length of saying, it does involve so large a vessel, and so much strength of structure, to enable that ship to be practically useful, that I really believe you are shut out from the possibility of any other hull to build on than an iron hull. Now, the "Warrior," and vessels of the "Warrior " class, combine in a great degree the requisites which I have laid down as the necessary qualities to start with. The "Warrior," I believe, will be a faster vessel than any vessel whatever in our own navy, or in any other navy in the world. But, then, the "Warrior" does not possess the second requisite, that of being entirely protected from end to end; it is only protected in the centre. But the question of the protection of a vessel is after all what I may term a ship-builder's question. It is not a question connected with the gentlemen of the navy, except in one respect, that is to say, they would all of them be disposed gladly to accept it if the thing could be done, but they imagine probably that the thing cannot be done. Now I believe the thing can be done. I have no doubt in my own mind that a vessel of the size of the "Warrior may be successfully covered from end to end with an armour as perfect as that which she has on, nay more perfect, and yet draw no more water, or rather less than she does at present-in other words, be no heavier, for it is a mere question of weight. With reference to those reports which Captain Halsted has brought forward, of the firing on the two targets, one of a simple plate, and the other of a th plate, backed with a great quantity of wood, though they they really are not very useful for present purposes in the present day, contrary to the conclusion which Captain Sullivan came to, they seem to me to convey the same result. In both cases they appear to have thrown a large quantity of splinters, and to have made holes in the side of the plating nearly identical.

CAPTAIN HALSTED.-I was comparing those with the wooden ships, not comparing them with each other.

:

MR. SAMUDA.—I am comparing them with each other-the two sides, different portions of the same ship. It appeared to me there was a very slight difference in them. The experiments I have made myself corroborate this view. I have fired at iron plates, and then at plates with wood at the back of them, and I can find no difference in the size of the hole, nor do I find the slightest difference in the fracture made by the bullet, whether the wood is behind the iron plate or not. And, if you reason upon the thing, I think you will find it is reasonable to come to the conclusion that there should not be a difference. Now what is the meaning of " backing? Backing means support. If you take an iron plate and put behind it something, the object of which shall be, if this plate gives when it is pressed with a great amount of force, to enable it to resist the pressure, it follows that that which is behind it will come to its assistance. Now, if I put two iron plates accurately planed one against the other, it is perfectly clear that the particles of the back plate would be in as close contact with each other as the particles of the front plate, so that the particles of the front plate, being pressed against the particles of the back plate would receive some assistance from them; and the assistance would probably be this if the front plate were 2 inches thick, and could give a resistance, without the back plate, equal to a force which we will represent by 4-the square of the thickness -the back plate would come to its assistance with another power of 4, and the two together would give resistance equal to 8; but, if I take away this back plate and put on at the back of the front plate a substance which would yield to a much greater extent, from its particles not being in such close connection with each other, than the front plate could do before it broke, it stands to reason that that would give a very modified, if any, assistance to the front plate. That is the case with a piece of wood. A piece of wood will bear a squeezing up, a pressing before it reaches the ultimate point of breaking; it so moves away that a 44-inch plate would have to be distorted out of its form to a considerable extent before it could receive assistance from this piece of wood. That would necessarily cause it to break; consequently, it would receive no assistance whatever from this piece of wood. The wood, it is true, would be a second defence, it would prevent the shot going into the ship, but it would afford no assistance to the iron in preventing it from breaking. If instead of this piece of wood you put a piece of metal, whose particles are equally in close contact with each other as the particles of the iron plate itself, you would receive an assistance equal to doubling or repeating over again the amount of resistance of the iron plate itself, that is to say, if the front iron plate had a resistance of 4, the two together would give a resistance of 8; but if, instead of putting two, one as a support to the other, you made the whole in one plate of four inches thick, instead of a resistance of 8 you would have a resistance of 16, because you would have a resistance equal to the square of the depth of 4 inches, which would be 16. Therefore, by carrying the same weight on your ship's sides, you would get exactly twice the amount of resistance you would have with the iron backing; and that I have shown is much more effective than the wood backing.

