Basin of the Eden and north-western Coasts of Cumberland, ^c. 397 



So far the account of the accompanying section, and of the successive groups 

 of rocks overlying the Whitehaven coal field, has been purely descriptive, and 

 unmixed with any hypothesis. The facts themselves contain, however, their 

 own interpretation. I have already stated that the lower sandstone, overlying 

 the Whitehaven coal field, resembled in structure the lower sandstone imme- 

 diately overlying the great Yorkshire and Durham coal fields. The former 

 contains, though very sparingly, impressions of Equiseta and Calamites ; and 

 so does the latter, as I have now ascertained, though I was unacquainted with 

 the fact at the time the detailed account of the structure of the magnesian 

 limestone series was published in a former part of our Transactions*. 



Again, though the "^Mower red sandstone" of Yorkshire and Durham ap- 

 pears, in some cases, to graduate into the coal measures (on which account it 

 was classified with them by Mr. Smith in his geological map of Yorkshire) ; 

 yet, when considered on a great scale, it is unconformable to them, and on that 

 account was separated from them and arranged, in the paper just quoted, as 

 the lowest member of the new red sandstone group. In the same manner, 

 in the coast section above described, the lower overlying sandstone appears 

 to be conformable to, and to graduate into, the coal measures of Whitehaven. 

 But, during many excursions in that neighbourhood, I have traced it from the 

 sea-side to the interior of the country, to the top of the hills above Dissington, 

 over the summit of Whillimoor, and to the crest of the hills overhanging Ar- 

 lecdon ; and thus ascertained that it spreads over the edges of the coal mea- 

 sures, and that, when considered in its whole extent, it is, as far as regards 

 the position of its lower surface, perfectly analogous to the "lower red sand- 

 stone" of Yorkshire and Durham. 



But the analogies do not end here. It is proved by several of the sections 

 published in a former part of our Transactions f, that the "lower red sand- 

 stone" in certain parts of Yorkshire had undergone considerable movements, 

 and been exposed to considerable degradations, before the deposition of the 

 magnesian conglomerate and magnesian Hmestone : for they are here and 

 there seen resting on its inclined edges, while in other places (for ex- 

 ample at Pontefract, in many parts of the County of Durham, and on the coast 

 of Northumberland), the "lower red sandstone" and magnesian limestone 

 graduate insensibly into each other, without any break of continuity what- 

 soever;};. Now we meet with precisely the same accidents of position in the 



* Vol. iii. p. 37. et seq. Very fine impressions of Equiseta or Calamites have been found in the 

 " lower red sandstone" of Hooton-Lovett in Yorkshire. 



f Geological Transactions, Second Series, vol. iii. Plate VI. figg. 3. 4. 5. 6. 

 X Ibid., vol. iii. p. 67. 



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