our had
passed away, he began to wish for the return of the doctor and the men,
but there was no rustle of leaves, no sound of breaking strand or twig,
everything was perfectly still, and the lad shifted his position a
little so as to find a place to rest his back, and as he did so a
peculiar sensation came over him. It was as if a mental shadow crossed
his mind, begetting a shock of dread. The next moment a heavy blow from
behind fell upon his head, and all was blank.

CHAPTER TWENTY NINE.

THE MISSING PAIR.

"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.

The consequence was that first one mark was found, then another, in the
shape of a broken twig or crushed-down patch of grass, but the next
minute the steps were lost, and everything looked so different in
descent they in a short time found themselves ready to give up the
laborious task of trying to follow in the steps taken when going up, and
glad to go back wherever the way was easiest.

To make up for this the little party sp