No doubt all ships are to some extent in danger from mines, but no other class of vessel is asked to run the gauntlet on the enemy’s coast to anything like the same extent. If surface ships are sent, they are sent for a single operation, the ground is prepared for them as far as possible, the period of exposure is short, and when the work is done the force is withdrawn. But our submarines are, for days and weeks at a time, close to known mine-fields and in areas most likely to hold new or drifted mines. They are harassed by hunters to whom they can make no reply, and particularly by aircraft, which can detect them even at sixty feet below the surface. The areas in which they work are comparatively narrow, and so closely patrolled by small craft that it is seldom possible to come to the surface in daylight; navigation, too, is very difficult, and the rapidly changing densities of the water off the enemy’s coast make the trimming of the boat and the depth control a matter of constant anxiety. Yet not only are officers and men found in plenty to enter this service of twilight and silence, but the keenness they show for it is unfailing. The work itself is their one ambition, and their records are astounding. Ask the Captain (S.) of this port. In two years he has organised 370 cruises, lasting in all 1680 days, and extending over a surface mileage of more than 200,000 miles. There was only a single breakdown, and that ended in a triumph; for the Commander got himself towed back by an enemy trawler, neatly captured for the purpose. Another--Commander Talbot--made twenty-one cruises; Lieutenant C. Turner, nineteen; Commanders Goodhart and Leir, seventeen each; Commander Benning and Lieut. C. Moncreiffe, sixteen. More wonderful still is the fact that the first two of these officers spent fifty-six and sixty-five days respectively in enemy waters, and the other four from thirty-six to forty-nine days each. The most interesting part of their adventures cannot yet be told; but much may be guessed from an outline or two. Commander Leir, for instance, was repeatedly in action with Zeppelins, seaplanes, and anti-submarine craft, one of which he sank. He was present at the action in the Heligoland Bight in August 1914, and brought home some German prisoners. Commander Benning was also repeatedly in action. Once, after torpedoing an armed auxiliary cruiser, he was forced by enemy sweepers to dive into a German mine-field. There he had to stay, with batteries exhausted, till night gave him a chance of recharging. Another time he went down into a mine-field of his own will, to lie in wait for an armed auxiliary. He was there for three hours, but ambushed her successfully in the end, close to the German coast. Lieut.-Commander Turner covered 20,000 miles to his own score, and passed much of his time actually in the swept channels, with enemy patrols in sight the whole day. Sometimes he came up and fought them, sometimes they hunted him with depth-charges.