UIT DE PERS.

445

Let him further imagine his chair and glass moving sideways as the effect of tide. Let him occasionally fill the room with steam to represent mist. Let him finally crumple the chart in ridges to represent the waves, and then try to carry out some of the manoeuvres which look so simple when the chart is spread out on the table and looked down upon in the quiet solitude of a well-lit study. I may be told that this is exaggeratiug the difhculties. This may be, but it is wise not to minimize the difhculties of the use of a new arm untried in war when the question of its superseding an old and tried form of naval weapon is at stake.

Let us, however, realize fully that submarine boats will undoubtedly exercise a vast influence on naval operations, both tactical ancl strategical, in the future. The extent can at present only be a matter of surmise, but it would be more than rash to assume that their success will be such as to lead to the disappearance of the fighting ship in the near future. That it will lead to the evolution of the battleship into the fast battle cruiser is probable, and that commerce protection and attack will assume larger proportions than invasion in future years owing to the defence of coasts by submarine boats is again likely, but, on the other hand, the idea of attack of commerce by submarines is barbarous and, on account of the danger of involving neutrals, impolitic.

Wheter very large submarines, in fact submarine cruisers, will become practical weapons it is impossible to say without extensive trial, since with increase of size the submarine lessens the present value of two of its main attributes, invisibility on the surface, which is of great importance to the initiation of successfull attacks, and invisibility below the surface on account of the wash produced by a large vessel at shallow immersion, or, if deeper immersion is ressorted to, visibility on account of the increased diameter of the periscope. It must ncver be forgotten that the larger the submarine the better the target she becomes for attack by torpedoes, and if her position below can be located approximately she becomes an easy prey to the torpedoes of destroyers and other vessels.

Let us not forget that naval operations must be carried out in all classes of weather and all conditions of atmosphere, at all distances from land, and that arguments as regards special waters and conditions cannot govern general operations when the fivc oceans become the theatre of war. Lord SYDENHAM stated that had the value of the submarine been appreciated Dreadnoughts would never have been built.