"What on earth caused the explosion?"

"A trickle of water into the pit. Where it came from----"

"That was the sign!" exclaimed Forrester aloud, knowing that the priest could not understand him. But Wing Wu understood.

"What sign, sir?" he asked eagerly.

"Shall we tell him?" said Beresford.

Forrester hesitated for a moment.

"Not yet," he answered.

Wing Wu sighed, and turned away.

The priest at the entrance was joined by a second, drawn by the noise from the guard-room beyond the lake. They talked together for a few minutes, then the second man departed.

"He will tell the Old Man, no doubt," said Forrester to his companion.