"That's my idea, too," chimed in Walt. "Can't account for it in any other way. But what is 'here'? Where are we?" "You can answer that as well as I can," was the rejoinder. "Anybody got a match? Oh, here; all right, I've got some, plenty in fact--a whole pocketful." Jack struck a lucifer, and as its yellow glare lit up their surroundings, they could not repress a cry of astonishment. They had landed at the foot of a steep flight of stairs, at the summit of which they correctly surmised was the trap-door through which they had been so startlingly dumped. "Good gracious, did we fall down all those?" murmured Ralph, rubbing his elbow painfully. "Guess so. I know I feel as if I'd been monkeying with a buzz-saw," same [Transcriber's note: came?] from Walt Phelps. "Well, fellows," said Jack, as the light died out, "the question now before us is, what are we going to do?" "Try to get out again," said the practical Walt Phelps. "All right, Walt. Then we'd better remount those steps--slower than we came down them--and try to reopen that trap-door. We can't leave Pete and the injured professor like this." The boys clambered up the steps without difficulty. They were deep and shallow, and were cut out of the living rock. At the head of the stairs, however, a disappointment awaited them. Try as they would, they could not discover any means of reopening the stone trap-door in the floor of the hollow altar. Apparently, after dumping them through, it had closed as hermetically as before. The flickering light of the matches from Jack's store illuminated looks of despair on their faces as they realized that they were trapped. "Try pounding on it and shouting," suggested Ralph. Although Jack deemed it of little use, he and Walt followed this suggestion, and together the three boys beat and hammered on the massive stone above them till their hands were raw. There was no response, however. Apparently the stone was too thick for a sound to penetrate to the outer air. Terror, that was almost panic, seized Walt and Ralph, as they realized that they were prisoners in this hermetically sealed dungeon. Worse than prisoners, in fact. Prisoners had food and at least hope. They, unless they could find a way out, were buried alive. Even Jack's stout heart experienced a deadly feeling of depression, as he realized this. He concealed his despair from his companions, however, and, with all the cheerfulness he could muster, addressed them in the darkness. Matches had now grown too precious to squander. "Well, fellows, we've got to find another way out." "Oh, it's no good," moaned Ralph despairingly, "we're doomed to die here. We might as well sit down and wait for death to come."