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ica the furnaces usually contain from four to ten holes, six pots being placed in each, three abreast and two deep. The pots rest upon a thick layer of coke dust, which is able to withstand a very severe heat without becoming spongy or liquid, the coke dust making a very firm yet easy rest for the pots. Each hole is provided with three covers, which are easily removed by means of a lever.

The furnace being thus charged, and the covers placed over the holes as closely as possible, the gas and air are permitted to enter. Rushing through the superheated chambers on one side of the row of holes, they meet and pass through the flues into the furnace.

Darting around the pots, this heated gas, which rises in temperature to about 3,000 F., finally passes through the opposite flues into the chambers on the opposite side. Circulating through these and thoroughly heating the same, it finally passes up the stack.

The pots are subjected to this terrific heat for two and a-half to three hours, when the melter, by means of an iron rod, pushes the caps of the pots aside to ascertain whether the mass is melted. When melted it is still left in the furnace, in order to boil out any gas which might be held in solution. This is termed "killing" or "dead melting." Having been "killed," the molten steel is ready to be

cast.

How the Workmen Make Ready

In preparation for this work of casting, the men wrap their legs with carpets, rubber, etc., and soak themselves with water. The cover is drawn from one of the holes; and the "puller out," dressed as above described, stands over the furnace or hole, and by means of a pair of tongs pulls the pots out, one at a time, carrying them to the moulds, which are standing in the casting pit at the end of the floor. There the molten steel is poured into the moulds, which stand upright. As a rule, the moulds are of onepot capacity; but, if larger ingots are desired, larger moulds are employed, the metal being obtained from several pots. - Care is taken that the stream from the two pots is not broken, the liquid flowing

continually. If this is not done the result will be a defective ingot.

The pots, if in good conditior, are refilled, and placed back in the furnace. When the steel in the moulds has solidified, the moulds are unfastened and the hot ingots drawn out, ready for another department.

Handling of Crucible Steel

The ingots are first taken from the casting pit or furnace to the "tempering" department. Here, by means of a sledge, the top or piped end of each ingot is knocked off in order to expose the grain of the steel, thus permitting an experienced eye to ascertain the carbon percentage of the same. In mild ingots, and those of a shape or size that will not permit of the ends being removed, a small corner of the ingot is chipped off.

The formula being marked upon the ingot, indicating the grade and the percentage of carbon, the ingot is then either piled in stock or taken directly to another department. Unlike the products of other processes, many grades of crucible steel are first welded-hammered at a high heat-thus refining the grain and destroying many of the blow holes or gas holes. The steel is then usually taken directly either to the hammer shop or to the mills. In either case the billets are reduced to the desired shape and size by being passed between rolls or under the rapidly moving dies of the steam hammers. The completed billets go to the "inspection house," where every bar of steel is examined minutely for all defects. before being weighed, marked, and shipped.

The Open Hearth Process

The open hearth process furnishes about one-third of the steel used to-day. It has, for the past few years, been rapidly crowding Bessemer steel out of the market, as well as making great inroads in the fields formerly occupied by the crucible product.

The cause of this popularity, on the one hand, is that the stock, in many cases, is much sounder and gives better satisfaction than Bessemer-which naturally justifies the small additional expense. On the other hand, experiments

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FILLING THE BESSEMER CONVERTER WITH WHITE MOLTEN IRON, TAKEN DIRECTLY FROM EITHER THE BLAST FURNACE OR THE CUPOLA.

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A PIECE OF WHITE-HOT STEEL, WEIGHING 6,000 POUNDS, ENTERING THE ROLLS.

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RAISING A WHITE-HOT PIECE OF STEEL FROM THE SOAKING PITS BY MEANS OF A POWERFUL ELECTRIC ARM.

This giant hydraulic crane, clutching in its jaws the white-hot ingot of steel, well illustrates the titanic apparatus used in great steel mills. In comparison with the enormous weights to be lifted and the tremendous heat to be dealt with, man is so puny that, of necessity, almost everything must be done by machinery, human fingers being necessary chiefly to raise and lower the levers and press the buttons which set the great machines in motion.

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