--and no way through!"

And then Holmes came to it. It barred the passage, and was apparently
unbroken. Yet the draft still came!

"Search for where the draft enters!" he yelled. "You take that side!"
And he started feeling over the clammy, uneven surface, searching
frantically for a cleft. It seemed to be hopeless. Quade stood staring
back into the gloom, his eyes looking for what he knew was surging
towards them. His face had gone sickly white, he was trembling as if
with fever, and he sucked in air with long, racking gasps.

"Here! I have it!" cried the girl suddenly at her end of the wall. The
other three ran over, and saw, just above her head, a narrow rift in
the rock, barely wide enough to squirm through. "Into it!" Phil
ordered tersely. He grasped her, raised her high, and she wormed
through. Quade scrambled to get in next, but Holmes shoved him aside
and boosted the old man through. Then he helped the other.

A second after he had swung himself up, a wave of whitish matter
rolled up below, hungry pseudopods reaching for the food it knew was
near. It began to trickle up the wall....

* * * * *

The crack was narrow and jagged; utterly black. Phil could hear Quade
frantically worming himself ahead, and he wondered achingly if it
would lead anywhere. Then a faint, clear voice from ahead rang out:

"It's opening up!"

Sue's voice! Phil breathed more easily. The next moment Quade
scrambled through; dim light came; and they were in another vast,
ghostly-lit cavern.

The crack came out on its floor-level; Guinness was resting near, and
his daughter had her hands on a large boulder of rock. "Let's shove it
against the hole!" she suggested to Phil. "It might stop it!"

"Good, Sue, good!" he exclaimed, and at once all four of them strained
at the chunk, putting forth every bit of strength they had. The
boulder stirred, rolled over, and thudded neatly in front of the
crack, almost completely sealing it. There was only a cleft of five
inches on one side.

But their expression of relief died in their throats. A tiny trickle
of white appeared through the niche. The amorphous monster was
compressing itself to a single stream, thin enough to squeeze through
even that narrow space.

They could not block it. They had nothing to attack it with. There was
nothing to do but run.... And hope for a chance to double back....

As nearly as they could make out, this second cavern was as lar