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sure, and render nearly square. After leaving the roughing rollers, the iron is taken to such rollers as will reduce it to the desired shapeif it is to be run into square bars it will pass through the grooves of the flat rollers-if in broad sheets for sheet-iron, it will pass through rollers like those indicated on page 127, or if in small round or square bars, like those of the figure below. For sheet-iron and wire, charcoal iron is always best. In ancient times sheet-iron and other flat iron was hammered out from the blooms by forge-hammers, and then flattened, and the surface smoothed by smaller hammers over the anvil. This method is still pursued in some portions of Europe, where labor is not of as much consideration and value as it is in this country. For this reason we are compelled to resort to machinery whenever it can be done, and hence the proverbial ingenuity of our countrymen, as evinced in every department of the useful arts. The iron to be wrought into broad sheets must previously have been run

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and finally at b, where it is cut off into long thin rods, similar to those used by blacksmiths and machinists. The process is simple. In rolling railroad bars, the ne plus ultra of the art is achieved. The blooms are, of course, very heavy, and the whole process of rolling is on a scale much more stupendous than any other kind of work. The annexed figure shows the gradual transformation of the square billet, when introduced here. It is received at No. 1, and after passing through, is run through numbers 2 and 3. Number 4 presses the bottom and top smooth, and works the bottom flanch down to its

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GROOVES FOR RAILROAD IRON.

proper thickness, and somewhat broader. Nos. 5 and 6 are almost of equal form and size, giving the finish to the rail. The decrement of the grooves is very limited, and there is no difficulty whatever in making a straight rail, even with one groove less. To run the heavy rails through the rollers is, as may well be supposed, a herculean task-but machinery is brought to bear in this, as in every other department of the business. Chains are suspended from sliding pulleys fixed in frame-work over the heads of the operatives, to which huge tongs are attached. These are guided by the workmen, and the long red hot rail is seized and conducted to the groove, where the revolving rollers grasp it. As soon as it appears on the other side, another set of men, with tongs in readiness, grasp it, and immediately return it through another groove. And thus, after five or six passages through the rollers, the rail appears with its péculiar form, and now only needs to be cut off smoothly at both ends, and, if crooked, straightened out, to complete it. The sawing machine, for cutting the ends of the rail,

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is exhibited in the engraving below. The saws are circular, and are put in motion by the straps at a. But one end of the rail is cut at the same time-that done, the rail is drawn under the saw at the other end, and cut off in like manner. Equal lengths are not generally demanded by Railroad companies, hence they are sometimes a little longer and sometimes shorter than the uniform length sought. After the ends are thus cut off, the rail is subjected to a few simple processes to render it perfectly straight, after which the whole work is completed.

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SAWING APPARATUS FOR CUTTING RAILROAD IRON.

The whole number of charcoal furnaces supposed to be in operation in Pennsylvania, is about two hundred and eighty, yielding an annual product of two hundred and fifty thousand tons. The number of anthracite furnaces we estimate at fifty, yielding one hundred thousand tons, making the total of furnaces in the State three hundred and thirty, and the aggregate yield three hundred and fifty thousand tons. Under the tariff act of 1842, the number of furnaces, especially anthracite, increased at a most extraordinary rate-having almost doubled the entire number during the few years it remained in force. The present law, however, has all along operated unfavorably, and while many works have been suspended very few new ones have been put up. There is at this time, however, probably not less than fifteen millions of dollars invested in the production of iron, exclusive of about $6,000,000 invested in rolling-mills, and similar works for the conversion of the metal into forms for use, making the aggregate sum, about $21,000,000. This, we think, is a moderate estimate, based on practical data. The number of persons employed in mining the anthracite and iron ore, is about five thousand; in making the charcoal, fifteen thousand; total, twenty thousand. The number of per

sons directly dependent on this description of labor may be stated at seventy thousand; of those supported by their labor in the conversion of pig iron, ninety thousand; and of the population connected with the production of iron, one hundred thousand-making the total number of persons directly and indirectly concerned in iron manufactures, in Pennsylvania, including miners and colliers, two hundred and eighty thousand. Besides this a large number are employed in the manufactories of machinery; in the transportation, sale, shipment, and other branches of the trade.

