The mean velocity of the chief currents in the Azorian Atlantic can scarcely be estimated at much more than two-thirds of a mile per hour, or one-fortieth of that of the winds above them. In the eastern section of the main eastern current the movement varies from 15 to 18 miles in the twenty-four hours. In the central parts of the basin, and especially in the Sargasso Sea, the speed slackens, but again increases near the coast and in the straits between the archipelagoes. Although weak, the movement of the "trade waters," aided by the corresponding winds, is
none the less of great aid to vessels bound for the New World, and but for these favourable conditions Columbus would certainly never have reached Guanahani. Thanks also to these currents, sailing vessels have often reached America when their crews were endeavouring to gain the islands or penetrate into the South Atlantic waters. Nothing is more probable than that in remote times ships were thus turned from their course, and that Phœnicians, for instance, or other involuntary immigrants from the Old World, founded colonies in America. At the
