in the North Sea
Barrage. Our own submarines accounted for some nineteen.

Our destroyers and patrol craft of all natures sank at least twenty by
means of gunfire or the ram, and some four or five more by the use of
towed sweeps of various natures. Our decoy ships sank about twelve; four
German submarines are known to have been sunk by being rammed by
men-of-war other than destroyers, four by merchant ships, and about ten
by means of our nets. It is fairly certain that at least seven were
accounted for by aerial attack. Six were interned, some as the result of
injury after action with our vessels.

The total thus accounted for is 156. It was always difficult to obtain
exact information of the fate of submarines, particularly in such cases
as mine attack, and the figures, therefore, do not cover the whole of
the German losses which we estimated at 185.

CHAPTER X

"PRODUCTION" AT THE ADMIRALTY DURING 1917

The anti-submarine measures initiated during the year 1917 and continued
throughout the year 1918, as well as those in force in the earlier years
of the war, depended very much for their success on the work carried out
by the Admiralty Departments responsible for design and production, and
apart from this these departments, during the year 1917, carried out a
great deal of most valuable work in the direction of improving the
efficiency of the material with which the vessels of the Grand Fleet and
other warships were equipped.

Early in 1917 certain changes were made in the Naval Ordnance
Department. When Captain Dreyer took up the post of Director of Naval
Ordnance in succession to Rear-Admiral Morgan Singer on March 1, the
opportunity was seized of removing the Torpedo Department, which had
hitherto been a branch of the Naval Ordnance Department, from the
control of the Director of Naval Ordnance, and Rear-Admiral Fitzherbert
was appointed as Director of Torpedoes and Mines, with two assistant
Directors under him, one for torpedoes and the other for mines. It had
for some time been apparent to me that the torpedo and mining work of
the Fleet required a larger and more independent organization, and the
intention to adopt a very extensive mining policy accentuated the
necessity of appointing a larger staff and according it greater
independence. The change also relieved the D.N.O. of some work and gave
him more liberty to concentrate on purely ordnance matters.

Captain Dreyer, from his experience as Flag