The descent into the cave was a gradual one for forty or fifty feet. Beyond the opening the cavern broadened out and became much higher. At the end of the descent there was a drop of a few feet, and after this the flooring proved quite level for over half a mile.
"Have a care of de birds!" shouted Remora. He meant the bats, which were circling in all directions over their heads. Near the entrance the Dark Cave is filled with them, and sometimes they brush against the visitor with their skinny wings, producing anything but a pleasant sensation. It was a bat which had knocked out the eye of the native before mentioned.
On they went, over a flooring of dark stone, reeking with wet, mould and slime. Overhead hung stalactites of lime rock, tinged with various colors from the minerals which lie hidden in these mountains of Porto Rico. In one spot a stalactite had fallen, and they picked it up and brushed it off, to find it of a rainbow hue, beautiful beyond description.
"I should think those stalactites would alone be worth something," observed Bob. "They would make beautiful house ornaments, were they properly cleaned."
"They wouldn't stand the outer air long," answered Dick. "Such rock never does."
"Great Cæsar! what a cave!" exclaimed Don, after they had been travelling for a mile or more. "This is a regular underground world."
"You have not seen it all yet, señor," replied Carlos Remora. "Da werry long, werry broad."
All had their eyes open as they advanced, looking for a long, flat stone, with a cross cut upon it and the initials M. M. M.
Robert Menden had questioned Remora on this point, but the Porto Rican had assured him that he had never seen such a stone, and added that he doubted if there were any carvings in the cave. "Only werry few come here," he had concluded. "Most men afraid of de dark."
"It would be very beastly down here without a light," said Menden, as they paused in front of a yawning hole a dozen or more feet in diameter. "Where does that lead to, Remora?"