He tried his voice here, as in other parts of the cavern, but the walls gave back no unusual echoes. He was completely baffled, and, placing his lamp on the table, he sat down on one of the seats, to meditate on what course next to pursue. Lightfoot and Bill soon after, at his request, retired. He had been seated, he could not tell how long, with his head resting on his hands, when he was aroused by a yell more fearful, if possible, even than the groan that had so alarmed him on the previous night. The yell was repeated in the same horrible and mysterious manner that the groan had been. Flint sprang to his feet while the echoes were still ringing in his ears, and rushed to the sleeping apartment, first, to that of the Indian woman, and then, to that of the negro. They both seemed to be sound asleep, to all appearance, utterly unconscious of the fearful racket that was going on around them. Captain Flint, more perplexed and bewildered than ever, resumed his seat by the table; but not to sleep again that night, though the fearful yell was not repeated. The captain prided himself on being perfectly free from all superstition. He held in contempt the stories of ghosts of murdered men coming back to torment their murderers. In fact, he was very much inclined to disbelieve in any hereafter at all, taking it to be only an invention of cunning priests, for the purpose of extorting money out of their silly dupes. But here was something, which, if not explained away, would go far to stagger his disbelief. He was glad that the last exhibition had only been witnessed by himself, and that the men for the present preferred passing their nights outside; for, as he learned from Lightfoot, the noises were only during the night time. This would enable him to continue his investigation without any interference on the part of the crew, whom he wished to keep in utter ignorance of what he was doing, until he had perfectly unraveled the mystery. For this purpose, he gave Lightfoot and Black Bill strict charges not to inform the men of what had taken place during the night. He was determined to pass the principal portion of the day in sleep, so as to be wide awake when the time should come for him to resume his investigations. CHAPTER VII. On the day after the first scene in the cave, late in the afternoon, three men sat on the deck of the schooner, as she lay in the shadow of forest covered mountain. These were Jones Bradley, Old Ropes, and the man who went by the name of the Parson. They were discussing the occurrences of the previous night. "I'm very much of the captains opinion," said the Parson, "that the noises are caused by the wind rushing through the chinks and crevices of the rocks." "Yes; but, then, there wan't no wind to speak of, and how is the wind to make that horrible groan, s'pose it did blow a hurricane?" said Jones Bradley.