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.
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.
The Sou'-wester
We have to study four regions of one great Sou'-wester wind, which is known to navigators as the South-west Counter-Trade.
WESTERN REGION. The tropic sunshine lifts masses of hot, tremulous vapour from the surface of the Equatorial Pacific. This vapour lifts to a great height and there condenses into clouds. The clouds are swept by the south-west wind and form their floor at a height above the sea of about two miles. The Rocky Mountains reach up bare and stony hands to clutch at the flying moisture and bring down whirling snowstorms. On sweep the cloud fleets across the Canadian Plains with rarely a drop of rain to spare through the summer for the thirsting grass beneath. But slowly the cloud-floor slopes downward until at last the cloud-fleets come to ground, and the breath of the sou'-wester becomes visible as the Northern Forest. Beyond that forest the wind trails its cold vapours over the sub-Arctic tundras of North-Eastern Canada, lashing bleak rains on Baffin's Bay, to spend the last of its moisture in the form of snow upon the Greenland Ice-cap.
Central region
CENTRAL REGION. From the eastern part of the Equatorial Pacific, about the neighbourhood of the Gallipagoes, a second echelon of the sou'-wester brings its immense load of flying clouds high in the air across the United States to slant down out of the skies and brush the Atlantic in the Forties. Strong gales trail their clouds along the Gulf Stream, taking a deal of warmth out of that current. Exposed trees in North-western Europe are slightly bent by the stress of Atlantic gales, while all the trailing clouds discharge their cargoes of warm rain across the Baltic Region. The British Isles, for example, get an annual ration amounting to thirty cubic miles of water fresh from the Equatorial Pacific.