important. I should like to know presently from Mr. Scott whether he means to say that. It is obvious that if you test by making a hole for the drawing bolts in what you call the middle, you should take care it is really in the middle of the piece. Generally people do not test in that way, but they test by a clip which does not involve that source of error. It appears to me, with regard to the question of testing materials, that there is no safeguard except a final test to be applied whenever you think it necessary to apply it; and that you must, in the exercise of your own discretion, allow much of the material to pass without testing, inasmuch as you cannot possibly test every plate: that is out of the question. But somebody, either Mr. Scott or Mr. Kirkaldy, said that you always had the means of telling whether the pieces of material you put into a ship were good or bad when you worked them. Is that so? I ask any shipbuilder here whether there are not plenty of plates in a ship that never receive such an amount of work as would enable him to detect whether the plate was good or bad. I know perfectly well all our own overseers are in the habit of exercising their judgment upon it, and when you see a plate sheared, and when you see it punched (and our Chairman knows that as well as anybody in the room), you can tell pretty nearly whether you are dealing with good iron or bad; but you cannot be perfectly sure, from the nature of your punching and your shearing, whether you may not have in some cases a plate that ought not to go in. The Admiralty practice is this:-They say, "We must have some standard which 66 we shall apply when we like. We shall choose to allow you to put plates here, and angle irons there, 66 so long as we can satisfy ourselves by the work you put into them that the material is good, but "directly we say we want a test we must have the test." As I understand it, it is not the Admiralty alone that insist upon the tests, but Lloyd's surveyors do the same. How often they exercise it I do not know. That is in their discretion. I have seen a code of tensile strains in their books which may in their discretion be applied to iron, and it is bound to stand those strains. It seems to me there is no way to ensure having the ships well built, except by having some standard to be exercised within the discretion of the proper officers appointed to oversee the building of ships. It is amusing to hear Mr. Scott speaking as if there were no way in which ships could be built well except by having one or two inspectors independent of the builder himself, to see that they are well built. One would think, from what we have heard, that the credit of the builder (about which Mr. Lamport has spoken so much) would be something in the matter, as I believe it is. It seems to me that the course taken by Lloyd's surveyors is a wise and proper course. They do not test so often as we do. The iron does not cost so much money as our own iron costs; but I think that we and they would be quite wrong if we gave up the tests altogether. But now I should like to say one thing that will confirm what has been said by Mr. Martell, Mr. Lamport, and perhaps what Mr. Scott may think has been said by himself. I want to be perfectly honest in the matter. We took the trouble some time ago to purchase, from some private manufacturers of iron over the country, some iron according to a certain specification. They did not know for whom the order was given; but certain plates were all sent eventually to one spot, and there laid out side by side. It was of different prices. Some of it was a great deal cheaper than the price we were giving for that description of iron, and we were curious to know what sort of stuff it was which was called ship-plate iron, and I have to tell you that the iron was very good iron indeed. To that there was no exception, but in the matter of surface. In the matter of surface some was very bad, but in the matter of quality of material it was all good iron. But then I must say, and that may be some drawback, that it was all English iron. I confess I heard a statement some time since with regard to a fracture in the bow of a certain ship in Mr. Walker's dock, which made me draw in my horns

somewhat. I had been speaking confidently of the excellent character of the iron of which merchant ships are built, and I was asked whether I had seen the fracture of the iron in the bow of the Franconia. I had to say I had not. Then I was told it was a very bad fracture, and that the bow plates showed that the iron was not good. I believe the Franconia was built on the Clyde.

Mr. SCOTT: Yes, she was.

