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402 enters the Atlantic around Cape Horn, and changes into warm again as it enters the Gulf of Guinea. It was owing to this great southern flow from the coral regions that Captain Ross was enabled to penetrate so much farther south than Captain Wilkes on his voyage to the Antarctic. The North Pacific, except in the narrow passage between Asia and America, is closed to the escape of these warm waters into the Arctic Ocean. The only outlet for them is to the south. They go down towards the antarctic regions to dispense their heat and get cool; and the cold of the Antarctic, therefore, it may be inferred, is not so bitter as is the extreme cold of the Frozen Ocean of the north.

749. Ditto from the Indian Ocean.—The warm flow to the south from the middle of the Indian Ocean is remarkable. Masters who return their abstract logs to me mention sea-weed, which I suppose to be brought down by this current, as far as 45° south. There, it is generally, but not always, about 5 degrees warmer than the ocean along the same parallel on either side.

750. A wide current.—But the most unexpected discovery of all is that of the warm flow along the west coast of South Africa, its junction with the Lagulhas current, called, higher up, the Mozambique, and then their starting off as one stream to the southward. The prevalent opinion used to be that the Lagulhas current, which has its genesis in the Red Sea (§ 390), doubled the Cape of Good Hope, and then joined the great equatorial current of the Atlantic to feed the Gulf Stream. But my excellent friend, Lieutenant Marin Jansen, of the Dutch Navy, suggested that this was probably not the case. This induced a special investigation, and I found as he suggested, and as is represented on Plate IX. Captain N. B. Grant, in the admirably well-kept abstract log of his voyage from New York to Australia, found this current remarkably developed. He was astonished at the temperature of its waters, and did not know how to account for such a body of warm water in such a place. Being in longitude 14° east, and latitude 39° south, he thus writes in his abstract log: "That there is a current setting to the eastward across the South Atlantic and Indian Oceans is, I believe, admitted by all navigators. The prevailing westerly winds seem to offer a sufficient reason for the existence of such a current, and the almost constant south-west swell would naturally give it a northerly direction. But why the water should be warmer here (38° 40′ south) than between the parallels of 35° and 37° south, is a