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inferior purposes can manufacture it as easily and almost as cheaply as merchant iron. Mr. Bessemer's stall is in the highest degree interesting. His process is new. Its value, and perhaps its capabilities, are not yet fully ascertained; but if the produce of his cupola is uniform in quality, there is no doubt it will force its way into general use. The steel ribs, tyres, and axles are excellent, and so are the 'homogeneous' plates, called (not very accurately) to denote that they are not formed of plates welded together. There are many new articles in steel, such as the steel wheels for heavy rolling mills, and steel rolls, which well deserve the iron-master's attention as being more efficient, and in the end more economical, than the machinery now in use. The frequent accidents which have been occasioned by the double-throw crank axles of the locomotive engines suggest forcibly the propriety of substituting for the old
faggotted' axles others of malleable steel. We earnestly recommend this subject to the consideration of engineers and railway boards.*
It would be foreign to our purpose, nor have we space, to dwell on the extraordinary variety, ingenuity, and beauty of the machinery exhibited; yet we must note how forcibly the perfection of the work proves the excellence of the material employed. But how is this triumphant catalogue to be reconciled with our complaints of deterioration and decay? Alas, it is but Regent Street masking the Seven Dials. The Exhibition shows what the iron manufacture is in its sound and healthy parts, what it might be and would be everywhere but for those vitiating influences that infect all the works of man. It would indeed have been more instructive to the public and to the consumers of iron, if each district had sent specimens of its ordinary make, accompanied by lists of their present prices. We should have liked to see side by side the rails and bars of the Welsh district, the rails, tyres, and angle-bars of the North ; the merchant iron, the sheets, the boiler-plates, and the boat-plates of the Midland district. It would be most desirable that ship-owners should be able to compare the difference in quality between boiler-plates at 91. 10s.
* If this is not done, it would be better to employ exclusively the ostrich cylinder engines. On the 24th of June last, when the Great Western Railway express was proceeding at full speed between Banbury and Oxford, the great driving wheel of the locomotive engine, carrying with it the end of the crank axle, detached itself from the engine, sprung from the line, and lodged itself in a pool below. The fracture showed that the pile had never been properly welded. Providentially no injury nor inconvenience beyond that of delay was occasioned to the passengers by the accident.
and boat-plates at 81. 58. Railway directors would learn why rails laminate and crush, and the members of Government boards would see the difference between tough and brittle iron. It would be well worth the while of the Government to make such an exhibition for their own use, in some one of the many docks or arsenals to which there is easiest access. Small specimen purchases made from time to time of pig iron, puddled, and manufactured iron would give most desirable facilities for comparing the products of different districts, and measuring the general progress of the manufacture. To estimate the value of such a collection for the future we have only to consider how precious to us now would be such an illustrated history of the iron trade for the last half century.
There is one point in the Exhibition which strikes very forcibly all who are practically acquainted with the iron trade. In every stall where the materials are exhibited, the same high class tenacious iron is displayed, as if every manufacturer employed the same quality; yet, in many cases, this is not the material of the district to which the contributor belongs, nor is it the material which he is known to employ in his ordinary operations. This tempts us to qualify our assent to the assertion we so often hear repeated, that the traditions of the old iron trade are really forgotten. It would seem they are not so much forgotten as neglected. The merit of tough iron is still as much acknowledged as that of virtue, and with as little practical result. But it is plain that every one wishes to take credit for it; and to this we beg to draw the reader's attention. There is only one weak point in our iron manufacture.
The constant tendency to sacrifice quality to quantity is a disadvantage which it shares with every other manufacture exposed to the high-pressure system of competition. Its peculiar difficulty is, that the supply of the best materials, or of the materials best suited to certain purposes, is limited, and in fact is deficient. It is to supply this deficiency that the attention of scientific men, of manufacturers, and the Government should be directed. All writers on the subject admit that much remains to be done by a more cordial concert between practice and science. There are plenomena which the manufacturer has verified, but which science has not yet explained. There are many important discoveries of science which the manufacturer has not yet turned to profit. The chemical analysis of iron has been carried on to an extent which had never before been attempted, and much progress has been made in correcting the defect of various kinds of iron, by eliminating the chemical ingredients that injure the quality of the metal. Many new and ingenious devices have been invented for improving or abridging the ulterior processes of the manufacture. But many an ingenious project that promises well for future progress is of little present use. It cannot yet be made 'to pay, and for our immediate urgent need there is a simpler remedy. It is only necessary that each district possessed of good materials should make the best quality those materials allow; and to effect this reform nothing more is needed than that there should be a clearly defined demand for good iron sufficiently extensive and sufficiently long continued.
