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ll dusk. I had spent several hours among its deposits when on my way to Portree, and several hours more when on my journey across the country to the east coast; but it may be well, for the sake of maintaining some continuity of description, to throw together my various observations on the formation, as if made at one time, and to connect them with my exploration of Pabba, which took place on the following morning. The rocks of Pabba belong to the upper part of the Lias; while the lower part may be found leaning to the south, towards the Red Sandstones of the Bay of Lucy. Taking what seems to be the natural order, I shall begin with the base of the formation first. In the general indentation of the coast, in the opening of which the island of Pabba lies somewhat like a long green steam-boat at anchor, there is included a smaller indentation, known as the Bay or Cove of Lucy. The central space in the cove is soft and gravelly; but on both its sides it is flanked by low rocks, that stretch out into the sea in long rectilinear lines, like the foundations of dry-stone fences. On the south side the rocks are red; on the north they are of a bluish-gray color; their hues are as distinct as those of the colored patches in a map; and they represent geological periods that lie widely apart. The red rocks we find laid down in most of our maps as Old Red, though I am disposed to regard them as of a much higher antiquity than even that ancient system; while the bluish-gray rocks are decidedly Liasic.[3] The cove between represents a deep ditch-like hollow, which occurs in Skye, both in the interior and on the sea-shore, in the line of boundary betwixt the Red Sandstone and the Lias; and it "seems to have originated," says M'Culloch, "in the decomposition of the exposed parts of the formations at their junction." "Hence," he adds, "from the wearing of the materials at the surface, a cavity has been produced, which becoming subsequently filled with rubbish, and generally covered over with a vegetable soil of unusual depth, effectually prevents a view of the contiguous parts." The first strata exposed on the northern side are the oldest Liasic rocks anywhere seen in Scotland. They are composed chiefly of greenish-colored fissile sandstones and calciferous grits, in which we meet a few fossils, very imperfectly preserved. But the organisms increase as we go on. We see in passing, near a picturesque little cottage,--the only one on the s
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