Now

If you follow out that principle, by substituting for all that large amount of useless wood a plate in weight equal to the wood, then, with that and a 4 inch plate you would get a 6-inch plate. Incorporating that 6-inch plate into the top side of your ship, you first of all get an armour which will give you nearly double the amount of resisting power that you get in the present "Warrior." But you get a great deal more than that; you so reduce the weight by doing away with all the top side of the ship to which you hang all this armour, that instead of making the top sides of your ship weak you make them extra strong, by the top sides of the ship being both constructed of, as well as coated with, armour. You would be able to cover the vessel from stem to stern with a plate 6 inches thick and 5 feet below the water, and have 270 tons less weight, and your vessel would float 6 inches higher than the "Warrior" does at present, yet covered from end to end with armour. I ask, when such things can be done on an iron ship, and when any one analyses the way in which an iron ship is put together and the way in which a wooden ship is put together, can there be a doubt as to the comparative strength of the two structures, or a belief that iron structures will be done away with? Mark for one moment what necessarily takes place. In putting an iron ship together, if the thing is well put together, you really produce exactly the same result as if you had formed the entire structure of one plate of iron from end to end. You do not do that with a wooden ship at all. Every seam of the iron ship is rivetted and fastened together; and if properly done the strength of each seam is equal to that of the solid plate itself. Now in wooden ships the strength depends upon the strength of the fastenings which you put through the timbers. A very good plan when vessels are kept continually floating, and up to the time of iron ships the best plan you could get. But when we have arrived at a point where we are able to make iron vessels so strong, that we might make them, if necessary, equal to stand a pressure of fifty or sixty pounds to the square inch-for that is really the strength we might apply to iron vessels if properly put together-and where wooden vessels would not stand a fourth of that pressure without yielding in every direction, it is a little beyond the mark to talk of iron ships being unfitted to convey valuable lives. I would mention another instance with regard to iron vessels which you cannot hope to get with regard to wood. I recollect a vessel going down the river one day in a fog. She came back the next day to my works to be repaired, cut down by another steamer having run into her to four feet below the water's edge. The engines brought her back to the works. No part of her cargo was damaged. The accident was confined to the compartment which was struck-the bow compartment. That was full of water up to the water-line; but beyond that there was no water in any other part of the ship. Surely, these are advantages which are of no small amount. With regard to the vessel I told you of, the Paramatta, I believe at the time and for a long time afterwards, during which they hoped to save her, they got the water completely excluded from every compartment except the compartment in which the rocks had penetrated her bottom. I do not speak with certainty as to whether that was so in the first place, or whether that was the result of some additional security and help they gave to the bulk-heads afterwards. But, be that as it may, whether at first or afterwards, the bulk-heads in the ship enabled them to do this; and they did it so completely that for a long time the water flowed in and out only at that portion which was penetrated, and in no other part. I think the points we have got to deal with in this discussion resolve themselves very greatly, not so much into what was done some years ago, as into what has got to be done to complete our present doings with regard to these vessels. Though I have spoken thus strongly with regard to the observations and experiments which I have made, I would suggest, that the wisest course in this case would be merely to accept them as the result of so much observation, so much experiment, or so much speculation on the part of one who has had some opportunities of making some experiments and thinking a good deal upon the subject. I say, let experiments be tried. Let two or three targets, not of a small size, but of a very large size, be tried, having these different qualities of arrour placed before them. I fancy the whole thing resolves itself into this. The great question, the great point of anxiety, will be to determine which is the best way, when we have got these iron hulls, of dealing with them--whether to put one description of armour upon them, or to put another description of armour upon them. All I hope and sincerely wish is, that the result of these deliberations and discussions here will be, to convince the Government that the wisest, and cheapest, and quickest course will be to get an elaborate set of experiments made on several descriptions of armour as from a reasonable consideration of the matter seem likely to produce a good result; and then to avail themselves of the assistance of such of their officers as may be likely to lead them to a correct conclusion as to which of these kinds of armour is the best.

Evening Meeting.

ADJOURNED DISCUSSION.

Wednesday, March 20th, 1861.

CAPTAIN E. G. FISHBOURNE, R.N. C.B. in the Chair.

Capt. STOPFORD, R.N.-Capt. Halsted on Monday night referred to the experiments that were made at Portsmouth in 1850, and said that great secrecy was observed in regard to them, and that he could not find out the different results till some years afterwards. I happen to have been at the College at Portsmouth when these experiments were made, and I, in common with every other officer at the college, was allowed to go on board the "Excellent" to see them. I made my own notes at the time, and this morning I looked at my note-book again; and I must say I found that everything which Capt. Halsted said he had discovered so many years afterwards was confirmed by the note which I made at the time-particularly with respect to Capt. Moorsom's shells, which broke in striking, and exploded. I find, I said, "the powder flew to leeward in a black cloud." I believe, as I have said, that every officer at the College might have gone on board. There was no secret made of it. The subject was discussed commonly among the collegians, and the target, after it was brought ashore, was put up in the factory, and I made a sketch of it; and I am sure, if Capt. Halsted had been there at the time, and had gone to the college mess, he might have heard the subject talked about like any other subject, and he might have discussed the whole of it with the port-wine class afterwards. In looking to-day at the plan I made of the target, I find there was one thing that he did not mention. I saw that a 24-pound shot fired from a boat diagonally, so as to strike the iron at an acute angle, took out a large strip, and made an oval or oblong hole. One hole was 134 inches by 5 inches. I have nothing more to say, than that I was not aware of any secrecy at the time; and I could have told Capt. Halsted the day after the experiment everything that was carried out, without, to my knowledge, infringing the orders of Capt. Chads, the captain of the Excellent."

