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regarded as a very large amount. The gradual increase in yield in different districts is certainly one of the most interesting points connected with the development of the iron trade in modern times. Not many years ago, a weekly return of 70 tons was considered good, but now a single furnace has yielded the enormous amount of 600 tons in a single week. Some of the Aberdare furnaces are reported to have done excellent work, and to have yielded a weekly average of 400 tons. This has been effected by what is called "driving hard "-i.e., sending a large quantity of blast through the furnace in a given time. Great yields have recently been obtained at the Barrow-in-Furness works, Cumberland. These works are quite of recent construction, and were represented by a costly mahogany model, occupying a very large superficial area. There was also a single model, made to open, of one of the furnaces. The average yield in one of these furnaces per day during the fortnight ending the 16th of April, 1862, was 91 tons 7 cwt. 3 qrs., or the enormous amount of about 640 tons (short weight) in a week of seven days. In one week this furnace yielded not less than 684 tons (short weight)! The qualities of the pig iron were 3.5 between Nos. 1 and 4, and 2.5 between Nos. 5 and 6, inclusive of 35 tons of mottled pig. It is exclusively rich red ore that is smelted at these furnaces, and the fuel is Durham coke. Gases are economized in raising steam, and their propulsion to a distance is aided by the exhaustion of a fan.

In the Austrian Department Charcoal Pig iron was shown; it is produced with a consumption of less charcoal than is known in any other locality. The ore is brown decomposed spathose ore, containing, when roasted, 52 per cent. of iron, and the products are gray iron and spiegeleisen. Only 60 parts by weight of charcoal are required to produce 100 of pig iron. Models of furnaces for smelting iron and copper were found in the Russian Department. They are long and rectangular in horizontal section, and are provided with numerous twyers. One of those furnaces is reported to have been in operation for smelting iron during a year and a half. A large yield and reduction in the amount of fuel are stated to be the advantages of this kind of furnace.

Forged Iron.-Some of these specimens were interesting as illustrations of remarkable malleability, others as displaying skilful workmanship, and others on account of their large dimensions. With regard to forgings remarkable on account of their large dimensions, the two objects which stood out preeminently were the enormous Crank Shaft and the large Armor Plate manufactured by the Mersey Steel and Iron Company. The monster shaft weighs about 25 tons, and is destined for one of her Majesty's ships. During the process of forging, this heavy mass was moved by powerful and skilful mechanical appliances, with ease and rapidity, just as a blacksmith handles his iron.

The plate bears the following inscription:"This Armor Plate, 21ft. 3in. long, 6 ft. 3 in. wide, 5 in. thick, having a superficial area of 133 feet, weighing upward of 13 tons, was forged at the Mersey Steel and Iron Works, Liverpool, and has been neither smithed nor tooled since it left the steam hammer. This plate would have been made 15 ft. to 20 ft. longer if space could have been obtained." _It is an admirable specimen of forging. The great Horsfall Gun, of which every one has heard, is another testimony to Mr. Clay's (the manager of the company) skill in forging large masses of iron. This gun was made several years ago: it is 10 in. in the bore, and has stood charges of 80 lb. of powder.

Welding. The Exhibition contained many very interesting illustrations of Welding under difficult conditions. The Butterley Company's large girders, of which one was in the form of a double T, 12 in. across each end and 3 ft. deep, was welded longitudinally. In the English Department was shown a stamped, solid, wrought-iron wheel, made by an ingenious process invented by M. Arbel, a Frenchman: it was forged under the steam hammer, and combines strength and cheapness. In illustration of the successful welding of steel and iron in railway tire bars, we may refer to the specimens of the Monkbridge Company's collection. The iron tire being heated to whiteness, and dusted over with borax powder, the melted steel is cast round it: the union seems to be perfect, and we have examined specimens which have been hammered out into thin plate without presenting any sign of separation. This process is also the invention of a Frenchman, and promises well.

The French appear to have made great progress in the manufacture of iron, and we are indebted to them for many ingenious mechanical contrivances. Two instances in the case of railway wheels have just been mentioned, and to these might be added a third-the process of Pétin, Gaudet, and Co., of making "weldless tires," of which the Blaenavon Company exhibited specimens manufactured by themselves.