We have thus endeavored to present the outline features of several of the more prominent points of inquiry upon iron manufactures. To describe particularly the whole process would require a volume thrice the extent of these pages. To those desiring more elaborate information, and scientific and practical data, we would commend the able work of Mr. Overman, already alluded to, which combines all on this subject that the most practical and curious could desire. Nearly all the foregoing illustrations are copied, by permission of the publisher, from this work: H. C. Baird, Philadelphia.

A short distance from Tyrone station is the celebrated SINKING SPRING, situated in a limestone formation, in the valley bearing the same name. It is an object of great interest, and well deserves a visit from the passing traveller. The spring, where the water emerges, is called Arch Spring, because it rises in a large limestone rock, with a high arch overhanging. As the stream runs along amidst the wildest scenery. it receives additions from smaller springs, when finally the whole volume of water disappears in a large cavern, and again enters the bowels of the earth. In the inside of this rocky cavern the stream continues from eighteen to twenty feet wide. The roof declines as you advance, and a ledge of loose rugged rock keeps in tolerable order upon one side, affording means to scramble along. In the midst of this cave are large quantities of brush, fragments of trees and branches, and such like matter, lodged quite up to the roof, thus indicating that the water, during freshets, is swelled up to the full capacity of its rocky jaws. This opening continues several hundred yards, when the cavern opens into a spacious room, at the bottom of which is a great vortex, into which the water is precipitated, and whirls round with amazing force. The stream is supposed to pass several miles under Brush and Cove Mountains, and to re-appear by two branches, which empty into the Frankstown branch of the Juniata.

Opposite the station at Tyrone, on the left, we have Tussey's Mountain, and on the right the bold ridge constituting the Bald Eagle Mountain, celebrated for its deposits of iron ore. The wholecountry here, however, is filled with iron ore and limestone, with some thin layers of the carbonate of lead, which, many years ago, excited a great deal of attention. A few hundred yards above this station is TYRONE CITY, a sprightly little village, sailing with flying colors under a prosperous breeze. All it wants to become a city in reality, is fair play and plenty of time. It already has the name, and makes a decent exhibit of several brick houses, among which is a hotel, which looks large enough to accommodate a crowd of hungry summer tourists. We say hungry, because we happen to know something about it. Turn a city "pale-face" loose among these mountains, let him ramble boldly amongst the foxes, and snakes, and bears that frequent them, and if he never before knew Appetite, he will soon become familiar with him.

Passing the unimportant stations of TIPTON'S RUN, FASTORIA, BELL'S MILLS, and BLAIR FURNACE, we arrive at the intersection of the branch and main line of the railway at ALTOONA. The branch road extends six miles to Hollidaysburg, where it meets the Alleghany Portage road, already mentioned as crossing the mountain by means of inclined-planes and stationary steam-engines. The main branch. of the Central Railroad, between Altoona on the eastern, and a point a few miles from Conemaugh station on the western slope of the mountain, is still in an unfinished state, but will probably be ready for use in the course of the next ensuing eight months. This road boldly climbs the mountain without the assistance of inclined-planes. The ascent is accomplished in twelve and a half miles, by a maximum gradiate of eighty-four and a half feet on straight lines, reduced on curvatures, according to their diameter, to seventy-five feet upon those of minimum radii. To reduce the elevation to be overcome, from the foot to the summit of the mountain, a tunnel has been driven through it at the highest elevation of the road, which is over eleven hundred yards in length. The elevation of this tunnel above tide-water is nearly twenty-two hundred feet! The whole distance across the mountain from Altoona to CONEMAUGH station is about thirty-five miles, or about the same distance as the present Portage Railroad with its ten inclined planes!

A brief description of this road, or some of its most prominent

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