As they signified their readiness to start, the black lifted the door of a strange glassless lantern of beaten brass which, Pant was told, burned fish oil and would provide a feeble light for hours on end. After lighting the lantern he plunged boldly into the stream and led the way through icy water straight into the darkness of night until, with a grunt of satisfaction, he emerged panting and dripping upon a dry ledge where the cave suddenly widened to a broad chamber.
For a time, lighted only by the dull gleam of the Carib’s lantern, they moved along the brink of the narrow stream. The silence was oppressive. The stream flowed placidly over an all but level floor, making no sound. Only the gentle pat-pat of their bare feet disturbed the tomb-like hush that hung over all.
Then of a sudden, like thunder from a clear sky, pandemonium broke loose. The innocent cause of all the commotion was the Carib. He had, by chance, struck his lantern against a rock.
The air was filled with strange noises, such a whirring and snapping as not one of them had heard before.
“Wha—what is it?” Kirk’s hand trembled as he gripped Pant’s arm.
“Bats,” said Pant. “Stand perfectly still. They will settle.”
For a single second he threw on his flashlight and allowed it to play across the space before them. The other boy’s eyes went big with wonder. Even Pant, who had seen much of Central American life, was astonished. Bats, a million of them it seemed, circled the air. And such bats! No tiny mouse-like creatures were these, but great gray monsters with broad spreading wings, gleaming eyes and teeth that shone white in the perpetual night about them.
“Don’t.” Kirk’s hand was on his arm. The light flashed out.
“May as well go ahead,” said Pant. “Doubt if they go far back into the cave.”
They had not gone a hundred yards before they came to a very narrow passage. Once more they were obliged to take to the bed of the stream. This lasted only a moment. As they emerged there came over them a sense of vastness. Was it the quality of silence that was there? Was it the changed sound of their footsteps? Or was it some sixth sense that told them? As Pant threw the gleam of his powerful flashlight before them, an exclamation escaped every lip.