Hitherto it has been a matter of very doubtful discussion whether it would be possible for the Government Boards to acquire the knowledge, or to procure the quality of iron that they will require, unless, to a certain extent, they become manufacturers. But since this point was first mooted, a material change has taken place in the circumstances of the case. At first the demand for iron or iron-coated ships was comparatively small But now it is clear that sooner or later, whether the Admiralty have professedly admitted the necessity or not, the whole navy will be armed with iron. In such a case it is easy to prophesy, that by the force of circumstances, Government will be compelled to turn manufacturer; and it would do well to prepare itself gradually for the position which it must ultimately occupy. Without the aid of the vast means now in their own hands, the Government departments will be unable to obtain the prodigious supplies of ship-building materials they will require; and if the magnificent dockyards and arsenals which have been the growth of centuries are not accommodated to the new requirements of the navy, they will be left without any adequate use. The same reasons which necessitated the creation and the extension of these gigantic establishments, will enforce on us their continuance, whatever may be the material which the advance of civilisation prescribes for ships. Whenever an English king built for himself his first ship of war, he had to encounter difficulties which in proportion were not less than those which beset the naval department now. With much exertion the Admiralty have gained the complete command of their own manufacture when the material was wood : there is no reason why they should not acquire the same mastery over iron. The difficulty of turning sailing vessels into steam boats, which has been successfully encountered, is not much less than that of substituting iron sides for wooden walls. Much, no doubt, may, and ought to be done in private yards; much of the iron work required must be supplied by private firms. Nay, more, all that can be well done ought to be done in this way. But that all is insufficient, and the Government must bring its own vast resources to co-operate. To repair, to refit, to maintain, must always fall to the share of the Government, and how is it to fulfil this task unless it also possess
the power to construct? In the event of a naval action being fought within reach of our shores,-a conflict which must be extremely damaging to both the fleets engaged in it, the future command of the Channel would belong to that Power which has the means of refitting and repairing iron ships with the greatest promptitude: and it must never be forgotten that in their preparations for docking large vessels the French are still ahead of us. Some administrative changes, no doubt, may be necessary ; but in some way or other, the Government must secure to itself the supreme control over the great machinery of national defence and of English greatness. The navy of England cannot be left to the accidents of trade and the frauds of manufacture. Whatever present difficulties may be (and they are many and great), there can be no question what must be the ultimate result. The American Government has officially given it out, as the result of its own experience, that it cannot remain dependent on the private dockyards. It is about to employ the vast resources of an unlimited credit in establishing manufactures for the supply of everything that can be needed for the construction of an iron navy; and the saving which will be thus effected, it estimates not by thousands, but by millions.
It is an important consideration how far the iron that can be brought against us by rival or hostile States surpasses in quality that with which we can oppose it, and we often bear it vaguely hinted that foreign iron, and especially French iron, is superior to the British. Undoubtedly very beautiful specimens from France, Germany, and Belgium, both of ores and of manufactured iron, are to be seen in the Exhibition; and there is an article in the Swedish department to which we would especially call the attention of the naval architect. It is the forepart of a paddle steamer, built at the Motala Works, of 200 feet in length, which struck on a rock when going at the rate of eight or nine knots an hour. The plates are bent into shapes from which a landsman would in vain try to guess their original form and purpose, but they are without a fracture, and the ship arrived in safety at Stockholm. There is nothing but the difficulty of obtaining the price for it, and in the first instance of inspiring faith in his power to produce it, that prevents the English manufacturer from exhibiting an equal quality of iron. But it must not be
supposed that this iron, excellent as it is, is of the kind best fitted to resist shot at high velocities. The famous • Bowling'iron, which approaches it nearest in quality, is not, in our opinion, the fit material for an armour-plate. It is not,
says Mr. Fairbairn, the iron which opposes the greatest resistance to a tensile strain, or to compression, that is most re
effective to resist impact. The presence of a small percentage of carbon causes brittleness; and toughness, combined with * tenacity, are the qualities required.' For this resistance the fibrous English iron may defy competition. In the quantity of production Great Britain is without a rival. Ten years ago it was calculated that the annual make of the country, then about 3,000,000 tons, equalled that of all the rest of the world put together; and now there is no doubt that it might be raised to exceed the aggregate make of the world by half as much again.
If we are beaten by foreign countries, it will be by our own weapons. English managers have found employment abroad, and have carried with them the secrets of the English manufacture. England exports iron in large quantities to foreign countries; and if their armour-plates are superior to ours, it will be because our own War Departments have been less dexterous than their rivals in securing to themselves the best produce of the English manufacture. That foreign iron is not superior to ours, and that, above all, no sufficient quantity of it is to be procured, is proved by the orders which are arriving from all parts for armour-plates. But fortunately the few machines for rolling and hammering plates which at present exist are engaged in the service of our own Government.
The whole of the disposable amount of iron best suited to the purposes of defence is all too little for the present scale of our operations. By the investigations of the Iron-plate Commission, the Government have acquired the knowledge, and obtained the sanction, to enable them to act with decision. The Report of the Commission is, for reasons which are no doubt sufficient, to be kept private. But the main fact which establishes the quality of iron best fitted to resist impact, Mr. Fairbairn has communicated in his interesting lecture, and it comprises all that the public in general are interested in knowing. In the hopeful anticipation with which he concludes we fully
I have every confidence,' he says, 'that the skill and energy of this country will keep us in advance of all competitors, and that a few more years will exhibit to the world the iron navy of England, as of old with its wooden walls, unconquerable upon every sea.'