On this occasion Pencroft and his companions, who were occupied with loosing themselves, received unexpected aid from the prisoner, who emerged from the hatchway as if his sailor's instinct had suddenly returned, broke a piece out of the bulwarks with a spar so as to let the water which filled the deck escape. Then the vessel being clear, he descended to his cabin without having uttered a word. Pencroft, Gideon Spilett, and Herbert, greatly astonished, let him proceed. Their situation was truly serious, and the sailor had reason to fear that he was lost on the wide sea without any possibility of recovering his course. The night was dark and cold. However, about eleven o'clock, the wind fell, the sea went down, and the speed of the vessel, as she laboured less, greatly increased. Neither Pencroft, Spilett, nor Herbert thought of taking an hour's sleep. They kept a sharp look-out, for either Lincoln Island could not be far distant and would be sighted at daybreak, or the _Bonadventure_, carried away by currents, had drifted so much that it would be impossible to rectify her course. Pencroft, uneasy to the last degree, yet did not despair, for he had a gallant heart, and grasping the tiller he anxiously endeavoured to pierce the darkness which surrounded them. About two o'clock in the morning he started forward,-- "A light! a light!" he shouted. Indeed, a bright light appeared twenty miles to the north-east. Lincoln Island was there, and this fire, evidently lighted by Cyrus Harding, showed them the course to be followed. Pencroft, who was bearing too much to the north, altered his course and steered towards the fire, which burned brightly above the horizon like a star of the first magnitude. [Illustration: A LIGHT! A LIGHT!] CHAPTER XV The Return -- Discussion -- Cyrus Harding and the Stranger -- Port Balloon -- The Engineer's Devotion -- A touching Incident -- Tears flow. The next day, the 20th of October, at seven o'clock in the morning, after a voyage of four days, the _Bonadventure_ gently glided up to the beach at the mouth of the Mercy. Cyrus Harding and Neb, who had become very uneasy at the bad weather and the prolonged absence of their companions, had climbed at daybreak to the plateau of Prospect Heights, and they had at last caught sight of the vessel which had been so long in returning. "God be praised! there they are!" exclaimed Cyrus Harding. As to Neb in his joy, he began to dance, to twirl round, clapping his hands and shouting, "Oh! my master!" A more touching pantomime than the finest discourse. The engineer's first idea, on counting the people on the deck of the _Bonadventure_, was that Pencroft had not found the castaway of Tabor Island, or at any rate that the unfortunate man had refused to leave his island and change one prison for another. Indeed Pencroft, Gideon Spilett, and Herbert were alone on the deck of the _Bonadventure_.