486 CAPTAIN SABINE ON THE LENGTH OF THE SECONDS PENDULUM 
the day, with observations of coincidences before and after, it will be advisable 
to take the mean of these daily rates as above for the rate to be employed 
throughout on any one day, rather than employ the former for coincidences 
observed in the morning, and the latter for afternoon coincidences. 
(Signed) Thomas Glanville Taylor. 
Experiments with Captain Rater’s Pendulum on the fixed iron frame on the 
south wall of the Pendulum Room at the Royal Observatory. The agate 
planes the same which had been used in the vacuum apparatus. The same 
thermometer also, and arc. Barometer, the standard of the Observatory. 
Slider at 1 .6. Weight below. Clock by Graham ; its rate furnished by Mr. 
Thomas Glanville Taylor in the subjoined memorandum. The correction 
for the arcs computed by the usual formula, and multiplied by 1.13. (p. 469.) 
Exp. H H. September 30. Graham making 86520.71 vibrations. 
Barom. jg ^ 30.1 13 5 +.019 Capill.j -.058 to 32° =30.074. 
No. of 
Coincid. 
Therm. 
Disap. 
Tii 
Reap. 
nes of 
Coincidence. 
Arcs of Vibration. 
Mean 
Temp. 
Mean 
Interval. 
Correc- 
tion for 
Arc. 
Reduc" 
to mean 
temp.53° 
Reduc- 
tion to a 
vacuum. 
Vibrations 
in vacuo 
at 53°. 
1 
2 
3 
30 
31 
32 
O 
49-65 
51.35 
m s 
3 33 
9 47 
16 00 
4 49 
— 
17 20 
tr> s 
3 43 
9 58 
16 13 
5 16 
.... 
17 48 
h m s 
j>ll 09 52.3 
2 11 18.2 
0.80 x 1.05 = 0.84 
0.19x1.05 = 0.20 
1” 
>50.5 
l 
J 
375.38 
+ 6.43 
-1.10 
+ 12.30 
86071.35 
Exp. I I. Fresh impulse. Barom. 30 j 44 5 1 *‘25 
\ 30.131 ; +.019 Capill.;— .058 to 32°=30.092. 
1 
24 
O 
51.3 
50.9 
m s 
35 47 
59 24 
m s 
35 56 
59 50 
h m s 
2 35 51.5 
4 59 37 
6.80X1.05 = 0.84 
0.28X1.05 = 0.29 
j 5°1.1 
I 
375.02 
+ 6.54 
-0.84 
+ 12.30 
86071.28 
ExP. R R. October 1. Graham making 86520.71 vibrations. 
Barom. 1 30 " 152 54 } 30 - I51 J + .019 Capill. 5 -.060 to 32° = 30. 1 10. 
1 •• 
1 50.8 
31 52.5 
m s 
41 33 
48 57 
ms h m s 
41 40 9 41 36.5 
49 22 0 49 09.5 
6.81 x 1.05 = 6.85 
0.21 x 1.05 = 0.22 
j 5°1.65 
375.10 
. 1 
+ 0.47 -0.59 
+ 12.28 
86071.52 
