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.