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among the copper has amounted in one year to about $1,000.

of the pieces into which it was cut, but it is known to have exceeded 400 tons. Other masses have been taken out which presented a thickness of over five feet solid copper. The value of the silver picked out from earliest operations:

The reports of the company present the following statistics of the mine from its

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1859,

718

384,394

1,626

71

595,000 515,786

180,000

120,000

8 months to Sept. 1..... 1,431
Estimate, for the year.... 2,250

1860, In consequence of recent discoveries of masses of copper running into the sandstone off from the vein itself, the product of the year 1860 will considerably exceed that of any other year; the profits, however, are not proportionally large, owing to the low price of copper. To this the diminished prof its of 1858 and 1859 are partly to be attributed. The product for 1857, 1858, and 1859 was divided as follows:

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Besides the dividends named, the original stockholders have derived large profits from the sale of portions of the extensive territory, three miles square, which belonged to the company, and the organization upon these tracts of new companies.

Before the completion of the St. Mary's Canal, no exact records were preserved of the amount of copper sent from Lake Superior. But up to the close of navigation in 1854 it is supposed the total shipments from the commencement of mining in 1845 had been about 7642 tons of pure copper.

Since that time, the annual product of rough copper has been as follows:

Years.

lbs.

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2,200

2,125 1,910.3

1,910.8

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Total..... The condition of the Lake Superior mines at the close of the year 1860 is well presented in the business circular of Messrs. Dupee, Beck, & Sayles, of Boston, received since the preceding pages passed through the hands of the printer and stereotyper. From this we introduce the following additional matter. The depreciation in the price of copper from a maximum of 29 cents a pound of the few preceding years to a maximum of 24 cents and a minimum of 19 cents, had induced increased economy and care in the administration of the mines, the good effects of which were already beginning to be experienced :

"Freights to and from the mines from May to September were 25 per cent. less than in 1859. The transportation of a ton of copper from the lake shore to Boston, cost, after the opening of St. Mary's Canal, 1855, $20; in 1860, to Boston, $11, and to New York, $9. The substitution of bituminous coal for wood, which has been delivered during the past summer at the wharves of Portage Lake for $3.25 per ton, will save much money and leave the forests of the country for building materials and for timbering of the mines. With the wants of a rapidly increasing population, new and cheaper sources of supply are constantly

amount brought down to Marquette, the port of shipment, in 1860, was: of iron ore from the Jackson Company, 62,980 tons; Cleveland Company, 47,889; Lake Superior Company, 39,394; total, 150,263. Of pig iron, Pioneer Company, 3050 tons; S. R. Gay, 1800; Northern Company, 650; total, 6500. Ore valued at $3; pig at $25; aggregate value, $588,289.

The following statistics are presented of the principal mines:—

COMPARATIVE TABLE OF SHIPMENTS OF ROUGH COPPER
FROM LAKE SUPERIOR DURING THE SEASONS OF 1859
AND 1860.

The weights of the barrels have been deducted, and the
results are given in tons (2000 lbs.) and tenths.

Central...
Clark..

KEWEENAW DISTRICT.

Copper Falls..
Eagle River.
North American.

Northwest..
Phoenix.

Pittsburg and Boston..
Summit.

opening in the region itself. Many agricul-
tural products, hitherto sent up at great cost
from Lower Michigan, are now raised in the
neighborhood of the mines, and at the new
settlements on the south-western shores of
the lake, cheaply and abundantly. At
Portage Lake, a machine shop, an iron
foundry, and a manufactory of doors, sash-
es, blinds, etc., have been put in operation
during 1860. The smelting works of the
Portage Lake Company are now success-
fully refining the products of that district.
These works consist of four reverberatory and
two cupola furnaces, capable of refining 6000
tons per annum. The buildings are of the
most thorough and substantial character,
and the location of the works accessible, at
a very small cost of transportation, to all the
mines now wrought, or likely to be wrought Connecticut.
for many years hence, in that neighbor-
hood. Hitherto, to save cost of transporta-
tion to the smelting companies in other
states, it has been necessary to dress the
rough copper to an average probably of 70
per cent. Now, by the proximity of the
furnaces to the mines, a dressing of 50 per
cent. will answer the same purpose, while
the refined copper, hitherto rarely ready for C. C. Douglass.
the market before the 1st to 15th July, will Isle Royale.
be sent directly from the lake to New Franklin.
York or Boston, arriving there in ordinary Hancock.
seasons by the 1st of June. Further, there
will be added the new facility of obtaining Pewabic...
cash advances through the winter on the Portage.
warehouse receipts of the smelting company.
"The opening of the entry into Portage
Lake during the past season has been one of
the greatest improvements in the navigation
of the Lake Superior region since the com-
pletion of the ship canal around the falls of
St. Mary's river. At the comparatively
small cost of $50,000, steamers of the larg-
est class able to pass through the St. Mary's
Canal
may now enter Portage Lake, and dis-
charge their cargoes at the docks of the sever-
al companies located on its shores. Besides
avoiding the loss of time and expense of tran-
shipment hitherto necessary, the opening of
Portage Lake has provided one of the most
capacious and safest harbors in the world.
"In the Ontonagon district, a plank road
has been completed recently, facilitating to
a very great extent the transportation to
and from the Minesota, National, Rock-
land, and Superior mines.

