Imágenes de páginas
PDF
EPUB
[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][ocr errors][merged small][ocr errors][merged small][ocr errors][merged small][ocr errors][ocr errors][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][ocr errors][ocr errors][ocr errors][ocr errors][merged small][ocr errors][merged small][ocr errors][merged small][ocr errors][ocr errors][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][ocr errors][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]
[merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][ocr errors][ocr errors][merged small][merged small][ocr errors][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small]

Grand total production of iron from

In addition to this amount, the importations for the year 1856 of iron designed for manufacture are estimated at 363,998 tons, consisting of Scotch pig, 55,403 tons; rolled and hammered iron, 298,275 tons; and scraps, 10,320 tons; and if to this be added for old rails reworked, 100,000 tons, and for scrap, 25,000 tons, the total amount of iron entering into domestic consumption was 1,330,548 tons. The importation of railroad iron not included in the above was 167,400 tons. The proportion of foreign iron introduced into the general consumption, not including rails, was about 30 per cent.

The value of the immediate products of the manufacture of domestic iron is thus given at the prices current in 1856:

Product.

Tons.

1,650

18,710

4,487

1,182

640

40

252

1,222

450

28,633

812,917

841,550

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][ocr errors][merged small][merged small][merged small][merged small]

band....

Hammered iron....

235,425
21,000

a 65, 15,302,625

Total.

The opening of the war, in 1861, gave an a 125, 2,625,000 extraordinary impetus to iron production $47,771,236 and manufacture. The tariff and other causes reduced the importation to a mini

Mr. Smith presents the following conclu- mum, while the demand for iron for the sion to the "Statistical Report of the Iron fabrication of small arms and cannon; for Manufacture:' "The great facts demon- the construction of the large fleet of ironstrated are, that we have nearly 1,200 effi- clads, and for the other war vessels; for the cient works in the Union; that these pro- building of locomotives, the casting of car duce annually about 850,000 tons of iron, wheels and furnishing the vast quantity of the value of which in an ordinary year is railroad iron needed to repair the old tracks $50,000,000; of this amount the portion destroyed by the contending armies, and to expended for labor alone is about $35,000,000."

The following table gives the different kinds of pig metal and the total amount produced in each year since 1856:

Tons
Anthracite

Tons raw
Bituminous

YEAR.

Pig Iron.

Coal and Coke

Tons
Charcoal
Pig Iron.

Pig Iron.

1857,

390,385

77.451

1858,

361.430

58,351

[blocks in formation]

84,841

[blocks in formation]

122,228

830,321 285,313 284,041 278,331

[blocks in formation]
[blocks in formation]
[blocks in formation]
[blocks in formation]
[blocks in formation]
[blocks in formation]

1564,

684,018

[blocks in formation]
[blocks in formation]

262,342

[blocks in formation]

286,996

332,280

[blocks in formation]

318,647

344,341

[blocks in formation]
[blocks in formation]
[blocks in formation]

392,150

1-70, 1871,

940,500

550,000

[blocks in formation]

360,000
875,000

Total. 798,157

840,627

731,544

947,604

831,282

1,461,626

lay the tracks of new roads, extended the business vastly beyond all former precedent; and the requirement that the Pacific railroad and its branches shall be constructed solely of American iron, as well as the increase in its use for buildings, and for shipping, have maintained it in a prosperous condition. The manufacture of steel and the other 705,095 manufactures of iron, aside from those al919.770 ready enumerated, brought the aggregate 787,662 production and manufacture of iron and 1,135,497 steel, in 1860, up to $285,879,510. The 1,350,943 revenue tax paid on iron and steel manufac1,603,000 tures in 1864 indicates that the product of 1,850,000 the branches taxed amounted to about 1,900,000 $123,000,000. This estimate was far below The manufacture of iron rails has existed the production, as many branches were not for nearly twenty-five years in the United taxed, and the returns of that year were imStates, but has only assumed any great mag-perfect. The production and manufacture of nitude since 1854. The annual production 1865 were not less than 400 millions of dollars. of American rails since 1861 has been: 1861, There is every reason to expect that the de189,818 tons; 1862, 213,912; 1863, 275,-velopment of the iron mines will be pushed 768; 1864, 335,369; 1865, 356,292; 1866, 430,778; 1867, 462,108; 1868, 506,714; 1×69. 593,586; 1870, 620,000; 1871, 722,000 tons. In the last named year, 572,386 tons were imported from Great Britain.

