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December, 1914 spring meetings of the Institution of Naval Architects, a paper was read by Mr. P. Brimblecombe, dealing with the stability of ships in damaged con- ditions. The author considered a stan- dard vessel 400 feet in length and 48 feet in breadth, using four depths of 32, 27, 22, and 17 feet to the bulkhead deck, and two drafts for each depth. The drafts taken for the 32 feet depth were 23 feet 4 inches and 26 feet. It will be seen from these figures that a good range of possible vessels was covered:. ) The careo.. was. taken. as stowed in three distinct ways as- fol- lows:--(a) Homogeneously distributed throughout, (b) concentrated in the lower holds, (c) filling the compart- ments to just below the flooded water- line. The maximum damage assumed was just sufficient to sink the vessel to the margin of the safety line as de- fined by the Bulkhead Committee of THE MARINE REVIEW size the vessel, but she would probably heel over and render the launching of ~ the lifeboats very difficult. This actually happened in the Wilson liner Runo after striking a mine. It should be mentioned here that the results of the paper are based on the assumption of a reasonable stability for the ship in the undamaged condition. Capsizing After Damage It is very remarkable that | shortly after this strong expression of opinion, based on practice, some four or five vessels should have capsized after re- ceiving damage. In considering these vessels, it will be seen that all large passenger steamers present the case of a ship with cargo concentrated in the lower holds. For damage amidships the machinery can be treated as cargo of this nature, and the passenger accommo- PROMENADE DECK OF THE KONIGIN EMMA 1890. For homogeneous cargo the author found that for both drafts and for all depths, the vessel possessed positive sta- bility after flooding. With the other two cargo distributions he found that the vessel possessed negative stability after flooding, except in three cases. Two of these occurred for the deepest vessel at 26 feet draft, with cargo as in (b) and (c) respectively, and the third for the vessel of 27 feet depth at 26 feet draft and cargo as in (b). It is there- fore apparent that vessels with a homo- geneous distribution of cargo are safe from capsizing if they receive damage that would not sink them bodily, but the same cannot be said of those with the other arrangemets of cargo. It does not follow that the negative stability would be always great enough to cap- dation on one or more decks below the bulkhead deck necessitates the carriage of cargo in the lower holds. This con- dition of the vessel is opposed to safety against capsizing after bilging, but pro- vision can be made for it, and the rarity of instances of this kind shows that the danger can be, and generally is, obviated. There is reason to believe that the initial stability of the Cap Tra- falgar was none too good, and even a small loss would have been sufficient to render her unstable. The actual loss was certainly not small, and proved to be all sufficient to capsize her. There can be no doubt but that the initial sta- bility of the lost cruisers was ample, that is, when considered for ordinary sea-going 'purposes without reference to damage, more especially in view of the 449 minute watertight subdivision of these vessels. In war vessels with side armor such as the three cruisers possessed it is cus- tomary to investigate their -- stability assuming the unarmored ends riddled and open to the sea, in order to ensure its sufficiency. In making these calcu- lations, the protective deck at the ends of the vessel, just below the waterline, is assumed to be unpierced. It was the practice in some warships, for example the Inflexible, to provide cork packing or similar material at the unarmored ends to assist the stability in the same manner as cargo in the region of the flooded waterline assists it. Watertight Subdivision It is advisable at this stage, before analyzing the causes that operated in capsizing the three cruisers, to consider the possible methods of watertight subdivision, and their effects on sta- bility after damage. Three methods can be adopted, separately or in con- junction; they are transverse, longi- tudinal, and horizontal subdivision. The case for transverse subdivision was well stated during the discussion on the pre- ceding paper to the above, by Mr. Whiting, who said, "I believe it is not too much to say that, for the purpose of assuring a reasonable degree of safety in merchant ships, transverse watertight subdivision is always essen- tial, is generally sufficient, and, for many ships and classes of ships, is all that one can expect.' For intermediate and cargo ships any other kind of subdi- vision would make a very inconvenient, ™ if not impossible, arrangement, and viewed by the results obtained in the above paper would be unnecessary, since at drafts approaching the deep load the cargo would be more or less homo- geneously distributed, and extend to the flooded waterline. Longitudinal sub- division is of great value provided two conditions are fulfilled. It is necessary that any watertight doors in the lon- gitudinal bulkheads should be closed when the damage occurs, and that the water should find ready access across the ship to the corresponding compartment on the opposite side. If the wing longi- tudinal compartments are used as coal bunkers, watertight doors must be fitted, and it is very doubtful if these could be closed quick enough to prevent the stokehold from being flooded. Any passage ways for the flow of water across. the ship would probably be choked by coal, and the water on one side only would place the vessel in great danger from capsizing. The horizontal method of subdivision, by watertight decks, has the great vir-