OF PLACER-MINING IN CALIFORNIA. 49
labor,
used a stream of water under pressure. For this purpose water was
conveyed to the claim in rawhide hose and discharged through a wooden
nozzle against a bank. Torn by the water, the earth was carried into
the sluices and shovelling was thus avoided. A large saving in the cost
of mining was effected, a greater amount of material being washed in a
shorter time. This was the first step in hydraulic mining.
Canvas Hose.—
Mattison's experiments were immediately appreciated and his method
adopted. Hose made of canvas was widely used, the canvas being
strengthened by netting and bound with rope.
Iron Pipe.—Towards
the end of 1853 pipes made of light sheet iron were introduced as a
substitute for canvas hose. The first iron pipe was used by R. R.
Craig, on American Hill, Nevada County. It consisted of about one
hundred feet of stove-pipe. In 1856 a firm in San Francisco commenced
the manufacture of wrought iron pipes for hydraulic mining, and during
the years 1856 and 1857 a large sheet-iron pipe forty inches in
diameter was laid for a water-conduit across a depression at Timbuctoo,
in Yuba County.
Inverted Siphons. —
In 1869 a wire suspension bridge across the Trinity River, near
McGillivray's, was constructed by Joseph McGillivray. This bridge
supported a fifteen-inch wrought-iron pipe which conducted water from
a ditch situated at an elevation of about two hundred and forty feet
above the bridge. The length of the pipe was nineteen hundred and
eighty feet, and the outlet was one hundred and thirty-three feet below
the level of the inlet. In the fall of 1870 the Spring Valley Company,
of Cherokee, Butte County, laid the first large " inverted siphon " in
the mining regions. The siphon was made of wrought iron, riveted. It
was thirty inches in diameter and fourteen thousand feet long, crossing
a depression of nearly one thousand feet.
Improved Nozzles.—With the substitution of sheet-
