IN THE OBSERVATORY OF GREENWICH. 
477 
Detail of the Experiments referred to in this paper. 
Preliminary Experiments to adjust the Slider, and to obtain the reduction to 
a vacuum for portions of air remaining in the Apparatus. — The registered 
arcs must be multiplied by 1.05 throughout, to give the true arcs. 
Slider at 1.5 in. from the middle of the pendulum towards the weight. 
Weight below. 
Exp. A. In full atmospheric pressure. Aug. 21, 1829 a.m. to p.m. Dent making 86465.92 vibr. 
Barom. { endin^ 29 796 } 29781 at57 ° ; + - 019 Ca piU-; —073 to 32° s= 29.727. 
No. of 
Coincid. 
S 
di 
H 
to 
p 
d 
o 
Times of 
Arcs. 
Mean 
Temp. 
Mean 
Interval. 
Mean 
Gauge. 
Correc- 
tion for 
Arc. 
Vibrations 
in 24 hours. 
Disap. 
Reap. 
Coincidence. 
1 
33 
5°6.7 
57-2 
— 
m s 
50 42 
35 57 
m s 
50 58 
36 52 
h m s 
9 50 50 
1 36 24.5 
0.65 
0.13 
| 56.95 
422.95 
— 
O 
+ 0.26 
86057-30 
Exp. B. In full atmospheric pressure. Aug. 21 p.m. Dent making 86465.92 vibrations. 
Barom. |^"^ ng 2 2 ^g 7 3 9 0 6 j 29.813 at 58°; +.019 Capill. ; -.076 to 32° = 29.756. 
1 
2 
3 
25 
26 
27 
O 
57.6 
57.6 
— 
m s 
49 59 
57 02 
04 02 
38 49 
45 51 
52 53 
m s 
50 18 
57 19 
04 22 
39 28 
46 30 
53 54 
h m s 
j. 1 57 10.33 
j. 4 46 10.83 
O 
0.62 
0.18 
O 
| 57.6 
422.52 
— 
O 
+ 0.28 
86056.88 
Exp. C. In ratified air. Aug. 21 p.m. to Aug. 22 a.m. Dent making 86465.92 vibrations. 
1 
2 
3 
4 
122 
123 
124 
125 
O 
57.4 
55.0 
in. 
1.00 
2.90 
m s 
25 53 
33 05 
40 18 
47 30 
01 11 
08 25 
15 40 
22 53 
m s 
26 03 
33 16 
40 30 
47 43 
01 46 
09 05 
16 20 
23 36 
h m s 
j> 5 36 47.25 
]>20 12 22 
O 
1.15 
0.16 
O 
1 56.2 
l + 0.75 
56.95 
434.17 
1.95 
O 
+ 0.68 
86068.26 