Capt. HALSTED.-With regard to Capt. Sullivan's statements in reference to the "Lizard" and the "Harpy," it is a matter of great surprise to me that I should be considered as illustrating the benefits and advantages of iron ships for the purposes of war. If I were to meet him here again, I should ask him to accept one of the printed copies of my first lecture, in which he will see that I refer to the most distinct evidence which exists in public documents, to show that those vessels were never intended for actual war-that they were expressly set off as not intended or built for actual war, but only for limited service with a limited armament, generally having reference to river duties upon the coast of Africa. During the river troubles which took place in South America, they were sent across there; and I believe I may take Capt. Sullivan's own evidence in confirmation of the manner in which they there did their work-especially the "Lizard." He says that he found her with so many feet of water in her hold; yet that vessel, six weeks afterwards, was engaged again, in a perfect state of repair, with the same batteries. He speaks also of the general impression which then obtained in that part of the world with respect to the unfitness of iron for ships of war, and speaks of it as something victorious, and so forth. I think that, in doing so, he merely exhibited a remnant of that same foundation error which existed when the first attempt to introduce iron into the Navy was made. People then really

and truly believed that, because a ship was made of iron, therefore an iron shot was bound to bow and respect her, and not do her any harm. It was in that sense especially that the grape-shot I referred to was sent home to show, as the record stands, that a grape-shot would go through a plate of iron. We now know, in consequence of the experiments which are published in this Blue Book that I have had occasion to refer to so much, that a plate is perfectly penetrable by grape shot, at a distance of 200 yards, from a 32-pounder with a 6-pound charge. But, if he had looked again at the statements made in this first lecture, he would also have seen that, by data supplied in this very Blue Book, where the proportionate resistances of certain thicknesses of iron and of wood are gone into, as proved by a series of experiments, that those resistances appear to bear the same relative proportion as the difference of the specific gravity of the two materials-a proportion of 1 to 8. And therefore, upon that calculation, the "Harpy" and the "Lizard," with their plates, to have had their equivalents in wood, would have represented a ship's side of a 3-inch planking; and Capt. Sullivan and all those who may have had experience in naval strife know perfectly well that wooden ships with 3-inch planking are not those which are practically considered as fit for the purposes of war. These vessels are not intended or expected to be. They are properly stated historically to have been a great number of tender-packets and small vessels, intended for limited service, and with limited armament. Such were both the "Lizard" and "Harpy"; but I maintain that, as far as their services went, they upheld most distinctly the objects and purposes which were had in view by the introduction of iron into our service in those days. It was not an increase of protection; it was to realize the advantages of iron instead of wood-all those material advantages which had been up to that time absolutely proved. And when iron was introduced for purposes of war, if there were no disability in the material beyond that presented by wood, then the object and purpose of those who introduced iron amongst us would have been fulfilled. It was never intended and never expected there is the most direct proof that there was an absolute disclaimer of it-it was never intended or expected by anybody that the shot would pay more respect to a ship of iron than a ship of wood, in proportion to the power of resistance of the two materials; but that mistake did occur. I have done all I could to endeavour to remove it, and put the matter upon its own true basis. Then again Captain Sullivan brings forward a statement which he heard about the two men, two officers, having been killed in the gun-room by the fragments of either the rivets or plating. It would have been more satisfactory, I think, if he had said that there were records in the Admiralty or elsewhere which I had not quoted, and which went to prove what he stated. What I have stated here with respect to the circumstances regarding the killed and wounded, has not been either attributed or attributable by those present to anything connected with the peculiar material of which the ships were constructed. I have taken my statements from the actual records in the Admiralty. They know of no others. There is the whole correspondence perfect and complete. I have examined the killed and wounded lists, and there is not the slightest reference whatever to any single soul having been injured in any way from any peculiarity in the material of the ship; and therefore in meeting the position which I have taken upon the face of the Admiralty records, I think Captain Sullivan was bound to have stated from what records he got his contrary statement; otherwise I think that it is a question of bona fide record against mere opinion, or rather a mere opinion against a bona fide record, and there is no substance in it; and I would refer again to what I have already stated in my first lecture. The very grape-shop that was sent home was said to have killed the man's brother; but the man whose brother is said to have been killed applied to the Admiralty and had the grape-shot given to him, not because he ever heard it had killed his brother, but he said, "I have seen a report in the Times that the shot which was brought home in a particular ship and sent to the Admiralty did kill my brother." That is the whole authority for it. There is not a single word in the letter of the commander with reference to the sending home the grape-shop, which shows that it killed anybody, yet he gives a most accurate account of everything that the unhappy grape-shot did, and everything that came in its way, and forgets to say that it killed the man. Everybody knows with what ardour these things were questioned at the time, and there was an express order sent out to the "Harpy" and the "Lizard" to make a report of what injury was done to them, especially as regarded their material.

