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should enter into a national work. It can afford no facilities for the settlement of the extensive region lying between the States and the Pacific ocean. Indeed, the projectors seem studiously to avoid entering upon the territory belonging to the United States; and if their road should be built upon the line contemplated, it will not satisfy the demands of commerce, or the social wants of a large portion of the American people. Consequently, if a practicable route should be found farther north, the Government will be urged and compelled in time to make an appropriation for a second route. This state of things should be guarded against; and may be avoided by the construction of a great trunk line, to be located as near the center of our own territory as the physical character of the country will admit; and in favor of such a route we earnestly invoke the co-operation of all who desire to promote the commercial prosperity and moral grandeur of our broad republic.

ARTICLE II.

[From the Mining Magazine.]

Iron and Zinc.

MANUFACTURE OF IRON FROM LAKE SUPERIOR ORES.

To W. J. TENNEY, Editor of the Mining Magazine.

I will give you my impressions regarding the iron region and the manufacture of iron from the Lake Superior ores, though I have hitherto avoided giving publicity to opinions opposed as mine have always been to the popular and extravagant statements, that have been spread abroad through the papers on this object.

The Lake Superior iron ores belong to the variety of ores known as specular iron-a combination of iron and oxygen, of which the metallic proportion cannot exceed by weight seventy-two and a small fraction per centum. Magnetic iron ore accompanies the specular, and the two are frequently mixed. The greatest proportion of iron ever obtained from this mixture cannot exceed seventy-five per centum. No reliable analysis of the Lake Superior ores has ever given so high a yield as this. Statements of a greater yield prove their own falsity, and the ignorance of the operator. Such ores are not peculiar to the Lake Superior region. are almost or quite as abundant in Missouri; and similar ores are extensively worked on the shores of Lake Champlain; in Orange co., New York, and in New Jersey. New Hampshire and Georgia, both contain in mountain masses varieties little differing from them.

They

Some of the Andover ore of New Jersey cannot be distinguished from the choicest of the Lake Superior ores; and if made into bar iron direct, with the same care as were the samples for trial prepared from this ore, there is no question but it would exhibit the same remarkable strength; the pig-iron manufactured from it, though made with anthracite, possesses the strength of the best charcoal iron.

Being very free from earthy matters, these ores are well adapted for working in bloomery fires. They require a preparatory roasting, stamping and screening, by which they are subjected to some loss, and finally yield about a ton of metallic iron to two of ore as taken from the mine. More or less is lost in the cinder, according to the skill of the workmen, the purity of the ores and the adaptedness of the apparatus.

The bloomery process is a convenient one, where the ores are of this rich character, and charcoal is abundant. The charcoal made from the hard maple and birch of this region, is especially well adapted for this process. It is of remarkable soundness and density, owing to the great hardness of the wood. The same cause adds materially, however, to its cost. Each bloomery fire, worked by two bloomers and two ordinary workmen, turns out about a ton of blooms in twenty-four hours. The wages amount to eight dollars, and the consumption of coal, including waste, and all really paid for, can seldom be estimated at much less than 300 bushels. Of the charcoal, such as I saw at the works, 250 bushels ought to be enough. The expenses of manufacture may then be estimated as follows:

Estimated cost of a ton of blooms made on the Lake Shore. 2 tons of ore, quarrying and hauling 12 miles, at $2...... $4 00 Roasting same, at $1 ........

Stamping and screening, at 50 cents

250 bushels Charcoal, at 8 cents (actual cost) ...

2 bloomers at $3, 2 helpers at $1, or same amount as by

actual contract......

Repairs $1, Superintendence $1, Interest $1..

General Expenses...

Cost on Lake Shore.....

200

1 00

20 00

800

3 00

2.00

$40 00

Shipping, freight, carting, storage and commission, say... 15 00

Cost when sold at Cleveland.................... .$55 00 This cost calculated upon a small operation, with large allowance for transportation, may be considerably reduced by running twenty or thirty fires in the same establishment, and by the construction of a rail or plank road from the mines to the Lake shore. But there are several points requiring careful consideration before one could be justified in pronouncing upon the success of such an undertaking. In the first place, no business is so wholly in the hands

of skillful workmen as that of manufacturing blooms. For every ton made in twenty-four hours, two men are required, who have served a regular apprenticeship, and acquired their ability only by long practice. Their places cannot be filled with men picked up any where. The success of the business is dependent wholly upon their skill and good will. Strikes are common among them, and are frequently disastrous to the works. This is especially to be feared in a remote district, shut off a large portion of the year from all communication with other places where this manufacture is carried on. It is probable that this cause, more than any other, has kept back the spread of large bloomeries in New York and New Jersey, and limited the business, with few exceptions, to small works, conducted by the proprietors, who were once bloomers themselves.

Again to carry on a large establishment, powerful machinery is required, and this must be kept in steady running order. But such machinery is liable to accidents and breakages, to repair which recourse must be had to complete machine shops, foundries and large forges. Now these must either be provided at the works, and competent mechanics kept employed at them, or delays of a whole winter may be involved.

Then again, for six or seven months in the year the products of the works are accumulating without a possibility of getting them to market. Opportunities are lost of taking advantage of high prices. The capital lying dead, adds materially to the expenses.

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Such considerations as these, together with others arising from the great expenses of introducing and supporting the population required for carrying on this business at Lake Superior, have led me to look with incredulity upon the large estimates of profits to arise so soon from the manufacture of blooms in this region.

