to the imagination only by means of a Théâtre Guignol play. It was the obvious duty of the Q-ships to make the life of a U-boat as nearly as possible unbearable, and thus save the lives of our ships and men of the Mercantile Marine. It was no easy task, and even with perfect organization, well-thought-out tactics, and well-trained crews, it would happen that something would rob the decoy of her victory. On October 20, 1916, for instance, the Q-ship _Salvia_, one of the sloop-class partially reconstructed with a false counter-stern to resemble a 1,000-ton tramp, was off the west coast of Ireland when a submarine appeared astern, immediately opened fire, and began to chase. _Salvia_ stopped her engines to allow the enemy to close more rapidly, but the U-boat, observing this, hauled out on to the Salvia’s starboard quarter, and kept up her firing without shortening the range of 2,000 yards. _Salvia_ next endeavoured to close the range by going slow ahead and altering slightly towards the enemy, but the latter’s fire was now becoming so accurate that _Salvia_ was soon hit on the starboard side by a 4·1-inch high-explosive shell. This burst through in nine places in the engine-room bulkhead, smashing an auxiliary steam-pipe and causing a large escape of steam. The engines were now put full ahead, and course was made for the enemy, who sheered away and shortly afterwards dived. [Illustration: FIG. 7.—DIAGRAM TO ILLUSTRATE APPROXIMATE MOVEMENTS OF ‘SALVIA’ IN HER ACTION WITH SUBMARINE ON OCTOBER 20, 1916.] That being so, _Salvia_ deemed it prudent to pretend to run away, but in the middle of the evolution her steering gear unfortunately broke down, and before control was established again with hand-steering gear, the ship had swung 90 degrees past her course, and the submarine reappeared on the port beam about 1,500 yards away, but presently disappeared. The breakdown had been most unfortunate, for otherwise a short, sharp action at about 700 yards would have been possible, followed by an excellent chance of dropping a depth charge very close to the enemy. In that misty weather, with a rough sea and a fairly strong breeze, it had been difficult to see any part of the U-boat’s hull, for she had trimmed herself so as to have little buoyancy, and only her conning-tower could be discerned. Below, in the Q-ship, the engine-room staff found themselves up against difficulties; for it was an awkward job repairing the leaking steam-pipe, as the cylinder tops and the engine-room were full of live steam and lyddite fumes. The chief artificer and a leading stoker were overcome by the fumes, but the job was tackled so that steam could be kept up in the boilers.