He took the torch from Carl, and advancing towards the right wall of the cavern, showed, flowing out of it, through a black, arched opening, a river of inky blackness. It rolled, with scarce a ripple, slow, and solemn, and still, out of that impenetrable mystery, and swept along between the wall on one side and a rocky bank on the other. By this bank they followed it, until they came to a natural bridge, formed by a limestone cliff, through which it had worn its channel, and under which it disappeared. On this bridge they found Cudjo perched above the water with his torch.
They passed the bridge without crossing,—for the farther end abutted high upon the cavern wall,—and found the river again flowing out on the lower side. Few words were spoken. The vastness of the cave, the darkness, the mystery, the inky and solemn stream pursuing its noiseless course, impressed them all. Suddenly Virginia exclaimed,—
"Light ahead!" though Carl was with her, and Cudjo now walked behind.
It was a gray glimmer, which rapidly grew to daylight as they advanced.
"It is the chasm, or sink, where the roof of the cave has fallen in," said Penn.
While he spoke, a muffled rustling of wings was heard above their heads. They looked up, and saw numbers of large black bats, startled by the torches, darting hither and thither under the dismal vault. Birds, too, flew out from their hiding-places as they advanced, and flapped and screamed in the awful gloom.
To save the torches for their return, Cudjo now extinguished them. They walked in the brightening twilight along the bank of the stream, and found, to the surprise and delight of Virginia, some delicate ferns and pale green shrubs growing in the crevices of the rock. Vegetation increased as they proceeded, until they arrived at the sink, and saw before them steep banks covered with vines, thickets, and forest trees.
The river, whose former course had evidently been stopped by the falling in of the forest, here made a curve to the right around the banks, and half disappeared in a channel it had hollowed for itself under the cliff. Here they left it, and climbed to the open day.
"How strangely yellow the sunshine looks!" said Virginia. "It seems as though I had colored glasses on. And how sultry the air!"
She looked up at the towering rocks that walled the chasm, and at the trees upon whose roots she stood, and whose tops waved in the summer breeze and sunshine, at the level of the mountain slope so far above. She could also see, on the summit of the cliffs, the charred skeletons of trees the late fire had destroyed.