OF THE VIBRATIONS OF AN INVARIABLE PENDULUM. 
213 
Therm. 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 
32 
33 
34 
35 
36 
37 
38 
39 
70.8 
71.1 
71.5 
71.6 
71.8 
72.0 
72.3 
72.5 
”72.6 
Gauge. 
Times of 
Disapp. 
Re-app. 
Coincidence. 
inch. 
m s 
m s 
h m s 
7.00 
7 54 
8 00 
1 07 57 
7.56 
14 10 
14 18 
1 14 14 
7.10 
20 27 
20 34 
1 20 30.5 
8.00 
26 44 
26 50 
1 26 47 
7.00 
33 00 
33 06 
1 33 03 
8.10 
39 16 
39 24 
1 39 20 
7.00 
45 33 
45 41 
1 45 37 
8.00 
51 50 
51 58 
1 51 54 
6.70 
58 06 
58 14 
1 58 10 
7.90 
4 24 
4 32 
2 04 28 
5.60 
10 40 
10 50 
2 10 45 
7.00 
16 58 
17 08 
2 17 03 
7.00 
23 16 
23 26 
2 23 21 
7.00 
29 34 
29 43 
2 29 38.5 
7.00 
35 51 
36 01 
2 35 56 
7.00 
42 08 
42 19 
2 42 13.5 
7.10 
48 26 
48 36 
2 48 31 
7.10 
7.10 
7.00 
6.90 
54 44 
54 56 
2 54 50 
7 20 
7 31 
3 07 25.5 
6.90 
6.90 
19 57 
20 07 
3 20 02 
6.90 
6.90 
32 33 
32 44 
3 32 38.5 
7.10 
7.50 
6.90 
7.00 
7.00 
45 10 
45 21 
3 45 15.5 
57 47 
57 59 
3 57 53 
10 24 
10 36 
4 10 30 
7.00 
6.90 
16 42 
16 56 
4 16 49 
7.00 
29 18 
29 33 
4 29 25.5 
7-00 
35 37 
35 52 
4 35 44.5 
6.90 
7.00 
7.00 
7.00 
7-00 
41 56 
42 11 
4 42 03.5 
54 33 
54 49 
4 54 41 
7 11 
7 25 
5 07 18 
7.08 
Inter- 
vals. 
377 
376.5 
376.5 
376 
377 
377 
377 
376 
378 
377 
378 
378 
377.5 
377-5 
377.5 
377.5 
379 
377.5 
378 
378 
378.5 
378 
378.5 
378.5 
378.5 
378.5 
379 
378.5 
378.5 
379 
378 
378.5 
379 
379 
378.5 
379 
578.5 
378.5 
Arc register- 
ed and True 
Arc. 
/ o / 
00 = 1 42 
1 50 
1 43 
1 28 
1 14 = 1 03 
1 03 
0 52 
0 44 = 0 37 
Mean 
Interval. 
>377.29 
>378.55 
Correc- 
tion for 
Arc. 
+ 3.03 
+ 1.11 
Temp. 
correct- 
ed. 
72.06 
72.94 
s 
+ 0.02 
+ 0.40 
Corrected 
vibrations 
at 72°. 
85944.85 
85944.85 
85944.85 
On re-admitting the air, the thermometer rose from 72°.6 to 7 3°.8, and then 
gradually fell until it took up the temperature of the apartment, which was 
rather less than 7 3°.5. After the lapse of half an hour, the following observa- 
tions were commenced, the glasses remaining on, but a free communication 
existing with the external air through the exhausting pipe. 
