of the German navy, were giving the submarines this advantage. The British were most heroically struggling against the difficulties imposed by the mighty task which they had assumed. The British navy, like all other navies, was only partially prepared for this type of warfare; in 1917 it did not possess destroyers enough both to guard the main fighting fleet and to protect its commerce from submarines. Up to 1914, indeed, it was expected that the destroyers would have only one function to perform in warfare, that of protecting the great surface vessels from attack, but now the new kind of warfare which Germany was waging on merchant ships had laid upon the destroyer an entirely new responsibility; and the plain fact is that the destroyers, in the number which were required, did not exist. The problem which proved so embarrassing can be stated in the simple terms of arithmetic. Everything, as I have said, reduced itself to the question of destroyers. In April, 1917, the British navy had in commission about 200 ships of this indispensable type; many of them were old and others had been pretty badly worn and weakened by three years of particularly racking service. It was the problem of the Admiralty to place these destroyers in those fields in which they could most successfully serve the Allied cause. The one requirement that necessarily took precedence over all others was that a flotilla of at least 100 destroyers must be continuously kept with the Grand Fleet, ready to go into action at a moment's notice. It is clear from this statement of the case that the naval policy of the Germans, which consisted in holding their high seas battle fleet in harbour and in refusing to fight the Allied navy, had an important bearing upon the submarine campaign. So long as there was the possibility of such an engagement, the British Grand Fleet had to keep itself constantly prepared for such a crisis; and an indispensable part of this preparation was to maintain always in readiness its flotilla of protecting destroyers. Had the German fleet seriously engaged in a great sea battle, it would have unquestionably been defeated; such a defeat would have meant an even greater disaster than the loss of the battleships, a loss which in itself would not greatly have changed the naval situation. But the really fatal effect of such a defeat would have been that it would no longer have been necessary for the British to sequestrate a hundred or more destroyers at Scapa Flow. The German battleships would have been sent to the bottom, and then these destroyers would have been used in the warfare against the submarines. By keeping its dreadnought fleet intact, always refusing to give battle and yet always threatening an engagement, the Germans thus were penning up 100 British destroyers in the Orkneys--destroyers which otherwise might have done most destructive work against the German submarines off the coast of Ireland. The mere fact that the German High Seas Fleet had