Quickly the news of the captured submarine's former activities was flash-signalled to the Calder, and with the least possible delay the information was transmitted by wireless to Great Yarmouth and Harwich.
Until the minefield was located and destroyed it was unsafe for any shipping to proceed to or from Yarmouth Roads.
Questions put to the U boat's crew elicited that the vessel was one of seven operating in conjunction with the raiding cruisers. While the German fleet was bombarding Yarmouth, the submarines--having on account of their slower speed set out on the previous day--proceeded to lay a chain of mines from the Would through Haisborough Gat, and thence to a point a few cables east of the Gorton lightship, thus completely enclosing Yarmouth Roads from the sea. The UC6--that being the designation of the prize--had just completed her task when she sighted the Calder approaching. Miscalculating her position, she had run her nose hard upon the shoal, with the result that her low compartment quickly flooded, thus rendering her incapable of keeping afloat.
It was not long before four mine-sweepers came lumbering northwards from Yarmouth, while others proceeded in different directions to "clear up the mess", as their crews tersely described the dangerous operations of destroying the mines.
The Calder, still standing by, had missed the northern limit of the German minefield by a few yards. Had she held on her former course the probability was that she would have bumped upon a couple of the infernal contrivances--for the mines were dropped in twos, each pair connected by a span of cable to make more certain of a vessel's bows being caught in its bight--and been blown up with the loss of all her crew.
The destroyer had been sent on particular service. Other side issues had demanded her attention, and, with the pluck and resourcefulness of British seamen, her crew had risen to the occasion. To them it was all in the day's work, with one ulterior motive--to push on with the war.
Deftly, the result of months of experience, the mine-sweepers set to work. With little delay the first of the mines was located, dragged to the surface, and sunk by means of rifle-fire. Others were destroyed in quick succession, two exploding as the bullets, made for the purpose of penetrating the buoyancy chambers, contrived to hit the projecting horns of the detonating mechanism.
In two hours, the trawlers having swept the whole extent of the Would, the minefield was reported to be destroyed.
"What damage ashore?" enquired Crosthwaite, as the nearest trawler sidled under the destroyer's stern.
"Precious little, sir, considering," replied the master of the mine-sweeper. "A few buildings knocked about and a score or so of people killed or injured. Might ha' been worse," and he shook his fist in the direction in which the raiders had fled.