Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/548

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424 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 23,


On walking from Ulverstone to Beckside village (Kirkby Ireleth district), over the intervening hilly region, the pinel may be traced almost continuously. On ascending the hill the gutter in the road-side reveals about the hardest and most typical pinel I have yet seen. Its colour is almost invariably yellowish brown. Valleys have been filled up with it to a certain height; and brooks have excavated their channels in it. Beyond a house called Harlock, and along the east and north side of a round hill called Longslack, it runs continuously, and presents all the most typical characteristics of the formation, including large striated boulders. In most places it seems to have been covered to a slight depth with loose angular detritus. The pinel covers the greater part of the watershed of the flat shallow pass between the Longslack and Crag-Height eminences, where it reaches an altitude of about 800 feet above the sea. It may be traced running down the western side of the pass, where it has not been covered with Upper Boulder-clay. It may possibly run under the estuary of the Duddon so as to form a more or less continuous deposit with the pinel on the other or Cumberland side of the river. The accumulation of the pinel mantling round Longslack, and probably many of the neighbouring hills, might at first sight suggest the idea of a great flow of land-ice ignoring hill and valley; and yet there would appear to be some difficulty in supposing land-ice capable of leaving a continuous spread of pinel clinging to the convex side of a hill and covering a wide shallow pass, as in the locality under consideration.

h. Upper Boulder-clay.—Where the ground begins to decline on the western side of the above pass, the pinel gradually dips beneath a rubbly clay. Lower down, on the Soutergate-road-side, at a height of about 700 feet above the sea, the line of demarcation between the pinel and this clay is very distinctly marked. Still lower down this clay presents features which can leave no doubt that it is of Upper-Boulder age. The channel excavated in it by the Cross beck reveals a thickness of at least 100 feet. In several places it may be seen resting on the denuded edges of slate rocks. It contains many smoothed, polished, and striated boulders. At a lower level, on the road-side, pinel occasionally makes its appearance underneath this upper drift. The pinel is hard and of a yellowish-brown colour*; the upper drift loose and of a reddish colour. At a still lower level a small boulder of granite, a sign, I believe, of Upper Boulder-clay in this district (see sequel), made its appearance; and all along there were many boulders of porphyry and other rocks, which must have been floated across the valley intervening between this hill-side and the green slate and porphyry mountains. On many of the boulders the striae were bent across each other in a remarkable manner. At a small quarry above Gargreave, and about 250 feet above the sea, I saw the edges of compact slate rocks planed down and slightly grooved, the direction of the glaciation being 10° W. of N., or ob-

  • On the other side of the depression traversed by the Cross beck, as may be

seen on the Beckside road, the upper drift has in most places thinned out, the pinel coming to the surface.