hat an hour or two's sleep would give
me the strength I needed to renew with a will, and more chance of
success, my efforts to escape.

Light was too precious to waste, so I blew out my lantern, and, curling
up on the sand, almost instantly fell asleep. But, before I lapsed into
unconsciousness, I had clutched hold of one sustaining thought in the
darkness--the assurance of Calypso's safety, so confidently announced by
her father: "Don't be afraid for her. I know my daughter." Whatever
happened to me, she would come out all right. As her brave shape flashed
before my mind's eye, down there under the earth, I could have no doubt
of that.

CHAPTER XV

_In Which I Pursue My Studies as a Troglodyte._

My instinct had been right in giving way to my drowsiness, for I woke up
from my sleep a new man. How long I had been there, of course, I had no
means of knowing; but I fancy I must have slept a good while, for I felt
so refreshed and full of determination to tackle my escape in good
earnest.

It is remarkable how rest sharpens one's perceptions. When we are weary,
we only half see what we look at, and the very thing we are desperately
seeking may be right under our nose and we quite unaware.

So I had hardly relit my lantern, when its rays revealed something which
it seemed impossible for any one with eyes, however weary, to have
overlooked.

In the right-hand corner of the little cavern, five or six feet above my
head, was a dark hole, like the entrance to a tunnel, or, more properly
speaking, a good-sized burrow--for it was scarcely more than a yard in
diameter. It seemed to be something more than a mere cavity in the rock,
for, when I flashed my lantern up to it, I could see no end. To climb
up to it, at first, seemed difficult; but providentially, I had a stout
claspknife in my pocket, and with this I cut a step or two in the porous
rock, and so managed it. Lying flat on my stomach, I looked in.

It was, as I had thought, a narrow natural tunnel, snaking through the
rocks--as often happens in those curious fantastic coral formations--for
all the world, indeed, as if it had been made ages ago by some monstrous
primeval serpent, a giant worm-hole no less, leading--Heaven alone knew
where.

There was just room to crawl along it on all fours, so I started
cautiously, making sure I had my precious matches, and my jackknife all
safe.

After all, I said to myself, I was no worse off than thousands of poor
d