From below there rose a sullen, surging sound, the threatening monotone of angry waves breaking upon a rocky shore. The sound grew fainter. They must be travelling inland--across the Isle of Wight. Now, then, was the time for a descent. Dimly in the forepart of the boat, Wilton's bent form could be discerned, his face peering, his hands at work in the complex box of the _Bladud's_ machinery. Suddenly he threw himself back, sitting on his heels, and Herrick thought he saw his hands raised with a gesture of despair. The _Bladud_ lurched and swayed violently, and for a moment it seemed as if the gyroscope had wholly failed to act. If that were so, in a moment the boat might lose her equilibrium, and all would end. But that was not the trouble. Linton now realised that it was the lowering apparatus that would not work. The _Bladud_ still rushed madly forward. With unchecked speed, they flew across the island. Another coast line then came into view--the long low line of lights stretching from Portsmouth, across Southsea to Eastney and Fort Cumberland. There was hope, then, or if not ground for hope, at least a fighting chance! But the _Bladud_ now by some inexplicable perversity of the machinery made obstinately for the eastern extremity of the line of lights. That, again, might serve if only they could descend on the wide common of Hayling Island. They were nearing it every moment. Presently from below there rose a new menace, an angry sound--grating and monotonous, that Linton could not understand. "What's that?" he shouted. "The Woolseners," bellowed Wilton, in reply, and made a wild gesture with his disengaged hand. He knew the deadly peril--those shifting banks of shingle churned in the shallows by the ceaseless action of the tides and waves. The Woolseners were as fatal as the Goodwin Sands to every ship or boat that found herself among them. With a desperate effort, aided by Renshaw and directed by Wilton, Herrick forced over the helm. Another ominous crack reached their ears, but for the moment they were successful, and a sudden squall from the east aided their combined efforts. They now were heading straight for Portsmouth Harbour. All might yet be well! Still travelling at great speed, they traversed nearly half the distance, it now being Wilton's design to bring the _Bladud_ down on Southsea Common. Then, suddenly, the horizontal movement of the boat absolutely ceased. All the motive power that was left in her began through some terrible mishap to be expended in the development of rapid elevation. The frantic efforts of Wilton to check the upward rush were unavailing, the boat went up and up with terrible velocity. This last catastrophe was paralyzing, overwhelming. Climbing higher and higher, the boat would rapidly exhaust her small remaining store of compressed air. Then, in an instant, would commence a reversal, and the _Bladud_ would rush down through space--the end for all on board, inevitable death.