The system of winds and currents in the North Atlantic rotates in a clockwise direction so that, crossing from east to west in the northern part of the ocean, the winds and currents will be predominantly foul. This means that a sailing vessel making her way, for example, from the Channel to New York will be likely to cover a distance something nearer 4000 than the nominal 3000 n. miles—more or less according to her windward ability. Alternatives to the direct route have thus grown up over the years from considerations as to which 4000 miles or so is likely to prove the most advantageous and swift. An earlier paper gave an account of the generally accepted routes and the principal sources from which they have been derived.