Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/547

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1869.] MACKINTOSH—LANCASHIRE AND CUMBERLAND DRIFTS. 423


Ulverstone in terraces or knolls in the direction of Bardsea. A section of it, excessively contorted, may be seen in a pit at Gascow, near Conishead Priory. At Wadhead the sea has cut away about half of a sand and gravel knoll, containing unsteadily striated boulders and seams of consolidated sand. I have not had an opportunity of tracing the sand and gravel further south. West of Ulverstone it extends continuously for nearly two miles. It appears in the railway-cutting close to where the Dalton Road crosses the railway; and a section of it revealing false-bedding may be seen at the end of a row of cottages called Three Bridges. On the side of the road from Dalton to Ireleth, and in knolls to the S. and S.E. of Ireleth railway- station, and elsewhere in the neighbourhood, sections of it have been exposed. Between Ulverstone and the Duddon it reaches an altitude of at least 200 feet. Near the summit-level of a wide pass or saddle between Penny Bridge and Arrad Foot (north of Ulverstone) a number of pits have been dug in a gravel knoll. At the bottom of one pit I observed very hard typical pinel with boulders, underlying stratified sand and gravel. In another pit a bed like pinel and nearly as hard, but stratified, rose up to the surface in the form of a semi-arch. Another pit revealed obliquely bedded gravel and sand; a fourth pit, dark sand under compact gravel. The beds in all the pits were very much contorted; the pinel here and there seemed to run into beds of compact gravel; and in other respects the drifts resembled those of the Ulverstone railway-section. A farmer told me that a knoll to the S.W. consisted of similar sand and gravel. The altitude of these drifts is between 200 and 300 feet above the sea. In the valley of the Crake an ochreous drift with numerous scratched boulders runs down to the level of the river; and in this district we find an illustration of a fact which I believe to be of universal application in all districts containing erratic boulders: the rivers or brooks have nothing to do with the drifts lying in or near their courses further than reasserting them over very limited areas. It ought not to be forgotten that in North-west Lancashire (and, I believe, in many other districts) the middle sand and gravel is more frequently found on plains, watersheds, or hill-sides than in what may be strictly called river-valleys*.

g. Pinel at High Levels.—It has just been stated that pinel may be found under the middle drift on the pass between Penny Bridge and Arrad Foot. Near to Beckside hamlet a good instance of its frequent mode of occurrence at high levels may be seen. It occupies small hollows in slate rocks with planed-off edges. Pinel runs up the sides of the hills to considerable altitudes between Beckside hamlet and Ulverstone, and in some places it looks like an old sea-beach or the remnant of a once extensive deposit still fringing or clinging to the mountain-slopes. About Lindal pinel may here and there be seen exposed in pit- and road-sections at levels varying from 250 feet to upwards of 300 feet above the sea; but much of of what is called loose pinel in this district is probably upper drift.

  • The pinel in hilly countries occurs frequently at the bottom of valleys and

gullies, from which it thins out upwards along the slopes.