2. Copper deposits of the Mississippi valley, yielding ores, chiefly pyritous, in the lower silurian rocks. These are not now worked to any extent.

3. Cupriferous deposits of the Atlantic States, embracing copper-bearing veins of the metamorphic paleozoic age in the Appalachian chain; deposits in the new red sandstone, occurring in Connecticut and New Jersey, and now abandoned; and veins traversing the new red sandstone and the older metamorphic r cks in Chester and Montgomery counties, Pennsylvania, and extensively worked. Of these the Lake Superior mines are immeasurably the richest. Previous to the opening of Saint Mary's canal, no exact records were kept of the copper shipped from this region. Up to the close of 1854, the aggregate production is estimated at 7,642 tons of pure copper. The subsequent annual shipments, up to 1860, are as follows:

The substitution of bituminous coal for wood has greatly cheapened the process of smelting, while freights have declined at least twenty-five per cent., thus materially lessening the cost of bringing the metal into market.

Copper mining is prosecuted in different localities represented under the third head of Whitney's classification as above. From Virginia the copper ores sent eastward over the Virginia and Tennessee railroad increased from 1,931,403 pounds in 1855 to 3,679,673 pounds in 1860. Considerable quantities are also produced in New Hampshire, Vermont, New York, and Tennessee.

Copper manufactures, in 1860, were represented by 90 establishments, in all branches above the extraction of ore from the mine, employing a capital of $4,752,550. The cost of the raw material used was $7,631,598, and the cost of labor, paid to 1,639 hands, was $655,256. The profit was $1,245,536, or 27 per cent. on the capital.

Lead.-Mr. Whitney arranges our lead-bearing veins and deposits into two grand divisions: 1. Those of the Atlantic States; and 2. Those of the Mississippi valley.

In the first grand division the mines lowest in the geologic series are found in the azoic formation in St. Lawrence county, New York, in the vicinity of Rossie. The veins are transverse, cutting the gneiss rock in nearly vertical lines. The ore is galena, generally free from zinc and iron, but intercalated with calcareous spar. In the belt of metamorphic palæozoic rocks flanking the Appalachian chain on the east and cropping out in numerous localities, especially in New England, are considerable deposits of galena more or less argentiferous and always associated with blende, copper and iron pyrites. The veins are usually parallel to the dip of formations and of the segregated class, though often of large development, forming powerful and well-marked lodes. They have failed to be profitable on account of being mixed with too great a proportion of other substances, the manipulation of which requires greater expenditure of capital and skill than has yet been secured. In the unaltered lower silurian rocks of New York are some apparently irregular deposits not very extensive, recently worked to a limited degree.

The lead regions of the Mississippi valley are divided into two districts: 1. Upper Mississippi; 2. Missouri.

In the former the deposits consist of non-argentiferous galena, in irregular and gash veins, in the lower silurian limestone. These are found principally in

Wisconsin, yet extending into Illinois and Iowa, including an area of 2,880 square miles. The galena is remarkably pure, with a rare occurrence of carbonates, phosphates, or other oxidized combinations. It is found in masses commonly called "gravel mineral" or "float mineral" in the latest alluvial strata, or deposited in vertical rock fissures or in horizontal flat sheets. These deposits are not sufficient to warrant very extensive machinery or great outlay of capital. Their superficial location, however, does not demand any such elaborate working. The lead production of this region has probably reached its maximum.

The lead mines of Missouri being in nearly the same geological position as those of the upper Mississippi are mostly of a similar character. As late as 1848 our exports of lead exceeded our imports. Since that time the tide has turned, the imports exceeding the exports $1,102,825 in 1852, and $2,613,000

in 1859.

The manufactures of lead as disclosed in the census report of 1860 were carried on by fourteen establishments with a capital of $1,739,963, consuming raw material valued at $2,679,453, and paying for labor to 346 operatives $103,056. The product of the last year's operations was valued at $3,166,029, affording a profit of $382,520, or twenty-two per cent. on the capital.

