His contribution, A Man with a Gun Lives Here (2010), is based on the secret codes used by hobos as they roamed the country during the Great Depression, but the music in this case is devoid of folk tunes or invocations of particular styles (Snowden’s Appalachian Polaroids, a work featured at last year’s “Fast Forward” festival that incorporated an actual folk tune). Instead, his piece for this disc unfolds naturally from the history and character of vagabond culture.