own down by
workmen.

"This is where they take out the temite ore, I imagine," said
Kincaide, picking up a loose fragment of rock. He pointed to a smudge
of soft, crumbly gray metal, greasy in appearance, showing on the
surface of the specimen he had picked up. "That's the stuff, sir,
that's causing us all this trouble: nearly pure metallic temite." He
dropped the fragment, looking about curiously. "But where," he added,
"are the miners?"

"I'm inclined to believe we'll find out before we get back to the
_Ertak_," said Correy grimly. "Everything's moved along too sweetly;
trouble's just piling up somewhere."

"That remains to be seen," I commented. "Let's move on, and see what's
beyond. That looks like a door of some sort, on the far side. Perhaps
it will lead us to something more interesting."

"I hope it does," growled Correy. "This underground business is
getting on my nerves!"

It was a door I had seen, a huge slab of light yellow-green metal. I
paused, my hand on the simple latch.

"Stand to one side," I said softly. "Let's see what happens."

I lifted the latch, and the heavy door opened inward. Cautiously, I
stared through the portal. Inside was blackness and silence;
somewhere, in the far distance, I could see two or three tiny
pin-pricks of green light.

"We'll take a look around, anyway," I said. "Follow me carefully and
be ready for action. It seems all right, but somehow, I don't like the
looks of things."

In single file, we passed beyond the massive door, the light from the
large room outside streaming ahead of us, our shadows long and
grotesque, moving on the rocky floor ahead of us.

Then, suddenly, I became aware that the path of light ahead of us was
narrowing. I turned swiftly; the door must be closing!

As I turned, lights roared up all around us, intense light which
struck at our eyes with almost tangible force. A great shout rose,
echoing, to a vaulted ceiling. Before we could move or cry out, a
score of men on either side had pinioned us.

"Damnation!" roared Correy. "If I only had the use of my fists--just
for a second!"

* * * * *

We were in a great cavern, the largest I have ever beheld. A huge
bubble, blown in the molten rock by powerful gases from the seething
interior of the world.

The roof was invisible above our heads, and the floor sloped down
gently in every direction, toward a central dais, so far away that its
details were lost to