|Butte Anaconda & Pacific Railway Alco-GE 64 and 55 at Rocker, Montana on October 10, 1958, Kodachrome by unknown photographer, Chuck Zeiler collection. Information about these locomotives is a little hard to come by, but here's what I found so far, from the Electric Railway Journal May 31, 1913, verbatim including spelling:
The initial equipment consists of 17 units, 15 for freight and two for passenger service. Each unit weighs approximately 80 tons. The two units forming a freight locomotive in each case will be coupled together and operated in multiple, and combination locomotives will haul the 3400 ton train at a maximum speed of 15 m.p.h against the ruling grade and at 21 m.p.h on level tangent track. The passenger locomotives are the same design as the freight locomotives except they are geared for a maximum of 45 m.p.h. on level tangent track. A schedule of eight passenger trains per day, four each way, is maintained, the average train being composed of a locomotive and three standard passenger coaches. All locomotive equipment, as well as the substation apparatus and overhead line material, was designed and built by the General Electric Company. One of the locomotives will be exhibited at the Master Mechanics' and Master Car Builders' conventions in Atlantic City. The general design is of the articulated double-truck type, all weight being on the drivers. The cab, containing the Engineer's compartment in each end and a central compartment for the control apparatus, is carried by the two truck frames on center pins. It is of the box type, extending the entire length of the locomotive, and is provided with end and side doors. Friction draft gear mounted on the outer end frame of each truck transmits the hauling and buffing stresses directly through the truck frame, diverting these strains from the center pins and underframe. The trucks are built of heavy steel castings. The side frames are of a truss pattern with heavy top and bottom members and pedestal tie bars. They are connected by end frames and a cast-steel center transom. The entire weight is carried on semi-elliptic springs suitably equilized. On each axle is mounted a motor of the twin-geared type. The cab underframe conists of two 12 inch longitudinal steel channels on either side of the center and two six inch X six inch steel angles along the outer edge. The central channels are inclosed and form a distributing air duct for forced ventilation. Air is conducted through the center pins, which are hollow, into the truck transoms and thence to the motors. The Engineer's compartment, at either end of the cab, contains the operator's seat, controller, air-brake valves, bell and whisle ropes, ammeter, air gages, sanders, and other control appartus that should be within immediate reach of the Engineer.