Rolled Iron.-Specimens of Boiler Plate were shown, doubled hot and doubled cold, and punched under various trying conditions. The Butterley Company exhibited a Rolled Boiler Plate, 12 ft. 9 in. long, 7 ft. 6 in. wide, and 11 in. thick. The solid-rolled Engine Beam Slab well deserved attention: it is 31 ft. 6 in. long, 7 ft. wide in the middle, 2 in. thick, has a superficial area of 163 square feet, and weighs 7

tons.

Sheet Iron.-Of sheet iron there were numerous fine illustrations. The Belgian sheets were, of their kind, unrivalled, and were specially characterized by their smooth and dark bluish gray glossy surface. The color is obviously due to a thin and firmly adherent skin of oxide of iron, which has been detached here and there near the edges of several of the

sheets, clearly revealing the color of the subjacent iron. Russia still continues without a competitor in the production of a peculiar description of sheet iron, which has long been highly esteemed in commerce. The quality of the iron, which is both smelted and worked with charcoal throughout, is excellent, and the dark polish on the surface is remarkable. Austria exhibited excellent sheet iron, and so did the Zollverein, except the specimens of the so-called transparent iron, which are a sham. This iron is not transparent at all, but is perforated with innumerable small holes through which light passes, thus showing how inferior in malleability iron is to gold.

Bars, Rails, and Girders.—This display was magnificent; and in no branch of the metallurgy of iron has greater progress been made since the first Exhibition of 1851. The mill power required to produce some of these articles is enormous, but we are probably far from having reached the maximum limit. There were gigantic rails exceeding 100 ft. in length, but these were to be regarded as curiosities, interesting as exhibitions of power and effective mechanical appliances, showing what might be done if required. In general they were admirable specimens of rolling. The Butterley Company sent a Rail 117 ft. long, aud 5 in. deep, and a Tension Bar for Girders, 83 ft. long, 1 ft. wide, and 1 in. thick. The Dowlais Company exhibited two rails of the following dimensions: one 53 ft. 6 in. long, 4 in. across the head, and 10 in. deep, the other 31 ft. 6 in. long, 5 in. across the head, and 15 in. deep. In the Zollverein was a section of rolled rail 5 in. across the head, and 18 in. deep. Belgium made a very creditable show of rails and rail sections; and it is declared that in certain foreign markets she has beaten the English producer of rails, both with respect to quality and price. The Austrian Society of State Railways exhibited specimens of railssome with the head of granular and the foot of fibrous iron, and others of puddled steel.

Dupont and Dreyfus (France) exhibited a fine and extensive collection of objects of interest, especially with reference to building constructions. There were flat bars and girders in great variety and profusion, indicating excellent workmanship. In France iron is extensively used for building purposes, and is applied with much science.

The Bridge-links for Suspension Bridges manufactured by Howard, Ravenhill and Co., Rotherhithe, were interesting as having been made by rolling. One of the links exhibited weighed 6 cwt. From the time the slab left the furnace to the complete formation of a large link about four minutes elapsed.

Armor Plates.-There were no metallurgical illustrations in the Exhibition of more interest than the rolled Armor Plates for ships. Of these two were sent by John Brown and Co., Atlas Works, Sheffield. The immediate dimensions are as follows:-(No. 1) length 21 ft.

8 in., width 4 ft. 2 in., thickness 63 in., weight 10 tons 12 cwt.; (No. 2) length 24 ft., width 3 ft. 8 in., thickness 5 in., weight 7 tons 17 cwt. A few years ago the rolling of such enormous masses of iron would have seemed incredible. Brown and Co. also exhibited large, but much thinner plates outside the building in Exhibition-road; one was intended for gunboats, and is 22 ft. long, 7 ft. 2 in. wide, and 2 in. thick; and the other for engine beams. These two plates were thus manufactured. consisted of "best new scrap," obtained from a mixture of Swedish, Shropshire, and Derbyshire refined iron. It was balled under a 4-ton steam hammer, piled under a 6-ton helve, and rolled into bar, re-rolled into slabs, all crossed, then rolled into "moulds," and lastly, rolled into the finished plates. There are 360 layers in the 6-inch plate.

