Between voyages, Bowditch published two revisions of Moore's book. By 1801 he had made so many improvements to the original that that an entirely new version was published under his own name. Written specifically so that a sailor with limited education could follow it, Bowditch's The New American Practical Navigator was the first complete and accurate handbook of navigation tables. It provided data on wind speeds and patterns, notes on ocean currents, directions on how to calculate tides, reliable mathematical techniques for fixing locations at sea, a glossary, explanations of rigging, guidance on how to keep a ship's journal, and, of course, extensive instructions on navigation. The London Athenaeum called it the best work of its kind ever published in Britain or the United States.
By the time Bowditch took his last trip to the Indies in 1803, he had attained the rank of captain. But his seafaring days were over. The success of the Practical Navigator won him an invitation to teach at Harvard; later Thomas Jefferson sought him out for the University of Virginia, and West Point was interested, too. Bowditch declined all the offers, preferring to work in business. His position as president of the Essex Fire and Marine Insurance Company gave him the financial security and the time he needed to pursue his other interests.