its reintroduction when
the submarine campaign developed. There is one inherent disadvantage in
this system which cannot be overcome, although it can be mitigated by
careful organization, viz. the delay involved. Delay means, of course, a
loss of carrying-power, and when tonnage is already short any proposal
which must reduce its efficiency has to be very carefully examined. The
delay of the convoy system is due to two causes, (a) because the speed
of the convoy must necessarily be fixed by the speed of the slowest
ship, and (b) the fact that the arrival of a large number of ships at
one time may cause congestion and consequent delay at the port of
unloading. However, if additional safety is given there is compensation
for this delay when the risk is great. One danger of a convoy system
under modern conditions should be mentioned, viz. the increased risk
from attack by mines. If ships are sailing singly a minefield will in
all probability sink only one vessel--the first ship entering it. The
fate of that ship reveals the presence of the field, and with adequate
organization it is improbable that other vessels will be sunk in the
same field. In the case of a convoy encountering a minefield, as in the
case of a fleet, several ships may be sunk practically simultaneously.

During the year 1916, whilst I was still in command of the Grand Fleet,
suggestions as to convoys had been forwarded to the Admiralty for the
better protection of the ocean trade against attack by surface vessels;
but it was pointed out to me that the number of cruisers available for
escort work was entirely insufficient, and that, consequently, the
suggestions could not be adopted. This objection was one that could only
be overcome by removing some of the faster merchant ships from the trade
routes and arming them. To this course there was the objection that we
were already--that is before the intensive campaign began--very short of
shipping.

Shortly after my taking up the post of First Sea Lord at the Admiralty,
at the end of 1916, the question was discussed once more. At that time
the danger of attack by enemy raiders on shipping in the North Atlantic
was small; the protection needed was against attack by submarines, and
the dangerous area commenced some 300-400 miles from the British
Islands. It was known that unrestricted submarine warfare was about to
commence, and that this would mean that shipping would usually be
subjected to torpedo attack f