This late afternoon, when the last of his jugs had been taken down and concealed by the spring, all ready for filling and carrying back the moment occasion should arise, Grenville felt that, save for a meat supply, he had made nearly every possible provision against attack and siege. The day was practically spent. He glanced at the sun. Undecided between an hour of hunting with his bow and a quick excursion down to the crypt of treasure, he remembered certain ornaments Elaine might wear and decided to go for the gold and gleaming jewels. They had meat for dinner, already being roasted in a sandpit with several newly gathered yams. Elaine, with a basket of tempting fruits, returned to the terrace from the thicket before he was ready for his trip. The fact that he bore a torch and basket aroused no query in her mind, so frequently had he made his underground excursions. He left the door at the gallery entrance open and made an easy descent. Glad to be independent of both the tide and his raft, he paused when he came to the main cave's ragged opening, for a moment thoroughly startled. The weird tidal wail had just commenced, so close at hand it echoed all through the place. It had never before occurred while he was actually in the cavern. Immediately rendered curious to see whence and how it was produced, he hastened down the outside ledge, completely baffled by the intermingled reverberations. He had barely concentrated his attention on a certain hole in the rock, below the tidal level, when the last uncanny moan seemed choked to a horrible gurgle which could not be renewed. The thing had never before been so brief or so abruptly ended. Its brevity jarred upon him no less unpleasantly than its prolongation had done when he and Elaine first arrived upon the island. As if the occurrence sounded a warning not to be mistaken, he proceeded at once within the cave. His mind was filled with thoughts of native visitors, who might only be waiting for this natural phenomenon to cease before they came swarming across the sea, perhaps to search and loot this very cavern. He reflected they might have searched it before, and had either been baffled by the water it formerly contained or had missed the niche his accidental interest had discovered. Though he thought that less than half the wall he had previously assaulted could now remain in the arch of the treasure cavern, yet fully a half-hour's labor was essential before he could worm his way inside where the gold and the stones dully glittered. He cleared out a few more stones to admit his carrying basket.