It was a new role for Mark--to be cheerful in the face of difficulties
--and Jack appreciated it. They stretched out on the hard, rocky floor
of the cavern, taking care to fix their life-torches so that the fumes
would dispel the poisonous gases. Then the two lads joined Andy in
slumberland.

Meanwhile, as may be imagined, those aboard the projectile were very
anxious about the fate of the two boys and the hunter. They could not
understand what delayed them, and, though they guessed the real cause,
after several hours had passed, there was nothing the two scientists
could do.

They could not move the projectile until it had been repaired, and this
could not be done, without the tool--at least, they did not believe so
then. Nor did Mr. Henderson and the German think it would be safe to
start out in search of the wanderers.

"For," said Mr. Henderson, "if we went we would easily get lost amid
these peaks ourselves, and they are so much alike and in such numbers
that there is no distinguishing feature about them. We had better stay
here in charge of the _Annihilator_ until the boys and Andy come back.
They can't be away much longer now."

So worn out and exhausted were the boys and the hunter that they slept
for several hours in the cave, and the rest did them good. They awoke
in better spirits, and, after a frugal meal and a sip of the fast-
dwindling water, they started off once more to locate the projectile.

"I'm a regular amateur hunter to go and lose my compass," complained