MOTIVE POWER AND ROLLING STOCK 



307 



with truss rods. Two single-cylinder engines are attached to 

 the frame, one on each side of the boiler, and transmit the power 

 directly to a heavy crank shaft, placed under the boiler and at 

 right angles to it. This shaft is held in position by a frame fixed 

 to the boiler, and power from the shaft is transmitted by gearing 

 to a central articulated line shaft which passes to the forward 

 and rear trucks and runs on bearings on top of each truck axle. 

 Pinions fitted on this shaft mesh into gears on each axle and 

 thus transmit power to the driving wheels. 



Locomotives of this class are built in weights ranging from 

 18 to 75 tons. Those of from 18 to 60 tons' weight have eight 

 drivers and those of from 65 to 75 tons weight have twelve 

 drivers. 



A CHmax locomotive with an upright engine and a "T" 

 boiler is built in 15- and 18-ton weights. The frame of heavy 

 timbers is supported at each end by a pair of swivel trucks. 

 Two vertical high-speed, double-acting engines are located in the 

 center of the main frame and are directly connected to a shaft 

 which carries two spur gears of different sizes, which mesh into 

 two main gears on the center driving shaft. These provide a 

 high or low speed as required. A center shaft transmits power 

 to the driving wheels in the same manner as the horizontal style 

 of locomotive previously described. This locomotive is used on 

 stringer and light steel roads. 



The Heisler locomotive is built in weights ranging from 18 

 to 75 tons. The locomotive and tender are carried on a heavy 

 steel frame mounted on two pairs of swivel trucks, one set being 

 placed under the forward end of the locomotive and the other 

 under the tender. 



Power is furnished by two single-cylinder engines attached to 

 the frame one on each side of the boiler. Each is inclined at an 

 angle of 45 degrees from the vertical. The reciprocating parts 

 of the engine are connected directly to a central single-throw, 

 articulated driving shaft. 



Spur wheels are fitted to the center of the forward and the 

 rear axles and pinions attached to each end of the driving shaft 

 mesh into them. The spur wheels and pinions are enclosed in 



