nelessly. "This means we are--"

Diane had overheard. Harkness' pause had come too late.

"Yes?" she encouraged. "This means we are entombed?--buried here? Is
that it?"

Her voice was quiet; her eyes, in the light of the little flash, were
steady in their look upon the man who was leader of the expedition.
Diane Vernier might shudder with horror before some obscene beast--she
would tremble with delight, too, at sight of some sudden beauty--but
she was not one to give way to hysteria when a situation must be
faced. No despair could be long-lived under the spell of those eyes,
brave and encouraging.

"No," said Walter Harkness: "we will find some way to escape. This is
blocked. We will follow the cave back and see where it leads. There
must be other outlets. We're not quitting now." He smiled with a
cheerful confidence that gave no hint of being assumed, and he led the
way with a firm step.

* * * * *

Diane followed as usual, close to Chet. But her eyes were upon their
leader; they would have repaid him for a backward look.

To a mineralogist this tunnel that nature had pierced through the rock
would have been an endless delight, but to a man seeking escape from
his living tomb it brought no such ecstasy. The steady, appraising
glance of Harkness was everywhere--darting ahead, examining the walls,
seeking some indication, some familiar geological structure, that
might be of help.

He stopped once to kick contemptuously at a vein of quartz. Three feet
in thickness--and it crumbled to fragments under his foot to release a
network of gold.

"Rotten with it," he said.

And the only comment came from Chet: "A fat lot of good it does us!"
he replied.

The cavern branched and branched again; it opened to a great room
higher than their light could reach; it narrowed to leave apertures
through which they crawled like moles; it became a labyrinth of
passages from which there seemed no escape. Each turn, each new
opening, large or small--it was always the same: Harkness praying
inaudibly for a glimpse of light that would mean day; and,
instead--darkness!--and their own pencil of light so feeble against
the gloom ahead....

CHAPTER VIII

_The Half-Men_

"The Valley of the Fires," Harkness was to call it later, and shorten
it again to "Fire Valley." The misty smokes of a thousand fires rose
skyward from the lava beds of its upper end.

Where the lava flow had stopped and the lowe