imbued with that idea, that after visiting my works at Sheffield, he communicated to the authorities at Woolwich what he had seen; and on more than one occasion I had interviews with him on the subject. Indeed, I went so far as to give a written contract to the late Lord Herbert, who was then at the head of affairs at Woolwich. In that contract I undertook for £5,000 to erect enough machinery on my principle to produce two hundred tons per week of cast steel blocks for the Government, and my estimate was that cast steel blocks poured into their own moulds would cost £7 per ton.* Lord Herbert said he would refer the question to Sir William Armstrong, and I never heard anything more about it. With regard to armour-plates, as far as my opinion goes, Bessemer steel is totally unfitted for the purpose. It is very well to say "there is nothing like leather," but sometimes leather is not good. I believe that in the condition of steel we shall never produce an armour-plate that will stand even cast-iron shot. I believe that an armour-plate requires to be exceedingly soft and tough, and not hard like steel. In fact, the general characteristics of steel wholly unfit it for armour-plates. I believe also that a considerable improvement in armour-plates may be made by in part carrying out my process of steel making; that is, if we reduce cast-iron to the state of very soft pure malleable iron, and do not recarbonise it, we shall then have a metal the toughness of which is almost beyond belief. Indeed, excepting the very best copper, I do not know any metal that is equal to it in toughness, and its softness approaches so near to copper, that it may fairly be taken out of the category of common iron. I believe that that metal may be made into armour-plates with great advantage. But in order to get that excessive toughness which you require in the armour-plates, if you cast a large mass a granular structure will run through it, but if you roll it into thin plates and weld them together, the structure will be much changed, and we shall then have separate layers of toughened metal. If we take a large granular mass of steel and compress it from one foot square to six inches square, we shall find the structure altered very little indeed. But if you bring it into a much smaller space, it appears that the crystals get elongated, and that their cohesion is very much increased. Now I think that that increased strength and toughness can be best got by reducing the metal to small sections; but I think the ordinary mode of welding renders it so exceedingly imperfect that we should try and improve in that direction; and it is in that direction I am attempting to go. Every one who has seen the experiments on armour-plates will have observed that when the shot strikes a plate and penetrates to a certain extent, large masses generally fly off from the back. When these large masses tear off we always get a large portion of the surface separated in the direction of the weld of the plate, but if welding ever took place thoroughly, that separation would never take place.

Admiral HALSTED: It never has been done.

Mr. BESSEMER: It never has been done, and never can be, on the system by which welding is now attempted. The mode by which I think welding may be effected is this. Having rolled a certain number of plates, I would put them in diluted acid in the same way that you prepare plates for tinning, or galvanising, by which means the thick coat of oxide which they acquire in rolling is separated from the metal. We have then a clean surface of metal to act upon. When they are taken out of this pickle-bath, I would put upon them a sort of wash, that is, any easy melting flux, silica being one of the constituents. If you then put a number of plates so coated together, and get up a welding heat upon them, a good weld may be made, for there is no oxidised surface to begin with, and the surface is so coated and protected from the contact of atmospheric air that they acquire no new coat of oxide while being heated up. Again, we have between all these surfaces (by the time the welding heat is arrived at) a perfectly fluid matter, which under the pressure of the rolls will come out from between these surfaces; and as in the act of soldering, you allow metal to come in contact with metal, and a much more perfect union takes place than is possible when there is a hard dry scale of oxide between the surfaces of the several plates. How far this may produce an absolute junction of the metals

*This was in 1859, when the pig iron employed was nearly £2 per ton cheaper than at present.-H.B.

it is difficult to say; but I think it will produce it much more effectually than at present.

The CHAIRMAN: Just on the same principle that borax is used for soldering.
Mr. BESSEMER: Exactly.

Mr. BARRASS: Is it possible to cast a gun with a core?

Mr. BESSEMER: As far as my experience goes the casting of steel with a core is an exceedingly difficult matter. There are very few materials known to us that will stand the excessive heat of melted steel without going into a state of fusion Ordinary sand fuses rapidly in the presence of steel in a melted state; and whenever the core commences to fuse on its surface, the gases generated can never pass out through the pores of the mould, but they pass into the metal, which becomes imperfect. Captain SCOTT, R.N.: Will you allow me to ask what is the size of the guns that the Prussians have ordered?

Mr. BESSEMER: I am not at all aware.

Mr. D. LONGSDON: Perhaps I may be allowed to supply that information, being the brother of Mr. Krupp's agent in this country. The guns ordered of Mr. Krupp

by the Prussian Goverment have been 7, 9, and 11 inch.

