“See what?” cried the mate.

“The flag, Mr Gregory. Look!” cried Mark.

For plainly enough now a signal was being made from one of the stern windows of the ship, and as far as they could make out it was a white cloth being waved to and fro.

“Now if we could only answer that,” said the major, “it would encourage them.”

“I could answer it, sir,” cried Mark.

“How, my lad?”

“Give me a big handkerchief, and I’ll climb up that tree and tie it to one of those branches.”

“Capital, my lad,” said the major. “But, no; risky.”

“They could not hit me, sir,” cried Mark; “and it’s like taking no notice of my father’s signals to do nothing.”

“I think he might risk it, major,” said Gregory.