Mr. BARNABY: I have nothing to say about Scotch iron, except this, that we have some ships excellently built in Scotland, but we take care to tell our inspectors to keep their tests in their hands, and to insist upon having the tests applied whenever they please, and those excellent builders building those ships raise no difficulty whatever. They do not say, "What stupid people the Admiralty are to insist แ upon those tests;" but they go on, the iron passes very well, there is no grumbling, and we get thoroughly good ships built.

is

The CHAIRMAN: I think we have, perhaps, thrashed this subject out, and I am sure that you will feel with me that a great deal of useful information has been obtained; and the practical result of it all very much this, that if you want good ships, you must first go to a good ironmaster who never makes any but the best iron; secondly, to a good shipbuilder, who never puts any but the best possible workmanship in his ships; and thirdly, that it must be inspected under an inspector, like one of these very superior Lloyd's, and classed with the high class, and then you may pay your money and take your property, and everybody around you will prosper, and every one of you will have done his duty. That is a satisfactory conclusion at which to arrive. The other conclusion is, that no machinery and no legislation will make good ships out of bad iron, or clever and able and conscientious workmen out of ignorant or cheating persons.

Mr. SCOTT: Of course, in writing this Paper, I simply drew the line for classed vessels, or those vessels that are insured by underwriters at Lloyd's. They, of course, all look for some qualification in the matter, and, therefore, expect to have some guarantee. That is why I did not say anything in my Paper about going to a good builder, or knowing who was building the ship for you. Of course the underwriters-speaking on the matter from an underwriter's point of view-take Lloyd's Book as their standard in deciding whether they shall put £200 on a ship or £2,000.

Mr. C. LAMPORT: I say, as a practical underwriter, that we go by character more than anything else. The firm with which I am connected, as underwriters, will not take ships built in particular ports which I will not mention.

Mr. SCOTT: Quite so; but they may not be all like Mr. Lamport in this matter.

The CHAIRMAN: You are talking of classed ships?

·

Mr. SCOTT: Yes. It has been spoken of lately by Mr. Plimsoll. As to Mr. Martell's remarks about the surveyors, I may say that I did not include Lloyd's surveyors at all in the matter of inspectors. What I mean by inspectors are those men who are put to superintend a vessel, while building, by the owners, and who are very ignorant often, although they are supposed to be wise, because they are practical men or tradesmen. Every man is not a good constructor of a vessel who, as a tradesman, may know how to handle a chisel and hammer; and he is not always a man who is properly qualified to look after the construction of a ship. As to Mr. Martell's remarks about light ships, I did not for a moment

