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west they dip out of sight and are covered by the Coal- 
measures, of Lancashire and Staffordshire on the one side, 
and of Yorkshire and Derbyshire on the other. Of the latter 
great coal-field, the district we are now in forms an important 
part. 
I have now endeavoured to give a history, first of 
the method of formation of the rocks found in the Car- 
boniferous area of the north of England, and secondly of the 
manner in which they were brought into the position they 
now occupy. I would yet say a word on the connection 
between the scenery of the different parts of the country 
and the rocks of which they are formed. 
On passing from the New Red Sandstone central plain into 
the northern Carboniferous district there is a sudden change 
of scenery which cannot escape notice. The first is low 
lying ; broken by mounds rather than hills ; with no 
well marked or persistent ridges ; fertile and well cultivated: 
the latter rises into lofty hills ; is traversed by long steep 
" edges " often running for miles parallel to each other, in 
lines nearly straight ; and a great part of it is bleak and 
barren moorland. Within this Carboniferous tract, too, 
distinct features in the scenery mark out the parts occupied 
by the three divisions of the rocks. But we must first say 
how these features have been produced. It was explained 
some time back that immense masses of the rocks must have 
been removed by the wearing action of the sea : this action 
tends to plane everything down to a nearly uniform level, 
and when it ceased the country probably was one immense 
plain. On this rain would fall, and, gathering in any little 
inequalities of the surface, form brooks, which would step by 
step cut deeper into the plateau, and, aided by rain, frost, 
and other sub-aerial forces, at last carve it out into its present 
form of hill and valley : consequently this form ought to 
depend very much upon the nature of the rocks acted on ; 
