lew_,
with four armed trawlers. Fortunately the convoy was comparatively a
small one, for it was attacked and almost totally destroyed in the North
Sea by four of the largest German destroyers. H.M.S. _Pellew_, although
badly damaged, succeeded in returning to England.

It may be rightly thought that in both these cases the escorting
flotilla was not strong enough, but it should be remembered that if
heavier ships had been employed they would have been much less able to
cope with a submarine attack. The escort in both cases was purely an
anti-submarine defence, and only on the Scandinavian and Netherlands
routes was a surface attack at all possible, because all exits from the
North Sea were securely closed by the strategic positions occupied by
the Grand Fleet and the battle cruiser squadrons, in conjunction with
subsidiary fleets at Harwich and extensive mine-fields.

When it became apparent that surface as well as submarine attacks on the
North Sea convoys had to be provided against, other means were promptly
adopted, and no further disasters occurred.

The strong escort accompanying the transports bringing to Europe the
first American army were attacked at night by a submarine, but succeeded
in avoiding the torpedoes fired. This was due to the smartness with
which the United States warships were manoeuvred. Three subsequent
attacks on the same convoy route also failed.

The Report of the War Cabinet for the year 1917 gives some remarkable
figures in support of the convoy system. On the Atlantic routes about 90
per cent. of the ships were formed into fleets and escorted. From the
inauguration of this system the loss on these routes from all causes was
0.82 per cent., and if all the trade routes to and from the United
Kingdom are included, the loss was only 0.58 per cent. With these
figures in mind, who will deny that the navy is the surest form of
national as well as Imperial insurance?

FOOTNOTE:

[5] When writing of the navy in this connection due praise should be
given to the Mercantile Marine, which this war has proved to be a very
important part of the _true_ sea power of Great Britain.

CHAPTER X

THE MYSTERIES OF SUBMARINE HUNTING EXPLAINED

WHEN all is said and done, anti-submarine warfare is very like big-game
hunting. Success depends entirely on the initiative, skill and resource
of the individual hunter. Contrary to general belief, there is, at
present, no sovereign remedy for the depreda