Tracks in the Sea captures a rich yet little-known chapter in the history of seafaring - the mapping of the oceans by Matthew Fontaine Maury, the father of modern navigation and ocean science. Voyages in the early 1800s were risky endeavors. Navigation was uncertain. Chronometers were a new technology, and only a few navy ships and wealthy merchant vessels carried them. And route planning was a hit-or-miss affair. Knowledge of prevailing winds and currents had advanced little since Columbus. What lore existed was mostly anecdotal. There were no "highways" on the seas, and hundreds of ships were lost each year. The cost in property and lives was enormous. In eighteen years of sustained and inspired labor starting in 1842, drawing on the logbooks of sailing ships from around the world, Maury changed all that. Driving himself and his staff at the U.S. Naval Observatory with relentless curiosity, ambition, adventurousness, and altruism, he mapped the oceans' great surface currents and wind systems and showed shipmasters how to shave weeks or months from voyages. No less than the invention of the chronometer, the pilot charts and wind and current maps of this self-taught genius from a T