In short, enough northern rock-débris lies upon the low-grounds of northern Europe, which, were it restored to the countries from which it has been taken, would obliterate all the lake-hollows of Finland and Sweden, raise the level of those lands by 80 feet, and fill up the entire basin of the Baltic, with all its bays. And yet this estimate leaves out of account all the material which the ice-sheet carried away from Norway and the British Islands. Of the glaciation of our own land I need say very little. The configuration of our country necessarily made it a centre of dispersion during the Ice Age, and the ice which covered Ireland, Scotland, and the major portion of England radiated outwards from the dominant elevations of the land. But as the ice creeping outwards from those centres became confluent, the directions which it followed were often considerably modified, especially upon the low-grounds. We know that the British ice-sheet not only covered the land up to near the tops of our higher mountains, but filled up all our seas and extended into the Atlantic beyond the coasts of Ireland and the Outer Hebrides--these latter islands having been glaciated from the east by the ice that flowed outwards from the mainland. Another point upon which we are now well assured is the fact that the British and Scandinavian ice-sheets coalesced, so that the basin of the North Sea completely brimmed over with glacier-ice. Finally, then, in contemplating the physical conditions that obtained in northern Europe at the climax of the Ice Age, we have to picture to ourselves the almost total obliteration under a vast ice-sheet of all the land-features of the British Islands, Scandinavia, and Finland, and the adjacent low-lying tracts of Denmark, Holland, Germany, Poland, and Russia. If at that distant date a prehistoric man could have stood on the summit of Snaehatten, he would have seen an apparently interminable plain of snow and ice, bounded only by the visible horizon. Could he have followed the plain southwards in hopes of escaping from it, he would have descended its gently-sloping surface by imperceptible gradations for a distance of 700 miles, before he reached its termination at the foot of the mountains of middle Germany. Or, could he have set out upon an easterly course, he would have crossed the Gulf of Bothnia, buried several thousand feet beneath him, and touched the foot-slopes of the Ural Mountains before he gained the terminal front of the ice-cap, a distance of 1600 miles. On the other hand, had he walked south-west in the direction of Ireland, he would have traversed the area of the North Sea at a height of several thousand feet above its bed, and, crossing the British area, would only have reached the ice-front at a point some 50 miles beyond the coast of Ireland. Here he would have seen the ice-sheet presenting a steep face to the assaults of the Atlantic, and breaking away in massive tabular bergs, like those