es
might not be released from the bottom and rise to a depth at which they
were dangerous, _after the channel had been swept and reported clear_.
To deal with this danger a chain-sweep to work on the bottom was
introduced, but its use presented many difficulties, especially over a
rocky bottom.

When a regular swept and buoyed channel was in use the enemy had little
difficulty in deciding on the positions in which to lay mines by reason
of the presence of the buoys. This fact constituted the principal
disadvantage in the use of a buoyed channel, but in certain places where
the traffic was heavy the procedure was inevitable, and it greatly
simplified the work of the patrol craft and minesweepers; the only
precautions possible lay in the use of alternative marked channels, and
in the laying of defensive deep minefields outside the channel in which
enemy submarines might compass their own destruction. As rapidly as our
supply of mines admitted, this latter device was adopted in positions
where the minefields could not constitute a danger to our own
submarines. False buoyed channels with mined areas round them could also
be laid in which to catch the submarine. Another device was that of
altering the position of light vessels and buoys with the object of
putting a submarine on to a shoal.

The situation with which our patrol and minesweeping craft had to deal
having now been stated, it remains to speak of the magnificent manner in
which they accomplished their task.

I regret very deeply that, in spite of a strong desire to undertake the
task, I have neither the information nor the literary ability to do
justice to the many deeds of individual gallantry, self-sacrifice and
resource performed by the splendid officers and men who manned the small
craft. No words of mine can adequately convey the intense admiration
which I felt, and which I know was shared by the whole Navy, for the
manner in which their arduous and perilous work was carried out. These
fine seamen, though quite strange to the hazardous work which they were
called upon to undertake, quickly accustomed themselves to their new
duties, and the nation should ever be full of gratitude that it bred
such a race of hardy, skilful and courageous men as those who took so
great a part in defeating the greatest menace with which the Empire has
ever been faced.

There are, however, just two cases in 1917, typical of many others,
which I cannot forbear from mentioning.