"The iron interests of Lake Superior are rapidly attaining great importance. The

Huron.
Mesnard.

Quincy..

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ONTONAGON DISTRICT.

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Keweenaw District.
Portage.
Ontonagon.
Porcupine Mountain.
Sundry mines..

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Adventure.
Aztec.

Bohemian.
Evergreen Bluff.
Hamilton.
Mass...
Minesota.
National.

Nebraska.
Norwich.
Ogima.
Ridge.
Rockland.
Superior.

Toltec.

2,183.4 727.8

26.4

COPPER SMELTING

Franklin: the product for the year end- got copper. The receipts, including $2,ing November 30 has been 112 masses, 405 17 from sales of silver, were $292,weighing 72,166 lbs.; 721 barrels of barrel | 503 14. The expenditures were $272,work, 469,116 lbs.; and 67 barrels stamp 175 75, leaving net profit, $20,327 39. work, 63,816 lbs. Total, 605,098 lbs., equal to 180 tons refined copper. The actual shipments were about 267 tons rough, or 158 tons ingot copper. The stamps are Ball's, consisting of two pairs of two heads each. They did not commence work till November 19.

Huron: total shipments this year, 65 tons of 641 per cent. barrel work, and 12,311 lbs. of refined copper, smelted at the Portage Lake works. There is ready for the stamps an amount equivalent, at a fair estimate, to the quantity shipped this sea

son.

Isle Royale: total shipments this season 458 tons, averaging over 70 per cent. Preparations have been made for opening a large amount of ground during the winter, with a view to large shipments at the opening of navigation.

Minesota: November returns, 150 tons. The total shipments in 1860 were 1992 masses, and 2127 barrels of barrel and stamp work. Net weight, 4,366,718 lbs. This is the largest shipment made in one year by any mine at the lake. The promise for future production is as great, at least, as the result for this year.

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Pewabic: November product, 304 tons. The actual shipments for the season have been 2,727,032 lbs. The product for one year to November 30 was as follows: 467 masses, weighing 348,658 lbs.; 2294 barrels kiln or barrel work, weighing net, 1,450,778 lbs.; 342 barrels No. 1, stamp, 379,718 lbs.; 399 barrels No. 2, stamp, 889,973 lbs.; 401 barrels No. 3, stamp, 346,912 lbs.; add on tributers' account, 27,428. Total, 2,943,467 lbs.

The ores of copper, unlike those of most of the other metals, are not in general reduced at the mines; but after being concentrated by mechanical processes called dressing-which consist in assorting the piles according to their qualities, and crushing, jigging, and otherwise washing the poorer sorts

they are sold to the smelters, whose establishments may be at great distances off, even on the other side of the globe. The richer ores, worth per ton three or four times as many dollars as the figures that represent their percentage of metal, well repay the cost of transportation, and are conveniently reduced at smelting works situated on the coast near the markets for copper, and where the fuel required for their reduction is cheap. At Swansea, in South Wales, there are eight great smelting establishments, to which all the ores from Cornwall and Devon are carried, and which receive other ores from almost all parts of the world. It is stated that in this district there are nearly 600 furnaces employed, which consume about 500,000 tons of coal per annum, and give employment to about 4,000 persons besides colliers. The amount of copper they supply is more than half of that consumed by all nations. The total product of fine copper produced by all the smelting establishments of Great Britain for 1857 is stated to be 18,238 tons, worth £2,079,323.

