Western news and the Libby times. [volume] (Libby, Mont.) 1920-1933, 1932-03-03

Victor Miller of st. LOUIS.
gold commercially recoverable. The
necessity of minimum resistance to
transportation is due to the fact that
the water must be made to perform the
highest possible duty. A high resistance
to wear reduces the work of replacing
and maintaining the rifles and also
preserves their saving capacity
When he began experimenting to find
solution Of the above problem Bouery
had the choice of Is, Is, As and IS
pound rails. He discarded the 16 and Is
pound rails as too light; the SIS for
the reason that the web and flange
were too large in comparison with the
head. He adopted the As pound rail, but
later substituted 40 pounds for rea-
sons of economy
Setting of the Rifles
Two-by-six boards are cut into pieces
as long as the sluice is wide. These
are set on edge crossWays in the bot
tom Of the sluice at intervals OF two
inches or more and held apart by
wooden blocks On each of these pieces
a rail is set, also crossWise of the sluice,
making pocket nine inches deep. The
rails are locked together in various
ways. Bouery used cast iron Tugs. The
lug was shaped to fit between the bot
tom and top of the rail with bolts
holes being drilled in the neck Of the
rail for that purpose. The second rail
was slipped into place, engaging the
opposite side Of the lug. This rail in
turn was fitted with Tugs to hold the
next rail and so to the end Of the sluice.
When all the rails were in place they
were thus firmly locked together but
easily and quickly removed by start
| ing at the lowest rail.
In our operation we use wood in
stead Of cast iron Tugs as the sluice
comparatively narrow (three feet)
and the grade Of the boxes lower "a
inches to II foot box).
Bouery reports that he found but
little gold between the rails, the gold
having found its way to the space be-
tween the 2x6s On Libby creek we
use 25 and 30 pound steel with 2x6s
but we find large proportion OF the
gold between the rails-due no doubt
to the difference in gradient
Results OH Libby Creek
i The Nugget Placer on Libby creek
operated by the writer and his asso-
ciates, is an ancient stream channel
filed with gravel from Is to 80 feet
deep Present operations are on the
deepest part Of the channel. The first
or upper to feet IS a loose grave
; offering no difficulties either in exca-
waiting or recovery of values. The un-
deriving 27 to 20 feet however, ha.
its problems and these Of Difficult
nature. The deposit consists OF boul.
ders large and small, sand and flint
gravel all in matrix of stubborn
sticky clay. The values are embedded
of course, in this clay. In slulc
equipped with ordinary rifles the ella.
would be carried, undissolved, for
great distance In addition to the los
of gold in the undissolved clay, tn
operator would sustain loss by rea
son of the clay picking up and carry
ing off free gold lying on and betwee
the rifles.
All this loss, we find has bee
avoided by the use Of steel rails. tn
pounding action Of the water an
q boulders and other abrasive solids 0
i the sharp edges Of the hard steel GRO.
rifles dissolves the clay and release
: the values. The latter slide into I'll
pockets where they are safe from sue
\ vagrant chuncks Of clay as remain III
dissolved
Small Loss.
The major part Of Libby creek 60
q is fine; all of it is flat, tho not flax
The shape Of the coarse gold offers di
ficulties in recovery but we have foui
that with comparatively flat gra
and the use of steel rails the loss
negligible.
The writer would suggest to anyo
/ planning placer operation that he 0
! tain copy Of monograph writ
by Bouery and published in the Emf
neering and Mining Journal in its ISIS