Rock limpets and edible mosses abounded among them.
They were obstructed by quantities of shingle, heaped together in their recesses. Some of their huge smooth stones weighed more than a ton. They were of every proportion, and of every hue; but the greater part were blood coloured. Some, covered with a hairy and glutinous seaweed, seemed like large green moles boring a way into the rock.
Several of the caverns terminated abruptly in the form of a demi-cupola. Others, main arteries of a mysterious circulation, lengthened out in the rock in dark and tortuous fissures. They were the alleys of the submarine city; but they gradually contracted from their entrances, and at length left no way for a man to pass. Peering in by the help of a lighted torch, he could see nothing but dark hollows dripping with moisture.
One day, Gilliatt, exploring, ventured into one of these fissures. The state of the tide favoured the attempt. It was a beautiful day of calm and sunshine. There was no fear of any accident from the sea to increase the danger.
Two necessities, as we have said, compelled him to undertake these explorations. He had to gather fragments of wreck and other things to aid him in his labour, and to search for crabs and crayfish for his food. Shell-fish had begun to fail him on the rocks.
The fissure was narrow, and the passage difficult. Gilliatt could see daylight beyond. He made an effort, contorted himself as much as he could, and penetrated into the cave as far as he was able.
He had reached, without suspecting it, the interior of the rock, upon the point of which Clubin had steered the Durande. Though abrupt and almost inaccessible without, it was hollowed within. It was full of galleries, pits, and chambers, like the tomb of an Egyptian king. This network of caverns was one of the most complicated of all that labyrinth, a labour of the water, the undermining of the restless sea. The branches of the subterranean maze probably communicated with the sea without by more than one issue, some gaping at the level of the waves, the others profound and invisible. It was near here, but Gilliatt knew it not, that Clubin had dived into the sea.
In this crocodile cave—where crocodiles, it is true, were not among the dangers—Gilliatt wound about, clambered, struck his head occasionally, bent low and rose again, lost his footing and regained it many times, advancing laboriously. By degrees the gallery widened; a glimmer of daylight appeared, and he found himself suddenly at the entrance to a cavern of a singular kind.