314 



POWER AND THE PLOW 



HAULING 



Theoretical Capacity of Tractors on Grades 



Assumed: Tractors delivering at all times exactly the brake 

 h.p. which will produce the rated drawbar horsepower on the 

 level; ground resistance uniform, at 160 Ibs. per gross ton 

 of load and wagon; increase of resistance due to grade 20 Ibs. 

 per ton for each 1 per cent; no slippage, speed constant. No 

 account taken of overload capacity of tractor, all of which would 

 be exerted on the load, with marked increase in amount hauled 

 This table is merely to show the loss due to grades which in- 

 crease the draft of load and decrease the power of the tractor. 



