Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/125

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It is important because it has been stated by Mr. Forster (in his section from Newcastle to Cross Fell) that this red sandstone of the plain is the lowest stratum of the above series, and because its position at the base of the escarpment, both on the north of Melmerby towards Brampton, and on the south of Murton towards Brough, would without careful investigation lead to such a conclusion.

But the section that has been described from Melmerby to Dufton proves that the old conglomerate is the only rock that exists there between the limestone series and the slate, and our examination of the base of the escarpment north of Melmerby from Croglin to Castle Carrick pointed out the source of this error, which is so common that we could not find an individual who did not believe in it, though not one had ever seen a section that proved the fact.

The source of this natural and almost necessary error, is the low position of the red sandstone at the base of the immense escarpment, [1] where it abuts so bluff against the abrupt and truncated extremities of the lower strata of the great limestone series, is in such absolute contact with them, and so accommodated to their irregularities, which it fills up, and seems as it were to notch into them, that it would be almost impossible to avoid the error which is so popular, without looking to the general history of this stratum, and to the sections which display junctions at the edges of the plain of Carlisle, in which this new red sandstone forms the upper and most extensive deposition.

One of these sections has been given near Melmerby: another may be seen in the cliffs between Whitehaven and St. Bees Head. [2] These are lofty, and present a distinct perpendicular section, in which it is seen at the point of the junction nearly two miles south-west

  1. see Section, Plate 5, No. 1, C. D. E.
  2. Plate 5, No. 4.