The Chicago & North Western was among the first railroads to acquire the "super-power" Berkshire type, receiving twelve locomotives from ALCo's Brooks Works in Dunkirk, New York in 1927. They were similar in design to the Boston & Albany's A-1c class, weighing 397,00 pounds and exerting 67,200 pounds of tractive force (76,160 with booster). They had a 100-square-foot grate area, with 4777 square feet of evaporative heating surface and a superheater surface of 2243 square feet. Cylinder dimensions were 28x30 inches, with boiler pressure set at 240 p.s.i. Having a driver diameter of 63 inches, comparable to those of most Mikado types, these early Berkshires could not develop the "super-power" potential for high-speed running; reportedly the C&NW used its 2-8-4s mostly for coal trains on its southern Illinois extension through Peoria. This undated image of No. 2809, taken at the C&NW's Proviso Yard near Chicago, is ascribed to William S. Kuba of Cedar Rapids, Iowa. No. 2809 met the torch in 1952.