As the American vessels arrived, they were immediately placed on duty with convoys and as danger-zone escorts. The ships of the Allies were employed almost exclusively in the Mediterranean, with headquarters at Malta, and our naval vessels did nearly all the escort duty between Gibraltar and the United Kingdom. They also convoyed over 4,000 vessels in local Mediterranean traffic, or bound for Mediterranean and Far Eastern ports; ships supplying the American army through Marseilles, the French forces in North Africa; the Allied armies at Salonika; the British in Egypt and Palestine; and the forces of Italy. Soon after our vessels arrived in August, 1917, Rear Admiral H. S. Grant, British Royal Navy, senior naval officer in command at Gibraltar, drew up the plans by which the "H. G." (Home-Gibraltar) and "G. H." (Gibraltar-Home) convoys were organized between the United Kingdom and the Mediterranean. These also included ships bound to and from French ports in the Bay of Biscay and ships bound to the United States. Destroyers, sloops and special service vessels accompanied each convoy as a danger-zone escort through the Straits of Gibraltar to 10 degrees west longitude and there waited for, or met, an incoming convoy from England. Men-of-war acted as ocean escort to the convoys from that point to British waters, where they were met by a danger-zone escort at the end of the route. At the beginning of October, 1917, a system of fast convoys, sailing every sixteen days, between the United Kingdom and Port Said, and vice versa, was organized. These were met at a rendezvous in approximately longitude 10 degrees west by naval vessels which escorted them to Gibraltar, where they were relieved usually by ships from the Malta command, to take them through the Mediterranean. These convoys were joined at Gibraltar by ships of over 10-1/2 knots speed, which were taken out by relief escorts and joined the convoy off Europa Point. The first of the through outward-bound convoys, _O. E. 1_ (outward eastward) passed Gibraltar October 11th, and the first through homeward bound convoy, _H. E. 1_, passed on November 26th. By December most merchantmen which arrived at Gibraltar had been in convoy at one time or another, and it was possible to sail ships bound for North and South American ports in separate small convoys, with one master and commodore, escorted through the danger zone to longitude 10 degrees west. Between that time and the middle of February, 1918, 207 ships were thus sailed to the Americas.