and with a very slight pitch or slope it would slide forward along the incline.' To this let me add that if the floor on the margin of the heap of grain was undulating the stream of grain would take the course of such undulations. The want, therefore, of much slope in a country and the absence of any great mountain-range are of very little moment to the movement of land-ice, _provided we have snow enough_" On another page Dr. Brown had well said that "the country seems only a circlet of islands separated from one another by deep fiords or straits, and bound together on the landward side by the great ice covering which overlies the whole interior.... No doubt under this ice there lies land, just as it lies under the sea; but nowadays none can be seen, and as an insulating medium it might as well be water." In his recently published volumes descriptive of the journey across the Greenland ice-sheet, alluded to on page 39, Dr. Nansen sums up his inferences in very much the same way: "The ice-sheet rises comparatively abruptly from the sea on both sides, but more especially on the east coast, while its central portion is tolerably flat. On the whole, the gradient decreases the farther one gets into the interior, and the mass thus presents the form of a shield with a surface corrugated by gentle, almost imperceptible, undulations lying more or less north and south, and with its highest point not placed symmetrically, but very decidedly nearer the east coast than the west." From this rapid glance at the existing glaciers of the world we see that a great ice age is not altogether a strange thing in the world. The lands about the south pole and Greenland are each continental in dimensions, and present at the present time accumulations of land-ice so extensive, so deep, and so alive with motion as to prepare our minds for almost anything that may be suggested concerning the glaciated condition of other portions of the earth's surface. The _vera causa_ is sufficient to accomplish anything of which glacialists have ever dreamed. It only remains to enquire what the facts really are and over how great an extent of territory the actual results of glacial action may be found. But we will first direct more particular attention to some of the facts and theories concerning glacial motion. CHAPTER III. GLACIAL MOTION.