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In the general arrangement of the Universal Exposition of 1867, iron and steel, as products of industry, were placed in the fortieth class of the fifth group. In the distribution of the work of the Commission of the United States, made in conformity with the directions of the Secretary of State, a committee was constituted on “Metallurgy and the extractive arts in general,” and to this committee was subsequently assigned, by resolution of the commission, the duty of reporting on “Minerals, as raw materials in the economic arts." The committee consisted of Cominissioners Hewitt, D'Aligny, and J. P. Lesley. To Commissioner Lesley was assigned the task of reporting upon “Mining machinery and processes of mining;" to Commissioner D’Aligny, on “Minerals, as raw materials in the economic arts, and on the metallurgy of the precious metals;" and to Commissioner Hewitt “On the production of iron and steel in its economic and social relations."

In the preparation of this report, in order to bring it within reasonable limits, the general principle has been adopted of attempting only to describe specimens of material, machinery, and processes of manufacture which differ substantially from the experience of the United States; thus presenting, as far as practicable, a purely differential report upon the iron and steel of the Exposition. The necessity for this course will be apparent from the mere statement that the catalogue of class forty includes 2,395 entries, of which the far larger portion are produced in the United States of equal quality, and by processes equally economical. The exhibition of the United States, however, was of so meagre a character that foreigners, judging from the lessons of the Exposition, would have come to the inevitable conclusion that the iron and steel industry of the United States is not entitled to the rank which it undoubtedly occupies in the metallic production of the world. The various ores mainly used in the manufacture of iron in the United States were indeed to be found among the minerals exhibited from the primitive regions of Lake Superior, New York, and New Jersey, while the brown hematites of Connecticut, Pennsylvania, and Alabama, together with the red fossiliferous ore of Tennessee and Alabama, and a brochure published by Mr. Haines, agent of the State of Alabama, were sufficient to call attention to the unequalled resources of the United States for the foundation of an iron industry which, under equal conditions as to the price of labor, would soon be in advance of that of any other nation whatsoever. A single piece of spathic ore, from Connecticut, and a few pieces of franklinite, from New Jersey, alone served to indicate the possession of the indispensable material upon which the production of Bessemer steel, as at present practiced, is based. A few pieces of pig iron from Lake Superior, from Wisconsin, Ohio, and Alabama, and some inconsiderable specimens of wrought iron, made from the Lake Superior and the Alabama pig, were the sole indications of an annual production of more than a million tons of iron. The only proof of the existence of any manufacture of steel in the United States was contained in a case of very beautiful specimens contributed by Park Brothers & Co., of Pittsburg, for which they received a silver medal. There was no evidence in the Exposition of our large and increasing product of bar iron, of the rolled girders-in the manufacture of which we preceded the world-of the cut nails, of which we enjoy almost a monopoly, and of the infinite variety of wrought and cast iron, in the skilful production of which we are not surpassed by the most advanced nations of Europe. On the other hand, there was a marked superiority in the products of the European makers designed for uses requiring difficult shapes-a requirement met in our country either by welding or riveting pieces together, and which in Europe, at the present time, seems to be almost universally supplied by material of such admirable quality as to admit of being forged or pressed into the most intricate and unusual forms. Such articles as deeply-dished boiler heads, steam domes, tube sheets, and even culinary vessels of every form and variety, and many other articles of fancy, designed merely as tours de force, such as cocked hats, and series of square domes raised from a flat plate, were exhibited, made from a single piece without weld or joint. Nor was this evidence of peculiar excellence confined to any one country. In France, the works at Le Creusot, Chatillon, and Commentry, and those of Messrs. Petin, Gaudet & Co.; in England, the Bowling and Low Moor Works, and those of the Earl of Dudley; in Prussia, the works of A. Borsig, near Berlin, and of Hoerde; and, in Austria, the imperial works at Neuberg, may be enumerated, among others, as having exhibited material of such remarkable quality as to open an entirely new field for the application of iron and steel.

Again, there was unmistakable evidence in the Exposition of the readiness of the European ironmasters to grapple with difficulties in the way of rolling shapes, from which at present the American maker would shrink. For example, Messrs. Petin, Gaudet & Co. (France) exhibited a rolled beam of the depth of 1 metre, (393 inches,) in length 9.72 metres, (over 32 feet,) and weighing 24 tons. They also exhibited another beam weighing 2.3 tons, 12 inches in height, and over 106 feet in length. The works of Chattilon and Commentry exhibited a beam 434 inches in height,

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and with a 12-inch flange, but of very moderate length; but another beam was exhibited, about 100 feet in length, 9 inches high, weighing about fifteen hundred weight. The Burbach (Prussian) works exhibited a rolled beam 47 feet long and 15 inches in height. A careful observation, however, of the various structures in process of erection on the Continent, failed to show that these remarkable specimens of rolling had yet been brought within such limits of cost as to admit of their use in building. In the Exposition building itself, no rolled beams were to be found of a greater depth than 9 inches, and in the innumerable buildings which are being erected in Paris, and in which iron beams are invariably employed to the exclusion of wood, 4 inches, 6 inches, and 7 inches are the dimensions most generally employed. Thus far the construction of a fire-proof building in the United States is accomplished with less pounds of iron for a given strain per square foot than in France, and we have nothing to learn from the Exposition in this respect. But now that it has been found possible to produce beams of such large dimensions by the simple process of rolling, it is but reasonable to expect that the cost will be reduced as experience is gained, and that they will gradually replace the riveted girders, which even in the palace of the Louvre are invariably employed for spans of any considerable extent. It is proper, however, to call the attention of our American makers of rolled beams to the extraordinary specimens which we have described, and which it is understood are produced by the aid of the universal rolling mill.” Of this two forms were on exhibition, one in the pavilion of Chatillon (France) and the other in the Austrian department. The latter consists of four rolls, in two pairs, working at right angles to each other, a description of which, illustrated by engravings, can be found in Colburn's Journal (Engineering) for May 24, 1867. Of the mill at Petin, Gaudet & Co.'s no model was exhibited, and no description of it was given in the documents furnished to the commission.

By a personal visit to the works, however, the construction of the mill was seen to be very simple, and not remarkable for novelty. For each size of beam there is a pair of rolls, each having a working face at the middle of its length equal in width to the depth of the beam. The diameter of the roll at this part is very large, say 3 feet 6 inches, the body of the roll for the rest of its length being about 22 inches diameter. This formation of the rolls leaves a considerable space between the two, except where the working faces come together. In this open space is placed a pair of rollers, working on vertical axes fixed in stout movable frames, by which they can be brought into juxtaposition with that portion of the horizontal rolls which is of largest diameter. The pile used is somewhat thinner than the width of the flange to be produced, and of a width somewhat greater than the depth of the beam, and is so made up as to conform roughly to the final shape of the girder. As the main rolls are brought together, and form the trough in the beam, the friction rollers at the sides are also pressed towards the centre, and tend, by the pres

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