For about twenty yards away the handle of the boat-hook suddenly shot above the surface, and floated, bobbing gently up and down like a huge quill float, the metal on the end weighting it sufficiently to keep it nearly upright. A touch or two with the oars sent the dinghy within reach, and the boat-hook was recovered, but with its gun-metal head a good deal bent. "Got a good strong skull," said the captain, holding the end for Jack to see. "Look under the canoe now." Jack glanced over the side, and there was not a shark to be seen as the agitated water grew calm again; but even as he looked, first one and then another shadowy object reappeared, until five had resumed their places, waiting for the dead that might float out of the canoe, but in this case waiting in vain. "The horrible wretches!" said Jack. "It's their nature, sir. They are the scavengers of the sea in their way, just as the crocodiles are of the great rivers.--Row back, Lenny.-- There is your father on the deck." "And Doctor Instow too," said Jack. "Here, I say," cried the doctor, "play fair. Don't have all the adventures to yourselves. Been harpooning fish? Ugh!" he continued. "Sharks. I should like a turn at them." Over the breakfast the position was discussed. "Well, you saw, Sir John, we would be obliged to camp out for one, perhaps two nights, if we tried to row inside the reef, and it would be dangerous with the enemy about." "And the steam is up, and we could run round outside the reef, and be back here in the evening." "Why not try inside?" said the doctor. "I was thinking of it," replied the captain. "There is the risk of coming upon shallow water; but if Sir John likes we'll try. I can have a couple of men sounding." "It would be much more interesting than going out to sea," put in Jack. "It's so much better than having to be always looking through a glass." "Try inside, Bradleigh," said Sir John. "It means coals, sir." "Never mind that," said Sir John, who had just drawn a deep breath full of satisfaction to see the intense interest his son was taking in everything now. "And what about our friends the blacks?" said the doctor. "Well, sir, we should find out whether they are neighbours or visitors from some other island. I expect the latter," said the captain, "but I want to know." "Wouldn't there be time to try for the sharks first?" said Jack. "Oh yes, we could give an hour to that," said the captain; "for perhaps while we are rounding the island our friends of last night will come and fetch their boat. They are welcome to it, I suppose, Sir John. You don't want to take it back to England as a specimen?" "No," said Sir John, smiling, "let them have it; and I hope we shall see no more of them while we are here."