Zinc. While the lead product of the United States has been decreasing, the zinc product has been steadily increasing for fifteen years. Its ores are extensively distributed through the United States and in great abundance, but as yet have scarcely begun to be worked. A variety of ores are worked for zinc ; among these is the sulphuret of zinc or blende, called by the Cornish miners black jack. It is associated with the ores of lead, copper, and tin, and in some mines it constitutes the prevailing ore. The long roasting process necessary to free the metal from sulphur has caused it to be neglected. It lies in immense heaps about many lead mines, awaiting the discovery of some more speedy and economical process of reduction. In England it has become an article of commerce within the last few years, and in France there are five establishments working the same. Red oxide of zinc, found principally in New Jersey, owes its color to the presence of oxide of manganese, as the artificial oxide of zinc is always white when pure. It is found at Franklin and Stirling mechanically mixed with franklinite and associated with calcareous spar. A mass of it weighing 16,400 pounds was exhibited at the Crystal Palace in London. Electric calamine, or the silicate of the oxide of zinc, and other silicates of the metal with smithsonite, or the carbonate of zinc, are found in Pennsylvania, New Jersey, New York, and Tennessee.

Very pure ores of these kinds also exist in Arkansas, imbedded in red ferruginous clay among the magnesian limestones. As a general truth, in the older rocks zinc is mostly associated with the more valuable metals, especially silver and copper. The ores found in such geological positions being sulphurets, are not particularly valuable. The carbonates and silicates, of much greater value, occur generally in calcareous or dolomitic rocks, forming part of or associa ed with the carboniferous system. These deposits are sometimes in beds intercalated in the strata or disposed in irregular masses occupying depressions in

them.

In New Jersey and New York the sulphuret is found associated with galena, copper pyrites, iron pyrites, and crystallized quartz. Zine is found in abun dance in the mines of the western lead region. The silicates and the sulphurets are frequently met with, especially in Wisconsin and Missouri. The manufacture of zinc from these ores against foreign competition is not profitable by the present processes.

According to Whitney, the world's production of zinc in 1853 was as follows: Russia, (including Poland). Great Britain....

Belgium...

....

4, 000 tons, or 7.3 per cent. 1.000 tons, or 1.8 per cent. 15, 000 tons, or 27.3 per cent.

The production of zinc in this country in the following year was estimated as high as 5,000 or 6,000 tons. A single company in New Jersey took from two beds in Stirling Hill, between 1854 and 1860, 30,000 tons of ore. In the Saucon valley, Lehigh county, Pennsylvania, 5,000 tons were mined during 1860. Zine paint, the white oxide, is extensively manufactured in this country. The manufacture of this and other oxides, in 1860, employed five establishments with a capital of $2,228,000, consuming raw material valued at $233,690, paying to 241 hands $87,720, and producing articles valued at $476,860. This leaves a profit of $157,450, or seven per cent. on the capital invested, a remarkable disparity with other branches of manufacture.

Platinum-Traces of this metal have been found in the lead and copper ores of Lancaster county, Pennsylvania, but no grains of the native metal have been discovered north of North Carolina, where a single grain was obtained in Rutherford county, in gold washings. This grain weighed 2.541 grains troy, and had a specific gravity of 18. In California it is found associated with gold, and very frequently rejected by the miners through ignorance of its value. The native gold received at the United States mint at Philadelphia from California in 1852 contained traces of platina, but not enough to pay for detaching it. Gold received from Oregon in 1863 contained an appreciable percentage of platina. In 1850 there were imported 34,000 ounces, worth, at $6 10 per ounce, $20,740.

Still

Iridium and osmium.-An alloy of these metals, called iridosmine, is found associated with native platina. Near Port Orford, to the north of Rogue river, iridium appears associated with gold to the amount of fifteen per cent. further north, between Cape Blanco aud Coquille, there exists an alloy composed of fifteen per cent. of iridium and five per cent. of platinum. Between Randolph and Cape Arago thin metallic scales have been found, composed of seventy per cent. of iridium and six per cent. of platinum. It is used in manufacturing nibs of gold pens, and has ranged as high as $250 per ounce.

