278 NOTICES OF THE MEETINGS (March 11, 
WEEKLY EVENING MEETING, 
Friday, March 11. 
Tus Duxe or NortHuMBERLAND, K.G., F.R.S., President, 
in the Chair. 
Joun Puiturrs, F.R.S., G.S., &e. 
Geological Sketches round Ingleborough. 
Tue Lecturer prefaced his observations on this the most con- 
spicuous of the Yorkshire Mountains, by a brief allusion to cir- 
cumstances which, at an early period of life, had fixed his earnest 
attention on the scenery and natural history of the country which 
surrounds it. 
Viewed in any direction, Ingleborough appears a grand and 
solitary mass, chiefly composed of shales and sandstones, super- 
posed on a broad floor of limestone which rests on a basis of 
upturned Lower Paleozoic Rocks. The great limestone floor 
and the lower rocks are broken off and thrown down to the south 
and west of the mountain, by the enormous, often double, dislo- 
cation called the ‘ Craven Fault,’ and the ground falls in these 
directions nearly 2000 feet below the summit. Hence the con- 
spicuous character of the mountain, which rises to the height of 
2380 feet above the sea. 
The streams which gather on the slopes of Ingleborough and 
Penyghent run in small channels downward over the shales and. 
sandstones, but, on reaching the limestone, they are swallowed up 
in deep gulphs of that rock, and after passing through caves, 
many of which are remarkable for beauty, issue to the surface in 
picturesque channels, and sometimes make pleasing cascades, 
such as Thornton Force. The most famous of, these caverns, 
which was discovered by the present proprietors of Ingleborough, 
and traced by them for a length of 702 yards, has, no doubt, been 
formed by the long continued erosion of a stream which, after 
gathering on the slopes of Ingleborough, plunges into a deep 
chasm of the limestone called ‘ Gaping Gill’ ; its-erosive power 
being augmented by the sand and pebbles which it hurls down. 
The interior of this cave is wonderfully varied in form, and 
enriched by every variety of sparry accumulation — slender pipes, 
spiral columns, swelling bosses, broad expansions, and, most 
beautiful of all, white sheets of carbonate of lime which spread 
like leaves on small basins of the clearest water. From researches 
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