ley_ was in charge of a subdivision of
trawlers carrying out a patrol in the vicinity of the Shipwash
light-vessel. At the close of the day the senior officer in the
_Burnley_, relying on the superior speed of his vessel to overtake the
others, ordered the two trawlers under him to proceed to their
anchorage in Hollesley Bay. What exactly happened after this will
never be known, but it is surmised that the _Burnley_ stopped to
investigate something suspicious. The _Holdene_, the senior of the
other two trawlers, reached the anchorage as night was setting in, and
had just dropped her anchor when a flash was seen on the eastern
horizon. This was followed by a dull, heavy explosion, which shook the
_Holdene_ from stem to stern. The anchor was immediately weighed and
the _Holdene_ steamed at full speed to the scene of the explosion;
but, though she cruised about for two hours in the darkness, nothing
was to be seen of the _Burnley_ or her crew. On the following day a
fresh group of mines was discovered in the vicinity, so it is probable
that the _Burnley_ had struck one of this group very soon after the
mines had been laid by German submarines.

Among the losses of the Harwich mine-sweepers may be noted that of
the paddle steamer _Queen of the North_, which was mined and sunk
while engaged in mine-sweeping. Despite the gallant efforts of her
consorts, one officer and nineteen men only were saved, seven officers
and twenty-two men being lost. Mine-sweeping in the War-Channel, as I
have explained, had to be carried out whatever the weather, and in
winter the weather conditions often made the work extremely hazardous.
For example, on one occasion a division had swept up eleven enemy
mines. Before any of these mines could be sunk by rifle fire a
blinding snowstorm swept over the sea, making it impossible for the
vessels to distinguish either each other or the drifting mines.
Nevertheless the R.N.R. officer who was in command of the division, by
exercise of good judgment, extricated his vessels from the dangerous
area, and twenty minutes later, when the weather cleared, he was
enabled to destroy all the mines.

One of the many dangers that attend mine-sweeping is caused by the
occasional failure of the sweep wire to cut a mine adrift. The mine
and its sinker come up the sweep wire when the latter is hove in, at
the great risk of causing an explosion under the vessel's stern. Thus,
the paddle steamer _Mercury_, while sweeping o