The metal

The Butterley Company sent two Armor Plates, each 14 ft. long, 5 ft. wide, and 4 in. thick, and weighing when finished six tons. The expense of manipulating such enormous masses of iron as these armor plates is necessarily very great; and the present cost of them to the nation ranges between £35 and £45 per ton!

Canadian Iron.-Enormous deposits of magnetic iron ore-which, when pure, is the richest of all the ores of iron-have been discovered by Sir William Logan in the Laurentian rocks, which present no traces of organic remains, and are the oldest sedimentary series in the world. The ore occurs interstratified with the rocks containing it. The accumulation of this ore in some localities is so great as to appear incredible. Thus, one bed is not less than 500 feet thick! On the Rideau Canal there is another bed 200 feet thick, which is now worked at New-. borough, and from which the ore is conveyed to Kingston on Lake Ontario. Canada also possesses extensive tracts of bog-iron ore on the north side of the St. Lawrence. Cast iron from ordinary bog-iron ore is about the last kind of metal many founders would dream of employing for such a purpose; yet in the Canadian Department was exhibited a pair of Railway Wheels which have travelled, without showing much evidence of wear, not less than 150,000 miles, or about six times round the earth. And it should be remembered that in Canada there are great alternations of temperature, the heat of summer being intense, and the cold of winter extremely bitter.

Iron in India.-There was an interesting series of specimens shown in the Indian department. Iron ores, chiefly earthy-brown hæmatite and magnetic ironsand, occur abundantly in several parts of India, and have been smelted, from time immemorial, by the natives in small furnaces. The East Indian Iron Company sent an instructive collection of Iron Ores and the various products which they yield. There are several blast furnaces in India on the European model, using charcoal as fuel. It is a remarkable fact, that in one locality in the

Nerbudda Valley, good Bar iron, but only in small pieces, can be made and sold by the native smelters under 5l. per ton.

Swedish Boat Plates.-Sweden's chief ore is magnetic oxide, of which fine and characteristic specimens from various localities were exhibited. An instructive series of the far-famed Dannemora ores and the associated rocks specially deserved attention. The ores from this locality are among the finest in the world: and the iron which they yield always commands a high price, on account of its producing good steel. The Swedish iron ores differ much in quality, even when in appearance they closely resemble each other.

One of the remarkable objects shown was the fore part of an iron paddle steamer, 200 feet long and of 120 horse power, which, during a fog in September, 1860, and while going at the rate of eight or nine knots an hour, struck on a rock. The iron was "crumpled up like a piece of brown paper," and yet the vessel got off and proceeded without difficulty to Stockholm, about 100 miles distant. The plates were made and the vessel was built at the Motala Iron Works.

GALVANIZED METALS.-Amongst the exhibitors of Galvanized Metals were Morewood and Co., who say that their materials are more durable than zinc. They may be applied in the form of tiles, which are 3 feet by 2 feet, and are curled at the edges to finish as rolls, and are stiffened by transverse grooves. They are also made in sheets of 500 feet and upward in length: thus they can be laid with great expedition by any laborer who can use a hammer; whilst considering that boarding is not required, the cost, say the patentees, is less than asphalted felt. Amongst the other productions of the same manufacturers, were welded-iron water and gas tubes.

With galvanized corrugated iron Morton and Co. can cover an area of 100 feet square (plates and uprights only, furnished them) in five spans, for £370. They can provide and erect an iron cottage with five rooms and entrance porch for £120.

For Zinc Roofing, the Vieille Montagne Company, and their manufacturing agents, F. Braby & Co., were exhibitors. Zinc is now constantly employed in Paris, for buildings much larger in scale, and more substantial in construction,

than the London houses.

