PIPES AND NOZZLES.
Wronght-Iron Pipes.—Wrought-iron
pipe is used extensively in California on account of its cheapness of
construction, its adaptability for crossing depressions, the facility
with which it can be moved (changes of the position of the line being
often necessary), and other advantages arising from its lightness
combined with great tensile strength.
It is used as—
(i) A water-conduit, replacing ditches and flumes. Where large depressions are crossed it is called an " inverted siphon."
(2) A " supply or feed pipe," conveying water from the " pressure box " to the claim.
(3)
A " distributing pipe," taking the water from the "distributer," or
"gates," at the end of the supply pipe, and delivering it to
(4) the "discharge pipe " or "nozzle."
Large
mining companies often have their pipes constructed at their own
workshops, although generally the iron plates of proper size and
thickness are punched and rolled before delivery, and put together on
the claim.
Inverted Siphons.—According
to Father Secchi, there is near the town of Alatri, in Italy, an "
inverted siphon" with a depression of three hundred and thirty-eight
feet, supposed to have been constructed by the Romans two hundred years
before Christ. The pipes
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