The last steam locomotives ordered by a U.S. railroad for passenger service were the five class L-2a 4-6-4s that Baldwin Locomotive Works delivered to the Chesapeake & Ohio in 1948. They were also the heaviest Hudsons ever built, exceeding the 442,000-pound weight of the earlier L-2 class of 1942. Additionally, they incorporated Franklin rotary poppet valves in the place of the Baker gear of the L-2 class. These 4-6-4s had 78-inch drivers, 25x30-inch cylinders, and 255 p.s.i. of boiler pressure, resulting in a tractive force of 52,100 pounds. For other dimensions see the commentary on No. 311, following. This photo, taken at Cincinnati in September 1950, has been attributed to the Harold Vollrath collection but comes to our Archive via a Flickr site that was discontinued in 2008.