Wolston's Torbay Iron Paints for coating materials which are to be under water, or in a position to be affected by damp, are manufactured at Brixham, Davenport, and are successfully used in dockyards and public works. A caisson in Woolwich Dockyard, painted nine years since, is in a perfectly sound condition, both under water and between wind and water. It is is also said that the Torbay paints have been found to stop corrosion that has set in. Webster and Horsfall exhibited a case of Iron Wires, including music, needles, and flat spring wires, the latter manufactured from the

patent steel wire, which was also shown; with samples of submarine telegraph cables, coal-pit ropes, and ropes for ships' rigging. There were shown two coils of Steel Wire without a weld, of the extraordinary weight of 1 cwt., said to be the heaviest coil ever manufactured. The whole power of a 100-horse engine was required to roll it, and Webster and Horsfall's mill is the only mill in the country at which it could be made. This wire is to be used for pit-guides, in lieu of the ordinary iron guides, liable to frequent breakage at the welds.

Smith and Co. sent from Halifax a bloom, or piece of the best Swedish iron, and specimens of all the stages of manufacture from it down to the smallest sizes of wire. The first stages down to the rod gauging No. 2 or 4, are manufactured while the iron is hot; after that the iron is drawn cold through steel plates similar to the small model exhibited, with some sizes of wire in it; and as the process of drawing hardens the wire, it has to be annealed or softened at various stages, and then drawn again. The above piece of bloom, measuring only 8 inches long and 3 inches square, and weighing 20 lbs., would, if drawn as small as the finest wires exhibited in the same case, measure 110 miles in length. They will give you 1,000 feet of wire out of a brass farthing; 70,000 feet of wire, or a sheet of brass, 12 feet square, that will not exceed one pound in weight.

The Hereford Screen, made by the Skidmore Art Company, at Coventry, for Hereford Cathedral, is probably the finest piece of modern metal work in existence. It has been executed from Mr. Scott's designs since January, 1862; it is much larger in its dimensions than its companion at Lichfield, and, indeed, is the largest piece of architectural metal work ever executed. Iron is of course the principal material used, though in the decorative details copper and brass are largely introduced. In these combinations the fine examples which the early metal workers have transmitted to our time are studied with conscientious care, so as to adhere to the lessons of the past in a work that in itself is perfectly original. Thus, in the Hereford screen we find the iron wrought both into true grilles, and also elaborated after the manner of the early chasers into the richest iron filigree. The brass and copper work has been dealt with in the same spirit, and the capitals supporting the screen are most happily adjusted to the requirements of architectural conventionalism. The copper flowers by which these are enriched have the softness and beauty of nature, though all, after the old style, are worked out with the point of the hammer from sheets of copper. The copper is throughout left of its own natural color, but the brass work is intermixed with broad masses of vitreous mosaic. Where paint is used upon the iron, all the colors employed, with the exception only of the green, have been obtained from oxides of the metal itself; though the coloring and gilding have been applied only with a view to

the effect of the whole piece when shown in the subdued light of a cathedral nave.

The whole composition consists of a double arcade of five primary and ten secondary arches, blended in a single group, though each retains its own individuality. The centre arch, forming the passage, is very lofty, and is enriched with the most exquisite scrolls of flower and foliage. The shafts for the arches are of mixed brass and iron; and, as at Lichfield, the whole is adorned with examples of architectural sculpture, figures of angels, &c. These figures are perfect studies in themselves.

In the Hardware Court were several descriptions of Cooking Apparatus, of which one showed great novelty of arrangement, namely, the patent Duplex Range, by Edward Deane & Co. It has two fires of different sizes, separated and backed by a T boiler. Each fire has a separate oven of proportionate size, flue, and hotplate. In combination with the patent Revolving Roasting Apparatus-as many as nine joints can be roasted at one fire-120 pounds of meat may be roasted; the same quantity baked in the ovens; and the same quantity again stewed on the top of the stove; while the steam boiler at the back will boil 3 cwt. of potatoes, and the circulating boilers will keep 60 gallons of water constantly hot, the whole cost of the fuel per day being one shilling. The roasting apparatus consists of a cylindrical meat-screen, within which three sets of joints, one above the other, revolve first round a general centre, and secondly round their own axis, each joint having a separate dripping-pan.

