hich a strong man might climb,
led them down and still down....

But, as to the rest--Gor's promise of safe return to the light of day
and that outer world where the Sun-god shone--how was Gor to know that
a mighty glacier would lock the whole land in ice for endless years,
and, retreating, leave their upper caves filled and buried under a
valley heaped with granite rocks?

Even had the way been open to the land above, Gor himself could never
have known when that ice-sheet left. For when that day came and once
more the Sun-god drew steamy spirals from the drenched and thawing
ground, Gor, deep down in the earth, had been dead for countless
years. Only the remote descendants of that earlier tribe now lived in
their subterranean home, though even with them there were some who
spoke at times of those legends of another world which their ancestors
had left.

And through the long centuries, while evolution worked its slow
changes, they knew nothing of the vanishing ice, of the sun and the
gushing waters, the grass and forests that came to cover the earth.
Nor did their descendants, exploring interminable caves, learning to
tame the internal fires, always evolving, always growing, have any
remote conception of a people who sailed strange seas to find new
lands and live and multiply and build up a country of sky-reaching
cities and peaceful farmlands, of sunlit valleys and hills.

But always there were adventurous souls who made their way deeper and
deeper into the earth; and among them in every generation was one
named Gor who was taught the tribal legends and who led the
adventurers on. But legends have a trick of changing, and instead of
searching upward, it was through the deeper strata that they made
their slow way in their search for a mystic god and the land of their
fathers' fathers....

CHAPTER I

_A Man Named Smith_

Heat! Heat of a white-hot sun only two hours old. Heat of blazing
sands where shimmering, gassy waves made the sparse sagebrush seem
about to burst into flames. Heat of a wind that might have come out of
the fire-box of a Mogul on an upgrade pull.

A highway twisted among black masses of outcropping lava rock or
tightened into a straightaway for miles across the desert that swept
up to the mountain's base. The asphalt surface of the pavement was
almost liquid; it clung stickily to the tires of a big car, letting go
with a continuous, ripping sound.

Behind the wheel of the weatherbea