"But on Wonder Island we had several methods of talking to each other," remarked Uraso. "For instance, we would perfectly imitate the cries of a number of birds, and also of certain animals, and of the wood insects. Thus, a nightingale would mean watchfulness; the chirrup of a cricket would be the signal that the enemy was not dangerous, or that there were not many of them; the cry of the Lost Soul bird would indicate that there was great danger, and so on with the birds and animals that make noises."
"But I have discovered another thing," remarked Muro.
"And what is that?" said John.
"The natives here are cannibals."
"That merely confirms my knowledge of the matter," said John.
The boys looked at John in amazement. How did John know there were cannibals on the island?
"When did you learn that?" asked Harry.
"Yesterday," was his reply.
"What did you find that makes you believe that?"
"I discovered a bone which was once part of a human body."