Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/200

 nature, and the difficulty which will be found in giving an adequate explanation of its origin.

It is to be observed near Kylehaken, occupying a space of about a mile on the shore, but not exceeding a few hundred yards in breadth, terminating in one side on the elevated ground, as it does in the sea on the other. It seems to be the remains of a plain once much more extensive, since its boundary towards the sea consists of a series of straight lines, the loose materials assuming the usual angle and exhibiting precisely the same appearances which characterize the terraces that line the alluvial vallies through which active rivers have cut their way. The bar of Kylehaken harbour, and the gravelly soundings of this shore, which render it an insecure anchorage, equally indicate an extent once more considerable, and confirm the supposition produced by its straight edge and the angle of its declivity. Its surface is about 60 or 70 feet above the level of the sea.

No rivers at present flow in the vicinity of this plain, nor is there, from the form of the ground, any reason to suppose that they have ever flowed so as to enable us to account for this deposit of loose materials. The substances are nevertheless rounded, and consist of those rocks which are seen in the neighbourhood, presenting a large proportion of the various hard sandstones, with some occasional pebbles of gneiss and of hornblende slate. It might perhaps be imagined that the ordinary fragments of the mountains which back this little plain, descending to the sea and there rolled, might have been rejected by the tides so as to form these banks, but this supposition is invalidated partly by the presence of gneiss and hornblende slate, which do not occur among these mountains, and partly by the altitude of the banks above the present high-water mark. It must doubtless be granted that if at some more ancient