On the Last Stage of the Glacial Period in North Britain

Abstract

Conclusion This last phase of the Glacial period was therefore no time of mere local glaciers lingering among some of the higher mountains, but the return of a great ice-sheet which spread over nearly the whole of Scotland and Ireland and also the greater part of England. But the ice seems not to have been so thick and extensive as it was in the early glaciation—nor so enduring; for it has failed to destroy all the beds of clay and sand containing arctic shells which the sea left behind it, whereas in Scotland we find that the ice of the former period cleaned off every thing down to the hard rock. I would suppose that all the mountain-ranges of Scotland and Wales were coated with thick ice, which reached the coast in most places, likewise the hilly ground of the north of England, including the Pennine ridge along its whole length as far at least as Derby. In the lower districts of England further south, there would probably be extensive snow-beds, more or less converted into ice at the bottom. During the summer thaws these would send out great streams of muddy water, occasioning those superficial deposits of brick-earth, warp, and loess which are so widely spread to the southward. Beds of gravel would be lodged where the force of the current was stronger, and when the thaw was unusually rapid. That there must have been heavy beds of consolidated snow even in the extreme south of England, I infer from the fact that I find traces of such in my own neighbourhood, in the low eastern part of Aberdeenshire, on the flanks of hills only a few hundred feet in height. In the low ground in front of these places there is generally a land-locked hollow or shallow basin occupied by peat.