was to use a combination of the last
three alternatives_ provided that _a satisfactory type of mine_ could be
produced in sufficient numbers and a sufficient supply of small craft
provided by ourselves and the United States.

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 th