It has been my good fortune to make a series of voyages to Bering Sea and Norway in the winter, and in summer along the flanks of both the St. Elias and the Greenland ice-caps. In these journeys by sail and steam, in boats, in canoes, with many landings and scrambles across county, I was able to test the theories of Glacialogists against the actual facts of the Great Ice Age. The Croll theory makes the orbit of the Earth to change at regular intervals into a long ellipse. By roasting one entire hemisphere it provides vapour to cover the whole of the other hemisphere with snows which do not melt. Evidence is scratched up and made the most of for previous ice ages. An imaginary series of cosmic cataclysms is invoked to explain one merely local unpleasantness. Another theory sinks Central America--politically quite a good idea--and throws the Gulf Stream into the Pacific, leaving the North Atlantic to be frozen. It does not explain the American lobe of the icefield which brushed the foothills of the Rocky Mountains in a region outside the influence of the Gulf Stream. {17} It was never the business of Glacialogists to notice that under the inland ice and the great lava floods of Greenland lie pressed magnolia leaves in the high Arctic. These tell me of cloudy skies saving the summer's warmth all through the polar night, of a vast cloud sphere sheltering the whole Earth from a sun much hotter than we know to-day. The Ice Age to me is an incident in that clearing of the skies which dried the world-forest, made the grass steppes and deserts, and evolved the horse. [Sidenote: The Ice-field to-day] The Glacialogists make the Ice Age an episode of the past. Without the slightest relevance to any obliquity of the Orbit, or vagaries of the Gulf Stream, the Ice-cap persists to-day as a living fact. I have been there, have seen it, and cannot be persuaded otherwise. The forces which created the Ice-cap are still at work, and as they merely strengthen or relax, the Icefield grows or shrinks. These forces made the Ice flood to plough the fields and train the folk for seeding a crop of human empires--British, American, Russian, and German world-powers. The ice which prepared town-sites for Moscow, Petrograd, Berlin, London, and New York, may come again to sweep them all away. We are not behaving ourselves so very nicely. {18} I have no theory as to what forces enlarged or contracted the ice flood. The theme of this study is the horse, a creature of grass and water constructed by the forces in sunshine and fresh air, and coloured by the skies. To the skies we must look if we would trace his origin, to the mechanism of the Ice-cap if we would know how his varieties were specialized out of the general type. So let us have a look at the machinery which made and maintains the Ice-cap. PART III. THE SOU'-WESTER. [Sidenote: The Sou'-wester]