A MEMBER: Will the gentleman allow me to ask whether they are cast solid, or hollow?

Mr. LONGSDON: Solid, afterwards hammered, and then bored.

A MEMBER: We hear that the Americans cast guns of heavy calibre with a core, and in order to avoid what Mr. Bessemer mentioned, the melting of the core, they have an ingenious plan of allowing water to percolate through to keep it in a cool state. If that can be done, I wish to ask Mr. Bessemer whether he thinks it would be desirable?

Mr. BESSEMER: I think that the amount of forging which is necessary on a piece of cast-steel to develope its full strength is such, that it would be impossible in a gun cast with a core, to give it the amount of working that is necessary to develope its proper strength. The forging of a hollow gun would be very unsatisfactory in the interior; we could not introduce the mandril into it; for, if it closed upon it, the mandril could not be got out again.

Captain SCOTT: I can supply some information that may complete this paper. You have mentioned about steel for guns. There are steel guns in the Arsenal which were supplied by Krupp. There is a 110-pounder, a 40-pounder, a 25-pounder of his, and there is also a gun supplied by Naylor Vickers. The whole of these guns went through the one hundred rounds with increasing cylinders, and were found to be perfect afterwards, with not a single crack to be seen in them. The 25-pounder of Krupp, and the 25-pounder of Vickers were then fired with double charges. They are still uninjured, and may be seen by anybody who wishes to look at them. No other guns have ever stood such a proof before. All the coil guns that have been similarly tested have been more or less injured.

Admiral HALSTED: To what size have you yet produced your ingots?

Mr. BESSEMER: At our own works we have only produced ingots up to six tons in weight.

Admiral HALSTED: What diameter would that be?

Mr. BESSEMER: That would make one of our largest ship guns, I suppose, about five tons when finished. We are making apparatus, however, for one firm that will produce masses twenty tons in weight: indeed we should have no difficulty in producing fifty tons.

Mr. ASTON: Will they put down steam hammers in proportion?

Mr. BESSEMER: Certainly.

Mr. ASTON: I believe Mr. Krupp is using steam hammers of one hundred tons.

Mr. BESSEMER: He is using very large ones; I do not know the weight.

Mr. ASTON: He has had several of fifty tons.

Mr. LONGSDON: The largest steam hammer that Mr. Krupp is using is fifty tons, with a fall of 10 feet. He is now putting down to assist that hammer, which has so much to do in consequence of recent orders, two hammers of thirty tons each.

LECTURE.

Friday, May 13th, 1864.

GENERAL H.R.H. THE PRINCE OF WALES, K.G., K.S.I., &c., &c., Vice-Patron of the Institution, in the Chair.

RAILWAYS STRATEGICALLY CONSIDERED.

By Captain H. W. TYLER, R.E., Railway Department, Board of Trade.

AN eminent soldier and author of the last century-Marshal Saxeasserted that legs were of more value than arms in war. Other writers express the same idea in saying that the whole secret of war consists in marching; and the Archduke Charles proves the truth of it by showing that certain battles are won by successful strategy before they are fought. Now strategy is simply the art of moving military forces to the best advantage on a theatre of war; and the objects to be attained in the practice of it during a campaign (as well as in the practice of tactics during a battle) are (1) to be superior at the proper time and at the decisive point, and (2) to threaten the communications of an enemy without exposing your own. Setting political considerations aside, war is from beginning to end a question of communications. The Romans, when they subjugated a country, set to work at once to make roads through it, and those roads remain to the present day. In now forming the plan of a campaign, the main points to be considered are the direction in which and the lines by which the forces shall be moved. In carrying it out, the principal care of a commander is to prepare for victory by employing the means of communication or transport at his disposal to the best advantage, and massing his forces on the decisive points. The position of those so-called decisive points depends upon the communications of the country. The nature of ground, the position of rivers, mountains, marshes, is chiefly important as affecting the progress of the troops, and the way in which their communications can be secured. The manoeuvring which sometimes precedes an engagement is effected with a view, either to cut off a portion of the enemy before the remainder can come up, or to obtain a position from which his communications may be threatened; and a mere threat of this sort is frequently sufficient to force an enemy to retreat without fighting. During a battle, on a scale of whatever magnitude, the victor looks mainly to the communications of his enemy, the vanquished to his own. And in the course of a pursuit, the object of the victor is still to intercept his

foe's communications, and thus to cut him off from his base of operations.

Communications being thus, as it were, of supreme importance in warfare, and the success of campaigns depending mainly upon their being used to the greatest advantage, it is a matter of the highest interest to all military students to study the effect of railways upon the various operations of war, and to profit, as far as possible, by the experience which has been afforded in other countries on the subject.

