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, comes from a Flickr site that was dropped in 2008. It also appears, attributed to the Harold Vollrath collection, in the ABPR Archive, provided by Bud Laws.