_on the surface_"; and he even thinks that the great mammals, the mammoth and the woolly rhinoceros, "may have survived in Northern Asia down to a comparatively recent date,"[1] ages after they were crushed out of existence by the Drift of Europe and America. Mr. Geikie seeks to account for this extraordinary state of things by supposing that the climate of Siberia was, during the Glacial age, too dry to furnish snow to make the ice-sheet. But when it is remembered that there was moisture enough, we are told, in Northern Europe and America at that time to form a layer of ice from _one to three miles in thickness_, it would certainly seem that enough ought to have blown across the eastern line of European Russia to give Siberia a fair share of ice and Drift. The explanation is more extraordinary than the thing it explains. One third of the water of all the oceans must have been carried up, and was circulating around in the air, to descend upon the earth in rain and snow, and yet none of it fell on Northern Asia! And as the line of the continents separating Europe and Asia had not yet been established, it can not be supposed that the Drift ref used to enter Asia out of respect to the geographical lines. But not alone is the Drift absent from Siberia, and, probably, all Asia; it does not extend even over all Europe. Louis Figuier says that the traces of glacial action "are observed in all the north of Europe, in Russia, Iceland, Norway, Prussia, the British Islands, part of Germany in the north, and even in some parts of the south of Spain."[2] M. Edouard Collomb finds only a "a shred" of the glacial evidences in France, and thinks they were _absent from part of Russia!_ [1. "The Great Ice Age," p. 461. 2. "The World before the Deluge," p. 451.] {p. 31} And, even in North America, the Drift is not found everywhere. There is a remarkable region, embracing a large area in Wisconsin, Iowa, and Minnesota, which Professor J. D. Whitney[1] calls "the driftless region," in which no drift, no clays, no gravel, no rock strive or furrows are found. The rock-surfaces have not been ground down and polished. "This is the more remarkable," says Geikie, "seeing that the regions to the north, west, east, and south are all more or less deeply covered with drift-deposits."[2] And, in this region, as in Siberia, the remains of the large, extinct mammalia are found imbedded in the surface-wash, or in cracks or crevices of the limestone. If the Drift of North America was due to the ice-sheet, why is there no drift-deposit in "the driftless region" of the Northwestern States of America? Surely this region must have been as cold as Illinois, Ohio, etc. It is now the coldest part of the Union. Why should the ice have left this oasis, and refused to form on it? Or why, if it did form on it, did it refuse to tear up the rock-surfaces and form Drift?