1,916,641

The census of 1860 gives the following statistics of the iron production and manufacture of that year. There had been very little progress in the production of iron in the country for several years previous, in consequence of the very low rate of duty at which foreign railroad and other iron was admitted.

Iron blooms, valued at..... $2,623,178
Pig iron....
20,870,120
Bar, sheet and railroad iron.. 31,888,705

forward with constantly increasing energy, and that the time is not far distant when many of the great repositories of ores we have described-now almost untouchedwill be the seats of an active industry and centres of a thriving population, supported by the home markets they will create. The great valley of the west, when filled with the population it is capable of supporting, and intersected in every direction with the vast system of railroads, of which the present lines form but the mere outlines, will itself require more iron than the world now produces, and the transportation of large portions of this from the great iron regions of northern Michigan and Wisconsin, and of

coal back to the mines, will sustain larger lines of transportation than have ever yet been employed in conveying to their markets the most important products of the country. The importation of foreign iron-already falling off in proportion to the increased consumption-must, before many years, cease, and be succeeded by exports for the supplies of other nations less bountifully provided for in this respect than the United States and Great Britain.

CHAPTER II.
COPPER.

substances by the mechanical processes of
assorting, crushing, washing, jigging, etc.,
and brought up to a percentage of 6 or 7 of
copper, it is in Cornwall a merchantable ore,
and the mine producing in large quantity the
poor material from which it is obtained may
be a profitable one. Vitreous copper, known
also as copper glance, and sulphuret of cop-
per, is a lead gray ore, very soft, and con-
tains 79.8 per cent. of copper, united with
20.2 per cent. of sulphur. It is not often
found in large quantity. Variegated or pur-
ple copper is distinguished by its various
shades of color and brittle texture. It yields,
when pure, from 56 to 63 per cent. of copper,
21 to 28 of sulphur, and 7 to 14 of iron.
The red oxide is a beautiful ore of ruby red
color, and consists of 88.8 per cent. of
cent. of cop-
per and 11.2 per cent. of oxygen. It is
rarely found in sufficient quantity to add
much to the products of the mines. Green
malachite is a highly ornamental stone, of
richly variegated shades of green, famous as
the material of costly vases, tables, etc., man-
ufactured in Siberia for the Russian govern-
ment. It is always met with in copper
mines, especially near the surface, but rarely
in large or handsome masses. It consists
of copper 57.5, oxygen 14.4, carbonic acid
19.9, and water 8.2 per cent. Chrysocolla
is a combination of oxide of copper and
silica, of greenish shades, and is met with as
an incrustation upon other copper ores.
often closely resembles the malachite in ap-
pearance. It contains about 36 per cent. of
copper.

It

THE early attempts to work copper mines in the United States have already been alluded to in the introductory remarks to the department of this work relating to mining industry. The ores of this metal are widely distributed throughout the country, and in almost every one of the states have been found in quantities that encouraged their exploration in the great majority of cases to the loss of those interested. The metal is met with in all the New England states, but only those localities need be named which have at times been looked upon as important. Copper occurs in a native or metallic state, and also in a variety of ores, or combinations of the metal with other substances. In these forms the metallic appearance is lost, and the metal is obtained by different metallurgical operations, an account of some of which will be presented in the course of this chapter. Until the discovery of the The first mines worked in the United Lake Superior mines, native copper, from its States were peculiar for the rich character scarcity, was regarded rather as a curiosity of their ores. These were, in great part, than as an important source of supply. The vitreous and variegated copper, with some workable ores were chiefly pyritous copper, malachite, and were found in beds, strings, vitreous copper, variegated copper, the red and bunches in the red sandstone formation, öxide, the green carbonate or malachite, and especially along its line of contact with the chrysocolla. The first named, though con- gneiss and granitic rocks in Connecticut, and taining the least proportion of copper, has with the trap rocks in New Jersey. The furnished more of the metal than all the mine at Simsbury, in Connecticut, furnished other ores together, and is the chief depen- a considerable amount of such ores from the dence of most of the mines. It is a double year 1709 till it was purchased, about the sulphuret of copper and iron, of bright yel- middle of the last century, by the state, low color, and consists, when pure, of about from which time it was occupied for sixty 34 per cent. of copper, 35 of sulphur, and years as a prison, and worked by the con30 of iron. But the ore is always inter- victs; not, however, to much profit. In mixed with quartz or other earthy minerals, 1830 it came into possession of a company, by which its richness is greatly reduced. As but was only worked for a short time afterbrought out from the mine it may not con- ward. may not con- ward. On the same geological range, but tain more than 1 per cent. of copper, and lying chiefly in the gneiss rocks, the most when freed as far as practicable from foreign productive of these mines was opened in

reached in 1853 the depth of 396 feet. The sales of copper ores during the three years the mines were actively worked amounted to over $40,500; but the product was not sufficient to meet the expenditures.

