The Manitowoc tribune. [volume] (Manitowoc, Wis.) 1866-1878, 1876-10-26
HYDRAULIC MINING At DUTCH
FLAT.

The method of hydraulic mining Is
briefly this From some lofty point a
head of water is let on through iron
pipes of varying diameter, and is pro-
jected in thin stream against the bot
tom of hill of gravel known to contain
gold. The earth falls in 1oosened mas
ses, and is washed into channels which
lead to sluice- boxes. A sluice-box is a
narrow trough made of planks and pro-
vided with false bottom. Over the
upper surface the current Of earth and
water passes, the finer portions of the
gravel, together with what gold there
may be. falling through apertures, upon
the real bottom below. Here at inter-
walls are cross pieces few inches high,
in whose angles quicksilver is placed.
The particles of gold, great and small,
draw to this, while the worthless earth
is washed on and out of the way. These
sluice-boxes are watched night and day.
and are ''cleaned up" thai is, the ANAL
gam is taken out at intervals, which
vary from ten days to three months OF
more, just as the earth is more CIR less
rich In metal.
The pipes which convey the water are
made of thin iron, hardly thicker than
box cardboard, and vary from some forty
: to fifteen inches n diameter. They are
smooth, round and black as jet. They
are laid across depressions in the ground
upon trestles, and where the surface Is
favorable, they are laid upon sleepers
like the tracks of a railway. They are
often miles in length, and though their
general tendency is downward, yet they
make many rises and turns. The pipe
near by you disappears short distance
off, behind low hillock it comes into
view again two or three rods further on;
then it is lost for q quarter of mile,
and you see it climbing hill like
serpent, bending itself over the crest,
and vanishing once more then, perhaps
you may see it in the faint distance curry
ing like a hair-hne, still doing its ire
mendous duty, yet with so little sugges-
tion of the great power contained with
in it.
You bend down and apply your ear to
little orifice you find upon the upper
side of one Of these pipes, and you hear
the furious rush of the water ut The
same time your hat is blown from your
head by back-handed current of air
that bursts from it's Imprisonment with
in the tube. A mile further on you may
be startled to hear a loud continuous
roaring and Kissing. You look about
and discover another Of these pipes sur
charged with water, which seeks to es-
cape from every joint and pin-hole in
the entire length. The ground is wet
beneath it, little pools forming here and
there, while jets Of spray shoot in all
directions, catching the rays of the sun
most delicately.
The water issues from the pipes at the
place where the mining is carried on
with astonishing force. Lofty hills,
broad plains and long cliffs are washed
away, and their ruin completed by moth
ing else than shaft of water a few inches
in diameter, thrown violently and per-
sistently against them. Nothing can
withstand it. Trees, snarled stumps,
rocks of prodigious size, are whirled
hither and thither, like bubbles in the
wind, and the softer earth is melted like
frost before the fire. A stream having
a fall of two hundred feet, and being
forced through two-inch pipe at its
head, is weapon of appalling force.
1t will cut into banks Of packed clay
that pickax cannot penetrate, and tear
out of their Businesses rocks half as large
as a railway car and whirl them about
as easily as garden-jet does its silver
globe. Were it to strike man it would
literally tear him to pieces not stun
him, or simply kill him with the shock
and the suffocation, but it would rend
him limb from limb, as an explosion
would.