Page 137 - British Inquiry into Loss of RMS Titanic Day 23 - 26

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24349. What system did you adopt in arriving at measurements above and beyond the scale figures which you find for ships in your scale C, and which you find for ships of the size, within the limits of Lloyd’s measurements; in other words, there are measurements in existence for ships of a certain size - we know that - and there are scale measurements. What method did you adopt in arriving at figures and measurements beyond that scale up to the size of the “Titanic”? - I have endeavoured to explain how I did it. It is a very difficult thing to explain. The Commissioner: He did explain it. He gave what he considers, and what I daresay is, a good explanation, but if you want to know whether I understood it, the answer must be “No.” Mr. Edwards: Probably, my Lord. The Commissioner: Did you understand it? Mr. Edwards: I follow your Lordship’s courageous example, and say “No.” The Commissioner: Did you understand it? Mr. Edwards: I did not fully understand it, my Lord. The Commissioner: I hoped you would say “Yes,” and then I was going to ask you to explain it to me. 24350. (Mr. Edwards.) One always sees the red light with you, my Lord. (To the Witness.) What I want to get at is this: Where do you take your figures or other measurements from for ships above what I call scale measurements? It is quite a simple question. As I understand you arrive at a definite conclusion as to the bendability of a ship of this size, and, therefore, to use an ordinary expression, you arrive at her total strength by a series of calculations? - Yes. 24351. And those calculations in their turn are based upon a series of measurements? - Yes. 24352. We know what the measurements are in the case of ships of a limited size. What I want to get at is, where do you get the measurements for ships and where does your Department get the measurements for ships, for the purpose of this calculation, for sizes above the scale size? - We got the measurements from the drawings of the “Titanic.” 24353. You have got the drawings there, and I will take two or three examples. You took the drawings of the “Titanic,” which show you that plates are of a given thickness in a given part of the ship? - Yes. 24354. Those plates presumably will be thicker in the case of the “Titanic” than in a ship of 10,000 tons? - Yes. 24355. What I want to get at is this. Take the case of the plates: by what system do you test the efficiency of the plates of extra thickness for a ship of this size as compared with the plates of a given thickness for a ship of 10,000 tons? - I do it in the manner I have already described. I treat the ship as a beam or girder. I assume that the tendency to bend the ship is equal to the displacement of the ship multiplied by her length and divided by 30, and I work out the stress in tons per square inch on the gunwale. Shall I give you the figure I arrived at, Sir? 24356. If it will help, certainly do so, please? - I arrived at a figure of 9.9 tons per square inch on the shear strake of the bridge of the “Olympic”. As I endeavoured to describe I drew out a smaller vessel having the scantlings of Lloyd’s Rules, and I treated her in exactly the same way, and I arrived in that case at a figure of 12.2 tons per square inch for a vessel having Lloyd’s scantlings, the inference being that the “Olympic” was stronger than the Lloyd’s vessel. 24357. That is to say, the “Olympic” for 46,000 tons was stronger per inch than Lloyd’s for 10,000 tons? - That is so, yes. Mr. Edwards: But you have no measurements of Lloyd’s for a ship of 46,000 tons. The Commissioner: He has said No. He has told us that so often. 24358. (Mr. Edwards.) And therefore there is no comparison between the two? - There is a comparison of stresses, but not of scantlings. 24359. In relation to this general calculation of the ship as a girder, did you consider how far the strength of the ship was detracted from by that hollow space where there are spiral stairs running