1836, in Bristol, Conn. It was vigorously-extensive mining operations have been worked from 1847 to 1857, and produced carried on; a shaft upon the latter having larger amounts of rich vitreous and pyritous ores than have been obtained from any other mine in the United States. No expense was spared in prosecuting the mining, and in furnishing efficient machinery for dressing the ores. Although 1800 tons of ore, producing over $200,000, were sent to market, the ore yielding from 18 to 50 per cent. of copper, the mine proved a losing affair, and was finally abandoned in 1857.

The mines in Frederick county, Maryland, in the neighborhood of Liberty, were near the red sandstone formation, though included in argillaceous and talcose slates. A number of them have been worked at different times up to the year 1853, when they were finally given up as unprofitable.

A more newly discovered and richer copper district in Maryland is near Sykesville, on the Baltimore and Ohio railroad, 32 miles from Baltimore, in a region of micaceous, talcose, and chloritic slates. A large bed of specular iron ore lying between the slates was found to contain, at some depth below the surface, carbonates and silicates of copper, and still further down copper pyrites. In the twelve months preceding April 1, 1857, 300 tons had been mined and sent to

and the mine was reported as improving. The ore sent to the smelting works at Baltimore, in December of that year, yielded 16.03 per cent. of copper. Within seven miles of Baltimore the Bare Hill mine has produced considerable copper, associated with the chromic iron of that region.

The New Jersey mines have all failed. from insufficient supply of the ores. The Schuyler mine, at Belleville, produced rich vitreous copper and chrysocolla, disseminated through a stratum of light brown sandstone, of 20 to 30 feet in thickness, and dipping at an angle of 12°. During the periods of its being worked in the last century, the excavations reached the depth of 200 feet, and were carried to great distances on the course of the metalliferous stratum. The mine was then so highly valued that an offer of £500,000, made for it by an English company, was refused by the proprietor, Mr. Schuyler. In market, the value of which was $17,896.92, 1857-58 attempts were made by a New York company to work the mine again, but the enterprise soon failed. Among the other mines which have been worked to considerable extent in New Jersey are the Flemington mine, which resembled in the character of its ore the Schuyler mine, and the Bridgewater mine, near Somerville, at which Like the last two named, all the other lonative copper in some quantity was found in calities of copper ores of any importance the last century; two pieces met with in 1754 along the Appalachian chain and east of it weighing together, it was reported, 1,900 lbs. are remote from the range of the red sandA mine near New Brunswick also furnished stone, and belong to older rock formations. many lumps of native copper, and thin sheets In the granites of New Hampshire, pyritous of the metal were found included in the sand- copper has been found in many places, but has stone. At different times this mine has been nowhere been mined to any extent. In Verthoroughly explored, to the loss of those en-mont, mining operations were carried on for gaged in the enterprise. In Somerset county, several years upon a large lode of pyritous the Franklin mine, near Griggstown, has been copper, which was traced several miles worked to the depth of 100 feet. Carbonate through Vershire and Corinth. At Strafand red oxide of copper were found in the ford, pyritous ores were worked in 1829 and shales near the trap, but not in quantity suf- afterward, both for copperas and copper. In ficient to pay expenses. In Pennsylvania, New York, excellent pyritous ores were pronear the Schuylkill river, in Montgomery and duced at the Ulster lead mine in 1853. Chester counties, many mines have been Among other sales of similar qualities of ore, worked for copper and lead at the junction one lot of 50 tons produced 24.3 per cent. of of the red sandstone and gneiss. Those copper. veins included wholly in the shales of the In Virginia, rich ores of red oxide of copred sandstone group were found to produce per, associated with native copper and pyricopper chiefly, while those in the gneiss were tous copper, are found in the metamorphic productive in lead ores. At the Perkiomen slates at Manasses Gap, and also in many and Ecton mines-both upon the same lode other places further south along the Blue

