in the length of the pendulum vibrating seconds. 383 
from the former result 22 feet. The height of Dunnose above 
the summer house, was also deduced barometrically, and 
appeared to be 513 feet, differing from the trigonometrical 
determination 2b feet in defect. If this difference be attributed 
to error in the barometer, as is most probably the fact, the 
proportional error in the elevation of the summer house, 
determined barometrically, will be 11 feet, and this being 
added to 231 feet, we have 242 feet for the height of the 
pendulum above the level of the sea, which is probably within 
eleven feet of the truth. 
The correction due to an elevation of 242 feet, is 0,997 x 
fo = 0,70 ; and this, together with the correction for the buoy- 
ancy of the atmosphere being added to the number of vibra- 
tions before found, we obtain 86058.07 for the number of 
vibrations which would be made by the pendulum in a mean 
solar day, in vacuo, and at the level of the sea. 
