Denudation of the Lake District. 469 



nations of the observed phenomena of elevation and denudation. 

 The general boundary of tract may be considered as sufficiently 

 defined on the north by the band of mountain limestone which runs 

 from Kirkby Stephen by Heskel, on the west by the coast, and on 

 the south by the discontinuous and irregular band of limestone, 

 which again nearly meets the great mountain limestone ridge of 

 Yorkshire, by whfch, and the great fault along its base, the district 

 is bounded on the east. The general strike of the limestone beds 

 at any point, as well as that of the new red sandstone reposing upon 

 them, coincides with the direction of the boundary at that point, 

 except on the east, where the boundary is the great fault just men- 

 tioned. Consequently the dip is nearly perpendicular to the bound- 

 ary, and round the western side is divergent from the extremity of 

 the axis of the district, which may be considered to extend from 

 near Scaw Fell over Kirkstone and Howgile Fells. On the west 

 the dip frequently amounts to between 20° and 30° ; and it should 

 be remarked, that it appears to be very nearly as great in the new 

 red sandstone beds as in those of the subjacent limestone. The 

 mountain limestone reposes unconformably on the older formations 

 which, within the limestone band, occupy the surface. The gene- 

 ral strike appears to be somewhat north of N.E. and south of S. W. 

 The surface of junction of the mountain limestone and the older 

 formations beneath can be well examined in many places, and the 

 author concludes that the surface on which the limestone was de- 

 posited must have been an even surface in the same sense in which 

 the expression may be now applied, for instance, to the bottom of 

 the German Ocean. He also concludes that this surface must have 

 been horizontal. This will necessarily follow from the previous in- 

 ference, unless it be contended that those animals whose remains 

 are now found in the lower limestone beds could exist in the per- 

 fect performance of all the functions of life, at the depth of several 

 thousands of feet, under an enormous pressure and in darkness, as 

 well as at small depths, under small pressure and in the light of the 

 sun. 



This surface of junction wraps round the outer portion of the 

 district, and, if continued as an imaginary surface, over the central 

 portion in the manner which the inclination of the existing portion 

 would obviously suggest, it would pass considerably over the tops 

 of the highest mountains of the district, to which it would form a 

 complete envelope. Hence it follows that if the movement which 

 produced the geological elevation of the existing portion of the sur- 

 face of junction affected the central portion of the district in the 

 same manner as in all analogous cases in which the evidence is 

 complete, it will follow that the present surface of the Cumbrian 

 mountains must have been beneath the surface of the ocean at the 

 commencement of the deposition of the mountain limestone. The 

 truth of this conclusion involves that also of the original horizon- 

 tality of the surface of junction. 



The stratification of the older rocks of the district can afford no 



