St. Louis Southwestern 4-4-2 601 was one of six Class E-1 4-4-2 Atlantics built by Baldwin in 1909. They were distinctive in that they were built with narrow fireboxes, small drivers, and slide valves, unusual in locomotives with trailing wheels. They had 70" drivers. 21 x 26 inch cylinders, boiler pressure of 185 lbs, and were capable of 25,758 lbs of tractive effort. She was built with slide valves and Stephenson gear, but was later upgraded with larger piston valves, superheaters, and Walschaerts valve gear. SSW 601 was scrapped in 1952. This image from my collection was taken in Shreveport, Louisiana on May 4, 1950.