68 
BULLETIN 376, U. S. DEPARTMENT OF AGRICULTURE. 
Relative capacities for left slants -j|- ^'~_ 
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Relative capacities for right slants. 
Fig. 6.— Logarithmic diagram showing relative capacities of wood-stave pipe of various diameters for 
any given hydraulic gradient. For instance, an 8-inch pipe will carry one-third as much as a 12-inch 
pipe, and an 18-inch pipe will carry three times as much as a 12-inch pipe. For the first problem, enter 
the diagram at the bottom (as noted) on the left slanting line leading from 12 inches as a base. The inter- 
section of this slant with the vertical line above 8 is approximately on the horizontal line representing 1/3, 
as shown by figures at left of diagram. Similarly for the second problem follow the right slant from 12 
as a base to the intersection of this slant with the vertical line from 18. This intersection is approxi- 
mately on the horizontal line representing 3 as shown by figures at right of diagram. 
