NO. III.

On the subject of the manufacture of armour plates as practised at the works of Messrs. John Brown & Co., Sheffield, we may refer to the following extract from the letter of The Times' Correspondent.

THE visitors were then conducted through the extensive new and old mills and workshops, where some 3,000 hands were busily engaged in melting, bending, hammering, and twisting great masses of seething iron into every conceivable form its stubborn nature could be made to take. It was really a wonderful sight. On every side, amid thick smoke and deafening clamour, the blazing rites of Moloch-the furnace god of old-were being celebrated. Great furnaces blaring in the fierce white glare which shone from their crevices were stuffed to the mouth with monstrous cranks and shafts and uncouth bosses of redhot metal. Every now and then some one of them was opened, with a flash that filled the smoky atmosphere with a glare as from snow, and a mass of metal, seething and spluttering in a blaze of sparks, was dragged off and moulded, like so much wax, under the blows of steamhammers that made the earth tremble and the whole building to jump and chatter under the stroke, as if from the shock of a little earthquake. It was wonderful to see the skill with which the groups of workmen, uniting all their individual exertions in a series of violent efforts like a weird species of dance, contrived to hedge and move about the great masses on the anvils, so that the hammer struck only where and how they chose. While the heat lasted in the mass, and that was for a long time, they never paused or slackened in their work, and though literally almost scorched by their proximity to red heaps, they kept on toiling till the work was done; and the lump that a quarter of an hour before was almost melted iron was picked up by some huge crane that came travelling along the smoky walls, and carried off, glowing through the gloom, a finished piece of work. At other places there were tilt and lever hammers wearying the very air with the clattering din of their tremendous strokes. At others, great ingots of steel were cast by the Bessemer process-small plates were rolled and roughly cast aside in great red slabs to cool, or hurried backwards and forwards in iron trucks, scorching even the hardened workmen out of their tracks as they came burning past. On every side there were furnaces and smoke and red-hot metals, while in out-of-the-way nooks men in steel caps and wire vizors, and cased below in rough steel leggings, like jack boots of iron, fought in a cloud like so many salamanders round some rough

mass that was dangerous in its fierce heat, and which sent back aggressive spurts of red-hot metal in return for every blow. Such fiery combats as these were going on in all directions; the 'Sheffield carpet of the factory-iron plates-was hot and painful to the feet; the air was arid with a sulphury warmth that was like the glow of an overheated stove. When we have said thus much, and added that there were roaring pipes of steam mounting into the air, side by side with great iron trumpet-shaped piles of chimneys, out of which jets of red flame roared and flapped into the smoke above like gigantic flambeaux—that lower down long lines of lathe-bands flew noiselessly in all directions, and that the background was filled in with glimpses of ponderous fly-wheels whirling their arms through the smoke and turning rolling-mills or lapping-hammers, or shearing down with noiseless might the great lumps of iron that were brought in to be cut up,— we have said enough to indicate the view which met visitors on their first introduction to this glowing scene of industry. Though not the first, yet by far the most important process which their Lordships were shown, was the operation of rolling the great plate-by far the largest single plate that has ever yet been rolled in the world. This took place in what are called the New Mills of the Atlas Works, which were used on Thursday for the first time, and where great ranges of furnaces have been erected, with their mouths opening on the iron tramway which leads direct to the double rollers through which the plate passes. One may guess at the solidity required for mills of this kind when it is stated that some of the rolls used at this mill on Thursday have a first foundation of no less than 60 tons of solid iron, resting on masonry carried far below the earth. The rolls themselves are 32 in. in diameter and 8 ft. wide, and are turned by an engine of 400 horsepower, putting in motion a fly-wheel large enough, apparently, to make a world rotate if only well balanced on its axis. A powerful screw, applying its force through compound levers, allows the distance between the rollers to be adjusted to the fraction of an inch, so that the plate which on its first rolling is forced through an interval of— for instance, 12 inches apart-is on its next wound through one of 10, next through one of 8, and so on till the required thickness has been carefully and equally attained by tremendous compression through every part of the metal. There were a great many visitors to see the rolling of this formidable mass, which was fortunate, as one would certainly be frightened to witness the terrible process alone. After some delay and quick glimpses made by the most hardened workmen, who, rushing up to the door of the furnace, got a half-blinded glance into its white interior, it was decided that the mass was ready; for,

