THE ORIGIN Of DERBYSHIRE SCENERY. 



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surface may be conveniently studied. It may 



not be out of place here to briefly mention the 



^ chief kinds of rock met with in Derbyshire. 



."2 First must be mentioned the mountain lime- 



s stone, which forms a broad anticlinal curve, the 



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■2 axis of which runs north and south. Fig. 1 is a 



I section across Derbyshire from west to east, and 



^ shows this anticlinal. Overlying the limestone 



I are certain shales and grits known as the Yore- 



.§ dale rocks ; and above these lie a group of 



= grits and shales, constituting the millstone grit 



I ^ formation. Over large areas the Yoredale and 



S 2 millstone grit have been completely removed by 



2| various denuding agencies, and the limestone 



|| thus brought to the surface. It is flanked east 



S g and west by the millstone grit, coal measures, 



^^. and newer formations. The limestone differs 



very markedly as regards hardness in different 



localities, and "weathers" in a very characteristic 



manner, presenting bold turreted cliffs and tors. 



•c The millstone grit also produces striking scenery, 



S although of a different type. This is especially 



1 the case where it is associated with softer rocks 

 ^ such as the Yoredale shales. Thus we find the 

 ^ hard millstone grit capping hills, while the softer 



2 Yoredale shales frequently form the valleys. 

 Fig. 2 is from a sketch made of the district 

 near Ashover, in which this is well seen. Fig. 3 

 is a section across this district, showing the dip 

 on either side of the anticlinal, along the ridge 

 of which the Amber has cut its channel. It 

 will be seen how well the grit withstands the 

 action of the weather, while the shales are 

 removed. There are many similar examples in 

 Derbyshire, but space forbids their citation. The 

 ?iiodus operandi of valley formation is peculiarly 



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