Full details were given to Admiral Mayo of the proposed North Sea Barrage on a line totalling 230 miles in length, which was divided into three parts, Areas A, B and C, of which Area A only would be dangerous to surface vessels. It was estimated that Area A would require 36,300 mines, and it was proposed that this area should be mined by the United States forces with United States mines. It was proposed that the British should mine Area B, the requirements being 67,500 mines, and that the United States should mine Area C, for which 18,000 United States mines would be required. The reasons governing the selection of the mine barrage area were fully given, and the advantages arising from the use of the United States pattern of mine instead of the British mine for Areas A and C were stated. Admiral Mayo was also informed of our intention to establish a mine barrage in the Channel, on the Folkestone-Grisnez line, as soon as mines were available, with a strong force of patrol vessels stationed there, whose duty it would be to compel enemy submarines to dive into the minefield. He was further made acquainted with our intended policy of still closer minelaying in the Heligoland Bight. Although Admiral Mayo was not actually informed of the details of the future policy which it was hoped to adopt in the Adriatic for the improvement of the Otranto Barrage, various schemes were at the time being worked out between the British, French and Italian Admiralties, having as their object the prevention or obstruction of the exit of enemy submarines from the Adriatic, in the same way as it was hoped to obstruct German submarines from making their exit from the North Sea without incurring heavy losses. The great depth of water in the southern part of the Adriatic constituted the main difficulty facing us in the solution of this problem. In August, 1917, it was, however, definitely decided to establish a barrage of nets and mines across the Straits of Otranto, and the work was put in hand. This became effective during 1918. The paper on Naval Air Policy showed the aim of the Admiralty to be: To provide in sufficient numbers a type of airship which would be able to scout with the Grand Fleet, and, in this respect, to perform the duty of light cruisers. Airship stations had been established on the East Coast for this purpose. To provide also a type of airship for coastal patrol work and for the escort of merchant ships in convoy. For these airships stations had been established on the East, South and West Coasts and at Scapa.