Baltimore and Ohio Class N-1 -  The Baltimore and Ohio Railroad's sole Class N-1 steam locomotive #5600 George H. Emerson was the first duplex locomotive and the first 4-4-4-4 locomotive ever built. It was designed and built by the railroad's own shops in 1937. The rear set of cylinders were placed beside the firebox. This allowed the locomotive's wheelbase to remain the same. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
Answer:
Mean Of Transportation