I think that the bases of the German submarines should have been attacked, and I so urged when the war was in progress; and one of my conferences with the British Admiralty in London in 1917 was to urge more active operations against the bases of the submarines. But it was an operation that had to be not only a concerted action, but the principal part of it would have been necessary to be taken by the Allies, we simply to add our part to it; and all during the summer of 1917, I urged active operations of that kind and could never understand why we did not get definite plans from the other side as to how such operation should be carried out.
While in London I agreed with Admiral Jellicoe on a plan, a very confidential plan, that was to be carried out later on, in which I not only volunteered to place our ships but insisted that our ships should be placed there.
During Benson's absence from Washington, Captain (later Admiral) W. V. Pratt in both 1917 and 1918 acted as Chief of Operations. In the discharge of that duty, as well as Assistant Chief of Operations, succeeding Captain Volney Chase, who died in the summer of 1917, Admiral Pratt demonstrated ability unsurpassed by any officer serving in any important position during the World war. When Captain Pratt later was ordered to sea, Admiral Josiah S. McKean, who had served with marked ability as Chief of Material during the war, became Acting Chief of Operations and added to his well-earned reputation.
Admiral Mayo, in his capacity of commander-in-chief of our ships in European as well as home waters, made an official visit to Europe in September, 1917, inspecting bases and forces, and conferring with naval leaders of Great Britain, France and Italy. He was on duty again in Europe in 1918. Attending the Allied Naval Conference in London, he urged the construction of the North Sea Barrage, which was shortly afterwards approved.
Visiting the famous Dover Patrol, he witnessed a bombardment of Ostend by British monitors, and had the experience of being under enemy fire. The flotilla leader Broke, in which he embarked with Sir John Jellicoe, First Sea Lord of the Admiralty, and other British officers of high rank, flew the flags of both Mayo and Jellicoe.
The monitors, armed with 15-inch naval guns, were accompanied on these expeditions by spotting aircraft and destroyers. The party accompanied the Terror. Soon after she began to fire, the German shore batteries got the range. Firing with precision and accuracy, some of the German shells fell within a short distance of the Broke. Admiral Reginald Bacon gives this interesting account of the incident:
On Tuesday, September 25th [1917], Sir John Jellicoe, Admiral Sir Henry Oliver, and Admiral Philpotts arrived at Dover and came with Admiral Mayo and his staff up the patrol line. It was a quaint experience for them. Half an hour after leaving Dunkirk in the Broke we lost sight of the shore. After an hour's steaming we sighted the Terror and destroyers in the open sea, and the motor-launches just starting their smoke-screen. Nothing else was in sight except a small monitor five miles away right out at sea, burning her searchlight for an aiming mark. Really our visitors must have thought we were humbugging when the Terror opened fire and fired single rounds at fixed intervals.
A few seconds afterwards while steaming about in the Broke—we had altered course three points—a splash came from a Tirpitz shell about 300 yards off. It fell very near the spot where we would have been if we had kept on our original course. I apologized to the American Chief of the Staff for not having kept on and brought the shell nearer. His reply was quaintly American in humor:
"Don't mention it, Admiral; by the time we get to New York that shell will have been close alongside right enough!"
The result of the Terror's shooting was most successful, as all the rebuilding in the dockyard done by the Germans was again demolished. On October 19th, the Terror was torpedoed, and had to be docked. On the following day the Soult fired at Ostend and destroyed a high explosive magazine. One German craft was sunk, and two more damaged.