DISCUSSION ON TWO PRECEDING PAPERS. . 25 



official or officials to the necessity of appointing a committee to radically revise the existing 

 rules and regulations of the United States Steamboat Inspection Service. 



The Chairman : — Any further remarks upon these papers ? 



Rear Admiral Washington L. Capps, U. S. N., Vice-President: — I hope the meeting 

 will not be alarmed at my bringing some documents to the platform with me. I shall only 

 briefly refer to them and shall not take much of your time. I had hoped that this important 

 subject would be thoroughly discussed by the members of the Society. As one who has had 

 somewhat to do with the work of the recent International Conference on Safety at Sea, I con- 

 fess to a certain disappointment that the subject of the papers has been handled with so 

 much delicacy and restraint. I think this indicates, however, that those who studied it real- 

 ized that it was a much more difficult and complex question than might appear on the surface. 



To proceed immediately with comment on the paper, it is almost needless to state that 

 nothing in ship construction is more important than the preservation of the buoyancy of the 

 vessel in damaged condition. The Committee on Construction which dealt with this sub- 

 ject at the London Conference worked assiduously. At the very beginning there was very 

 far from being any general agreement as to the best means to propose. Three more or less 

 definite schemes had been presented by three of the most important maritime nations, but 

 none of these schemes had been sufficiently developed to permit definite and final determina- 

 tion as to its merits and demerits. As the deliberations of the Conference proceeded, it be- 

 came evident that we would have to strike out on new lines. The main Committee on Con- 

 struction was then subdivided, and these sub-committees were given specific subjects to con- 

 sider, with the result that before adjournment of the Convention this committee was able 

 to report a definite scheme. Even its most ardent advocates, however, would not claim for 

 it anything approaching perfection. Certain compromises were necessary, but it takes more 

 than a casual reading even of the complete report of the Convention itself to determine just 

 what are the good points and the weaknesses of the Convention that was finally adopted. 



I think I am safe in stating that the main question as regards buoyancy of vessels un- 

 der damaged conditions is the "permeability" assigned to different compartments of the 

 vessel, especially where these compartments are subject to varying densities of loading. 



The Convention finally adopted owes much to the labors not only of the original British 

 Bulkhead Committee of the early nineties, but also to German, French, and subsequent 

 British research and experience. It may not be known to many of our membership that the 

 "permeability" adopted by the original British Bulkhead Committee, whose technical labors 

 were so splendidly directed by the late Professor Jenkins, was 40 per cent. You will note 

 that, in the "permeabilities" adopted by the Convention, the lowest was 60 per cent. That 

 percentage was only applied to cargo space, whereas the percentage for machinery space was 

 80 to 85 per cent, and that for passenger and other between-deck spaces was 95 per cent. All 

 double bottoms were allotted a permeability of 95 per cent. A brief consideration of these 

 percentages for "permeability" show how, at the very beginning of our deliberations, we 

 greatly increased the factor of safety. The "permeability of a space" used in this sense is 

 the "percentage of that space which can be occupied by water" under the conditions assumed 

 in the calculations. This means that in all calculations resulting from the provisions of this 

 Convention you must assume that, no matter what your cargo is, 60 per cent of that total 

 space can be occupied by water; and, similarly, 80 per cent of the machinery space and 95 

 per cent of passenger and between-deck spaces. 



