Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1892-01-29
Hydraulic Mining.

Some time ago there was dinner party
at Cen Schofeld's house in Washington.
Among the guests were President Harri-
son, Chief Justice Fuller, the late Secreta-
ry Window, Speaker Reed, Senator Shcr-
man and Senator Sanford, and Mr.. Justice
Stephen J. Field
During the dinner the conversation
turned upon mining operations in Caliior-
mia, and Judge Field, whose knowledge of
all matters relating to the Pacific coast is
as extensive as his powers of narrative are
entertaining, astOnshed the distinguished
company by some of his assertions i'm re-
gard to the force of Jets of water employed
in hydraulic mining. He described the
wonderful manner i'm which the streams
from the hose cut to pieces and tear down
the hills that hold the precious metal
Judge Field cited the Hon. James G.. Fair
as his authority for the statement that I'M
der vertical pressure of one or two hun
dred feet the force of the stream is some
times so great as to hurl away or hold
boulders weighing a thousand pounds and
that it would be no more possible to cut
through such a stream with a crowbar or
an axe, where it issued from the nozzle
than to sever eight inches of solid iron
with penknife.
Il
ator Fair. in a letter asking for expert tes-
timony about the power of water applied
by hydraulic machinery, these assertions
were received by some of Gen. Schofeld's
guests with smiles of polite incredulity
The eminent iurist felt that his position,
for the moment, was somewhat like that
of the Englishman who informed the King
of Siam that in England water often be
came so hard that people could walk on it,
In consequence of this incident, and for
the vindication of his own reputation for
veraclty, Judge Field has collected from
several of the highest authorities on prac-
teal hydraulics evidence and opinions that
are of great interest. Ex-senator Fair
tells Justice Field that at the Spring Val
ley gold mine in Cherokee, California, the
water used in the hydraulic mining opera
tons was brought in pipes and bitches
from distance of nearly one hundred
miles, and that the volume of water used
on every working day in that mine amount
ed to three times the number of gallons
consumed daily by the entire city of San
Francisco.
Mr. Louis Glass for sixteen years the
superintendent of the Spring Valley mine,
assures Justice Field that he has seen an
eight-nch stream, under 81 feet of verti-
cal pressure, move in "A sluggish way two
ton boulder at distance of 20 feet from
the nozzle; and that the same stream strik-
ing rock of 800 pounds would throw it
as a man would throw twenty-pound
weight. "No man that ever lived" adds
Mr.. Louis Glass, "COuld strike a bar
through one of these streams within 20
feet Of discharge; and human being
struck by such a stream would be Killed
pounded into a shapeless mass"
Mr.. Augustus J. Bowie of San Francis
60, the author of a standard book on hy-
drauic mining, estimates that the stream
from a siN-inch nozzle, under $50 feet YER
ticle pressure, delivers a blow of U.s., 49,
foot pounds every second. equivalent to
1910 horse power. at is absolutely i'm
possible says Mr. Bowie. TO cut such
stream with an axe, or to make an impress
sion on il with any other IMPLEMENT
Mr.. Bowie adds that although never to his
knowledge has a man been struck bv such
stream as it comes from the pipe several
accidents have occurred where miners were
killed by very much smaller streams at dis
tances Of $50 to POO feet from the nozzle.
After an elaborate series of computa-
tions, Prof Samuel b. Christy of the Uni
versity of California, an eminent authority
on mining and metallurgy. reports to JUS
tice Field that if nozzle of from six to
nine inches in diameter was specially ar
ranged to throw stream vertically upward
against a spherical boulder of quartz
weighing 1000 pounds, the vertical head
being anywhere from 100 TO 800 feet. the
boulder would he forced up until the d-
mnished velocity of the stream established
an equilibrium of pressures. There would
be point at which the upward pressure of
the stream would exactly balance the gray
ity pressure of the boulder, holding il. the
halt-ton rock, there suspended. In prac-
tice of course, the boulder could not be
balanced accurately upon the axis of the
stream, but would fall to one side or the
other But if a large conical basket of
iron bars was arranged about the nozzle so
as to catch the boulder, whenever it should
be DETECTED from the stream and return il
to the nozzle, the 1000 pounds of quartz
would be kept in play like ball in foun-
tain. As to cutting these streams, Prof.
Christy says that he has often tried to
drive a crowbar into one of them The
stream felt as solid as bar of iron. and,
although he could feel the point of the
crowbar enter the water for perhaps half an
inch, the bar was thrown forward with
such force that it was almost impossible to
retain it in the grasp. An axe swung by
the most powerful man alive could not
penetrate the stream yet it might be cut
by the finger of child, if the child was
seated on "A railway train moving parallel
with the stream in the same direction and
with the same velocity. That velocity
would be considerably more than mile a
minute. -Ne,C York Sun.