Ridge. The very promising appearance of the ores, and their numerous localities, would encourage one to believe that this will prove to be a copper region, were it not that, when explored, the ores do not seem to lie in any regular form of vein. In the southern part of the state, in Carroll, Floyd, and Grayson counties, copper was discovered in 1852, and mines were soon after opened in a district of metamorphic slates, near their junction with the lower silurian limestones. The copper was met with in the form of pyritous ore, red oxide, and black copper, beneath large outcropping masses of hematite iron ore, or gossan. Some of the shipments are said to have yielded over 20 per cent. of copper. The amount of ores sent east, over the Virginia and Tennessee railroad, in 1855, was 1,931,403 lbs.; in 1856, 1,972,834 lbs.; and in the nine months ending June 30, 1857, 1,085,997 lbs.; 1858, 688,418 lbs.; 1859, 1,151,132 lbs.; and 1860, 2,679,673 lbs. Copper ores are very generally met with in the gold mines of this state, and further south, but the only one of them that has been worked expressly for copper is that of the North Carolina Copper Company, in Guilford county. From this a considerable amount of pyritous copper ores were sent to the north in 1852 and 1853.

In Tennessee, an important copper region lies along the southern line of Polk county, and extends into Gilmer county, Georgia. The ore was first found in 1847, associated with masses of hematite iron ores, which formed great outcropping ledges, traceable for miles from south-west to north-east along the range of the micaceous and talcose slates. An examination of the ores, made to ascertain the cause of their working badly in the furnace, was the means of corroborating or giving importance to the discovery of the copper. In 1851 copper mining was commenced, and afterward prosecuted with great activity by a number of companies. The ore was found in seven or eight parallel lodes of the ferruginous matters, all within a belt of a mile in width. At the surface there was no appearance of it, but as the explorations reached the depth of seventy-five or one hundred feet below the surface of the hills, it was met with in various forms, resulting from the decomposition of pyritous copper, and much mixed with the ochreous matters derived from a similar source. In a soft black mass, easily worked by the pick, and of extraordinary dimensions, were found

intermixed different oxides and other ores of copper, yielding various proportions of metal, and much of it producing 20 per cent. and more, fit to be barrelled up at once for transportation. This ore spread out in a sheet, varying in width at the different mines; at the Eureka mine it was 50 feet wide, and at the Hiwassee 45 feet, while at the Isabella mine the excavations have been extended between two walls 250 feet apart. In depth this ore is limited to a few feet only, except as it forms bunches running up into the gossan or ochreous ores. Below the black ore is the undecomposed lode, consisting of quartz, more or less charged with pyritous copper, red oxide, green carbonate, and gray sulphuret of copper; and it is upon these the permanent success of the mines must depend. About 14 mining companies have been engaged in this district, and the production of the most successful of them was as follows, up to the year 1858: Isabella, 2,500 tons; Calloway, 200; Mary's, 1,500; Polk county, 2,100; Tennessee, 2,200; Hiwassee, 2,500; Hancock, 2,000— making a total of 13,000 tons, yielding from 15 to 40 per cent. of copper, and worth $100 per ton, or $1,300,000. In addition to this, the products of the London mine, yielding an average of 45 per cent. of copper, amounted to over $200,000 in value; and the products of the Eureka mine were rated for 1855 at $86,000; for 1856 at $123,000; and for 1857 at $136,000. The value of the ores remaining at the mines too poor to transport, but valuable to smelt in furnaces on the spot, was estimated at $200,000 more. Furnaces for smelting, on the German plan, were in operation in 1857, and produced the next year 850 tons of matt, or regulus. At the Eureka mine, in 1858, there were 4 reverberatory furnaces, 2 blast, and 2 calcining furnaces. The fuel employed is wood and charcoal. By the introduction of smelting operations, ores of 5 to 6 per cent. are now advantageously reduced.

In 1857 the mines of a large portion of this district were incorporated into the socalled Union Consolidated Mining Company, and most of the other mines were taken up by the Burra Burra Company and the Polk County Company. The principal interests in the last two are held in New Orleans. The first named own 11 mines, of which they are working three only, with a monthly production of 750 to 800 tons of 12 per cent. copper, besides 5 or 6 tons of precipitate

« AnteriorContinuar »