It is not yet forty years since passenger railways came into use, and there were at the end of last year 12,299 miles of railway open for traffic in this country alone,-in which 400 miles a-year are still being constructed. In round numbers there are about 113,600 miles of railway in the world, of which 53,000 are in Europe, 52,000 are in North America, 6,000 (principally in British India) are in Asia, 1,800 are in South America, 600 are in Africa, and 200 are in Australia. They will no doubt continue to increase for a length of time with great rapidity; and the more they spread over a country, the more important they become in a military sense. The tendency of railways in every country is to radiate from certain centres of traffic and commerce. The trunk lines are first filled in, then secondary lines and cross lines, and, finally, the means of communication between, first, the principal, and, secondly, the inferior places become multiplied. It is impossible now to lay out any long line of railway in this country which does not compete more or less with existing lines. The junctions at which some of these lines meet must become strategic points of the greatest importance to the defence of every country-points on which an invader would at once seize, and the loss of which would very much hamper the operations of the defenders. Looking at the map of England, such points are at once apparent. An enemy landing on the south coast would naturally regard the junctions at Brighton and Lewes, of the line from London with the South Coast Railway, as points of primary importance, and Canterbury, Ashford, and Hastings on the one side of it, as well as Havant (on the north of Portsmouth) and Bishopstoke (on the north of Southampton) on the other, are also places of great importance for the same reason, namely, that the main lines out of London join the coast lines at those points.

Of these junctions, Canterbury and Ashford derive protection from the fortified position of Dover, and Havant and Bishopstoke from that of Portsmouth; and it is evidently not necessary, under existing circumstances, to throw up works in anticipation for the defence of the remainder, as it might be if our coasts were more accessible, our fleets less strong, and our volunteers less efficient. But with our vital points placed, as they are (except Spithead, the most important of them all), in a respectable position of defence, and with 150,000 gallant volunteers ready to assist the regular forces in manning our forts, as well as in more active operations, we need be under no apprehension for the safety of the country. I would, however, while on this subject, say a few words in regard to the defence of our coasts. There is a very general opinion-and confirmation has been prominently given to it by a gallant naval officer in this theatre-that our

system of coast railways might, if the connection were completed at certain points, be relied upon for conveying troops to prevent the landing of any hostile force. I need hardly say that any invasion of this country would be attempted in great force, and that the portion of the coast which would require to be specially guarded lies between Portsmouth and the Thames. The enemy might be expected in several divisions, and at different points, and our great object would be to have four or five thousand men (including a strong force of artillery) on the spot, ready to fire into their boats as they approached the shore, supported by the fire of their larger vessels. If they were to land unopposed, or inadequately opposed, then we should have lost the best opportunity for attacking them at the most critical period of their first operation,-as they were approaching the shore, leaving the boats, and forming on the beach. Now the coast railway cannot follow all the sinuosities of the coast, and is in places several miles from it; and during the time that would be occupied by a body of troops in marching (on being warned by telegraph) to the railway, in embarking upon it in successive trains, in performing their railway journey, in disembarking from the trains, and in marching to the spot at which a feint had been made, or at which their presence was really required, these operations having taken all the longer for want, perhaps, of platform and siding accommodation at the particular points of the railway employed, the enemy would have reached the shore, and would have taken up a position in force to cover the landing of more troops.

In this, as in all other cases, railways are comparatively of little use for short distances, or where troops have to march any great distances to and from them. The length of time occupied in preparing the trains and embarking the troops (including cavalry and artillery) is considerable as compared with that consumed on the journey. On the other hand, 20 or 30 extra miles in a railway journey, when the troops are once embarked, is only a question of an hour's travelling. It is obviously in the case of long journeys, in which the troops can perform in an hour, and without fatigue, what would otherwise be a hard day's march, that they are of most service.

If we were obliged to make serious preparations against an invasion, we should do well, for these reasons, not to rely upon coast railways alone, but to form camps in the necessary localities round the coast, and to organize movable brigades, able to move independently of the railways, or to take advantage of them, as might be required.

In considering the relative importance of roads, rivers, and railways, we must reduce them to the common measure of time. In military operations, victory is a question of days, or hours, or sometimes even of minutes, in the movement of troops, when the forces are on anything like an equality. The time that will be required to march a certain number of troops to a given spot having been calculated, and their support being a matter of vital importance to the contemplated

Such, for instance, as that which was so efficiently equipped and instructed at Shorncliffe in 1804, under (Sir John) Moore, and which afterwards became so celebrated as part of the Light Division in the Peninsula War.