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appears to be the best located of the three works. The Western Works enjoy the advantage of a very cheap and good ore, a true argillaceous ore, somewhat calcareous, which, in most cases, is laid, at the furnace, at from one dollar to one dollar and twenty-five cents per ton. With charcoal, this ore produces an excellent and strong metal; and many expensive experiments were made with this ore before coke furnaces were brought into a state adapted for regular business. Still, it appears almost impossible to run these furnaces upon gray iron. A whitish, red-short forge pig is the quality constantly manufactured. On what hypothesis this is to be accounted for, we shall hereafter endeavor to explain.

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Coke furnace, Great Western Iron Works, Pa.

Fig. 61 exhibits a section across the work arch and the back arch, including the bridge-wall of a great western furnace. There

is scarcely any, or at least a very low, and considerably tapered, hearth in the furnace. The boshes reach down almost to the tuyeres, and that part alone below the tuyere is plumb. The furnace is provided with six tuyeres, and with hot blast. It produces from seventy to eighty tons of forge iron per week. The lower part of the boshes, which in other furnaces forms the hearth, is about six feet high. This part is made of sandstones from the coal measures; but from this point till it joins the in-wall, it is made of fire brick. In other respects, this furnace does not materially differ from other furnaces.

VII. Hyanges Furnace.

At Hyanges, Department Moselle, in France, there are three beautifully constructed blast furnaces for coke, which work admirably. Fig. 62 shows a section across timp and back; and Fig.

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Section of a coke furnace at Hyanges, France.

63 a front elevation. The stack is forty-six feet in height, and it measures sixteen feet at the boshes: height of hearth six feet, and width of top eight feet. The exterior of the furnace is round;

the rough wall rests on cast iron pillars, and cast iron framework. It is built of hewn sandstone, finely dressed, and bound by wrought iron hoops. The in-wall is made of fire brick; the hearth, of a cement composed of roasted and pounded quartz, mixed with fire clay, and pounded in between the cast iron plates, which form the cloak of the hearth; the boshes are formed of fire brick, made of ́the same material as the hearth, and air dried. The damstone is not in a sloping position, as usual in furnaces; but a vertical dam of fire brick is erected, in the middle of which holes for tapping

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Front view of a coke furnace-Blast furnace at Hyanges.

the iron are left. The dam-plate is protected from the overflowing hot cinders by a projecting rib on the top. In these furnaces, brown hydrates, very much resembling the fossiliferous ores of Eastern Pennsylvania, are smelted. The metal produced is very cold-short; but it is wrought into bar iron of the finest forms and shapes. A large amount of it is converted even into sheet iron and tin plates. We shall have occasion to refer to this subject again. In the chapter on puddling, we shall explain the exact process by which this metal is converted into bar iron.

As we have previously remarked, there is but little prospect of seeing coke furnaces in successful operation in the United States. Nearly every State in the Union has good raw coal in sufficient quantity, as well as of proper quality, to supply its furnaces. Whatever else is necessary to be said on the subject will be found in our general review of furnace manipulations.

VIII. Stone Coal Furnaces-Anthracite Furnaces.

If the use of coke in blast furnaces has, from various causes, been exceedingly limited in the United States, raw coal and anthracite have been employed to a degree which the most sanguine could scarce have conceived. In Eastern Pennsylvania, more than sixty blast furnaces, supplied by anthracite, are, at the present time, in operation. These produce, on an average, from seventy-five to eighty tons of iron per week. In addition to this, many furnaces are now in course of erection. This immense number of furnaces, supplied by stone coal alone, is the result of the last ten years' industry. The perfection to which these have been brought is a security that nothing can check their prosperity, or prevent their extension in this country.

It is not our purpose to present an elaborate history of anthracite furnaces, or to show to what extent anthracite is employed in the manufacture of iron. Those who wish information on this subject may gratify their curiosity by referring to Prof. Walter R. Johnson's Notes on the Use of Anthracite, &c.

a. Anthracite furnaces resemble, to a greater or less degree, coke and charcoal furnaces. They are seldom so high as coke furnaces, and their horizontal dimensions are usually greater than those of charcoal furnaces. To avoid unnecessary repetition, we shall give the dimensions of several of these furnaces recently erected in Eastern Pennsylvania. Fig. 64 represents a cross section of an anthracite furnace at Reading, belonging to Mr. Eckert. Its height is thirtyseven and a half feet; the top or throat six feet in diameter: height of hearth five feet; tuyeres twenty-two inches above its bottom: the hearth is five feet square at the base, and six feet at the top. The boshes are inclined sixty-seven and a half degrees, or at the rate of six inches to the foot, and measure fourteen feet at their largest diameter. At the point where the slope of the boshes joins the lining, a perpendicular, cylindrical space, five feet in height, commences; from the latter point the general taper to the throat is continued in a straight line. The hearth, as well as the boshes, is built

of coarse sandstone; but the latter are covered with a lining of fire brick nine inches thick. The in-wall consists of two linings;

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the interior is the lining which covers the boshes: outside of this is a space four inches wide, filled with coarse sand; and this is protected by a rough lining of slate, two feet thick. The rough walls of the stack are not heavy; but they are well secured by binders.

b. Two furnaces lately erected at the Crane Works, near Allentown, may be considered the latest improvement. (Fig. 65.) The stack is thirty-five feet high; forty feet square at the base, and at the top thirty-three feet. This furnace is, therefore, but slightly tapered, and requires heavy stonework. It generates steam from the trunnel head gas flame. At most anthracite furnaces, this is done by putting the boilers on the top of the furnace. The hearth is five feet high, four feet square at the bottom, and six feet at the top; the inclination of the boshes is 75°, and the cylindrical part of the in-wall above the boshes is eight feet high, and twelve feet in diameter. From the cylindrical part up to the top, which is six feet in width, the in-wall runs in a straight line.

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