Page:Physical Geography of the Sea and its Meteorology.djvu/382

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PHYSICAL GEOGRAPHY OF THE SKA, AND ITS METEOROLOGY.

the upper regions, from the equatorial side, where the cross section between any two given meridians is the larger; and this upper current, while on its way from the equator, is continually parting with the heat which it received at and near the surface, and which caused it to rise under the equatorial cloud-ring. In this process it is gradually contracted, thus causing the upper surface of the air to be a sort of double inclined plane, descending from the equator and from the poles to the place of the tropical calm belts.

663. Winds in the southern stronger than winds in the northern hemisphere.—Observations show that the mean weight of the barometer in high southern is much less (Plate I.) than it is in corresponding high northern latitudes; consequently, we should expect that the polar-bound winds would be much more marked on the polar side of 40° S., than they are on the polar side of 40° N. Accordingly, observations (Plate XV.) show such to be the case; and they moreover show that the polar-bound winds of the southern are much fresher than those of the northern hemisphere.

664. The waves and gales off the Cape of Good Hope.—To appreciate the force and volume of these polar-bound winds in the southern hemisphere, it is necessary that one should "run them down" in that waste of waters beyond the parallel of 40° S., where "the winds howl and the seas roar." The billows there lift themselves up in long ridges with deep hollows between them. They run high and fast, tossing their white caps aloft in the air, looking like the green hills of a rolling prairie capped with snow, and chasing each other in sport. Still, their march is stately and their roll majestic. The scenery among them is grand, and the Australian-bound trader, after doubling the Cape of Good Hope, finds herself followed for weeks at a time by these magnificent rolling swells, driven and lashed by the "brave west winds" most furiously. A sailor's bride, performing this voyage with her gallant husband, thus alludes in her "Abstract log" to these rolling seas: "We had some magnificent gales off the Cape, when the colouring of the waves, the transition from gray to clear brilliant green, with the milky-white foam, struck me as most exquisite. And then in rough weather the moral picture is so fine, the calmness and activity required is such an exhibition of the power of mind over the elements, that I admired the sailors fully as much as the sea,