113 



Haul 



The pay haul is equal to the area of the rectangle which has for its 

 base the haul, anrl its altitude the total yardage or maximum ordinate, 

 the product of the two being also the area of the mass diagram. 



If the points are connected by a curved line it will give practically 

 the true result, but if the points of the diagram are connected by straight 

 lines as is recommended by most engineers, and as was done here, it gives 

 values always against the contractor ; on short haul being in error as 

 high as 6 per cent., and on long haul about 1.0 per cent. 



Final summary in tabular form: 



Method. 



Max. Error in 9J. 



[8—18192] 



