Page:Physical Geography of the Sea and its Meteorology.djvu/222

196 by the "brave west winds" of those regions. Hence the icebergs that are so often seen to the south of the Cape of Good Hope. They set off for the Atlantic, but are driven to the eastward by the west winds of these latitudes. The Gulf Stream seldom permits icebergs from Arctic waters to reach the parallel of 40° in the North Atlantic; but I have known the ice-bearing current which passes east of Cape Horn into the South Atlantic to convey its bergs as far as the parallel of 37° south latitude. This is the nearest approach of icebergs to the equator. These currents which run out from the intertropical basin of that immense sea—Indian Ocean—convey along immense volumes of water containing vast quantities of salt, and we know that sea water enough to convey back equal quantities of salt, and salt to keep up supplies for the outgoing currents, must flow into the intertropical regions of the same sea; therefore, if observations were silent upon the subject, reason would teach us to look for currents here that keep in motion immense volumes of water.

395. The currents of the Pacific—drift-wood.—The contrast has been drawn (§391) between the Japan or "Black Stream "of the North Pacific, and the Gulf Stream of the North Atlantic. The course of the former has never been satisfactorily traced out. There is (Plate IX.), along the coast of California and Mexico, a southwardly movement of waters, as there is along the west coast of Africa towards the Cape de Verd Islands. In the open space west of this southwardly set along the African coast there is the famous Sargasso Sea (Plate IX.), which is the general receptacle of the drift-wood and sea-weed of the Atlantic. So, in like manner, to the west from California of this other southwardly set, lies the pool into which the drift-wood and sea-weed of the North Pacific are generally gathered, but in small quantities. The shores of Johnston's Islands (17° N., 169° 30' W.), which are near the edge of this pool, are lined with drift-wood from the Columbia, and the red cedar of California. The immense trees that have been cast up on these guano islands were probably drifted down with the cool California current into the north-east trades, and by them wafted along to the west, thus showing that the currents of the North Pacific flow in a sort of circle, on the outer edge of which lie the Japanese and Aleutian Islands, and the north-west coast of America.

395. The Black Current of the Pacific, like the Gulf Stream, salter than the adjacent waters.—The natives of the Aleutian Islands,