Unknown2019-02-042019-02-041955EPM-071-02-010http://hdl.handle.net/20.500.11867/15424Single 17 x 11 inch sheet, bi-folded. Printed recto and verso. Back cover creased down the middle."Northern Pacific Railway's $5,500,000 Push Button Retarder and Freight Classification Yard. Rail Transportation, the important key to the expanding economic activity of the Tri-Cities and the Columbia Basin." Black and white photographs throughout.Railroads--Northern Pacific;