The copper smelting works of the United States are those upon the coast, depending chiefly upon foreign supplies of ores, and those of the interior for melting and refining the Lake Superior copper. There are also the furnaces at the Tennessee mines, which have been already noticed. The former are situated at the following localities: At

The smelting returns are not yet all made, but on an estimate based on past experience, the result will not vary much from 2,030,992 lbs., or about 1000 tons of ingot cop-Point Shirley, in Boston harbor, are the per.

During the year there have been shipped 1533 ounces of silver.

Pittsburg and Boston: November product, 114 tons. Total shipments, 1357 tons. Total product for the year, 1402 tons. The annual report recently published gives the result of the year ending December 1, 1859. The product for that year was 1,099 tons, yielding 64 per cent., or 707 tons in

furnaces of the Revere Copper Company, which also has rolling mills and other works connected with the manufacture of copper at Canton, on the Boston and Providence railroad. At Taunton, Mass., a similar establishment to that at Canton is owned by the Messrs. Crocker, of that town. There are smelting furnaces at New Haven, Conn.; at Bergen Point, in New York harbor; and at Baltimore, on a point in the outer harbor.

The furnaces established for working the Lake Superior copper are at Detroit, Cleveland, and Pittsburg. At the last named are two separate establishments, with each of which is connected a rolling mill, at which the ingot copper is converted into sheets for home consumption and the eastern market. A furnace was also built at Portage lake, Lake Superior, in 1860, of capacity equal to melting 6000 tons of copper annually. The details and extent of the operations carried on by the smelting works appear to have been carefully kept from publication. In a work on "Copper and Copper Smelting," by A. Snowdon Piggott, M. D., who had charge of the chemical assays, etc., for the Baltimore Company, published in 1858, while the English processes are fully described, no information is given as to the methods adopted at the American works; and of their production all the information is contained in the two closing sentences of the appendix, as follows: "Of the coppersmelting establishments of the United States I have no statistics. Baltimore turns out about 8,000,000 pounds of refined copper annually." Applications which have been made by the writer to the proprietors of several of the establishments for information as to the business, have been entirely unsuccessful. The total production of copper in 1858 was supposed to be about 13,000 tons per annum; and of this about 7000 tons were required by the rolling mills for making sheet copper, sheet brass, and yellow

metal.

The French treatise on Metallurgy by Professor Rivot contains the only published description of the American method of smelting copper. By the English process, the separation of the metal from its ores is a long and tedious series of alternate roastings or calcinations, and fusions in reverberatory furnaces. The system is particularly applicable to the treatment of poor, sulphurous ores contaminated with other metals, as iron, arsenic, etc., and can only be conducted to advantage where fuel is very cheap, the consumption of this being at the rate of about 20 tons to the ton of copper obtained. The process employed in Germany is much more simple, and the methods in use at the American smelting works are more upon the plan of these. Blast or cupola furnaces supply at some of them the place of reverberatories, and the separation of the metal is completed in great part by

one or two smeltings. The treatment of the Lake Superior copper is comparatively an easy operation. For this large reverberatory furnaces are employed, through the roof of which is an opening large enough to admit masses of 3 to 3 tons weight, which are raised by cranes and lowered into the furnace. The barrels of barrel work are introduced in the same way, and left in the furnace without unpacking. When the furnace is charged, the opening in the top is securely closed by fire-proof masonry, and the fire of bituminous coal is started, the flame from which plays over the bridge, and, reflected from the roof, strikes upon the copper, causing it gradually to sink down and at last flow in a liquid mass. A small portion of the copper by the oxidizing action of the heated gases is converted into a suboxide, which is partially reduced again, and in part goes into the slags in the condition of a silicate of copper, the metal of which is not entirely recovered. The mixture of quartz, calcareous spar, and epidote accompanying the copper, is sometimes such as to melt and form a good cinder without addition of any other substance, but usually some limestone or other suitable material is added as a flux. Complete fusion is effected in 12 to 15 hours according to the size of the masses, and this is kept up for about an hour in order that the fine particles of copper may find their way through the fluid slag, which floats upon the metal. Working tools called rabbles are then introduced through the side-doors of the furnace, and the charge is stirred up and the slag is drawn out through the door. It falls upon the ground, and is taken when sufficiently cool to the cupola or slag furnaces where it is chilled with water to render it easy to break up. Those portions which contain as much as one fourth per cent. of copper are reserved to be passed through the slag furnace. The total amount of slag is usually less than 20 per cent. of the whole charge. In the melting the copper absorbs carbon, which if allow ed to remain would render it brittle and unfit for use. To remove it the fire is so arranged that the gases pass through with much unconsumed air; this playing on the surface of the copper produces a suboxide of the metal, which in the course of half an hour is quite taken up by the copper, and coming in contact with the particles of carbon the oxygen combines with this, and removes it in the form of carbonic acid gas.