imagine that Mr. Martell would suppose that this light ship which I spoke of was a vessel bearing a greater strain per inch on any part than the iron would bear. That, of course, is the case with some of the light vessels that he has heard of being built in the Clyde. If Mr. Martell reckoned the section out, he would find that they, instead of having only a strain of 5 to 6 tons on the square inch, had from 10 to 12 tons on the square inch. Those are what we call light ships-useless ships; but the vessels I spoke of have from 5 to 6 tons on the square inch of strain—that is hogging and bending strain. Then, if we do away with this qualification, and put the responsibility on the builder, no doubt there are many builders, as well as myself, who would be at once able and willing to take the responsibility of the work they turn out of their hands. You will not find that everywhere. Owners say to us, "We can have such a vessel classed, and that class is quite as good to me as your ship; and, of course, we prefer not to spend that money upon her." That is how I spoke of the qualification. Then, as to Mr. Barnaby's remarks about the testing of plates—I mean plates as well as angle bars. Every second, or perhaps 60 per cent. of those tests are taken from plates, and you will find the results are exactly as I say. If you take a piece of iron out of the centre of a plate you will find that the most ductile part of the whole plate. Now, suppose you take the centre part of an iron plate, and test the ductility on the tensile strain, you will find the plate varies. The plate will stand 20 tons to a square inch in one part and 25 tons in another part, and so on like that. If any man condemned a plate of that kind out of an ironmaker's hands, he would immediately say, "Your test was not right; you gave me 20 tons to the square "inch in one part, 22 in another, and 25 in another; and my iron must be good, because one part of "the plate stands a higher test and the other does not." That shows the fallacy of the test. Then as to punching, I think if Mr. Barnaby were to go into the regular work of a shop, and see the punching and shearing of plates, he would at once find out whether it was a good or bad plate he was working. I have some specimens of iron cut off a common bar-an angle iron bar, that has been twisted in the cutting off, because of the head of the punching machine being close up and twisting the iron. Any one can see at once that it is beautiful iron, so that I think the working is the proper test for iron. You will excuse me, Mr. Barnaby, for saying these things, because I am a very much younger man than you are; and I am only talking from my own experience in iron shipbuilding, which I have been engaged in since I was quite a youth. Then, as to English iron, I am sorry to say that we in Scotland cannot produce the plates necessary for building ships, unless at a very much higher rate than we can get them for in England. Therefore you may safely say that two-thirds of the plates used in the construction of vessels in the Clyde are from England. As to the fracture in the Franconia's bow, I have heard something about that. She was constructed within 200 yards from my place; and if you took the plate that looks so bad in the Franconia's bow, and attempted to break it, no doubt you could break it with a 7-pound hammer, placing it over the edge of a block; but Mr. Barnaby must remember that that part of the Franconia's bow, before it gave way, was subject to enormous strain. The whole of the plating and the shell round the fracture was subjected to an enormous strain, thereby stretching the iron beyond its strength; and, of course, anything near the fracture must look bad. But, if you were allowed by the owners of the Franconia to take a plate out from the centre of the ship, you would find that the iron was as good as the iron in any other ships. I am only saying this from my own idea upon the subject. Then Mr. Barnaby spoke as if I had for a moment insinuated that the people at the Admiralty were at all stupid in demanding tests. I believe that is not to be thought of. Nobody would say that there was anything wrong as regards those tests; but only that it would not do to subject the vessels of the

mercantile navy to those tests, because we have not that amount of money to spend upon mercantile ships which is necessary to produce vessels intended for the Royal Navy.

The CHAIRMAN: I am sure we all feel indebted to Mr. Scott, of a very eminent firm, for the practical remarks he has made to us; and I am sure Mr. Barnaby will agree that practical experience and practical views, instead of interfering with what we do, always add to our knowledge and information. We are much obliged to Mr. Scott for his views, however they may differ from our own, because I think that views which differ from our own very often correct them.

ON DOUBLE AND TRIPLE CYLINDRICAL VESSELS.*

By H. A. EGERTON, Esq.

[Read at the Seventeenth Session of the Institution of Naval Architects, 6th April, 1876; JOHN SCOTT RUSSELL, Esq., F.R.S., Vice-President, in the Chair.]

In discussing the merits of ships composed of two or more hulls, it may not be out of place, in the first instance, to consider the size of waves which vessels may be required to encounter under varying circumstances and in different seas, since it must be evident, that a vessel which might be suitable for certain waters would not, to the same extent, meet the difficulties to be experienced in others.

Another matter of importance is the consideration of the particular objects to be obtained which would render it desirable to build vessels not in conformity with the usual shape and construction.

It is by no means intended to demonstrate that for ordinary purposes the present description of sea-going vessel is not admirably adapted for its different requirements; the intention being merely to show that, for certain exceptional cases, a totally different build may not only be desirable but necessary. Doubtless, for cargo-carrying, for the purpose of entering narrow harbours and winding channels, and for rendering the wind wholly or partially available as a motive power, little improvement could be made in shipbuilding as at present conducted; but where exceptional steadiness is required, and perfect ventilation must be obtained (as in carrying live stock great distances), ships of the present day are not of the most suitable type; and even where only short distances have to be travelled by water, but by large numbers of passengers (as between England and France), it seems almost incredible that all the discomforts of a sea voyage should have to be encountered, thereby actually debarring a large proportion of our population from visiting the nearest adjoining country.

Up to the present time there seems to have been a strange disinclination to venture upon any radical change in seafaring matters; and whereas during the last fifty years we

* Received 17th March, 1876.