50 6 Capt. Kater’s experiments for determining the variation 
angle at Dunnose Station between the Obelisk and the Sum- 
mer house. 
The bearing of Sir Richard Worsley’s Obelisk, according 
to the Trigonometrical Survey, is 87°.43 ; .4o north-west from 
the meridian of Dunnose; therefore the bearing of the Sum- 
mer house appears to be bo^S'.n'' north-east, and the re- 
sulting distance on the meridian 1893 f eet - 
May 12th, the following observations were made with the 
Repeating Circle, for obtaining the Zenith distance of the top 
of the Signal Post. 
Level. 
Readings, &c. 
+ 2] 
4 16 
+ 6 
+ 7 
+ n 
+ 10 
+ 18 
+ 14 
— 5 
— 12 
— 22 
— 20 
— *7 
— l 9 
— 10 
— 18 
. O / // 
1st Vernier - 292.54. 5 
Second • 0 
Third - 5 
Fourth - 0 
Mean - - 292.54. 2,5 
Index - + 13,0 
Level - — 24,0 
4 360. 0. 0 
+ J °3 
— 123 
8) 652.53.51,5 
( + IO3 — 125 
Zen. Dist. - 81.36.43,9 
) // 1/ 
_ A ^3 4 - 
2 
From the above Zenith distance, and the distance of the 
Signal Post from the Summer house, we obtain 57 6 feet, for 
the elevation of the top of the Signal Post above the Summer 
house. 
The Signal Post was carefully estimated to be 30 feet 
high, and Dunnose Station is about 7 feet below the base of 
the Signal Post. Deducting therefore 37 feet, we have 539 
feet, for the elevation of Dunnose Station above the Pen- 
dulum. 
