158 REV. F. FALLOWS’S OBSERVATIONS WITH AN INVARIABLE 
3rd, — Mr. Fallows. 
Vibrations in a Mean Solar Day. 
Mean of 401 coincidences =86097-67 
Mean of 419 =86097.66 
Mean of 507 = 86097-70 
Mean of 81 = 86097-69 
True Mean of 1408 = 86097-68 
Summary at the Cape. 
Vibrations in a Mean Solar Day. 
Captain Ronald. . True Mean of 630 coincidences = 86097-73 
Mr. Johnson . . . True Mean of 420 = 86097.83 
Mr. Fallows . . . True Mean of 1408 =86097.68 
True Mean of 2458 = 86097-72 
From this last conclusion, compared with that obtained by Captain Sabine 
at Mr. Browne’s, in Portland Place, and which only differs -,Vth of a vibration 
in a day from Captain Ronald’s subsequent determination, the compression of 
the earth is very readily ascertained. 
Let n = the difference in the number of vibrations of the pendulum at 
London and the Cape. Then for 
C -rro- n = 65.752 
Compression < n = 67-344 
v- 15-6-0 n — 68.828 
London. No. of vibrations in a mean solar day . = 86164.64 Sabine. 
Cape. No. of vibrations in a mean solar day . = 86097-72 
66.92 
Reduction due to difference of level from low- water mark = 0.20 
True difference in the No. of Vib ns in a mean solar day . = 67-12 
This quantity gives the compression of the earth . . = 
