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 GEOLOGY The Mountain Limestone from Doveholes through Castleton and Bradwell to Eyam is bounded by a narrow belt of lower ground con- sisting of Yoredale Shales. Slopes which run nearly parallel to the limestone boundary rise from the depression. These slopes are the edges of several outliers of shale grit which once formed a large plateau which extended from Chapel-en-le-Frith to Eyam, and included the moors in the extreme north of the county. Edale and the valley of the Derwent near Hope, Bamford and Hathersage have divided this plateau into several outliers. Near the centre of the shale grit plateau is an outlier of Kinder Scout grit, which is called the Peak. Though a flat tableland, it reaches a height greater than any other part of the county, some portions of it being 2,000 feet above the sea. The shale grit dips under the Kinder Scout grit, which on the west forms a ridge from Chapel-en-le-Frith through Hayfield to Glossop, and on the north extends some distance east from Glossop into Yorkshire. The various members of the Millstone Grit series may be traced as far south as Belper. The Chatsworth or Rivelin Grit forms the fine escarpments of Froggat Curbar and Baslow Edges, east of Stoney Middleton, and that of Crow Chine near Ladybower. On the west as far as Doveholes the limestone is bounded by the Yoredale Shales, though the boundary is often faulted. In the neighbourhood of Earl Sterndale the boundary is greatly complicated by faults, and west of Buxton the limestone is faulted against the Yoredale Shales and shale grit which dip under the Millstone Grit of Axe Edge and the Goyt Basin. Between Buxton and Doveholes the limestone is bounded by the Yoredale Shales, which dip under the Millstone Grit of Combs Moors on the west. The greater portion of the rocks of Derbyshire belong to the Carboniferous Series. This is succeeded by the Permian, which only forms a narrow strip near the eastern boundary of the county, and the Trias, which is confined to the southern part. The Jurassic formation is unrepresented, and the Pleistocene deposits are found in places covering the carboniferous and Triassic rocks. The Peak district has a world-wide reputation for beautiful scenery, and well illustrates the intimate relation which exists between rock struc- ture and scenery. The Toadstones, which were first investigated by Whitehurst in 1778, furnish evidence of the volcanic activities which prevailed at intervals during the deposition of the Mountain Limestone and the shales and limestones immediately succeeding it. The Moun- tain Limestone is interesting not only because of the fossils it contains, but on account of its numerous caverns and underground streams, its mineral waters, which have since the time of the Romans been famed for their medicinal properties, and its lead mining industry, with the curious and antiquated laws by which it is governed. The old mine heaps which disfigure parts of the county bear testimony to the great activity of this industry in bygone days. Coal is the most important and largely worked rock in the county. Limestone is quarried largely for road metal, lime burning and building, 3