But in a little while a danger developed which we had not thought of. It
arose from the existence of other caverns whose mouths opened upon the
plain. To have precipitated the sleds into these would have been fatal.
Luckily, shafts of light issued from all of them, and warned by these, we
managed to avoid the danger. But it was not entirely passed before we had
traveled at least a hundred miles. It was like an immense city of prairie
dogs without mounds. The cavern that we had discovered on our arrival was
evidently situated on the outskirts of the group, and now we were passing
through the center of it. Occasionally we saw a huge white form disappear
in one of the holes as we swiftly approached, but that was all we beheld
of the inhabitants. But the spectacle of the shafts of light rising all
around us was amazing. When we were in the midst of it Edmund hesitated
for a moment, muttering that we had been too hasty and should have
remained longer to study the peculiarities of this wonderful world of
night; but finally he decided to keep on, and soon afterwards we saw the
last of the caverns. Then, as there appeared to be no obstructions of any
kind, the speed was worked up to a hundred miles an hour. Going straight
ahead as we did, there was no danger of the sleds being overturned.

Having, as Edmund had calculated, about five thousand miles to go before
reaching the edge of the sun-illuminated hemisphere, it was evident that,
at our present rate of progress, we should arrive there in a little over
two days by the calendar clock. We guided our course by the stars, and
for me one of the most interesting things was to see the earth sinking
toward the horizon, accompanied by the stars, as if the heavens were
revolving in a direction opposed to our line of travel. We smoked and
talked and ate and slept in the old way, while the marvelous mouths in
the wall resumed their strange deglutition. Thus the time passed, without
ennui, until, unexpectedly, a new phenomenon captured our attention.