"Strange," muttered the captain uneasily. "It isn't like Ruth to go off to any distance without telling me about it beforehand." "Nor Allen neither," put in Tyke loyally. "You might almost think the earth had swallowed them up," pursued the captain, little thinking how near he was to guessing the truth. "Well, the only thing to do is to keep looking for 'em until we find 'em," said Tyke. "You take that side of the hill, Rufe, and I'll take the other. We'll come across them probably before we meet up with each other." The two men separated on their quest, calling out at frequent intervals. It did not take them long to skirt the base of the whale's hump, but when at last they met each saw only disappointment and a growing alarm in the eyes of the other. "We'll have to try it again and make a wider circle," exclaimed Hamilton desperately. "We've simply got to come across them somewhere around here." "Of course we shall," said Tyke heartily, though the crease in his forehead belied the confidence of his words. Once more they made the round of the hump, this time ranging out much further from the base. Still their efforts were fruitless, and when they met once more, neither tried to disguise from the other the growing panic in his heart. "Ruth, Ruth!" groaned the captain. "Come now, Rufe, brace up," comforted Tyke. "While there's life there's hope." "That's just it," replied the captain. "But how do we know there is life? Something serious must have happened to them, or they'd never stay away like this. They'd know we'd be worried about them after that shock came and they couldn't have come back to us quick enough, if they'd been able to come." Tyke could not deny the force of this. "Well now, Rufe, let's get down to the bottom of this," he said. "I'm afraid just as you be that they're in trouble of some kind. Now what could make trouble for them on this island? There ain't any wild beasts of any account here, do you think?" "Not that I ever heard of," replied the captain. "We're too far south for mountain lions and too far north for jaguars. There may be an occasional wildcat, but it wouldn't be likely to attack a single person let alone two together. There may be snakes here though for all I know." "Nothing doing there," said Tyke decisively. "Mebbe there's boas, but if so there're a mild and harmless kind, such as those they make household pets of in some places to keep away the rats. And if there are any poisonous snakes, it's against all likehood that both Ruth and Allen would be bitten. One of them would come scurrying to us at once for help for the other. "Besides," he went on, "I know that Allen had his revolver along with him and he's a sure shot. No, I don't think we have to worry about animals or snakes." "What is there left then?" groaned the captain.