I don't know why it had not occurred to me till then that he might have gone ashore, but somehow or other the discovery took me utterly by surprise. During the whole time that I had been on the island he had never yet left me alone without first coming to ask my permission, and I suppose I had begun to regard this as a kind of inevitable rite. At least I can think of no other way to account for the sensation of aggrieved astonishment with which I remained there gazing round the deserted shed. Being eventually struck by the futility of my proceedings, I came out on to the landing-stage, and stepped forward to the very edge of the water. In all directions a solid blanket of grey mist stretched before my eyes, while, except for the sound of my own footsteps, everything was as silent as the grave. That Bascomb should have deserted me in this extraordinary fashion was a thing which even now I found it hard to believe. There was only one conclusion to be drawn from the evidence, however, and that was that as soon as he had heard me return he had slipped away quietly with the extra key of the boat-house and had gone off alone in the dinghy. Why he should have chosen my dinner-time for his excursion was a mystery, but, queer as he might be, I felt convinced that he must have had some very definite purpose at the back of his mind. I tried to put myself in his place, and all of a sudden a startling but far from impossible idea suggested itself. Supposing he had gone to the barge! Supposing that, in his mad fury at the death of Satan, he had set off single-handed to try to wreak his vengeance upon Manning and Craill! Straining my eyes, I stared vainly through the mist in the direction he would have taken. If I were right there was no saying what cheerful work might even now be in full swing, for I knew enough of all the three principal actors to be quite certain that none of them would stick at trifles, and yet, without a boat, I was powerless to interfere. Until Bascomb returned or somebody else came over from Pen Mill I was as much a prisoner as Napoleon on St. Helena. At the very moment when this unpleasant truth was forcing itself into my mind the almost uncanny stillness was broken by a low whistle. I turned round sharply, and then six times in quick succession the same sound repeated itself from somewhere close about me. It was the call of a whimbrel--that queer, mournful note which, according to every fisherman along the east coast, is the sure herald of death or disaster. For a sailor I don't think I am particularly superstitious. All the same, there was something so weird and ominous in that unexpected cry that just for an instant I felt as if a cold hand had suddenly been placed against my heart. Then, by a big effort, I managed to pull myself together. With a kind of impatient anger at my own idiocy I stepped down off the landing-stage, and, walking back to the boat-house, had another look at the interior.