To find the theoretical delivery of pumps, in gallons per stroke.
Set 29·4 on B to the diameter of the plunger in inches on D, and over
length of stroke in feet on B read theoretical delivery in gallons per
stroke on A.
(N.B.—A deduction of from 20 to 40 per cent. should be made to allow for
slip.)
To find loss of head of water in feet due to friction in pipes (Prony’s
rule).
Set diameter of pipe in feet on B to velocity of water in feet per
second on D and bring cursor to 2·25 on B; bring 1 on B to cursor, and
over length of pipe in miles on B, read loss of head of water in feet,
on A.
To find velocity in feet per second, of water in pipes (Blackwell’s
rule).
Set 2·3 on B to diameter of pipe in feet on A, and under inclination of
pipe in feet per mile on B read velocity in feet per second on D.
To find the discharge over weirs in cubic feet per minute and per foot
of width. (Discharge = 214√(_h_^3))
Set 0·00467 on C to the head in feet _h_ on D, and under _h_ on B read
discharge on D.
To find the theoretical velocity of water flowing under a given head in
feet.
Set index of B to head in feet on A, and under 64·4 on B read
theoretical velocity in feet per second on D.