None came, and they hurried on, rarely recognising anything to act as a guide, but steadily going down toward the shore; and as there was no reply to his calls, the doctor soon came to the conclusion that, tired of waiting, Jack had turned back, and in the full expectation of finding the missing ones down by the boat, the party was pressed on, but with their leader getting more annoyed at every step. The boat was invisible till they were close upon it, lying in the mouth of the little river where the great trees spread their boughs right across, and at the first rustle of the bushes being heard the sailors in charge started up and began to draw her close in shore. The doctor uttered an ejaculation full of annoyance, but began clinging directly after to the thought which struck him. "How long have they gone on board?" he cried as soon as he was well within hearing. Then his hopes were crushed, for the men addressed replied-- "Gone on board, sir? Who gone on board?" "Mr Jack and his man." "Haven't been down here, sir. Arn't lost 'em, have you?" The doctor made no reply. "Here," he cried, "take these birds, and you two who have been resting come back with me. Lenny, I want you, and you come too," he continued to another of the men. The other two who had come down from the mountain slope were eager to return, but the doctor ordered them to take charge of the boat, and without pausing a minute shouldered his gun and turned to follow the path they had taken that morning, with better hope of success. "I dare say we came close by them somewhere," he said to Lenny. "I hardly see though how we could have missed them." "Strikes me, sir, as I know how it was," said the man. "You think you know?" "Yes, sir, but it's only thinking, and mayn't be right." "Tell me what you think," cried the doctor impatiently. "It was hot, sir, steamy hot under the trees, and Mr Jack is young and none too strong, and Ned arn't quite got over his trouble." "Yes, of course. Well, go on." "Well, sir, they must have trudged after us till they were tired out, and then sat down to wait for us, and went to sleep." "I hope that's it, Lenny," said the doctor as they struggled on, up and up, amongst tree, bush, and rock, while, to add to their difficulty, a complete change came on with tropic rapidity, a black curtain of clouds swept across the sky, and in an incredibly short time the lightning flickered for a few minutes through the trees, and then came in blinding flashes, accompanied more than followed by peal upon peal of thunder which seemed to shake the island to its foundation.