Beginning in April, 1917, with five officers and a {259} room or two, the United States Naval Headquarters in London had expanded, by the end of the war, to a total _personnel_ of 912 occupying several large houses--notwithstanding that, during the whole time, Admiral Sims himself had scarcely missed a single attendance at the usual daily conference at the British Admiralty. Under him at sea, and at the various subsidiary bases, with which we shall presently deal more particularly, there were serving by November, 1918, nearly 5,000 officers and 76,000 men. Not until it is remembered that these fifteen bases were scattered between Queenstown in Ireland and Corfu in Greece, between Inverness in the North of Scotland and Bizerta near Algiers; that every one of them had to be created while the war was in active progress, and that simultaneously, both in Europe and America, thousands of untrained men and officers had to be educated--can some idea be formed of the administrative miracle expressed in the full contribution of American sea-power. Declaring war in April, 1917, America's first naval units to appear in European waters were the destroyers that arrived in May to operate from Queenstown in the south of Ireland. Perhaps the most valuable of all, they arrived at a peculiarly appropriate moment. The submarine warfare was then at its most destructive stage; the British destroyer crews, at the end of their third winter, were beginning to show signs of staleness; while, owing to the demands upon them in every quarter and especially by the Grand Fleet, it had so far been impossible fully to develop the convoy-system of merchant shipping {260} later so successful. The arrival of these destroyers, therefore, was trebly welcome; and they placed themselves, without reservation, at the British Admiral's disposal. Reporting immediately upon arrival to Vice-Admiral Lewis Bayly, he enquired how soon they would be ready for duty. "As soon as we have re-fueled, sir," replied the Senior American Officer; and that remained the keynote of all their activities. By the end of June, twenty American destroyers were regularly at work in the Queenstown area; and, by the end of the war, though they were still under the British Admiralty, there were none but American destroyers at this base. Throughout that time, the bulk of their work consisted of escorting convoys; and the relief caused by their presence was felt almost immediately. It was in the Irish Sea, the Bristol Channel, and off the west coast of Ireland that our shipping losses had been heaviest; and our overworked destroyers had been obliged to fight the submarines by means of constant patrols in very broad areas. That had proved insufficient, as our losses clearly showed; and it was the American reinforcements that enabled us to turn the tide. The regular organization of convoys was at once put in hand, and the submarine sinkings began to decrease.