160 
REV. F. FALLOWS’S OBSERVATIONS WITH AN INVARIABLE 
Appendix. 
Observations made by Captain Ronald with the invariable pendulum (No. 4. 
of Sabine), in Portland Place, London. Lat. 51° 31' 8".4. 
1825. 
Barom. 
Therm. 
No. of 
Coin. 
Disapp. 
Re-app. 
Time of Coin- 
cidence. 
Arc. 
inches. 
m s 
m s 
h m s 
July 31 l 
29-950 
70.48 
1 
31 21 
31 28 
1 31 24.5 
1.1 85 
29-934 
70.50 
11 
28 03 
28 18 
3 28 10.5 
.610 
29-944 
69-75 
1 
13 35 
13 45 
11 13 40.0 
1.110 
Aug. 1 < 
29-942 
70.25 
11 
10 34 
10 49 
1 10 41.5 
.575 
29-942 
70.35 
1 
33 55 
34 01 
1 33 58.0 
1.320 
29.941 
70.65 
11 
30 31 
30 45 
3 30 38.0 
.670 
9 J 
29.950 
71-00 
1 
49 29 
49 36 
10 49 32.5 
1.225 
2 i 
1 
29.944 
71-90 
11 
45 59 
46 15 
0 46 7.0 
.640 
r 
29.944 
71-90 
1 
58 01 
58 08 
0 58 4.5 
1.305 
L 
29-944 
71-80 
11 
54 26 
54 41 
2 54 33.5 
.665 
o i 
r 
29.952 
71-00 
1 
9 39 
9 44 
11 9 41.5 
1.370 
3 1 
L 
29-952 
71-80 
11 
6 02 
6 14 
1 6 8.0 
.695 
r 
29-953 
71.80 
1 
18 47 
18 55 
1 18 51.0 
1.180 
» 
29-924 
72.00 
11 
15 16 
15 29 
3 15 22.5 
.605 
r 
29-584 
72.20 
1 
52 51 
52 57 
0 52 54.0 
1.310 
29.574 
72.00 
11 
49 11 
49 24 
2 49 17.5 
.665 
c 
\ 
29-500 
70.30 
1 
33 38 
33 44 
10 33 41.0 
1.290 
0, 
! 
29-520 
70.75 
11 
30 18 
30 30 
0 30 24.0 
.640 
r 
29-522 
70.80 
1 
36 24 
36 31 
0 36 27.5 
1.370 
» 
29-530 
71.05 
11 
32 51 
33 03 
2 33 57.0 
.685 
c 
f 
29-628 
67.20 
1 
46 11 
46 16 
11 46 13.5 
1.315 
0 
29.616 
68.60 
11 
43 21 
43 34 
1 43 27.5 
.650 
Mean. . 
29-804 
Observations computed. 
Observations. 
Mean Temp. 
Interval. 
Vib ns in 24 Mean 
Solar Hours. 
Corr. for 
Arc. 
Rcduct. to 
70° 82 'Fahr. 
Reduced Vib ns in 24 
Mean Solar Hours 
at 62° Faiir. 
1 
70.49 
h m s 
1 56 46.0 
86153.354 
+ 1-277 
-0.139 
86154.492 
2 
70.00 
1 57 01.5 
86153.899 
1.124 
0.345 
86154.678 
3 
70.50 
1 56 40.0 
86153.143 
1.568 
0.135 
86154.576 
4 
71.45 
1 56 34.5 
86152.949 
1.378 
+ 0.265 
86154.592 
5 
71.85 
1 56 29.0 
86152.754 
1.534 
0.434 
86154.722 
6 
71.40 
1 56 26.5 
86152.666 
1.685 
0.244 
86154.595 
7 
71.90 
1 56 31.5 
86152.843 
1.260 
0.455 
86154.558 
8 
72.10 
1 56 23.5 
86152.560 
1.541 
0.539 
86154.640 
9 
70.52 
1 56 43.0 
86153.249 
1.467 
-0.126 
86154.590 
10 
70.92 
1 56 29.5 
86152.772 
1.665 
+ 0.042 
86154.479 
11 
67-90 
1 57 14.0 
86154.336 
+ 1.521 
— 1.229 
86154.629 
Mean = 
70.82 
Correction for rate 
Correction for buoyancy .... 
Reduction to 62° Fa hr 
86154.595 
+ 0.441 
+ 5.873 
+ 3.713 
86164.622* 
* Note. — 'I he accordance of this result with that obtained by Captain Sabine, is sufficient to show 
that the instrument remained unaltered, and warrants the comparison of any future observations with 
tlio obtained by former observers ; subject, of course, to any change, which it may have undergone 
since that period, or that it may yet meet with, which can only be satisfactorily ascertained, when 
another scries shall have been made with it, in London, where its rate is probably better known, than 
at any other of Captain Sabine's stations. 