Labor, 15 hands, at $1.50..
Bituminous coal, 5 tons, at $5
Wood and charcoal..

Repairs to furnace, average for the season..

$22.50 25.00 1.25

2.00 $50.75

To this should be added, for superintendence, office, and general expenses, perhaps ten dollars more, which would make the cost for six or seven tons of ingot copper, $60.75, or $9 to $10 per ton. At Pittsburg the rate charged has been $11 per ton; and fuel is there afforded at about one third the amount allowed in the above estimate.

It now remains to remove the excess of oxygen introduced, which is effected by the ordinary method of refining. A large proportion of fuel is employed on the grate for the amount of air admitted through it, so that the flames as they pass over the bridge convey little free oxygen, and the surface of the metal is covered with fine charcoal. After a little time a pole of green wood is thrust into the melted copper and stirred about so long as gases escape from the surface. It is then taken out, and if on testing the copper some suboxide still remains, the refining is cautiously continued with char- The cupola furnaces for treating the slags coal, and just when, as appears by the tests, are of very simple plan and construction. all the oxide is reduced, the work of dipping They are of cylindrical form, about ten feet out the metal is commenced. This is done high, and three feet diameter inside. Their by large iron ladles, the whole set of men walls, the thickness of a single length of employed at two furnaces, to the number fire brick, are incased in boiler-plate iron, of about 12, coming to this work and taking turns in the severe task. They protect themselves from the intense heat by wet cloths about their arms, and as quickly as possible bale out a ladle full of copper and empty it into one or more of the ingot moulds, of which 36 are arranged in front of the furnace-door upon three parallel bars over a trough of water. As the metal becomes solid in each mould, this is upset, letting the ingot fall into the water. The weight of the ingot being 20 pounds, the filling of them all removes 720 pounds of copper from the furnace. The metal that remains is then tested, and according to its condition the discharging may be continued or it may be necessary to oxidize the copper again and repeat the refining, or merely to throw more charcoal upon the surface and increase the heat. The time required to ladle out the whole charge is from four to six hours. When this is completed the sole of the furnace is repaired, by stopping the cracks with sand and smoothing the surface to get all ready for the next charge; and at the same time the second furnace has reached the refining stage of the process. One charge to a furnace is made every evening, and as in the night it is necessary only to keep up the fires, the great labor of the process comes wholly in the day time.

The following is the estimated cost at Detroit of the smelting, on a basis of two furnaces, each of which is charged with four and a half to five tons of mass copper, consuming two and a half tons of coal, and producing from three to three and a half tons of ingots:

and stand upon a cast-iron ring, which is itself supported upon four cast-iron columns about three feet above the ground. Transverse iron bars support a circular plate, and upon this the refractory sand for the sole of the furnace is placed, and well beaten down to the thickness of a foot, with a sharp slope toward the tapping hole. A low chimney conveys away the gaseous products of combustion, and through the base of it the workmen introduce the charges. The blast is introduced by three tuyeres a foot above the sole; but before it enters the furnace it is heated by passing through a channel around the furnace. A steady current is obtained by the use of three double acting blowing cylinders, which give a pressure equal to about three and a half inches of mercury.

The hands employed at the Detroit establishment, besides the superintendent and head smelter, are eighteen furnace men and from five to ten workmen, according to the arrivals of copper during the season of navigation. After the stock thus received is worked up, the furnaces remain idle during the remainder of the winter.

USEFUL APPLICATIONS OF COPPER.

The uses of copper are so numerous and important that the metal must rank next in value to iron. In ancient times, indeed, it was the more useful metal of the two, being abundant among many nations to whom iron was not known. In the ancient Scandinavian tumuli recently opened in Denmark, among the various implements of stone were found swords, daggers, and knives, the blades of which were, in some instances, of copper,

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