368 Capt. Kater’s experiments for determining the variation 
By the Stars, ist. Series. Leith Fort. 
From 
To 
Computed Vibra- 
tions in a mean 
solar day. 
Mean of 
Transits 
B.or A.coin. 
Correc- 
tion. 
Corrected vibra 
tions in a mean 
solar day. 
No. of stars 
observed. 
Inter, of 
transits. 
h. m. 
i A. M. 
2 P. M. 
86073,04 
B. 1.33 
+ ,05 
86073,09 
4 
2 
1 A. M. 
4 P. M. 
86073,16 
B. 0.28 
+ ,02 
86073,18 
7 
4 
3 A. M. 
4 P. M. 
86073,28 
B. 0.27 
+ ,02 
86073,30 
6 
2 
By disappearance 1 
of stars 
behind 
OO 
ON 
O 
LkI 
To 
A. 0.33 
,02 
86073,19 
2 
7 
Leith steeple. J 
By the Sun. ist. Series. 
2 P. M. 
5 A. M. 
86073,17 
A. 0.57 
—0,3 
86073,14 
2 
3 
2 P. M 
6 A . M. 
86073,28 
A. 1. 9 
—0,3 
86073,24 
2 
4 
5 P. M. 
6 A. M. 
86073,57 
A. 0.51 
— 1 °>3 
86073,54 
2 
1 
Using the number of stars observed and the intervals of the 
transits, as before, to obtain a mean, we have 86073,19 vibra- 
tions by the stars, and 86073,23 by the sun, and the sums of 
the factors, being 62 and 16, we obtain 86073,20 for the final 
mean number of vibrations in 24 hours. 
The mean height of the barometer was 2 9,75 inches, and 
the mean temperature 59°,6. The correction for the buoyancy 
of the atmosphere is therefore 3,99. 
The height of the pendulum above low water, was found 
by levelling to be 68 feet, whence we have 0,28 x ffo = 0,18 
for the correction due to this elevation. 
These corrections being applied, we obtain 86079,37 for the 
number of vibrations made by the pendulum in a mean solar 
day in vacuo, and at the level of the sea. 
The clock was now taken down to be cleaned, as I had re- 
solved to go through a new series of observations. On 
examining the oil, it was found to all appearance as pure as 
