(MONTANA) Bischoff, A. Map of North- West part of Montana...Great Northern Line St. Paul, Minneapolis & Manitoba Ry. Pacific Extension. Elbridge H. Beckler, Chief Engineer. Helena, Mont. Scale 1 in.= 2 miles. Pen and ink on oil cloth, 27-1/2 x 36". (Map 34)Northern Pacific Railway Company1891 April 6eng