 5-32 
2296 
1 1.44.25 
43 
— 12 
12.32 
1495 
11.46.53 
+ 
17 
— 39 
10. 4 
0964 
11.50 15 
+ 
4 * 
— i 5 
6.42 
0427 
1 I - 53 - 5 
+ 
24 
— 3 ° 
3 - 5 z 
0142 
n. 56. 25 
+ 
37 
— 19 
0.32 
0003 
11.59.23 
+ 
30 
— 25 
2.26 
0056 
12. 1.55 
+ 
32 
— 25 
4.58 
0235 
12. 5.25 
+ 
3 6 
— 1 8 
8.28 
0682 
12. 8. 5 
+ 
27 
— 3 ° 
11. 8 
1180 
12. 1 1. 15 
+ 
•4 
— 44 
14 18 
1946 
12.14.43 
+ 
4 1 
— 15 
17 46 
3003 
12.17.25 
+ 
26 
— 3 ° 
20.28 
39 8 5 
12.21. 0 
+ 
40 
— 17 
2 4 - 3 
55°! 
Mean - 
4-466 
— 422 
1888 
Readings, &c. 
U-466-4 M) x ^ = + s " >8 cor . for , he l5vel . 
Const. Log. 
Log. 1888 (-(-4) 
Correct. — 1 1^,80 Log. 
3.7959304 
- 7.2760020 
1.0719324 
1st Vernier 
0 / // 
I 97 i 55-5° 
Second 
25 
Third 
- 20 
Fourth 
50 
Mean 
- 197-55-36,25 
Level 
4- 360. 0. 0 
- 4- 52,80 
Index 
- + 18,00 
Observed Z. D. 
16) 557.56.47,05 
34.52.17,94 
Refract. 
- + 4°>3 I 
Correct. 
- — 11,80 
2 r'C. 
- — 0,06 
(Z-ZO 
1 
+ 
0 
O 
True Z. D. 
- 34-5 2 -4 6 > 6 9 
Mean P. D. for 1818 + 1.39.44,15 
Precession, &c. 
- — i3>5 6 
Co. 
Lat. 36.32.17,28 
Lat. of Clifton 
- 53- 2 7-42.72 
On comparing the three preceding results, a difference may 
be perceived between them amounting to 5 ", 2^', and as I 
felt assured that the principle of the repeating circle was too 
perfect to allow of an error of this magnitude, a little reflec- 
tion led me to discover the cause, to be my fancied improve- 
ment in fixing the level to the pillar of the instrument. For 
in turning the telescope on its axis, the friction, however slight 
it may be, tends to disturb the relative position of the circle 
