The buoyant twist and roll which accompanied the lift and plunge of the _Upsal_, the frequent racing of her propeller, indicated that she was running in ballast. Almost for the first time in her drab, maid-of-all-work career, indeed, the _Upsal_ carried no cargo. She was on a special mission. A Scandinavian salvage syndicate, having come to an arrangement with the underwriters of a few out of the hundreds of vessels which strew the bottoms of the entrances to the British seas, had chartered her to locate and survey a group of promising wrecks, preparatory to more extended operations. The two young men were their technical engineers; Jensen, the taller of the pair, and Lyngstrand, his assistant. The third man, who stood aloof from them, was Captain Horst, the master of the ship. He was, of course, primarily responsible to his owners and not to the syndicate who had chartered his vessel. Until they reached the location of the wrecks the submarine engineers were merely passengers. Reticent and sombre as he had been since the commencement of the voyage, he ignored them now, stood apparently lost in abstract contemplation of the gray waste of sea. But one who could have looked into his face would have been impressed and puzzled by his expression. The cruel mouth under the little red moustache was curiously twisted. In the haggard eyes which roved around the restricted horizon was an oddly apprehensive uncertainty, unexpected in such a determined countenance. His glance looked down, apparently fascinated, upon the seas which raced below him as the _Upsal_ lifted on yet another crest, as though there were something strange in being so high above them--and then jerked up, automatically, to the horizon as in swift, instinctive doubt of impunity. A psychologist would have suspected that he allowed a fear of some kind, so long abiding as to have become a subconscious mental habit, the relief of free play when he knew himself unwatched. The two submarine engineers paid no attention to him. They gazed across the untenanted sea ahead to where the white spray leaped, almost lantern-high, in unsuccessful embraces of the tall column of The Bishop. Then, when the lighthouse, loftily unmoved above the eager seas, ascetically alone in the wide desolation of foam-streaked gray, had slipped abeam, had receded into the mist behind them, when there was no object to claim the eye on all the tumultuous stretch of ocean ahead, Jensen turned to his companion and pointed downward. Lyngstrand nodded assent, and they both staggered across the wet, reeling bridge toward the ladder which led below. The skipper, staring aft, his back on them, blocked their passage. Jensen touched him on the shoulder. He swung round abruptly, with a startled curse. Then, recognizing them, he moved aside grudgingly. His face was turned from them as they passed.