Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/718

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their way over the watershed between Augill beck and Black beck, and that over this watershed, at a height of about 1490 feet, the great bulk of the boulders which occur in the country east of the Pennine chain have passed.

A block of this granite can be seen on the eastern side of this watershed, a short distance to the S.E. of Harton Crag, which is near the summit of the ridge ; and Prof. Phillips mentions the occurrence of these blocks on the summit of an isolated hill called Goldsborough, which lies about 6^ miles east of this watershed*. They are also to be met at lower levels in the valley of the Balder. But Wastdale-Crag granite blocks are by no means so abundant here as are boulders of porphyry, which have also come from the eastern sides of the Westmoreland portion of the Lake-district mountains.

A parallel valley runs eastwards at the distance of about 2-1/2 miles south of Balderdale. In this valley, called Deepdale, Wastdale- Crag granite blocks, associated with porphyries, also occur. Some of the former, which are of a large size, are seen in the lower part of this vale, in the neighbourhood of Lartington.

Reverting again to the eastern limits of the dispersion of Wastdale-Crag blocks in Westmoreland, we have the steep front of the Pennine chain forming this boundary north of the watershed above alluded to. In Westmoreland, this chain has nearly a N.W. course.

Blocks of granite are, however, by no means abundant on its sides, but they have been recognized by Dr. H. A. Nicholson and myself at a height of about 700 feet above the level of the sea, in the course of Pusgill beck, at a short distance to the N.E. of the village of Dufton.

The area in Westmoreland over which Wastdale-Crag blocks have been distributed, although irregular in its outline, has somewhat of a triangular form. Its greatest breadth is in an E.N.E. direction, namely, from Wastdale Crag to the watershed separating Augill beck and Black beck; and this distance amounts to 19 miles. In a north and south direction the greatest recognized length of distribution is from Long Wathby to a little south of the village of Langdale, near Tebay, which is 18 miles.

In the area of distribution of the Wastdale-Crag blocks there is a wide difference in the abundance in which those blocks occur. Near the western margin of the area they are found in great plenty within about three miles from their parent sources. Beyond this they become less abundant, and near the northern limit of the area they are very rare. Near the eastern boundary, which is at a considerable distance from the parent mass, they are by no means common, except near the line of their route across the Pennine chain.

With reference to the more central portions of the area of distribution in Westmoreland, there are also great differences in various localities in the quantities of their granite blocks. Two valleys

  • Op. cit. supra. Professor Phillips applies this name to a hill different from

that which bears it on the map of the Ordnance Survey.