The Canadian National Railway system owned more 4-8-4s than any other railroad; counting those on the Grand Trunk and Grand Trunk Western, they totaled 203 engines. In honor of the formation of Canada they were called Confederation types. (Many U.S. railroads called them Northerns, but some used distinctive regional names such as Dixie, Greenbrier, Niagara, Pocono and Wyoming.) No. 6155, shown here taking on water in a photo of unknown origin, belonged to the CNR's U-2-c class outshopped by Montreal Locomotive Works in 1929.

These dual-service locomotives developed 56,785 pounds of tractive effort and weighed 383,000 pounds. They had 25½x30-inch cylinders, 73-inch drivers, and 250 pounds per square inch of boiler pressure. Like many of Canadian National's modern steam engines, No. 6155 sports an Elesco feedwater heater ahead of the stack, an outboard-journal pilot truck, and a Vanderbilt tender. No. 6155 has a Baker valve gear, but later CNR designs favored the simpler Walschaerts gear.