“Fellows, look here!” he shouted. “Here’s a big cave leading right into the hill!”
Through the rain, splashing over the soaked ground, came Bob and Jerry, the professor following. They stood grouped about a hole in the slope—a hole large enough to permit a man to enter upright.
“Let’s go in and see what’s there,” proposed Bob.
“I guess it’s safe,” came from Jerry. “There are hardly likely to be any bears on this island.”
Together they advanced into the cavern. It was dark, but their eyes soon became somewhat accustomed to the gloom.
“It’s too big to explore without a light,” remarked the professor. “This may be a place for valuable relics. Let’s fasten the airship, and then come back with electrical torches.”
They turned to go, but, as they did so there came a sound which startled all of them. It was the sound of a human voice and, in cracked tones, as if the speaker had not used his vocal cords for some time.
“Who are you? What do you want?” was demanded in hollow accents. And then there came a faint glimmer of light, and in the rays of it they beheld a man—apparently a very old man—with matted beard, tangled hair and hollow, sunken eyes, who stood staring at them from the depths of the cave.