Brown and Green, of Bishopsgate-street Within, obtained the prize medal for a large Kitchen Range, fourteen feet in length, containing four roasters, or ovens, and three boilers. It is stated that the range is capable of doing all the plain cooking for more than 2,000 persons with a consumption of less than one ounce of coal per head per day, this being one of the results of a practical trial of this range before it was placed in the Exhibition: these results are certified by the inspector of cookery for the army, who conducted the trial by command of the War Office. This large Kitchener also provided for the certain cure of smoky chimneys; the ventilation of the kitchen through the upper part of the range, whereby are prevented oppressive heat in the kitchen, and close smell of cooking; and the facility of roasting meat in front of the fire at the same time that the whole of the apparatus is kept going.

Chandeliers, Gaseliers, and Lamps.—Some of these tasteful works were designed by Mr. Digby Wyatt, and range in price from 50s to 100 guineas. Hinks and Son sent a case of new patent Lamps for the complete combustion of the commonest oils, without glass chimneys: some were glass elaborately gilt, and others of opal and bronze.

Harrow and Son, Portland-place, exhibited an Eight-light Gaselier, cast in brass, construc

ted in form of an ancient grillier, or fire-pot, the upper bar consisting of eight inverted friezes, richly wrought and divided by heads of dragons, from whose mouths issue fire, and lightly-poised gas-jets. At the bottom is a very bold boss, composed of two large salamanders, intertwined in fierce struggle, their feet grasping the lower ring or bar of the suspended firepot, and thus forming its base.

The famous Birmingham Buttons, of gold and steel, and fanciful descriptions, were also tastefully shown. So perfect is the machinery for making buttons, that the manufacture is completely effected by the single revolution of a wheel.

Brass Tubing, some of it nine inches in diameter, a case of Bookbinding, in metallic covers; Brass Hinges, Door-knobs, and Handles, in endless array. The Cornice Poles and Brackets, by which small houses are most economically fitted, were exhibited here, made by the stamping process of Mr. Hill.

Locks and Safes.—Mr. Harley, of Wolverhampton, contributed a case of locks, remarkable for their mechanism and elaborate and artistic finish. Some of the padlocks were as small as the stone of a ring, and others as large as a cheese-plate; and some of the folio locks are also so minute that a dozen of them might be sent by post for two stamps.

Messrs. Bramah maintained their old reputation by exhibiting models and specimens of the well-known locks, as manufactured in their ordinary business. Hamilton and Co., Royal Exchange, showed a lock to be locked without a key, by merely turning a brass knob, but which is opened by a very small key.

Hobbs & Co. showed every part of a lock and key in course of manufacture by their machinery: they also exhibited a series of twentysix locks, varying in size from that suited to the smallest cabinet to a large cupboard, so constructed as to be open with one and the same key. One of their larger locks, the "Protector," by a peculiar arrangement of certain parts behind the bolts and levers, is stated to be unreachable by any lock-picking instrument whatever. When any tampering is attempted on the lock by pressure on the bolt through the key-hole, to discover the opening position of each lever, the bolt-protector comes into action, preventing the pressure affecting the levers in any way.

Chubb and Son showed a splendid and unique collection of Locks and Keys. There were about 300 locks exhibited, varying between a gigantic rim lock weighing more than 2 cwt., and as finely finished as a lady's watch; and an elegant little gold lock, with four tumblers, set in a finger ring, and weighing 16 grains! Some fifty keys were shown with elaborate bows, three so much so, that, although small, they are valued at upwards of a hundred guineas; the bow of each being composed of minute particles of steel, all separately riveted, and resembling so many brilliants.

STEEL MANUFACTURES.-The manufacture of steel and steel articles, on anything like a large scale, is confined to very few countries. In 1851 it was ascertained that while we produced annually about 45,000 tons of steel, Austria, which came next to us, produced only 13,000, and all the states of the Zollverein taken to gether, but 8,000. Perhaps nothing indicates the progress which has been made during the past few years, so clearly as a comparison between the steel found at the Exhibitions of 1851 and 1862.

The so-called homogeneous metal, which has excited much attention of late, is extremely malleable and tough, and may be placed midway between wrought iron and ordinary steel; it may be regarded as steel containing a low percentage of carbon. This is the metal of which Mr. Whitworth has formed so high an opinion. Examples of it were exhibited by Shortridge, Howell, & Co. Pieces of tubing formed of this metal were shown flattened down vertically, which might readily be mistaken for caoutchouc. It is stated to have been produced by melting pieces of Swedish iron and carbonaceous matter.

