* * * * *

Under another day's sun the hot asphalt was again taking the print of
the tires of Rawson's old car. But this time, when he came to the
almost obliterated marks that led through the sand toward distant
mountains, he stopped, partially deflated the tires to give them a
grip on the sand, and swung off.

"A fool, kid trick," he admitted to himself, "but I want to see the
place. I'll see plenty of it before I'm through, but right now I've
got to have a look; then I'll buckle down to work.

"Thermal Explorations, Limited!" The name rang triumphantly in his
mind. "A million things to do--men, crews for the drills, derricks....
We'll have to truck in over this road; I'll lay a plank road over the
sand. And water--we'll have to haul that, too, until we can sink a
well. We'll find water under there somewhere. I've got to see the
place...."

The black sides of the mountains were nearer: every outcropping rock
was plainly volcanic, and great sweeping slopes were beds of ash and
pumice; the wheel marks, where they showed at all, wound off and into
a canyon hidden in the tremendous hills that thrust themselves
abruptly from the desert floor.

The mountains themselves towered hugely at closer range, but the road
that Rawson followed climbed through them without traversing the
highest slopes. It was scarcely more than a trail, barely wide enough
for the car at times, but boulder-filled gullies showed where the
hands of men had worked to build it.

* * * * *

He came at last into the open where a shoulder of rock bent the road
outward above a sea of sand far below. And now the mountains showed
their circular arrangement--a great ring, twenty miles across. At one
side were three conical peaks, unmistakable craters, whose scarred
sides were smothered under ash and sand that had rained down from
their shattered tops in ages past. Yet, so hot they were, so clear-cut
the irregularly rimmed cups at their tops, that they seemed to have
pushed themselves up through the earth in that very instant. At their
bases were signs of human habitation--broken walls, scattered stone
buildings whose empty windows gaped blackly. This was all that
remained of New Rhyolite.

Rawson looked at the "ghost town" which had never failed to interest
him, but he gave no thought now to the hardy prospectors who had built
it or to the vein of gold that had failed them. His searching eyes
ca