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GEOLOGY called Alport Towers, and has been formed by masses of Shale Grit which have slipped down from the hills above. The ridge between Lose Hill and Mam Tor is capped by the Shale Grit. The beds dip north, and at Castleton, a short distance further south, we find the Mountain Limestone dipping under the Limestone Shales and Shale Grit. In the Edale valley the river Noe has cut down through the plateau of Shale Grit to the Limestone Shales below it. An anticline runs along the north flank of the valley, and on that side the Limestone Shales are brought out by the rise of the beds. Good sections of these grits may be seen in the ' cloughs ' which run down from Kinder Scout into Edale. At right angles to the anticline above mentioned, another runs through Edale Chapel and Mam Tor in a north-westerly and south-easterly direction. This anticline if produced would pass through the middle of the Mountain Limestone district, and it has been considered that it marks the direction of the Pennine upheaval. A dome shaped mass of the Yoredale Shales is brought up in the middle of the valley, and the sandstones of Mam Tor are raised up to a greater height than the Shale Grit of Lose Hill. Mam Tor, or the Shivering Mountain, with its precipitous face of some 200 feet in height, consists of sandstones inter- calated with shales. In the latter Goniatites and Posidoniella have been found. A great part of the hill has fallen and carried away with it a portion of the Roman entrenchment which was made round the hill not far from its summit. At the foot of the tor the Yoredale Shales are faulted against the Mountain Limestone near the Blue John mine. The present turnpike road from Castleton to Chapel-en-le-Frith and Buxton passes over masses of grit and shale which have at some time slipped from the face or base of Mam Tor. These hummocks form an insecure basis for a road, as, from the shape of the ground, there is nothing to prevent further slipping. In the winter of 1901-2 small portions of the road slipped, and some ominous cracks which were present when these pages were being written indicated that some further portions of the road might slide down the hill at the next ground thaw. The alternation of sandstones and shales has a tendency to produce landslips, especially when the rock dips into the valley. Perhaps the most striking of such landslips is Alport Tower. The eastern bank of the river Alport is covered with landslips formed by masses of Shale Grit which have slid down from the hill above. In one place the fallen mass is about 28 chains in length and 12 in breadth. At Coumbs Wood near Matlock the outlier of Shale Grit is in the form of an anticline, the beds on both sides dipping away from the hill. On both sides of the hill large masses of the grit have slipped away into the valley below. The fourth, or Kinder Scout Grit, consists of two thick beds of sandstone separated by shale. The lower one dies away on Bamford Edge, and is not found further south. The upper varies from a coarse grit to a fine grained sandstone, and generally forms bold craggy cliffs 21