Someone was creeping noiselessly in! On tiptoe he crossed, and, seizing the bar of iron, sprang behind the door, his hand raised ready to fell any person who entered. The handle of the door was very slowly turned, but next second—ere he became aware of it—a strange thing happened. *CHAPTER XXI* *LOST DAYS* As the door of the room in which he was imprisoned slowly opened, and he stood ready to attack the new-comer and fight for his liberty, he became suddenly blinded and rendered utterly powerless by a burst of heavy grey smoke. He drew one whiff of it, and, reeling, fell senseless upon the floor. Then, as the fumes which had rendered him unconscious slowly cleared, there stood in the dim light a form wearing an exact replica of the white cloak and hood which Bernard Boyne used when he visited that upstairs room in Hammersmith. The window being broken, and now that the door was open too, the fumes quickly dispersed, yet Gerald lay there where he had fallen, pale as death, and breathing only slightly. "A heavy dose!" laughed the hooded man grimly. "He won’t get over it for quite a long time!" And then he turned and left, leaving the door still open, so that all trace of the poisonous vapour which he had released from a heavy iron cylinder should be removed. An hour later he returned, but without his cloak, for the gas-mask was no longer needed. He carried an electric torch, which he flashed into the white face of the unconscious victim. "You’ll soon go away—never to return!" growled the mysterious man aloud; and then suddenly by the reflection of the light his face became revealed. It was Bernard Boyne. "The fellow knows too much—and so does the girl!" he muttered to himself. "We must deal with her next. But she’s not yet dangerous. Still, as Lilla says, in our business we can’t afford to take any risks. So stay there for the present, my friend," he added. And bending he felt the prostrate man’s pulse in the professional manner of a medical man. Then, apparently well satisfied, he crossed the room, closed the window and, after locking the door outside again, descended the stairs. When young Durrant at last began to slowly recover his senses, he awakened to find himself seated in an arm-chair in a small and not uncomfortable cabin on board a ship. The vessel was rolling heavily, and ever and anon the waves swept up past the porthole, partially obscuring the light. He drew his hand across his fevered brow and endeavoured to think. But all was hazy, uncertain, and unreal. Was he still dreaming? he asked himself. He placed both his hands upon the arms of the leather-covered chair and felt them. No! It was no dream! He was on a ship at sea!