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A STREAM OF MOLTEN IRON RUNNING INTO THE SAND MOULDS, FORMING THE ROUGH BARS, WHICH, WHEN SOLIDIFIED, ARE TERMED "PIGS."

esota, the Menominee in Michigan and Wisconsin, the Marquette in Northern Michigan, the Gogebic in Michigan and Wisconsin, and the Vermillion in Minnesota.

The iron ore in the United States may be considered in four general commercial classes-red and brown hematite, magnetite, and carbonate. Of these four, the red hematite is the most popular, because of its richness in iron and its freedom from foreign and non-metallic material. These classes are subdivided under various local or trade names.

Three general methods are employed in the United States in mining the oresurface, drift, and underground. In locations where the ore is very hard or lies at a depth of sixty feet. or more from the surface, the latter method is employed. Shafts or tunnels. are driven to the ore beds, which are then worked in a similar manner to coal. In those districts where the ore is found in a loose condition just under the surface, surface mining is almost altogether followed.

Surface Mining for Iron Ore

Where surface mining is employed, the ore must be easy to get at. The top soil is first removed by steam shovels, after

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A MODERN ORE DOCK.

by the numerous steam shovels, is placed directly on specially constructed cars, in which it is hauled to the docks. In this manner immense quantities of ore are obtained at a cost not exceeding forty cents a ton, while the drift and underground require an expenditure of seventy to eighty cents a ton.

The ore ranges of Lake Superior have added more to the economical advancement of American iron than any other single thing. They have given birth to the thousands of miles of railroads that are scattered throughout that district and that devote their entire traffic to the transportation of iron ore. They have added to the Great Lake shipments millions and millions of tons; given employment to thousands of boat builders and crews; forced the Government to make improvements throughout their course; and caused the growth of towns all through the mining districts and the building of the largest docks in all the world.

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Mammoth Labor-Saving Docks

With more than typical American enterprise these docks are built with the latest labor-saving devices. The specially constructed cars are run out upon them, and their hopper floors dropped, permitting the ore to fall into numerous bins below. Underneath and on both sides are long rows of chutes through which the ore passes into the holes of the large ore-carriers. These boats are invariably filled to their very hatches. Over twentyone million tons of ore were transferred through these docks last year. The magnitude of these structures that extend like an immense peninsula into Lake Superior, can therefore readily be imagined.

A large fleet of steamers are constantly plying between their Western docks and the Eastern unloading harbors all during the summer and fall months when the northern Lakes are open for navigation. In winter all shipments are suspended; consequently a large accumulation of ore must always be stored in the East, either at the docks or at the furnaces. Some vessels have a tonnage of six thousand tons, and so perfect are the loading facilities that it seldom requires over five hours to load them.

After a trip through Lakes Superior,

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MOUNTAINS OF IRON ORE IN STOCK AT THE FURNACES. WAITING TO BE CONVERTED INTO PIG IRON.

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ARM AND BUCKET OF ONE OF THE LARGE UNLOADERS IN THE HOLD OF A VESSEL.

Michigan, Huron, and Erie, the immense ore vessels, whether large, ordinary steamers or still larger and strange whalebacks, arrive at one of the many unloading docks of Cleveland, Conneaut, or Ashtabula.

Here, more than anywhere in the world, have the ingenuity and skill of the

THE CASTING MACHINE, The modern method of solidifying the iron.

American engineer been demonstrated, for on every side are the huge yet rapid machines that transfer the ore from the dark depths of the ship's hold to the huge pile on the docks. These monsters of steam or electricity have grown to such perfection and magnitude that the ore boats are rarely held longer than ten hours to have their contents transferred to the storage piles. The boats usually return west with coal as ballast.

As wanted, the ore is loaded into cars, either directly from the steamers or from the stock piles, and transferred by rail to the furnaces. The great Pittsburg district is the destination of the greater portion of this ore. So thoroughly mechanical and free from labor have been these numerous operations of mining, loading, transporting, and delivering the ore in the Pittsburg district, that an expenditure of only two dollars and fifty cents a ton has been incurred.

The greatest advancement which American iron manufacture has made in recent years is in the handling of the raw and finished materials at the furnaces. This is due largely to the great increase of tonnage during the past ten

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