was encountered than could be hoisted out in the
"skips" with the dirt. At the 2,200 level two Cornish pumps, each with
columns fifteen inches in diameter, were put in. At the 2,400 level
the same pumps were used. On this level a drift was run that connected
with the old Hale & Norcross and Savage shafts, producing a good
circulation of air both in the shaft and in the mines mentioned. At
this point, on account of the inflow from the mines consequent upon
connecting with them by means of the drift, they had more water than
the Cornish pumps could handle, and introduced the hydraulic pumps,
which pumps are run by the pressure of water from the surface through
a pipe running down from the top of the shaft, whereas the Cornish
pumps are run by huge steam engines.
By means of the hydraulic pumps they were enabled to sink the shaft to
the 2,600 level, and extended the Cornish pumps to that point, where
another set of hydraulic pumps was put in. They then sunk the shaft to
the 2,800 level, when they ran another drift westward, and tapped the
vein. The prospects at this depth in the Hale & Norcross and Chollar
mines were so encouraging that the management decided to sink the
shaft to the depth of 3,000 ft. On reaching the 3,000 level, they ran
a third drift through to the vein. The distance from the shaft to the
east wall of the vein was found to be only 250 ft. At the depth of
3,000 ft. they put in one of the pair of hydraulic pumps that is to be
set up there. The second pump is now arriving from San Francisco, and
as soon as the several parts are on the ground, it will be at once put
in place alongside its fellow on the 3,000 level. This additional pump
will increase the capacity from 600,000 to 700,000 gallons in
twenty-four hours, or about forty-five miners' inches.
Owing to the excellent showing of ore obtained on the 3,000 level by
the Hale & Norcross Company, and to the continuation of the ore below
that level (as shown by a winze sunk in the vein), the management
determined to sink the shaft to the vertical depth of 3,200 ft. It is
now 3,120 ft. deep, and it is safe to say that it will reach the depth
of 3,200 ft. early in September, when it will lack but eighty feet of
being as deep as the shaft at Przibram was at the time of the great
festival. Although the shaft is of great size--about thirty feet by
ten feet before the timbers are put in--the workmen lower it at the
rate of about three feet a day, in rock as har
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