Frank, Billy, and Tom spread their blankets as near the fire as was safe, and rolled themselves in them. The bed was hard, but this bothered them little, and they were so tired that they were asleep almost as soon as they stretched themselves out. Bart, too, was more exhausted than he ever remembered being in all his life before, and from time to time he looked enviously at the forms of his sleeping comrades. The two hours that stretched before him would be very long ones. At times he would pace slowly about the room, stopping now and then to replenish the fire. His foot still hurt him a little, and he frequently sat down in a corner to rest himself. He found, however, that this was dangerous, for an almost uncontrollable drowsiness would steal over him, despite all his efforts to keep awake. The only way he could feel sure of staying awake was to keep on his feet. An hour passed and half of another. He was counting the minutes now before he would be relieved, when suddenly, as he was passing the entrance that opened on the corridor, he heard a sound that startled him. He stood stock still, every trace of sleepiness gone in an instant and all his faculties keenly on the alert. But nothing happened and he relaxed. "Pshaw!" he said to himself impatiently. "What's the matter with me? Am I letting what Tom said about ghosts get on my nerves?" Then the sound came again, and this time Bart knew that he was not mistaken. CHAPTER V CONSPIRATORS What Bart heard was the sound of human voices. At first the thought flashed across him that they might be those of some of his comrades, sent back by Lieutenant Winter to look for the missing men. But he dismissed this thought almost as soon as it was formed. There was a peculiar quality about the tones that was not American, a coarse guttural sound such as he had grown only too familiar with in the streets of Coblenz. Those who were talking were Germans. He listened intently. It was evident from the varying tones that there were quite a number of men in the group. At times the conversation seemed animated, and then again there would be a lull. Once he thought he heard them quarreling. What could these men be doing here in the dead of night? Was it possible that some part of the castle was inhabited after all? Or had they gathered together for some secret and lawless purpose? Bart thought at first that he would wake his companions and tell them what he had heard. On second thought, however, he concluded that he would do a little reconnoitering on his own account. They were so utterly tired that he hated to wake them for what after all might prove to be not worth while. Carefully looking to his weapons, he stole from the room and moved in the direction of the voices.