The mouth of the cavern loomed like a great eye, growing gradually fainter and fainter as the daylight faded and the darkness grew outside. The river flowed by with a dull, roaring sound, and the little channel had risen from the entrance, and began to lap gently on the floor. The moisture dripped from the walls in loud-sounding drops, and the bats had awakened again, and flew to and fro towards the lantern with a soft whir of wings. When the last faint patch of light faded from the opening Bobby's bravery gave way, and the poor little fellow's tears chased each other down his cheeks as he crouched in a miserable heap on the damp ground.