352 Mr. Outram on the Discovery, &c. 
the poles when in a revolving state ; and each ball is more or 
less furrowed in a latitudinal direction, as if, when revolving 
round its axis, and taking its fixed from a mor e fluid state , it 
had met with some resisting substance. 
Though the surface of this country is very rocky, it does 
not discover limestone any where within 20 miles of this tun- 
nel ; yet if the strata near the limestone at Buxton to the 
south, and at Clitheroe to the north, are examined, it will ap- 
pear probable that the base of these hills is limestone at some 
depth , and this fault discovered in the shale probably extends 
from the limestone bed beneath ; and the rib of limestone and 
balls, which, with other mixed substances, fill up this crevice 
or fault, were probably thrown thither from the mass beneath, 
by the volcanic eruption which first occasioned this break in 
the strata, or by some subsequent eruption of the same kind. 
