324 North of England. 



that the physical features of England and Wales present 

 masses of Palseozoic rocks, forming groups of mountains 

 in the west, then certain plains and undulating grounds 

 composed of New Ked Sandstone, Marl, and Lias, and 

 then two great escarpments, the edges of tablelands, 

 which rise in some places to a height of more than a 

 thousand feet : the western one being formed of Oolitic, 

 and the eastern of Cretaceous strata, which, in its turn, 

 is overlaid by the Eocene series of the London and 

 Hampshire basins. See fig. 57. 



If we now turn to the north, what do we find there ? 



Through the centre of this part of England a great 

 tract of Palseozoic country, more than 200 miles in 

 length, stretches from the southern part of Derbyshire 

 to the borders of Scotland, and joins with the hilly 

 ground of Berwickshire. It consists of Carboniferous 

 rocks, ranging from the Carboniferous Limestone up to 

 those that pass beneath the base of the Permian strata. 

 Further west, between Morecambe Bay and the Sol way, 

 lie the Silurian and Carboniferous rocks of the Cumbrian 

 area, separated from the Carboniferous formations of 

 Northumberland, Durham, and Yorkshire, by the Per- 

 mian beds of the Vale of Eden. 



As far as the north borders of the Lancashire and 

 Yorkshire coal-fields, the Carboniferous rocks lie in the 

 form of a broad anticlinal curve. 



At the southern end of this area, a wide tract of 

 Carboniferous Limestone hills ranging up to 1,200 feet 

 in height, occupies the centre of the anticlinal curve, on 

 each side of which, the Yoredale shales and thick strata 

 of Millstone grit dip east and west as the case may be. 

 The latter, being interstratified with comparatively soft 

 beds of shale, run in long bold escarpments (fig. 63), that 

 often trend north and south both on the west and east sides 



