The record-union., 1899-02-12
TO MINE THE RIVER SANDS.
INAUGURATION OF AN IMPORT
ANT ENTERPRISE.
Launching of a Mammoth Mining
Dredger Near Folsom
Yesterday.

"A large number of people-men, wo-
men and .children-from Folsom, Or
angevale and Fair Oaks, with a few
from Sacramento, yesterday gathered
at Mississippi Bar, on the American
River, about four miles this side OF
Folsom, to witness the, launching of the
big dredger that is to be utilized IN
mining the benches of gold bearing
gravel along that stream.
Many supposed the dredger was to
be launched in the river, and that 1t
was the sand or gravel in the channel
that was to be worked. Imagine their
surprise when they found the dredger
on dry land quarter of mile from
the river channel, with only a water
hole alongside of it of about twice the
size of the barge.
This hole was filled with water from
Cox & Clark's north fork ditch. The
excavation was right at the foot of
the high bluff on the north side of the
river and contained about six feet of
water, enough to float the barge read
lily, which is all that is required, as
the water used for washing the gravel
Con the barge) will flow back into the
excavation and thus assist in floating
the barge. The ditch supply can be
called on, however, as fast as there is
any diminution in the volume of water.
The dredger complete consists of the
barge, bucket-dredging apparatus
and machinery for washing the gravel
and saving the gold. Indeed, the en-
tire process of raising the gravel and
extracting the gold is done on the
haTfya Tho ho1 oh ~ a.
lively new one ON this coast, has been
in successful operation in Australia,
and where it can be utilized it is the
cheapest and most economical system
of gold mining known. 1t cannot be
conducted, of course, without water,
and what would be an excess of water
under ordinary placer mining condi-
tions would in no way interfere with
the operation of this dredger.
The machine starts out, for instance,
in a hole filed with water. BY the oper-
alton of its endless-chain bucket sys-
tenn it not only dredges to the required
depth but cuts it's own channel through
the ground that is to be mined, clean
Ing it up as it goes along. Each bucket
full of earth that is taken from in front
or or beneath the dredger is deposited
IN the rear as fast as the gold is washed
from it, so that after mining out any
given area no excavation remains ex-
cept the hole in which the dredger
floats.
The capacity of the dredger is 1000
cubic yards of gravel or material per
day, at an expense of about 6 cents
per cubic yard Careful examinations
of the gravel deposit on Mississippi
Bar show that it will yield 1S cents per
cubic yard, leaving profit of two
thirds of the gross yield Should richer
deposits be found the profits would be
proportionately greater, as the cost of
operating the dredger would remain
the same.
Robert H. Postlethwaite, an expert
enced mining engineer of San Fran
cisco, has superintended the construc-
ton of the dredger at Mississippi Bar,
and the machinery is being supplied
by the Risdon Iron Works of that city,
whose engineer. S.-W. Griffin is on the
ground to put it in position. From
these gentlemen the Record Union's'
representative gathered the facts
stated above. also that the dredger will
be operated by 60-horse power en-
gine and win be kept in operation night
and day.
The bedrock on Mississippi Bar is
about 80 feet below the surface, and
this will all be worked out Some
stratas are richer than others, but all
the gravel will. it is claimed, yield gold
in paying quantities.
The enterprise has been inaugurated
by w. P. Bonbright G. Co. of Colorado
Springs, Col, who are also interes ted
at Cripple Creek mines in that State.
They have plenty of capital behind
them. and have bonded about 100 acres
of bench land. or gravel deposits, along
the American River. which they pro-
pose to mine by this method.
The surface of this ground was
scratched over by placer miners in
early days. but they could not go to
any depth on account of the water that
flowed in upon them and which they
could not dispose of. With this dredger
however, 1t is very different While il
can obtain, from the ditch all the water
required for floating it and washing the
gravel, sipage water will be welcomed
as 1t will not only be no obstacle to
successful operation but a direct aid
thereto.
If this enterprise should prove the
success that is anticipated-and which
its promoters feel assured it will-they
Will build and operate other machines
on ground they have bonded along the
river.
The scene at the launching of the big
dredger yesterday was animated and
interesting. The visitors gathered on
the embankments surrounding the ex-
cavation and watched the mechanics
as they prepared for the release of the
big barge Miss Mabel Duden, teacher
of the Fair Oaks school, had been
chosen to do the christening act
When all was in readiness p. C. Cohn
of Folsom addressed the visitors
speaking of the Importance of the
undertaking and the benefits to flow
from it. Then Miss Duden stepped for
ward and breaking a bottle of wine
against the bow of the barge, said: Il
christen thee Mabel
The Folsom Band struck up a lively