A surprisingly elegant mural depicting Mark Twain on the facade of a gas station in Hannibal, a city along the Mississippi River in northeast Missouri, so famous as the boyhood home of the legendary writer and wit, later called "the Father of American Literature" by fellow author William Faulkner, where images, signs, and stories of Twain, born Samuel Langhorne Clemens, can be found on what seems like every block in town