strange as it may seem, an armour-plate requires more than mere heating, and has to be cooked and watched in its cooking with as much care as if it were an omelette, and the plate that is drawn before it is 'done to a turn' generally remains a permanent ornament of the unlucky manufacturer's workshop, which no one will have at any price. When at last this eventful moment had arrived, on Thursday, the door of the furnace was slowly raised, and a colossal pair of pincers with very long handles, fastened to a chain drawn by machinery, was swung in. For an instant some men rushed forward, and, shielding their faces from the deadly heat that shot from the furnace, adjusted the bite of these forceps on the plate, and then ran back as the chain began to tauten, and the great inmate of the blazing den was slowly dragged forth on to the long iron trucks in front of the door, and there lay in its huge length and thickness a mass of living fire, which none could approach, or scarcely even look at, so fierce was its glow and terrific heat. The chains that should have pulled it forthwith to the rollers were too slack; and then arose shouts and cries and commands, as the men did battle with this mass of fire, coming so near it, in their attempts to gather up the slackened chains, that one literally almost expected to see them fall, scorched and shrivelled, on the ground. In its great glare they fought and struggled with the chains till at last all was adjusted, and the great pile of angry fire began to move slowly downwards towards the mills, the men following it with hoarse shouts and directions, now hid in steam, as buckets of water were dashed over the mass, and the next moment standing in an atmosphere of white light, to which the light of the day around was mere dusk. The rollers did not bite directly the mass came to them; and when they did, the engine was almost brought to a standstill by the tremendous strain upon it: but at last the soft plate yielded, and the rollers seemed to swallow it as they wound it slowly in, squeezing out jets of melted iron like squirts of fire, that shot about dangerously as the pile was compressed from 19 inches to 17 inches thick by the irresistible force of the rollers. Ce n'est que le premier pas qui coûte, and the victory was certain when the mass had once passed through the mill, and both visitors and workmen gave a tremendous cheer at the success. From this time it was kept rolling backwards and forwards, the workmen sweeping from its face the scales of oxide that gathered fast upon it with long-handled besoms that, though soaked in water, caught fire and blazed up as fast as they were used. With every time it was passed through, the rollers were screwed closer and closer together, as we have already mentioned, till at the end of about a quarter of an hour, after leaving the furnace an almost melted mass, it was passed through for

the last time, and came out opposite the furnace-door it had so lately left, no longer shooting forth spiteful sparks, but shorn of half its heat, subdued and moulded to its proper form-a finished armour-plate, weighing 20 tons, 19 ft. long, nearly 4 ft. wide, and exactly 12 in. thick throughout from end to end. This is the most signal triumph that any rolling-mills have yet achieved.

Other smaller plates were then rolled with a quickness and certainty that proved the skill already gained in this new and most important branch of manufacture. One plate was 17 feet long by 4 feet broad and 5 inches thick; one, 19 feet long by 4 feet wide and 4 inches thick; one we have already alluded to, 41 feet long by 3 feet 10 inches broad and 4 inches thick. A lesser plate was also rolled 18 feet long, 5 feet wide, with a thickness of 6 inches on one edge and 3 inches on the other.

The method of converting cast iron by the Bessemer process into the tough soft Bessemer metal, a combination of the qualities between soft steel and tough wrought iron, was next shown. It is needless now to enter on a description of the very beautiful and very terrible process, to witness, which the metal goes through in the converter as it is stimulated to a white heat by the passage of the air blown by force-pumps upwards through the mass. No fireworks can surpass the brilliancy of the display this process affords as it approaches its completion, and the stream of violet flame and clouds of burning sparks pour from the mouth of the converter as from a gigantic squib. Nor is it necessary here to enter into a detail of the now well-known process, which was a subject of such controversy a few years since, but which is now being so generally and advantageously adopted throughout England and the Continent. Suffice it to say, that in twenty minutes from the time of putting in the charge of cast iron, it was, without any expenditure of labour, poured out into the mould, an ingot of soft tough steel weighing three tons. This metal, after undergoing hammering, is now most extensively used for steel rails at stations, points, and junctions, where the wear is great, and in these trying situations it seems almost indestructible. A great deal has also been used in making Blakeley rifled guns in this country for both Federals and Confederates. These are the ordnance which the Americans always speak of as Parrott guns, and by them they are more highly prized than those of either Armstrong or Whitworth. Yet it is stated that the Ordnance Select Committee have refused even to try these guns at Shoeburyness. After these processes were over, and the various planing and filing shops had been duly examined, the visitors were entertained by Mr. Brown at a most sumptuous déjeuné.