THE TRACTOR PLOW HITCH 177 



law. The damage that is done to both the plow and 

 tractor cannot be estimated, but it should be plainly 

 evident that when the tractor is operating at its max- 

 imum capacity and the rear wheels are sliding toward 

 the furrow wall and the front wheels pointing to the 

 opposite direction on account of the operator trying to 

 keep the plow cutting full width, there must be 

 immense tortional stress on the tractor and tremendous 

 end thrust on both the front and rear axles that cause 

 the tractor to work harder than when the tractor is 

 pulling in a straight line of draft. As a matter of fact, 

 experiments have been made which show an increase of 

 power required from 15 to 25 per cent, to say nothing of 

 the damage done to the plow when the tractor produces 

 enough power to spring the plow out of shape. 



Fig. 6 illustrates for all practical purposes a perfect 

 line of draft through the center of the plow and the 

 center of power on the tractor. The slight distance the 

 tractor is off center will not affect the working of the 

 plow. When the plow and tractor are adjusted to this 

 position the energy of the tractor is directed towards 

 pulling the plow straight ahead. There is no side force 

 of any kind to be overcome in the operation of the plow. 

 Naturally, the minimum power will be required to pull 

 the plow. The plow will do a perfect job. Neither 

 plow nor tractor will be subjected to side stress which 

 causes unnecessary wear, and oftentimes sudden break- 

 age. 



When it is necessary to hitch to one side the tractor 

 has to exert power enough to overcome the forces which 

 operate against this line when it deviates from the center 

 line of draft. This can easily be seen by Fig. 7. C is 

 the center of weight of the plow. A is the center of 



