made with an invariable pendulum. 
287* 
22 d Aug - . P. M. at Mr. Browne’s. Clock gaining- 0 s , 80. Bar. 29,72. 
Temp. 
Fahren- 
heit. 
Time of co- 
incidence. 
Arc of 
Vibra- 
tion. 
Mean 
Arc. 
Interval in 
Seconds. 
No. of 
Vibra- 
tions. 
Observed 
Vibrations in 
24 hours. 
Correc- 
tion for 
Arc. 
Vibrations in 
24 hours. 
6 ° 6 ,s 
66.2 
66,5 
66.3 
66,7 
66.4 
h, m. s. 
>1 47 7 
3 53 
20 42 
37 32 
54 24 
1 11 19 
28 14 
0 
1,20 
1,09 
0,99 
0,88 
0,80 
°>73 
0,67 
0 
1,14 
1,04 
0,94 
0,84 
0,76 
0,70 
1006 
1009 
1010 
1012 
1015 
1015 
86229,03 
29,54 
29,71 
30,05 
30,56 
30,56 
2,13 
i >77 
M 4 
I » I 5 
0,94 
0,80 
86231,16 
3 M 1 
3 d 5 
3 1,20 
3 M° 
3^36 
66,4 
Mean 
101 1,17 
1009,17 
86229,91 
«>3 7 
86231,28 
RESULTS. 
Date. 
Barometer. 
Thermom. 
Vibrations in 
24 hours. 
Correction 
for Temp. 
Vibrations in 24 
hours at Temp. 
68 degrees. 
August 17 
18 
19 
20 
21 
Observed j 
by Capt. 1 21 
Kater J 
■ 22 
Inches. 
29,86 
29,88 
29,80 
29.83 
29.84 
29.85 
29,72 
6 ° 6,4 
67.1 
68.3 
6 7>5 
66.1 
66.4 
66,4 
86231,38 
86231.22 
86231,03 
86231.23 
86231,45 
86231,32 
86231,28 
— 0,68 
— 0,38 
+ 0,11 
— 0,21 
— 0,80 
— 0,68 
— 0,66 
86230,70 
86230,84 
86231,14 
86231,02 
86230,65 
86230,64 
86230,62 
Mean 
29,83 
66,9 
86230,80 
Correction for Buoyancy . . 
Ditto for Elevation .... 
+ 5>93 
+ ,22 
No. of vibrations of the pendulum in London in Aug. 1 823 
Ditto in May 1820, before the experiments in South'! 
America were made . . ... . J 
86236,95 
86235,98 
Difference between the Experiments of 1820 and 
OO 
°>97 
REMARKS 
As it was not possible that so great a difference could arise from errors of 
observation, it became an object of anxious inquiry to discover the cause. Cap- 
tain Kater was disposed to assign it to an accident which had happened to the 
pendulum at San Bias, but which I, at first, imagined inadequate to such an 
effect. The accident was this : the pendulum, when not in use, was, as usual, 
