OF A PENDILUM AT GREENWICH AND LONDON. 
93 
The ill accordance of the rates on the 18th — 19th and 19th — 20th, arises 
in a great measure from an indifferent observation of the sun on the 1 9th ; and 
further it appears, that about this time the transit instrument was very un- 
steady, requiring adjustment both with regard to the meridian mark and level. 
These circumstances, combined with the steady going of the clock before 
and since this period, seem to justify the taking —0.54 as a mean rate for the 
whole time; which has been accordingly employed with the following compa- 
risons in the determination of the rate of the clock used in the experiments. 
1828. 
May 15. 
16. 
17* 
18. 
19. 
18. 
19. 
Time by 
Clock, 
h m s 
23 15 0 
23 35 0 
0 31 30 
1 44 30 
1 55 30 
19 34 0 
8 1/0 
Time by 
Transit Clock, 
h m s 
Sidereal 
Interval, 
h m s 
440 ?8 70 }24 23 52 ' 85 
t^o^+^25 0 29.08 
5 42 5/./8i 
6 59 59.51] f. 
7 14 51.20* 24 14 51 69 
0 52 20.31 
13 37 22.10 
Mean 
Interval, 
h m s 
24 19 53.58 
24 56 23.82 
25 12 53.77 
24 10 53.89 
Clock rate 
in 24 hours, 
s 
4-6.34 
4-5.93 
4-5.91 
4-6.05 
1 12 45 1.79 12 42 56./5 + 6.12 
For the subsequent part of the experiments, the following transits have been 
selected from the Greenwich Observations. 
1828. 
June 4. Regulus. . 
(3 Leonis . 
SpicaVirg. 
jj Urs.Maj. 
g Bootis . . 
|3Urs.Min. 
a Cor. Bor. 
June5. Regulus . . 
a Urs.Maj. 
2 a Librae . 
June 7 . Arcturus . 
Observed /R. 
h m s 
aLibrse 
9 59 
11 40 
13 16 
13 41 
14 37 
14 51 
15 27 
9 59 
10 53 
14 41 
14 8 
14 41 
14 41 
35.40 
40.46 
33.10 
8.92 
52.47 
42.00 
48.80 
34.96 
24.47 
47.23 
11.80 
34.88 
46.30 
Apparent /R. 
Error of Clock. 
Means. 
Rate in 
h m s 
s 
24 hours. 
9 59 13.74 
+ 21.661 
11 40 18.82 
+ 21.64 
13 16 11.29 
13 40 47.35 
+ 21.81 
+ 21.57 
at 1 3 h 22 m 
* +21 s .60 
14 37 31.08 
+ 21.39 
14 51 20.42 
+ 21.58 
15 27 27-23 
+ 21.57J 
9 59 13.73 
+ 21.23] 
at ll h 53 m 
> + 2U.21 
s 
10 53 3.33 
+ 21.14 
— 0.42 
14 41 25.96 
+ 21.27 J 
14 7 51.68 
14 41 14.50 
+ 20.12' 
+ 20.38 
at U h 30 m 
> +20 9 .28 
— 0.45 
14 41 25.96 
+ 20.34 J 
Using these rates of the transit clock with the following comparisons of the 
experimental clock, we get its rate. 
Time by 
Time by 
Sidereal 
Interval of 
Clock rate 
Clock. 
Transit Clock. 
Interval. 
Mean Time. 
in 24 hours. 
h m 
S 
h m s h 
m s 
h m s 
s 
June 4. 
20 17 
0 
2 36 48.74 U 
5. 
20 53 
0 
3 16 44.44^ 24 
39 55.70 
= 24 35 53.68 
+ 6.15 
6. 
23 08 
0 
5 27 54.65} 2b 
11 10.21 
= 26 6 53.31 
+ 6.16 
Thomas Glanville Taylor.” 
