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BULLETIN 115, U. S. DEPARTMENT OF AGRICULTURE. 
Suggested design for proportional division box. — The structure 
shown in Plate VII, figure 2, is a very common and very faulty 
type of installation. The division board is set so as to divide the 
check board in the box in the same proportion as the water right of 
the Consumer taking water through the small opening at the left, of 
the box bears to the total water in the ditch. The area of the cross 
sections of the water in the two portions of the box may be propor- 
tional in the correct ratio, but the discharge through each part- of 
the box equals the area multiplied by the velocity, and the latter is 