Still I am very far from questioning the great value of these rich ores-with few exceptions the only iron ores from the country east of the Alleghanies to the Mississippi River, north of Tennessee, that have been or will be discovered, suitable for the manufacture of the best boiler-plate iron, wire, car-axles, car-wheels, and other work of refined or cast-iron, requiring the greatest strength. The demand for them will be immense. The great Lakes already craw enormous supplies of iron from the eastern portion of the Atlantic States; much of the best of it, after it had passed through the mills at Pittsburg, and been mixed and deteriorated with the poorer western iron; some of its supplies have crossed the Atlantic, and in the state of Scotch pig finds no serious competition in Wisconsin and Illinois, after having passed around a fourth of the circumference of the globe. The Lake Superior mines are destined to change the course of this trade, and supply better iron than is now generally found about the great Lakes. But can this be done by a process which requires the slow labor of four men to make a ton of iron in twenty-four hours, besides all those employed

in the various other departments of the work? For many purposes, iron made direct from the ore will be preferred to that first made into pig-iron and then refined; and the comparatively small quantity so prepared will find a profitable sale in a prosperous state of the iron market. But the great demands of the trade must be met, as they are now, by iron produced from blast furnaces. It is the establishment of these, judiciously located, in connection with large rolling mills, forges, nail factories, &c., that will first really develope the resources of the iron region, and realize the profits that its mines are capable of producing.

To work these ores successfully in the blast furnace, they require mixing with other leaner cres. It may be there are varieties in the same region, that will bring down the percentage of the whole to about 50 of cast iron, and afford the materials (with such limestone as is already discovered in the country, or may be carried there as return freight,) for a fluid-running, glassy cinderthe first requisite in making pig- iron. It is more likely the country below can furnish a better variety of these poorer materials. In the same way the ores of Lake Champlain are now most advantageously worked on the Hudson river, where they meet other primary ores from the Highlands and the hematites of Massachusetts and Connecticut.

By the mixture, made with judgment, the objectionable qualities of one kind are neutralized by the opposite qualities of the others, which by themselves would be equally objectionable.

In this way the poor ores are made profitable, and produce good iron. So the bog ores of lower Michigan and Ohio, and the clay iron-stones of the coal formation may be turned to good account worked with the rich ores of Lake Superior; and according to the different mixtures many desirable varieties of iron may be obtained.

The canal past the Saut once completed, the expense of transporting the ore below to be there smelted, seems to be of little moment in comparison with the expenses and difficulties consequent on the running of blast furnaces in the upper country. These in their present improved construction and heavy machinery, are still more dependent than bloomeries for their uninterrupted running, which is essential to their success, on convenient access to machine shops. This is one reason why they are now more generally found close to large cities, than as formerly in remote districts, near the mines. Here, too, the works are at all times sure of workmen, and the proprietors are not compelled to clear lands, build houses, cultivate farms, and import stock and other supplies for their support. At all times they are under the eye and control of the parties interested. The products of the works are at once in the market, and they are varied to meet the immediate demand. This ability to fill orders is almost as essential for the complete success of blast furnaces as of rolling mills. It is not improbable that the additional cost of transportation of ore (to Detroit for in

stance), would be more than met by the cheapness of charcoal, which must always be obtained on the shores of the lower lakes. In Baltimore there are seven or eight blast furnaces, all of which are supplied with fuel brought to them from the wooded country around Chesapeake Bay. Lake St. Clair, in this respect, is to Detroit what the Chesapeake is to Baltimore. Wood to both is furnished for about two dollars per cord and no fears need be entertained that the supplies will ever be exhausted. The wood is brought to the furnace dock and charred in kilns containing from fifty to sixty cords each. At two dollars per cord, charcoal will cost, thus prepared, less than six cents per bushel. The vast country supplying the wood keeps up a healthy competition; the supplies are certain, and there is little variation in the prices. To one familiar with charcoal furnaces, and the great difficulty of stocking them, this will present itself as a consideration of the highest importance. It would certainly debar any prudent man from rashly attempting to make pig iron in the lake country, with its present population.

At all well managed blast furnaces, it is customary to keep a large stock of ore on hand. It is benefitted by lying a year exposed to the weather. There is hence no unnecessary use of capital in getting down during the summer the ore for a year or more, as there is in keeping a winter's stock of iron on hand in the upper country.

Many people have a mistaken notion that the best iron can only be made direct from the ore; others, that charcoal iron made with cold blast is the only pig-iron suitable for making the strongest refined iron. Yet the hot-blast iron of the Housatonic valley has always found a good market at the forges where car-axles are made, and it is selected for the bars which Collins orders for his axes, and which, perhaps, are as carefully scrutinized and subjected to as severe tests as iron for any other purposes. And so great are the modern improvements in the manufacture of pig-iron, even that made with anthracite from the Andover ores and puddled, produces bar iron little inferior to the best charcoal blooms. There can, therefore, be no reasonable objection to werking the Lake Superior ores in charcoal blast furnaces, on the score of their making poorer iron. Though success has not attended the attempts to use our bituminous coals for making pig-iron on a large scale, there is more reason in looking to these as the fuel that will probably be hereafter employed for the reduction of the Lake Superior ores, than now to find fault with charcoal furnaces.

As the iron business is now conducted, the profits of the smaller establishments bear no comparison with those laid out on a liberal scale-supplied with the most thorough machinery, and of the latest and most approved designs. The size of the furnaces has greatly increased the last few years, and the production of some of them has far exceeded in proportion, their increased capacity.

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