The first Pony Express ride was a race against time, but the mail had to come from New York before the rider could start out. But there was a delay, and the train waiting at Hannibal, Missouri, to carry the mail across the state to St. Joseph, where the Pony Express rider waited, couldn’t start on time. The train’s engineer, Ad Clark, had already been told to try to set a speed record, but now he’d have to do better than ever. Just how fast could he push his locomotive?