[Footnote 61: Washington's correspondence was voluminous, and on the subjects relating to climate, agriculture, and internal improvements, he wrote with interest and ability. The letter to Sinclair is characteristic.] * * * * * =_Matthew F. Maury,[62] 1806-1873._= From "The Physical Geography of the Sea." =_250._= THE MARINER'S GUIDE ACROSS THE DEEP. So to shape the course on voyages as to make the most of the winds and currents at sea, is the perfection of the navigator's art. How the winds blow, and the currents flow, along this route or that, is no longer matter of opinion or subject of speculation, but it is a matter of certainty determined by actual observation.... The winds and the weather daily encountered by hundreds who have sailed on the same voyage before him, and "the distance made good" by each one from day to day, have been tabulated in a work called Sailing Directions, and they are so arranged that he may daily see how much he is ahead of time, or how far he is behind time; nay, his path has been literally blazed through the winds for him on the sea; mile-posts have been set up on the waves, and finger-boards planted, and time-tables furnished for the trackless waste, by which the ship-master, on his first voyage to any port, may know as well as the most experienced trader whether he be in the right road or no. ... The route that affords the bravest winds, the fairest sweep, and the fastest running to be found among ships, is the route to and from Australia. But the route which most tries a ship's prowess is the outward-bound voyage to California. The voyage to Australia and back, carries the clipper ship along a route which, for more than three hundred degrees of longitude, runs with the "brave west winds" of the southern hemisphere. With these winds alone, and with their bounding seas which follow fast, the modern clipper, without auxiliary power, has accomplished a greater distance in a day than any sea-steamer has ever been known to reach. With these fine winds and heaving seas, those ships have performed their voyages of circumnavigation in sixty days. [Footnote 62: Formerly an officer of the navy, eminent for his scientific researches and writings on maritime subjects; a native of Virginia.] * * * * * =_251._= THE GULF STREAM.