from Penigent to Kirkby Stqyhen. 85 



cavern, with perpendicular walls, from which may be heard the roaring of 

 subterranean waters. The latter, an open crevice of unknown but great 

 depth, as is proved by the long-continued rumbling noise of the stones which 

 descend after many rebounds from its projecting ledges towards the foun- 

 dations of the mountain. 



Below Dowgill Scar is a beautiful junction of the horizontal limestone and 

 inclined greywackc without the intervention of any conglomerate*. In the 

 prolongation of the section through Moulton Fell, the Scar limestone presents 

 no features deserving peculiar notice ; but a little to the east of the line, 

 above the village of Selside, is an open chasm called Alum Pot, of enormous 

 but unknown depth. It is surrounded by grassy shelving banks, and many 

 animals tempted towards its brink have fallen down and perished in itf. 



Further up the hill (at Moor Syke, &c.) are the black marble beds (No. 3.), 

 and after passing in succession all the intervening beds, we have, at the top of 

 Simon Fell, the slate quarries of No. 8. c. The upper portion of this group 

 makes a magnificent precipice on the north side of Ingleborough, and its 

 slate quarries may be traced all round the mountain. Over this group comes 

 a precipice of limestone, in which (as at Penigent) the twelve-fathom and the 

 four fathom limestones are united, the intervening shale and coal (No. 10.) 

 having nearly disappeared. Over these comes the upper shale (No. 12.); 

 and then the first millstone grit (No. 13.), forming a great tabular mass on 

 the top of Ingleborough. The two highest groups of the Penigent section 

 are therefore wanting. 



In descending from the great precipice of slaty grit and shale to the river 

 of Chapel le Dale, we pass in regular succession over every group from No. 8. 

 to the bottom of the Scar limestone. The upper groups are much concealed 

 by morass, but they break out, here and there, and are laid bare in the water- 

 courses on the sides of the mountain. In the bottom of the valley (about 

 half a mile below the Chapel) there is a beautiful junction of the horizontal 

 limestone and the inclined greywacke ; and just at that point all the mountain 

 streams, which in the higher part of the valley had been engulfed in the 

 cavernous Scar limestone, burst out in one copious spring, and form the river 

 which descends to Ingleton. 



Following the Hne of section, we have at the base of Whernside some of 



* The greywacke dips about south by west, at an angle of 45°. 



t The approach of cattle is now prevented by a strong, lofty wall ; but there can be little doubt, 

 that during the last two or three thousand years, great masses of bony breccia must have accumu- 

 lated in the lower parts of this great fissure, which probably descends through the whole thickness 

 of the Scar limestone. 



