That morning, when the party in the cavern had had their breakfast, with some hot tea made on a spiritlamp which Mrs. Cliff had brought, and had looked cautiously out at the sunlit landscape, and the sea beyond, without seeing any signs or hearing any sound of wicked men, there came a feeling of relief. There was, indeed, no great ground for such a feeling, but as the Rackbirds had not come the day before nor during the night, perhaps they would not come at all. It might be they did not care whether the black man ran away or not. But Captain Horn did not relax his precautions. He would take no chances, and would keep up a watch day and night.
When, on the night before, the time had come for Ralph’s watch to end, his sister had awakened him, and when the captain, in his turn, was aroused, he had not known that it was not the boy who had kept watch during his sleep.
In the course of the morning Mrs. Cliff and Edna, having been filled with an intense desire to see the wonderful subterranean lake, had been helped over the rocky barrier, and had stood at the edge of the water, looking over to where it was lighted by the great chasm in the side of the rocks, and endeavoring to peer into the solemn, cavernous distance into which it extended on the right. Edna said nothing, but stood gazing at the wonderful scene—the dark, mysterious waters before her, the arched cavern above her, and the picture of the bright sky and the tops of the distant mountains, framed by the sides of the great opening which stretched itself upward like a cathedral window on the other side of the lake.
“It frightens me,” said Mrs. Cliff. “To be sure, this water was our salvation, for we should have been dead by this time, pirates or no pirates, if we had not found it. But it is terrifying, for all that. We do not know how far it stretches out into the blackness, and we do not know how far down it goes. It may be thousands of feet deep, for all we know. Don’t go so near the edge, Ralph. It makes me shudder.”
When the little party had returned to the cavern, the captain and the two ladies had a long talk about the lake. They all agreed that the existence of this great reservoir of water was sufficient to account for the greenness and fertility of the little plateau outside. Even if no considerable amount of water trickled through the cracks in the rocks, the moisture which arose from the surface of the water found its way out into the surrounding atmosphere, and had nourished the bushes and vines.
For some time they discussed their new-found water-supply, and they were all glad to have something to think about and talk about besides the great danger which overhung them.
“If it could only have been the lake without the Rackbirds,” said Mrs. Cliff.
“Let us consider that that is the state of the case,” remarked Edna. “We have the lake, and so far we have not had any Rackbirds.”