That report became the subject of discussion in a particular place which I will not and need not name. There is not word in that discussion to say that a single person was wounded from any peculiarity in the material of the ship; but, even supposing that two men had been killed, and that two men had been wounded by a splinter, whether it were iron or whether it were wood, we have again only evidence of the same error, as if neither men nor officers had ever been killed by wooden splinters, and the only splinters that could kill men were those of iron! It only shows that one has to deal in a question of this sort with a very great amount of-I will not call it prejudice, but of prepossession, and that men have not taken the trouble to examine closely into the subject upon which they speak. With regard to the state she was in under water and so forth, I only mean to say that there we have a corroborative evidence of what is stated in Sir Howard Douglas's work, that they managed to plug all the shot-holes, and there she has been working ever since she has been with me, for the last three or four years up to January 1860, and is as sound as a roach at this moment. All her repairs were effected, and she was again in action with the very same batteries six weeks afterwards.

With regard to the question of the relative destruction of ships of iron and ships of wood when remaining on shore, Mr. Samuda in the first place answered my remarks, which would be more applicable upon a general view; but I am taking the question principally and almost entirely with reference to the Navy; but it is curious that Captain Sullivan, in speaking of the rapid destruction of the "Birkenhead," did make an allusion, I am aware, to the destruction of the unfortunate "Thunderbolt" very close upon the same locality. There was a pretty case of ripping in the case of the "Thunderbolt." The inspector of machinery, who was my great coadjutor at Sheerness all the time I was there, was the chief engineer of the "Thunderbolt," and upon his authority I can state, that so perfectly did the "Thunderbolt" rip herself up with the rock, that she ripped up one of her tanks inside. The rock entered the ship, and ripped up one of the tanks in the forehold, so that there was as tidy a little piece of ripping as could well be effected in the case of iron, and that was close to the same locality as that of the destruction of the "Birkenhead."

Now I have done with Captain Sullivan, and I address myself to the remarks which were made by Mr. Samuda. I perfectly agree with Mr. Samuda about his question of wood as a backing to plates. If we could by possibility get rid of it, it would be a great blessing, and I state this plain and simple fact and circumstance, as having forced itself upon my own mind, and I formed a strong impression from what I have witnessed myself, and which I mentioned the other day at the Institution of Naval Architects. The "Terror" was placed at my disposal during the greater portion, I may say, of the winter of 1856 and 1857, for the purpose of carrying on a series of steerage experiments outside of Sheerness to the north, and there we had to lay frequently, in very nasty bad weather.

I wanted to complete the experiments, and did not want to come into harbour. But I had occasion to notice, as I was looking over the side when we were rolling about at anchor, the quantity of water that got in between the plates as the ship rolled, it was one continuous water-spout along the whole length of the ship, the water was spouting out at every joint. Of course I could see from that circumstance that there was an enormous destruction of timber going on, and I am therefore perfectly alive to the value of doing away with the timbering as a backing to plates, if it can possibly be done, because I think that timber in that position is placed under very unfavourable circumstances; it is jammed to death between the two pieces of iron; there is the thick iron outside, the four-inch iron armour plate, and inside again there is the fiveinch plating of the actual ship. I referred in my lecture of Monday to the two drawings before you. I do not say the number of the shots are equal, but if anybody will look at them, he will see that they are fired at equal thicknesses of plate in the one case, without any timber-backing behind, and in the other case with the timber backing -the one being, as it were, a partial representation of the real side of the "Simoom," that is, the one without the timbering, and described in the Report-she being described as a frigate, and the other having the real and substantial filling and planking over that of the "Simoom " herself, and I think any person who looks at the drawing will see that the one set of holes are very irregular and broken. I do not mean to say that there is nothing approaching to an irregular hole in the case of the unbacked plate, but as a rule there is a marked difference between the one and the other, and a