“Here! Hi! Jack! Where are you, lad?” There was no reply, and the doctor called the nearest of the men, who were slowly making their way through the dense growth, putting up some strange bird from time to time.

“Where’s Mr Jack, Lenny?”

“Mr Jack, sir? Arn’t seen him lately. ’Long o’ Ned, I think. See Mr Jack from where you are, mate?”

“No,” came back, and the fresh speaker hailed his nearest companion, and he his. But no one had seen the boy lately. They had all been too much occupied in looking out for rare birds.

“Let’s wait a bit,” said the doctor. “Give them time to come up. Here, Lenny—and you—let’s look at the sport.”

He sat down on a block of lava, and became so interested in the specimens he had obtained that he did not notice the lapse of time.

“Here,” he cried at last, “they must have knocked up, and are waiting for us to go back. Why, we must have come much farther than ever we came before.”

“That’s why we’ve got such good birds, sir,” said Lenny.

“Perhaps so. Well, back again now.—Oughtn’t to have left him behind like that,” muttered the doctor to himself.

He was hot and weary from his exertions, but his anxiety made him hurry back nearly in the path they had made in ascending, but that soon proved to be too difficult, the growth having sprung back after they had passed, and as they had gone up the steep slope well separated, the tracks were feebly marked, and not as they would have been had they followed in each other’s steps.