At that moment I felt a hand touch mine. It was immediately withdrawn. The hand was cold, and the touch had been but a fractional pressure; but it was enough. I knew there was somebody there behind me; in the water it must be, for I was in the very stern of the boat. A horrible fear caught at my heart. It was bad enough to be held in captivity with my father's enemy in the lantern-light there before me; but this subtle, unseen creature, feeling up at me out of the dark water, was a thing to shake my nerve with a sense of inscrutable forces at work to undermine me unawares. I could scarcely concentrate my attention on the vital business in hand. But I must listen perforce, though with half my mind alert for the movements of that unknown presence at my back. The voice was speaking again: "You will either supply me with the missing clue, or"--he spoke with an ominous emphasis--"you will pay the penalty which the sign on your hand warrants." Still there was a stealthy jogging at my wrists. Casting desperately in my mind for what it could mean, and half afraid every moment to feel a knife in my back, I yet had a thought to give to the words of my captor. It all seemed clear to me now. Worthing had been right in his surmise, though he hadn't suspected the connection between my father's fate and the persecution of the Captain. It was a common enemy, I knew now, who being himself on the scent of the treasure knew that he needed both the manuscript which my father had possessed and the clue which only the Captain could supply, as he had already threaded the maze and stolen a share of the gold. But I was still in the dark as to how I could serve the fellow's turn. He resumed: "You have the choice. Behind you lies the shore and freedom; before you a sea-voyage and the forfeit at the end of it. I will give you two minutes to decide. I shall then ungag you and you will tell me the secret of the entrance. If you refuse you will be your own executioner." He took out a heavy watch, and repeated, "I give you two minutes." I was in an agony. Clearly he thought I knew the secret because I had lived with the Captain. He seemed to know I had once penetrated to the secret chamber; probably he presumed I had then learnt the answer to the riddle. My mind was in a maze. All I could see clearly was that I was in danger of sharing the fate of that wretched skeleton if I failed to satisfy the demands of these men. The forfeit.... I shuddered, remembering my alarming experience in the passage. How was I to convince this man that I was as ignorant as himself?