On the Silurian Beds of the Pentland Hills. Part II

On the 21st February 1867, we had the pleasure of laying before the Society the result of our labours in this locality during the summer of 1866;* and, as our conclusions differed somewhat from those of other observers, it may not be considered out of place to give a short résumé of our last paper, the better to connect the conclusions we then arrived at with those which we now propose to lay before you as the results of our farther investigations in the district. Line of Section No. 1 (general and detailed) on Plate.—It may be remembered that our former paper treated, for the most part, of that patch of the Silurian crossed by the North Esk, from near its source at the foot of the East Cairn Hills, to some distance below the reservoir, and that we gave it as our opinion that this section (Section No. 1 on Plate) comprised nearly all the lowest beds of the Silurian formation found in the Pentland Hills. Starting from Carlops, and taking our course up the North Esk, we pass over a vast thickness of coarse conglomerates and gritty sandstones (the ‶Upper Old Red Sandstone″ of the Geological Survey), dipping to the south-east at angles from 30° to 60°, and continuing for nearly a mile; and although we are ascending the bed of the stream, we are actually descending in the series, until we come upon the Silurian rocks, dipping at high angles to the north-west. The order is now