In the French Department, Jackson, Son, & Co. exhibited steel objects made by the Bessemer process. The Swedes sent both iron and steel made by this process. Bessemer steel was sent from Kloster Works, Dalecarlia.

The process of Uchatius excited some attention a few years ago, especially in London. Samples were exhibited in the Swedish department. This steel, strange to say, finds a ready sale at prices ranging from £50 to £60 per ton, which are higher than can be obtained for Bessemer steel in Sweden. It is said to be especially good for sword blades. It is made by melting Bispberg iron ore, mixed with charcoal, in Belgian crucibles. This ore is remarkable for its purity.

Cast steel, made by melting together wrought iron and charcoal pig iron, was shown in the Swedish department, by Rettig, Geffe. Cast steel, made by melting together wrought iron and refined pig iron, was exhibited by Dr. Price, in the British Department.

In the Austrian Collection were specimens of the so-called wolfram steel, made by melting together cast steel and the mineral wolfram. It breaks with a very fine grain, and is hard and tough.

In the Austrian Department were drawings of Mayr's furnaces for casting steel on Siemens's principle by his "regenerative furnaces. Lignite is the fuel used, of which three parts by weight are required to melt one of cast steel. In six days between five and six tons are melted in one of these furnaces.

Krupp's Cast Steel.-Krupp affects considerable mystery in his processes. His works in Essen are reported to occupy 180 acres of ground. It is stated that he employs puddled steel, which is broken up, assorted, and remelted in crucibles. This variety of steel does

not appear to be adapted for cutlery. He consumes all the spiegeleisen produced by Müsener & Co. It is affirmed that there is a great consumption of plumbago and leather parings at the Essen Works. Each crucible is said to contain 70 lbs. of steel, and the furnaces in which they are heated vary much in dimensions, the smallest holding two and the larger twenty-four crucibles. When a large casting is required, the organization has been carried to such a remarkable degree of perfection that, at a given signal, all the crucibles needed are ready to be taken out of the furnace at the same time. Their contents are poured with the utmost rapidity into a large reservoir, and from this the metal is cast. By this means, as in bronze founding, on the large scale, homogeneity is attained. The apparatus for working the steel is the most gigantic yet constructed. There is a steam hammer weighing 50 tons. The anvil face weighs 185 tons, and cupola furnaces were built expressly to melt this large quantity of metal. The largest casting in the world is the great bell at Moscow, reported to weigh 192 tons; but it cracked in cooling, and was never removed from its birthplace. Krupp's anvil rests on eight blocks of cast-iron, weighing from 125 to 135 tons each, and making a total weight of 1,250 tons of cast iron! This solid structure of iron is supported on a wooden foundation, 40 feet square. The largest casting exhibited by Krupp in 1851 weighed 2 tons, and the largest in the recent exhibition weighed 21 tons. It is in the form of a solid cylinder, about 9 feet high, and 3 feet 8 inches in diameter. It has been broken across to show fracture. The largest casting Krupp ever made weighed 25 tons. Now, when we reflect that this enor mous mass of metal is melted in comparatively small crucibles we get an idea of the perfect organization requisite to have every crucible ready and the pouring effected at almost the same moment of time; and it is in this organization that we are disposed to think one great merit of Krupp consists. Krupp exhibited shafts, rolls, railway tires and wheels, locomotive axles, and guns. There was a good catalogue in German, also a price list of the cast steel guns. A finished gun of eight inches calibre, turned, bored and rifled, without breech closing apparatus, is advertised at £975. Krupp has supplied locomotive axles to some of our largest railway companies, and crank axles of marine engines to some of our most celebrated marine engine makers.

Bessemer's Steel.-Bessemer made an admirable display both of iron and steel produced by this process; with specimens illustrative of the quality of the metal, as shown by hammering, punching, bending, twisting, stamping, rolling, drawing into tube and fine wire, turning, polishing, &c. A rail was shown 84 lbs. to the yard, which may be supplied at £13 per ton.

There were a crank shaft of a 50-horse engine in one piece; piston rods for engines of from 50 to 260 horse power; the powerful screw of

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