The bases at the Azores and at Gibraltar, where we maintained a considerable naval force, were provided with all the necessities for our cruisers, destroyers, submarines, chasers and other small craft which joined the Allied navies in the policing of the Mediterranean and the adjacent Atlantic waters where we coöperated in the hunting of the undersea enemy and the protecting of transport and merchant craft. Several of our battleships and cruisers worked with the Italian Navy in Mediterranean waters. American sub-chasers gave important aid in the battle of Durazzo, in which they were given the advance post of honor and, preceding the Allied fleet, went forward picking a way of safety for the larger vessels through the thickly strewn mine field. Inside the harbor they shared in the battle, aiding in the attacking and sinking of Austrian steamers, destroyers and submarines. Assisting in mining operations and in the construction of a mine barrage was another of the important works of this group of submarine chasers in the Adriatic Sea. Several naval bases were established along the coast of France and through the last year of the war seventy vessels, of which half were destroyers, operated in these waters, their chief duty being to meet the convoys of American troop and cargo ships and escort them through the danger zone. They also worked up and down the French shores, hunting enemy submarines and escorting coastwise shipping. At all these repair and supply bases it was necessary to provide extensive facilities; a number of huge fuel oil tanks were built, most of the new destroyers and many other ships being oil-burners; several naval hospitals were constructed; a dozen naval port offices were established, from Cherbourg to Marseilles, to expedite the movements of American shipping through as many ports; naval aviation stations were built; rescue tugs and a wrecking steamer watched for and assisted damaged vessels; minesweepers kept open the approaches to the ports.