being so great that five patents for three years, at 30l. each, are required instead of one at 100l. for fourteen years; the five patents, if extended to fourteen years, costing about 160l. each, or 800l. instead of 350l., if English, Scotch, and Irish be included in both cases. Many of these latter patents probably did not go beyond “protection,” being, in truth, taken to prevent others from obtaining patents for every variety of article that could be made out of the improved iron and steel to the detriment of the real inventor.
Thus he went on, ever working through good report and ill report, falling often from a height where success seemed attained, not from false calculations, but from some adverse and before undiscovered fact in nature, most valuable to us to know, but not tending at the time to replenish the inventor’s purse.
At the British Association of 1857, Mr. Bessemer read a paper, wherein he described his process of iron making. The ordinary process is first, to run it from the ore into pigs by one heat. Secondly, to re-heat it and “puddle” it, i.e., stir it about in a melted condition with iron rods moved by men’s arms till it becomes stringy and tough, and gets rid of some extraneous matter. Thirdly, to beat it by hammer into a mass, called technically a bloom. Fourthly, to roll this bloom into a bar or bars, making the commonest iron. Fifthly, to cut the bar into short lengths, and pile them up. Sixthly, to reheat this pile and forge it into another bloom; and, seventhly, to re-roll it into a bar or bars. If, during the process of heating, the oxygen of the atmosphere gets access to the surfaces, scale is formed, which prevents perfect adhesion under the hammer, and the metal is not homogeneous.
Mr. Bessemer simplifies all this. When the metal is melted in the great furnace it is run out into a huge clay crucible, practically a colander, by reason of several openings in the bottom, through which the metal would run were it not impeded by a strong blast of air under great pressure, which is forced through all the interstices of the iron, and instead of cooling it, raises the heat to a greatly increased intensity. This burns away the carbon, which constitutes the chief difference between cast iron and malleable iron, and also some other matters; and when the metal is poured out, it is pure iron, if the process be carried on long enough, or if stopped at an earlier period so as to leave some carbon in it, it is pure steel: in both cases malleable. Thus one heat serves to make a malleable ingot, which is only limited in size by the size of the crucible, which may contain two tons; and, as many crucibles may be used and poured out together, there is no reason why a homogeneous lump of fifty or more tons should not be produced, either of iron or steel, which may be dealt with by the hammer, or by rolls, or both.
In rolling thin sheets of metal in the ordinary manner, the size is limited by the difficulty of retaining the heat. By another arrangement of Mr. Bessemer, this difficulty may be obviated. Hollow rolls are used, through which a stream of water pours, and on the surfaces of which jets of water play. Between these rolls, which are placed horizontally, and form a tank or channel when they approach each other, the molten metal is poured, and thus a sheet of any desired width or thickness may be formed, and only limited in length by the supply which the crucibles are capable of keeping up. The ore goes into the furnace a crude stone, and comes out of the rolls a sheet of tough metal. Iron-making is thus rendered as simple as the paper-making processes, where the rags go in at one end of the train of apparatus, and come out at the other perfect paper.
At Baxter House, St. Pancras, this new process of melting was first exhibited to the public, and excited an equal amount of wonder and incredulity. On one occasion, a sort of Welsh St. Thomas, iron-doubting, sneered as he saw the metal poured, and asked: “Do you call that malleable iron?” The inventor went into a shed, brought out a carpenter’s axe while the metal was still red, and cut three notches in the angle, just as might be done at the angle of a square foot of timber. The silent answer struck St. Thomas dumb.
Still the inventor had much to learn. The iron hissing, boiling, and bubbling in its clay colander, was poured out in its ebullient state, frothing like so much Champagne; and as it cooled was filled with innumerable air-cells; and the apparent want of success filled the mouths of fools and scoffers with matter for exultation. Far and wide the whole affair was considered a failure; natheless that men of logical mind knew to the contrary. But the resolute inventor stuck to his work, he had sounded the depth of his invention, but he had not explored many of its ramifications. Two years beheld him again before the world with the verification of his theories and of his earlier practice: the causes of failure unfolded. His next paper was read at the Institution of Civil Engineers; and those who know the critical acumen of that strong-brained body of men, and were present at the reception of Mr. Bessemer, and beheld the enthusiasm spontaneously kindled, as important truths were enunciated, and sample after sample was exhibited, opening new capabilities to these Anti-Chinese sons of eternal progress, are not likely to forget it. No actor at a successful début, no writer of a successful play, was ever more warmly greeted. A small cannon, a railway axle, a three-ply cable, twisted up of cold iron one-and-a-half inch diameter, steel bars and rods of all shapes, a large circular saw, boiler plates of perfect surface and great width, and, lastly, ribbons of iron as thin as paper, were exhibited. A small cylinder was shown of cast metal in a perfect condition, and another cylinder was also shown which had been doubled up flat under the hammer, without exhibiting the smallest crack at the sharp bends, but the tensile strength was shown to be nearly twenty-four per cent. greater than that of the most costly iron made in England.
A sheet of thin iron, reticulated and pierced with holes, almost like a lady’s veil, was produced, and stated to be a skin left on one of the crucibles after pouring out the metal. “Is that