Smith stopped suddenly and grasped my arm. We stood listening. "What?" I asked. "You heard nothing?" I shook my head. Smith was peering back over the marshes in his oddly alert way. He turned to me, and his tanned face wore a peculiar expression. "You don't think it's a trap?" he jerked. "We are trusting her blindly." Strange it may seem, but something within me rose in arms against the innuendo. "I don't," I said shortly. He nodded. We pressed on. Ten minutes' steady tramping brought us within sight of the Thames. Smith and I both had noticed how Fu-Manchu's activities centered always about the London river. Undoubtedly it was his highway, his line of communication, along which he moved his mysterious forces. The opium den off Shadwell Highway, the mansion upstream, at that hour a smoldering shell; now the hulk lying off the marshes. Always he made his headquarters upon the river. It was significant; and even if to-night's expedition should fail, this was a clew for our future guidance. "Bear to the right," directed Smith. "We must reconnoiter before making our attack." We took a path that led directly to the river bank. Before us lay the gray expanse of water, and out upon it moved the busy shipping of the great mercantile city. But this life of the river seemed widely removed from us. The lonely spot where we stood had no kinship with human activity. Its dreariness illuminated by the brilliant moon, it looked indeed a fit setting for an act in such a drama as that wherein we played our parts. When I had lain in the East End opium den, when upon such another night as this I had looked out upon a peaceful Norfolk countryside, the same knowledge of aloofness, of utter detachment from the world of living men, had come to me. Silently Smith stared out at the distant moving lights. "Karamaneh merely means a slave," he said irrelevantly. I made no comment. "There's the hulk," he added. The bank upon which we stood dipped in mud slopes to the level of the running tide. Seaward it rose higher, and by a narrow inlet--for we perceived that we were upon a kind of promontory--a rough pier showed. Beneath it was a shadowy shape in the patch of gloom which the moon threw far out upon the softly eddying water. Only one dim light was visible amid this darkness. "That will be the cabin," said Smith. Acting upon our prearranged plan, we turned and walked up on to the staging above the hulk. A wooden ladder led out and down to the deck below, and was loosely lashed to a ring on the pier. With every motion of the tidal waters the ladder rose and fell, its rings creaking harshly, against the crazy railing. "How are we going to get down without being detected?" whispered Smith. "We've got to risk it," I said grimly. Without further words my friend climbed around on to the ladder and commenced to descend. I waited until his head disappeared below the level, and, clumsily enough, prepared to follow him.