Baldwin Locomotive Works delivered the Burlington’s fifteen class O-4 2-8-2s in 1919, based on the USRA heavy Mikado design. They had the usual Mikado 63-inch drivers and cylinder dimensions of 27x32 inches, and carried 200 p.s.i. of boiler pressure. Weighing 320,000 pounds, they developed a tractive force of 62,949 pounds. Grate area measured 70 square feet, and they had 4291 square feet of evaporative heating surface and 993 square feet of superheater surface. Delivered as coal-burners, they were converted to oil burning and assigned to the CB&Q’s western lines. In 1957, six of these engines (including No. 5506 shown here) were sold to the Burlington’s subsidiary Colorado & Southern. Apparently they were already operating on the C&S and its partner railroad, the Fort Worth & Denver, since No. 5506 (which apparently took the C&S number 804) appears here at Wichita Falls, Texas, on the FW&D, in October 1956. The photographer is not specified, but the photo, from an eBay seller, was included in the Harold Vollrath collection and also appears in the ABPR Archive uploaded by Bud Laws. Retirement for all in this group came in 1960, very late in the steam era.