DEFINITIONS AND MECHANICAL PRINCIPLES 15 



of the other horse, or placing the center clevis out toward 

 the other horse. The correct division of the load between 

 horses of different sizes is not definitely known, but it is 



Five Horse Tandem. 



FIG. 3 GOOD TYPES OF EVENERS WHICH WILL DIVIDE EQUALLY 

 THE DRAFT 



thought that the division should be made in about the 

 same proportion as each horse's weight is of their com- 

 bined weight. 



28. Inclined plane. The tread power is an example of 

 the utilization of the inclined plane, in which the plane 

 is an endless apron whose motion is transferred to a 

 shaft. The tread power is illustrated in Part II., Farm 

 Motors. 



29. The screw is a combination of the inclined plane 



