"Hallo!" cried Pencroft, "here is Neb turning up his nose at my gulf, just as I was thinking of presenting it to America!" "But, at any rate, is the water deep enough?" asked the engineer, "for a depth sufficient for the keel of the _Bonadventure_, would not be enough for those of our iron-clads." "That is easily found out," replied Pencroft. And the sailor sounded with a long cord, which served him as a lead-line, and to which was fastened a lump of iron. This cord measured nearly fifty fathoms, and its entire length was unrolled without finding any bottom. "There," exclaimed Pencroft, "our iron-clads can come here after all! They would not run aground!" "Indeed," said Gideon Spilett, "this gulf is a regular abyss; but, taking into consideration the volcanic origin of the island, it is not astonishing that the sea should offer similar depressions." "One would say too," observed Herbert, "that these cliffs were perfectly perpendicular; and I believe that at their foot, even with a line five or six times longer, Pencroft would not find the bottom." "That is all very well," then said the reporter; "but I must point out to Pencroft that his harbour is wanting in one very important respect!" "And what is that, Mr. Spilett?" "An opening, a cutting of some sort, to give access to the interior of the island. I do not see a spot on which we could land." And, in fact, the steep lava cliffs did not afford a single place suitable for landing. They formed an insuperable barrier, recalling, but with more wildness, the fiords of Norway. The _Bonadventure_, coasting as close as possible along the cliffs, did not discover even a projection which would allow the passengers to leave the deck. Pencroft consoled himself by saying that with the help of a mine they could soon open out the cliff when that was necessary, and then, as there was evidently nothing to be done in the gulf, he steered his vessel towards the strait and passed out at about two o'clock in the afternoon. "Ah!" said Neb, uttering a sigh of satisfaction. One might really say that the honest negro did not feel at his ease in those enormous jaws. The distance from Mandible Cape to the mouth of the Mercy was not more than eight miles. The head of the _Bonadventure_ was put towards Granite House, and a fair wind filling her sails, she ran rapidly along the coast. To the enormous lava rocks succeeded soon those capricious sand dunes, among which the engineer had been so singularly recovered, and which sea-birds frequented in thousands. About four o'clock, Pencroft, leaving the point of the islet on his left, entered the channel which separated it from the coast, and at five o'clock the anchor of the _Bonadventure_ was buried in the sand at the mouth of the Mercy. The colonists had been absent three days from their dwelling. Ayrton was waiting for them on the beach, and Jup came joyously to meet them, giving vent to deep grunts of satisfaction.