158 Sir William H, White [June 9, 



surface and constitutes what is technically called a "reserve of 

 buoyancy." In the submersible this reserve of buoyancy and the 

 accompanying freeboard is greater than in the submarine type, and 

 in this respect lies the chief difference between the two types. The 

 submersible has higher freeboard and greater reserve of buoyancy, 

 which secure better seagoing qualities, and greater habitability. The 

 deck or platform is situated higher above water, and to it the crew 

 can find access in ordinary weather when making passages, and obtain 

 exercise and fresh air. Recent exhaustive trials in France are re- 

 ported to have established the great superiority of the submersible 

 type when the service contemplated may involve sea passages of 

 considerable length. The French policy, as recently announced, 

 contemplates the construction of submersibles of about 400 tons 

 displacement for such extended services, and proposes to restrict the 

 use of submarines to coast and harbour defence for which vessels of 

 about 100 tons displacement are to be employed. All recent British 

 submarines would be ranked as submersibles according to the French 

 classification, and it is satisfactory to know, as the result of French 

 experiments, that our policy of construction proves to have distinct 

 advantages. In addition to these two types of diving- or submarine- 

 vessels the French are once more discussing plans which have been 

 repeatedly put forward and practically applied by M. Goubet, namely, 

 the construction of small portable submarine vessels which could be 

 lifted on board large ships and transported to any desired scene of 

 operations. In the Royal Navy for many years past, it has been the 

 practice to similarly lift and carry second-class torpedo or vedette 

 boats about 20 tons in weight. Lifting appliances for dealing with 

 these heavy boats have been designed and fitted in all our large 

 cruisers and in battleships, and a few ships have been built as " boat- 

 carriers." The first of these special depot ships in the Royal Xavy 

 was the Vulcan ordered in 1887-8, the design being in essentials 

 that prepared by the writer at Elswick in 1883. The French have 

 also built a special vessel named the Foudre which has been adapted 

 for transporting small submarines to Saigon, and performed the 

 service without difficulty. Whether this development of small port- 

 able submarines wiU take effect or not remains at present an open 

 question, but there will be no mechanical difficulty either in the 

 production of the vessels themselves or in the means for lifting and 

 carrying them. M. Goubet worked out with complete success designs 

 for vessels about 26 feet long and less than 10 tons displacement, 

 with speeds of 5 to 6 knots, the trials of which have been very fully 

 described, but French authorities have not adopted the type, and no 

 decision seems to have been taken to introduce it. In this country 

 no similar action has been taken, and our smallest submarines weighing 

 120 tons cannot be regarded as "portable." Indeed, some leading 

 British authorities on submarines have indicated that experience is 

 adverse to the construction of vessels in which not more than two or 

 three men would form the crew, and on that ground have condemned 



