After finding a way to teach the ship's crew members to understand navigation, Nat, a self-taught mathematician and astronomer in eighteenth-century Salem, Massachusetts, writes down his explanations and compiles them into "The American Practical Navigator," also known as the "Sailors' Bible."

Anyone alive in the eighteenth century would have known that "the longitude problem" was the thorniest scientific dilemma of the day -- and had been for centuries. Lacking the ability to measure their longitude, sailors throughout the great ages of exploration had been literally lost at sea as soon as they lost sight of land. Thousands of lives, and the increasing fortunes of nations, hung on a resolution. The quest for a solution had occupied scientists...

Presents a short biography of African-American surveyor and author, Benjamin Banneker, who helped to survey the land for the U.S. Capitol.