The rest of the evening was spent on the grassy knoll at one side of the enclosure, where Nathan and Godfrey related their adventures at Wyoming to an interested audience, and Barnabas and the sergeant discussed old times between whiffs of their pipes. At intervals Noah Waxpenny could be heard groaning dismally, or tramping up and down the narrow limits of his cell. At ten o'clock Sergeant Murdock went his round, posting one sentry inside the stockade gate and another at the rear of the fort, where a small window opened from the guard-room. A third was put on duty in the middle room of the block-house, with instructions to watch the prisoner's door. From the left of this middle room opened the big room where the privates slept, and on the right were the guard-room and the officers' quarters. To the latter's apartment, which contained a number of straw pallets spread on the floor, the sergeant led his guests. "All fixed, are you?" he said. "Good night, then, comrades." He blew out the candle, turned over, and was soon snoring loudly. A little later the slow and regular breathing of Godfrey and Barnabas told that they, too, were slumbering. Nathan envied them, for try as he would he could not induce the least symptom of drowsiness. For a long time he lay with wide-open eyes and active brain, thinking of the promised interview in the morning and listening to the occasional footsteps from the adjoining guard-room, where Noah Waxpenny seemed also to be possessed by the demon of wakefulness. When the lad finally did fall asleep from sheer weariness his rest was disturbed by hideous dreams. From one of these he suddenly awoke, relieved to find himself safe in the fort instead of battling with blood-thirsty savages out on the river. As he listened to the regular breathing of his companions he fancied he heard a low groan from outside, and almost immediately a rustling noise at the open door of the room fell on his ear. Closer and closer came the soft and stealthy sound, and the next instant, to the lad's unspeakable horror, the dark figure of a man kneeling on all fours rose at his very side, and a hand was passed gently over his body. Nathan's heart almost stopped beating, but by a tremendous effort he choked back the cry that was on his lips. For, at that moment, his eyes being partially accustomed to the gloom, he saw that the man held a glittering knife between his teeth; and he realized that at the first shout for help the blade would be plunged into his breast. He was terribly frightened, but by exerting all his will power he succeeded in doing what was best under the circumstances. He feigned sleep, and lay perfectly motionless. Not a muscle quivered, though cold sweat started on his face and hands. All he could think about was that glittering knife. It did not occur to him to wonder who the man was, or what he wanted.