Mercury. No deposits of this metal are known east of the Mississippi river. In California, its red sulphuret, called cinnabar, was first discovered on the south side of the valley of San José, about sixty miles southeast of San Francisco. It had been used by the Indians on account of the bright vermilion color it afforded as a pigment to ornament their persons. The Mexicans first worked it to extract gold and silver. In 1850, a company of Mexicans and English engaged vigorously in the extraction and metallurgical treatment of this ore, giving to their mine the name of New Almaden. In eight years they had mined 20,000,000 pounds of cinnabar, and had realized an annual profit of more than $1,000,000, when, in 1858, their proceedings were arrested by injunction from the United States court, on the ground of invalid title. The American parties who succeeded to the ownership extended their discoveries in the same range of hills. In December, 1858, they opened a new mine called Eurequita, the production of which has increased to the utmost limit of their reducing apparatus. The product of these mines in the five years ending with 1858 amounted to 13,318,350 pounds. The ore is found in connection with sedimentary strata, composed of alternating beds of argillaceous shales and layers of flint, tilted at a high angle and much flexed in rocks in close proximity to the tertiary formations. Some writers locate these deposits as high up in the geologic series as the miocene or middle tertiary.

Cobalt. The oxide of this metal is sought after in order to give brilliant

coloringsto glass. The great demand for this article is from the British manufactories of porcelain and stained glass. The ores of cobalt are generally combinations with arsenic, sulphur, nickel, and iron. The chief of these, arsenical cobalt, was obtained at Chatham, Connecticut, as far back as 1787. Pyritous cobalt is found in Maryland, in North Carolina, and Missouri.

Nickel-Metallic nickel, according to Whitney, is confined exclusively to bodies of extra-terrestrial origin, commonly called meteoric iron. These masses often contain a nickel alloy amounting to five or ten per cent. on the whole. It forms several combinations. The principal depository of its ores in this country is at Chatham, Connecticut, where, associated with cobalt, it is found in veins traversing gneiss and mica slate. It also exists in company with copper ores at an old mine lately reopened in Lancaster county, Pennsylvania. This mine in 1859 was producing nickel ore at the rate of two hundred tons per month. A pyritous ore is also found at Mine La Motte, in Missouri.

Coal. The known deposits of coal in the United States transcend in extent and richness those of all the residue of the world combined. The areas of the different coal fields, as estimated by Daddow and Bannan, in their work on "Coal, Iron, and Oil," published in 1866, are represented in the following table:

In 1845 our coal area was stated at 133,000 square miles. It is now known to be over 200,000 square miles, or eight times the known available coal area of all the rest of the globe. The specific areas of the American coal-fields are estimated as follows:

Massachusetts and Rhode Island...

Pennsylvania-anthracite 4,700, bituminous 12,656..

Maryland...

West Virginia.

East Virginia...
North Carolina.
Tennessee

Georgia

Alabama..

Kentucky.

Ohio

Indiana

Illinois

Michigan.

Iowa..

Missouri

Nebraska.

7,700 44,000

13, 000

24,000

21,000

4,000

In addition to the above it is supposed that adjacent to the Rocky mountains there are some 200,000 square miles of lignites, tertiary, and other inferior coals. Another estimate arranges the areas within the ancient Appalachian basin as follows:

Of the American coal-fields the Pennsylvania anthracite, though one of the smallest in area, is now the most copious in production, and the most available to the commercial and industrial interests of the nation. It is arranged in basins as follows:

This production, averaging 20,667 tons per square mile, equals the average of the most productive British coal-field in 1864. Since that time, however, the English coal trade has increased in volume about fifty per cent. English statisticians estimate that their coal resources will be exhausted, at the present rate of production, with an average increase no greater than has been observable of late years, in about three hundred years. Our mining system is not carried on with the close economy of the British mines. With us "the waste is equal to the vend." At least one-third more of the coal extracted from the mines might be made available in the market with a more economical method. Instead of a yield of 60,000 tons per acre, we might reasonably hope for 80,000 or 90,000 tons. The latter aggregate would still leave a mass of 6,780 tons per acre left in pillars and otherwise unavoidably wasted. At the rate of 60,000 tons per acre the anthracite coal-field promises an aggregate of 18,000,000,000

* Daddow and Bannan, in their estimate of the coal-fields of the United States, assign 7,100 square miles to Ohio, 6,700 square miles to Indiana, and 30,000 square miles to Illinois which would reduce the above total to 200,266 square miles.