The new North-west. [volume] (Deer Lodge, Mont.) 1869-1897, 1875-12-17
REDUCING ORES.
The MindelefsProcess Observation-Disclosures
estlng Experiments

From the San Francisco Chronicle, Nov. a5th.
Several gentlemen interested in the re-
dueing of metals from their ores, including
representatives from the press Of this city,
gathered at the corner of Main and Harri-
son yesterday to examine what is called the
sMindeleff process" The process has been
duly patented. It is remarkably simple
one, and if it will accomplish all it's inven-
tors claim for it, will come into general
use. 1t is based on the fact that hydrogen
unites powerfully with oxygen and sulphur
in statu nascente, and that gaseous carbon
possesses even greater power to eliminate
these and other impurities. The reducing
power of pure hydrogen has been long
known, and has in fact been variously en-
ployed in the laboratory, but this
GAS is PRACTICALLY USELESS
In the large way, on account of the great
cost of its production. Professor Mindeleff
seeks to substitute light carbureted hydro
gen, which may be chsaply prepared by the
dry distillation of wood or coal, for this ex-
pensive agent, and claims that the low per-
centages of carbon carried in his substitute
fulfill functions scarcely less valuable than
those to be expected from the vehicle, hy-
drogen itself. With these facts before him
Professor Mindeleff applies his discovery
in an apparatus consisting essentially Of
but two parts, viz : a retort kept at a red
heat for reducing the ore, and decompos-
ing chamber for converting coal gas into
light carbare ted hydrogen by depositing
the excess of carbon, which would other
wise coat the ore and interfere with its re-
duction.
ORDINARY ILLUMINATING GAS
Passes from the street mains and through
the decomposer to the mass Of heated ore
in the retort, while the various waste gases
such as sulphurous acid, ,sulphureted hydro
den, carbonic acid and water-vapor escape
through suitably arranged pipe, together
with the vapors of any metals or metalloids
which volatilize at or below the tempera
ture of the retort. The arsenic passes off
partly as vapor and partly as arseniureted
hydrogen, and the antimony distils off with
tolerable facility in the current of hydro
gen. All the other impurities are so reduced
in quality and modified that they can
readily be handled in the final processes of
smelling and refining. Messrs. Ruhm &
Lenhardt, metallurgists of this city, tested
the analysis, with the following result, a
description of the
INTERMEDIATE STAGES
OF the process being omitted. The ore was
tolerably firm carbonate when introduced
carrying abou SO per cent of copper. When
withdrawn the charge appeared as loosely
compacted Jumps of gangue, showing on the
surface and to the very heart of each threads
and globules of absolute metal, with parti-
cles SO finely divided as to constitute actual
copper sponge. Lumps of three and four
inches cube were thus reduced, and SO far
as the eye could Judge, not a particle of
copper had evaded the searching action of
the gas. Under the magnifyiDg glass, and in
strong sunlight, the clusters of metallic
fiber were in some instances really superb
in their brilliancy with the characteristic
i rcd Of copper.
THE EXPERIMENT
Was tried yesterday by placing about 300
pounds of carbonate of copper in a retort
and bringing it to red heat. The gas was
then admitted under pressure equal to
that afforded by a column of water four
inches high-the seal of the escape pipe be-
ing so set as to permit the slow effiux of the
waste gases. The ore was introduced cold,
and as it gradually approached the desired
heat, the flow Of steam and sulphurous acid
from the escape pipe was copious. At last
the steam ceased, showing that the ore
was sufficiently dried and after waiting
half hour to ensure the heating of the en-
tire mass of the charge, the flow OF gas
was turned on, the Cow of steam then recon-
menced with greater vigor than before, but
this time it had it's source in the chemical
union of the hydrogen of the gas with the
oxygen it was stripping from the ore. This
was
CONCLUSIVE EVIDENCE
That deoxidation was progressing. Stimuli
taneously with this surrender of oxygen,
sulphureted hydrogen and the vapor OF oi-
sulphide of carbon were given off in quan-
tity, the volume of the two latter foul gases
increased, and the carbonic oxide tame
added its weight to this evidence. AT the
end of about an hour the characteristic
yellow of the original coal gas began to
show at the test burner on the escape pipe,
and the completion of the treatment was
indicated at the end of two hours, by the
flame burning free, with the brilliant yell
low of the uncontaminated coal gas. The
ore was
a ToIERABLY FIRM CARBONATE
When introduced, carrying about thirty
two per cent of copper. When Withdrawn
the loose Jumps had the appearance des-
cribed in the test by Hahn & Luckhardt
The proc ess will undoubtedly be used for
the present i'm working copper ores, SO
abundant in our State, though it is claimed
thar it will work gold and silver ores with
equal facility. It is estimated that mine
able to furnish for reduction twenty tons
per day win pay clear profit Of $500, 600 a
year.
The REGULAR ARMY.-During the last
yea on two unusual care has been observed
in enlisting men for the regular army. Inc
moral character of applicants has been
subiect of close inquiry, and men of devel-
oped bad habits have been rejected. Io
this system Adjntant General Townsend
ascribes the great decrease OF deserters. In
1868, with an army Of $4,000, the deser-
tions reached 10000 a year. During this
wear. ending June 31st, the army being 25,-
.,,I,v o 05t s1asar.