Ragnarok : the age of fire and gravel

36 THE DRIFT.

the whole strait is blocked up with ice each winter, and the great mass swung bodily up and down, “ grating along the bottom at all depths,” he “found the rocks ground smooth, but ot striated.” * At Cape Charles and Battle Harbor, he reports, “the rocks at the water-line are not triated.”+ At St. Francis Harbor, “the water-line is much rubbed smooth, but not striated.” | At Sea Islands, he says, “No striz are to be seen at the land-wash in these sounds or on open sea-coasts near the present waterline.” *

Again: if these drift-deposits, these vast accumulations of sand, clay, gravel, and bowlders, were caused by a great continental ice-sheet scraping and tearing the rocks on which it rested, and constantly moving toward the sun, then not only would we find, as I have suggested in the case of glaciers, the accumulated masses of rubbish piled up in great windrows or ridges along the lines where the face of the ice-sheet melted, but we would naturally expect that the farther north we went the less we would find of these materials ; in other words, that the ice, advancing southwardly, would sweep the north clear of débris to pile it up in the more southern regions. But this is far from being the case. On the contrary, the great masses of the Drift extend as far north as the land itself. In the remote, barren grounds of North America, we are told by various travelers who have visited those regions, “sand-hills and erraties appear to be as common as in the countries farther south.” || Captain Bach tells us“ that he saw great chains of sand-hills, stretching

* “ 4 Short American Tramp,” pp. 68, 107.

+ Ibid., p. 68. + Ibid., p. 72.

* Tpid., p. 76. | “ The Great Ice Age,” p. 391.

A“ Narrative of Arctic Land Expedition to the Mouth of the Great Bish River,” pp, 140, 346.