In the late 1880s, Frank Lenz of Pittsburgh, a renowned high-wheel racer and long-distance tourist, dreamed of cycling around the world. He finally got his chance by recasting himself as a champion of the downsized safety-bicycle with inflatable tires, the forerunner of the modern road bike that was about to become wildly popular. In the spring of 1892 he quit his accounting job and gamely set out west to cover twenty thousand miles over three continents as a correspondent for Outing magazine. Two years later, after having survived countless near disasters and unimaginable...