Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/725

 but, as both occur on the Surface, the distribution of the former must also have been continued during that of the latter.

The moory ground which lies immediately east of Wastdale Crag has its surface marked by several mounds of sand and gravel. These have all the aspects of Eskars ; and they contain rounded fragments of Wastdale-Crag granite. These mounds may, however, have been formed at a more recent date than those Eskars which, in the valley of the Eden, yield blocks of Criffel granite.

With respect to the surfaces of the rocks upon which the Boulder- clay rests, these surfaces in many instances exhibit glacial scratchings. One of the localities which afford these scratchings is at a short distance east of Gaythorn Tile-works. Here, in a small quarry, the surface of the Carboniferous limestone is beautifully marked with striae, which have a nearly north and south course.

These striated rocks, which were seen by Sir Charles Lyell, Mr. M'K. Hughes, Dr. H. A. Nicholson, and myself, seem to have been first noticed by Mr. Lightfoot, who was formerly on the Geological Survey, and who was for a while engaged in this portion of Westmoreland. The striated surface of the limestone here has a thin bed of Boulder-clay resting upon it. The direction of the striae follows the course of the valley, and is almost at right angles to the line taken by the Wastdale-Crag granite blocks, which overlie the Boulder -clay in this neighbourhood.

Glacial strias may be seen in several localities in Westmoreland; and wherever they occur their direction corresponds to the course of the valleys. This is the case not only with the vales of the Lyvennet and the Eden, but also with those small dells which contain the tributaries to these streams. The same circumstance is seen likewise in the valley of the Lowther, a river which has its origin, in part, from Wastdale Crag, and which, after flowing northwards, joins the river Eamont about a mile south of Penrith. These striae, formed by ancient glaciers, and running in the direction of the present valleys, indicate that the drainage of the country and its present outline have not been much altered since the operation of glacial action; and they strongly support the inference that the outline of this portion of Westmoreland approached pretty nearly to what it is now during the time when the Wastdale-Crag blocks were being distributed.

On referring to the hill- shaded inch-to-the-mile Ordnance-map of the district where the granite blocks occur in the greatest abundance, it will be seen that this portion of Westmoreland is occupied by numerous small valleys having a north and south direction, a course corresponding to that of the stria) which these valleys afford. Many of these small valleys have steep escarpments facing towards the west or towards the granitic area of Wastdale Crag. The valley of the Lyvennet also exhibits the same features. It is in this direction that the limestones and other rocks of the Carboniferous formation have their outcrop. On the east side of the vale of the Eden, the same circumstance manifests itself in the bold western outcrop of the rocks which form the Pennine chain; and even

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