On 2 July 1812, Captain David Porter raised a banner on the USS Essex proclaiming 'a free trade and sailors rights', thus creating a political slogan that explained the War of 1812. Free trade demanded the protection of American commerce, while sailors' rights insisted that the British end the impressment of seamen from American ships. Repeated for decades in Congress and in taverns, the slogan reminds us today that the second war with Great Britain was not a mistake. It was a contest for the ideals of the American Revolution bringing together both the high culture of the Enlightenment to establish a new political economy and the low culture of the common folk to assert the equality of humankind. Understanding the War of 1812 and the motto that came to explain it – free trade and sailors' rights – allows us to better comprehend the origins of the American nation.

As the United States grew into an empire in the late nineteenth century, notions like "sea power" derived not only from fleets, bases, and decisive battles but also from a scientific effort to understand and master the ocean environment. Beginning in the early nineteenth century and concluding in the first years of the twentieth, Jason W. Smith tells the story of the rise of the U.S. Navy and the emergence of American ocean empire through its struggle to control nature. In vividly told sketches of exploration, naval officers, war, and, most significantly, the ocean environment, Smith draws together insights from environmental, maritime, military, and naval history, and the history of science and cartography, placing the U.S. Navy's scientific efforts within a broader cultural context. By recasting and deepening our understanding of the U.S. Navy and the United States at sea, Smith brings to the fore the overlooked work of naval hydrographers, surveyors, and cartographers. In the nautical chart's soundings, names, symbols, and embedded narratives, Smith recounts the largely untold story of a young nation looking to extend its power over the boundless sea.

In becoming "a useful man" on the maritime stage, Matthew Fontaine Maury focused on the ills of a clique-ridden Navy, charted sea lanes and bested Great Britain's admiralty in securing the fastest, safest routes to India and Australia. He helped bind the Old and New worlds with the laying of the transatlantic cable, forcefully advocated Southern rights in a troubled union, and preached Manifest Destiny from the Arctic to Cape Horn. And he revolutionized warfare in perfecting electronically detonated mines. Maury's eagerness to go to the public on the questions of the day riled powerful men in business and politics, and the U.S., Confederate and Royal navies. He more than once ran afoul of Jefferson Davis and Stephen R. Mallory, secretary of the Confederate States Navy. But through the political, social and scientific struggles of his time, Maury had his share of powerful allies, like President John Tyler.