74 



THE WHEAT INDUSTRY 



the horses soon become warm and tired. It is 

 easily seen that horse power can not hold its 

 place in competition with the steam engine. 



The most generally used power for wheat 

 threshing is now furnished by steam traction 

 engines. These are built in sizes ranging from 

 six to sixty horse power. They use straw, wood, 



FIG. 45. Pitching bundles into self-feeder on the threshing machine. 



or coal as fuel, coal being by far most common. 

 The advantages of the traction engine are : de- 

 pendability for long hours of continuous oper- 

 ation ; the readiness with which the proper rate 

 of motion may be maintained ; economy, - - it 

 being a cheaper source of power than horses ; and 

 its adaptability to quick change of location. 

 Often it requires not more than five or ten min- 



