in the length of the pendulum vibrating seconds. 507 
By the Trigonometrical Survey, Dunnose appears to be 
792 feet above the level of the sea ; the height therefore of 
the Pendulum above the sea was 253 feet. 
Observations with a Barometer of Sir H. Englefield's con- 
struction at the Isle of Wight. 
Date. 
Ther- 
mometer. 
Stations. 
Barometer. 
inches. 
Calculated 
height, 
and correction 
Feet above 
high water 
mark. 
May 12 
0 
62 
Summer house. 
LkJ 
0 
0 
00 
61 
High water mark. 
3 o } 3 H 1 
217,2 
63 
Summer house. 
30,092 J 
+ 7,° 
224,2 
15 
62 
Summer house. 
30,036 ? 
209,8 
+ 6,7 
61 
High water mark. 
30,260 j 
216,5 
16 
61 
Summer house. 
30,015 ] 
56 
Beach (2 ft. above h. water,) 
30,227 L 
212,8 
^ 61 
Summer house. 
30,008 j 
+ 7,° 
+ 2,0 
— 
221,8 
Mean 
220,8 
15 
60 
Dunnose, 
29,499 ^ 
61 
High water mark. 
30,260 j 
707,7 
+ 22,8 
730,5 
60 
Dunnose, 
29,499 l 
62 
Summer house. 
30,036 j 
497,4 
+ 16,1 
513,4 
The correction applied, is ~ of the calculated height on 
account of the rise of the mercury in the cistern of the baro- 
meter. 
From the preceding table we have 
Dunnose above the Summer house by Trigonome- 
trical measurement, - 
By the Barometer, - 
Feet 
539 >° 
513-4 
Difference, - 2 5,6 
3 U 
MDCCCXIX. 
