Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/340

 unworn nature of the fragments, and their identity with the rocks above, appears evidently to have resulted from the wearing down of the summits. But the terraces themselves at the top of the glen vary in composition, and though often composed of the same sharp fragments that overspread the general declivity, they occasionally also exhibit various rolled and transported matters. The conoidal hillocks which I have just mentioned, as occurring between Glen Fintec and Glen Glastric, are of a very different composition. Numerous sections of them are to be seen, the result in some cases of a road lately made, in others of the action of water. By these they are shown to consist of deposits of fine sand, gravel, clay, and rolled stones of different sizes, disposed in a manner irregularly stratified, and in a direction more or less horizontal. The terraces and hillocks which occupy positions much inferior to this all the way along the course of the Spean to its entrance into the Lochy, are of the same materials.

I could perceive no traces of any lines on the left hand, from Glen Glastric downwards, for a space of about two miles. No reason for this deficiency appears, either in the form or composition of the ground. On the contrary it possesses that gentleness of slope and curvature, and that uniformity of alluvial surface on which, in the upper parts of the glen, the lines are always most deeply marked. Nor does it give rise to any streams to the action of which their loss and disappearance might be attributed. Were it not that a similar interruption occurs at a lower point down the glen, as well as in the other vallies connected with it, we might at first suppose that the acting cause had here terminated. It is in no respect different from many of the upper parts of the glen on which the roads are marked, except in the gentleness of its slope. Yet this is insufficient to account for the deficiency, as the appearance