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in such a manner as to bring up the ends of a great thickness of 

 beds of rock to the same general level at the surface. 



Accordingly, confining our attention for the present to the strata 

 newer than the Silurian rocks, we find that, while the vast pile of 

 Carboniferous rocks that the wild upland tract extending from the 

 eastern boundary of Edenside into Yorkshire has been shaped out 

 of yet retain much of their originally-horizontal position, there are 

 other tracts of the same rocks, lying side by side with these hori- 

 zontal strata, and now forming much of the low ground of Edenside, 

 that are tilted in such a manner as to bring the edges of a very 

 considerable thickness of rocks to the surface within a distance of 

 only a few miles. 



Some idea of the relation of these tilted strata to the beds that 

 are less disturbed may be gathered by laying half a quire or so of 

 sheets of stififish paper of various colours, or an old copy-book, on 

 its side, and making a clean cut right through from about the 

 middle nearly to the outer edge. If it now be pressed endways in 

 the direction of the incision, it will be easy to force the paper on 

 one side of the cut to arch in an upward curve while that on the 

 other bends in the opposite direction ; the papers at each end of 

 the cut remaining all the while in their original position. It will 

 then be easy to see how any individual sheet is opposed, on one 

 side of the incision, first, by the corresponding part of the same 

 sheet on the other side, and then by successively higher, or lower, 

 sheets, as the case may be, up to the point of greatest curvature. 

 Beyond that point it will be noticed that the vertical distance 

 between the positions of the same sheet on each side of the cut 

 gradually lessens, until, at the farther extremity each sheet on one 

 side of the line is again level with its corresponding part on the 

 other. Imagine the pile of sheets ot paper to represent a great 

 series of deposits accumulated from beginning to end without any 

 important breaks in the succession ; the surface of the copy book, 

 an area of a few hundred square miles ; the incision, a line of 

 weakness where the rocks have given way over a still older line of 

 fracture in the rocks underlying the strata represented by the 

 sheets of paper ; and, finally, the action of the bands in bending 



