A terrific roar caused the man to break off suddenly. Somewhere within the radius of a mile, although the now increasing fog gave no indication of direction, an explosion of no slight magnitude had occurred. For nearly a minute came the sound of falling debris, and then deep silence. "Is that Fritz or us?" inquired one of the men, as the rowers resumed their task. "How far is it to Auldhaig?" asked another. "Lucky for us we aren't in the ditch. 'Twould be a longish swim." Wakefield let the men talk. It helped to keep up their spirits, although they were not apt to be down-hearted. For his part, he was kept busily employed in steering the boat by means of a small compass that was little better than a toy. By a fortunate chance, he had found it with a miscellaneous assortment of small articles in the inside pocket of his monkey-jacket. A fortnight previously he had been induced by an attractive damsel at a bazaar in aid of the Auldhaig Seamen and Fishermen's Society to buy what then occurred to him to be an utterly useless article, but now he found himself trusting implicitly to the doubtless highly erratic magnetised needle. It was a sorry substitute for the boat-compass that ought to have been in the boat, but wasn't; but even in the baffling fog Wakefield knew that he was provided with a means of direction. With reasonable luck, the boat ought to hit the Scottish coast somewhere, if the survivors were not picked up by one of the other patrol-boats known to be cruising in the vicinity. At frequent intervals Wakefield bade the men rest on their oars, taking advantage of the silence to listen for sounds indicating the presence of other craft; but beyond the lap of the water against the metal sides of the boat the stillness was unbroken. It was an eerie experience, climbing the slope of the long rollers and sliding down into the trough beyond, the while encompassed by a fog now so dense that at twenty yards sea and air blended into nothingness. Fortunately there was little or no wind, and the boat rode the swell without shipping as much as a pailful of water, but both Wakefield and Meredith knew full well that those sullen rollers portended a storm at no distant date. The while the pale rays of the moon penetrated with little difficulty the relatively thin stratum of fog overhead, the ghostly light adding to the weirdness of the scene. "Prop.!" exclaimed Kenneth laconically. A tense silence fell upon the boat's crew. Through the mists came the unmistakable thud of a vessel's propellers, but whether from north, south, east or west the baffling atmospheric conditions gave no clue. Then the subdued sound ceased abruptly. "Give a hail, lads!" exclaimed Wakefield; but before the bowman could stand and give vent to a bellowing "Ahoy!" the skipper countermanded the order. "We'll put a stopper on the hailing business," he remarked, without giving any further explanation. "Ah, there it is again!"