324 Captain Kater’s account of Sir Thomas Brisbane's 
resulting compression ; the length of the pendulum vibrating 
seconds at London being taken at 39,13929 inches. 
The experiments at Paramatta being compared with those 
made by me at Unst, in latitude 6o° 45' 28" north, give 
,0053605 for the diminution of gravity from the pole to the 
equator, and for the resulting compression. 
If Mr. Dunlop’s experiments at Paramatta be compared 
with those made at London, we obtain 39,07751 for the 
length of the seconds pendulum at Paramatta, ,0052238 for 
the diminution of gravity from the pole to the equator, and 
— 1 ■ for the compression. Or, comparing Mr. Dunlop’s 
experiments with those made at Unst, we have ,0053292 for 
the diminution of gravity from the pole to the equator, and 
- — for the resulting compression. 
The compressions here deduced must not as yet be deemed 
conclusive, for it is well known that a very small alteration 
in the number of vibrations made by the pendulum would 
occasion a considerable difference in the fraction indicating 
the compression. The indefatigable zeal of Sir Thomas 
Brisbane, will, however, no doubt soon furnish additional 
data. 
I have the honour to be, 
My dear Sir, 
very sincerely yours, 
HENRY KATER. 
London, 
June, 18Z3. 
