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 hardships, he approached Europe for the final leg. He never made it. His mysterious disappearance in eastern Turkey sparked an international outcry and compelled Outing to send William Sachtleben, another larger-than-life cyclist, on Lenz's trail. Bringing to light a wealth of information, Herlihy's gripping narrative captures the soaring joys and constant dangers accompanying the bicycle adventurer in the days before paved roads and automobiles. This untold story culminates with Sachtleben's heroic effort to bring Lenz's accused murderers to justice, even as troubled Turkey teetered on the edge of collapse.   DAVID V. HERLIHY is the author of Bicycle: The History and his work has been featured on National Public Radio and Voice of America and in the New York Times, the Boston Globe, Boston, and Historic Preservation. In 1999 Herlihy received the McNair History Award from the Wheelmen, the preeminent American association of antique bicycle collectors.