Evening star. [volume] (Washington, D.C.) 1854-1972, 1855-04-23
+ EVENING STAR,
TIE ISLE RoYALs NINE, Sc.-IETEI
EsrIEG DISCOVERIES,

ter dated at Portage Lake, Lake Superior,
March Is. 1855:
The Isle Rcyale Mine having been
worked mere extensively than any other
in this district, short account of its
operations may not be uninteresting at
this time.
Work was commenced in May, 1852,
with small force, which did not exceed
on an average seventeen men the frs
year. During tie second year the num-
Der of men engaged was about fifty.
The labor, up to the close Of the second
year, was expended in opening the mine,
by shafts and drifts, and the usual sur
face Improvements OF buildings, clearing
lands, and constructing a road to the
lake-a distance of about mile.
Early last spring preparations were
begun for erecting stamp works, which
were so far completed as to commence
running with eight heads in November.
In December, the number of heads was
increased to sixteen, which is the number
at present in use.
The stamp building is a large and
commodiouS structure, 140 feet by GO,
with boiler and furnace room attached
The building is designed to accommodate
sixty four heads of stamps, ard most of
the machinery and fixtures for half that
number are now On the ground.
The product Of sixteen heads has been
equal 20 about ten tons Of No. l coppe,
per month, and as it is now ascertained
that the barrel work and masses will
amount to as much, if not more, the
whole product of the mine, working six
teen heads Of stamps, will be twenty
tons per month. The actual yield has
been, for the months of January and
February, Al tons 1864 pounds.
The ground opened at the Isle Royale,
and its position in the mine, March LIST,
is as follows: shafts sunk to the first
level, 70 feet; of these are extended TO
the second level, ard one to the third
The drifting on the first level is $50, AID
On the second 452 feet Reducing the
whole work to cubic fathoms, we have
the result stated below:
1856 feet shafting, equal to "a fa:homs
1902 drifting, I7l6
stcpipg 255 0 ::
Total AMT cf ground br1kea $3.50 d"
The actual product of the above ground
has been 126 tons 1,3l6 pounds rough
copper, Or 1861 pounds for every iathom
of ground broken. Reducing this to pur,
ingot copper, the amount at 70 per cen
will be SO tons 1921 pounds. or 277t
pounds for every fathom.
| believe these figures settle the ques-
ton in regard to the Isle Royale's max
ing a paying mine. As the stopin,
progresses the yield of copperper fathom
will be considerably increased, since, III
shafting and drifting, a large quantit,
of dead ground necessarily has to be
opened.
The operations for the month of Feb
ruary show very gratifying result
Amount CT copper prepared for market
81 tons 402 lbs. rough, or IA tons ,681
lbs. of ingot copper, which, at $3.50 per
ton, will bring $8, ,1G4 IS. The expenses
at the mine for thu same month were
50 7l5 II, leaving a balance in favor of
the company of S., ,449 63. The expenses
at the mine for the month of February
were unusually low, but allowing 50, 900
more for regular monthly expenses, and
it will give a sum sufficient to supply l6
heads of stamps, and keep the work eff
opening the mine in advance of the step
ing, and still aff,rd a net profit per
month Of $3,449 63. | have no doubi
this rate can be maintained.
There were shipped in the fall of 1853
frcm the Isle Royale Mine Is tons 1879
lbs; in the fall of 1854, 80 tons l,964
lbs, and by the 18th of May next, LOG
tons will be barreIed up ready for ship
ment.
The Minnesota Mine produced the first
year 6i tons of copper; the second 81,
and the third 103-making a difference
of only about toas for the same length
of time in favor of the Mlnnesota-one of
the richest copper mines in the world.
Some very respectable sized masses
have been taken from the Isle RoYale this
winter-two that will weigh 1000 lbs.
each and one over 5000.
The Isle Royale is now working at
very handsome profit, and l cannot see
any necessity or excuse for the expendi-
lures at the mine exceeding for single
month the amount ofcopper produced
The Portage Mine, which joins the Isle
Royale towards the lake, is opened near
ly to the same extent, but it has not any
stamp works in operation. They are,
however, now in course of construction,
and are designed to be completed early
in the coming season. The adit level in
tended for drainage is nearly through,
and the appearance of the mine is in all
respects highly encouraging. The ground
opened the past winter has been some of
the richest yet broken in the mine. The
character of the Portage, in respect to
richness and size of vein, is so similar to
the Isle Royale that it will be safe to as
sumo that, with l6 heads Of stamps, it
will yield an equal amount of copper, and
the difference probably will be that the
Portage will produce q greater amoun:
of stamp compared with barrel work.
The Portage possesses one OF two ad-
vantsges, in being nearer to the lake,