great precaution, in order to avoid
the weight of falling waters, which would cause the raft to founder in
an instant. Hans, however, steers admirably, and brings us to the other
extremity of the island.

I was the first to leap on the rock. My uncle followed, while the
eider-duck hunter remained still, like a man above any childish sources
of astonishment. We were now walking on granite mixed with siliceous
sandstone; the soil shivered under our feet like the sides of boilers in
which over-heated steam is forcibly confined. It is burning. We soon
came in sight of the little central basin from which rose the geyser. I
plunged a thermometer into the water which ran bubbling from the centre,
and it marked a heat of a hundred and sixty-three degrees!

This water, therefore, came from some place where the heat was intense.
This was singularly in contradiction with the theories of Professor
Hardwigg. I could not help telling him my opinion on the subject.

"Well," said he sharply, "and what does this prove against my doctrine?"

"Nothing," replied I dryly, seeing that I was running my head against a
foregone conclusion.

Nevertheless, I am compelled to confess that until now we have been most
remarkably fortunate, and that this voyage is being accomplished in most
favorable conditions of temperature; but it appears evident, in fact,
certain, that we shall sooner or later arrive at one of those regions
where the central heat will reach its utmost limits, and will go far
beyond all the possible gradations of thermometers.

Visions of the Hades of the ancients, believed to be in the centre of
the earth, floated through my imagination.

We shall, however, see what we shall see. That is the Professor's
favorite phrase now. Having christened the volcanic island by the name
of his nephew, the leader of the expedition turned away and gave the
signal for embarkation.

I stood still, however, for some minutes, gazing upon the magnificent
geyser. I soon was able to perceive that the upward tendency of the
water was irregular; now it diminished in intensity, and then, suddenly,
it regained new vigor, which I attributed to the variation of the
pressure of the accumulated vapors in its reservoir.

At last we took our departure, going carefully round the projecting, and
rather dangerous, rocks of the southern side. Hans had taken advantage
of this brief halt to repair the raft.

Before we took our final departure from the island