Keywords: Big Boy cropped.jpg en Photograph of Union Pacific 4012 Big Boy locomotive STEAM OVER SCRANTON THE LOCOMOTIVES OF STEAMTOWN SPECIAL HISTORY STUDY Steamtown National Historic Site Pennsylvania http //www nps gov/history/history/online_books/steamtown/shs htm Gordon Chappell 1991 Photo taken from STEAM OVER SCRANTON THE LOCOMOTIVES OF STEAMTOWN SPECIAL HISTORY STUDY Steamtown National Historic Site Pennsylvania Author Gordon Chappell National Park Service United States Department of the Interior PD-USGov Union Pacific 4012 |