Tim's sudden laughter was almost hysterically triumphant. "I mean that
this is one time a 'groundhog engineer' knows more than a spaceman.
There's no time to explain now, but quick!--you have some gun-capsules,
haven't you?"
"Y-yes, but--"
"Give them to me! All you have. And hurry!"
* * * * *
As he spoke, he was emptying his own capacious ammunition pouch.
Capsule after capsule poured from it, until he had an overflowing
double handful. With frenzied haste he broke the safety-tip off the
first, tossed the cartridge into the stream that ran through their
prison. As it struck, it hissed faintly; bubbles began to rise from the
fluid, and a thin, steamy film of vapor rose whitely.
"Do that to all of them. Toss them in there! I'm right! I know I am. I
_have_ to be!"
Bewilderedly, Captain Lane and Dorothy began doing as he ordered. A
dozen, a score, twoscore of the heat-gun cartridges were untipped,
thrown into the coursing stream. The white film became a cloud, a fog,
a thick, dense blanket about them, through which they could barely see
each other. And still Tim's voice cried, "More! Faster! All of them!"
Then the last capsule had been tossed into the fluid, and their only
contact with each other was by speech and the sense of touch. They
were engulfed in rolling billows of white; vapor that frosted their
view-panes, screened the world from view.
For half an hour they stood there waiting, turn with a thousand mingled
doubts. Until, at last--
"I can't stand it any longer, Tim!" cried Dorothy. "What is it? What do
we do? What is this wild plan?"
The vapor had thinned a trifle. And through gray mists, she saw a form
loom before her. It was Tim's shape, and his hand stretched out to her.
His voice was tense.
"Now--" he said. "Now we walk from our prison!"
And he flung open the door.
"Careful!" cried Captain Lane. "The guards, son! 'Ware the Harpy
guards!"
But no guards sprang forward to bar their passage. There were guards, a
dozen of them. But not a single one of them moved.
And Dorothy, wiping a sudden veil of hoar-frost from her view-pane, saw
them and gasped.
"Dead!" she cried. "Tim--they're all dead!"
Tim shook his head.
"Not dead, darling. Just--sleeping! And now let's hurry. Before they
waken again!"
* * * * *
When they had reached the uppermost corridor of the caverns, they
paused for a moment's rest. It was then that Captain Lane found time
for the question that had plagued him.
"You were right, Tim. They were sleeping. I could see that overlord's
nose-leaf quivering with slow breath just before I shot him. But--but
what caused it? Anesthetic? I don't understand."
"No," grinned Tim, "it was not an anesthetic. It was a simple matter of
remembering a biological trait of bats, and applying a little technical
knowledge. The knowledge--" He could not resist the dig. "The special
knowledge of what you called a 'hot-and-cold' expert. Refrigeration!
"Bats are hibernating creatures. And hibernation is not merely a matter
of custom, tradition, desire to sleep--it is a physical reflex which
cannot be avoided when the conditions are made suitable.
"Bats, like many other hibernating mammals, are automatically forced
into slumber when the temperature drops below 46°F. Knowing this,
and realizing that was the reason the Harpies--bat-like in form
and habit--kept their underground chambers superheated I applied an
elemental principle of refrigeration to cool their city below that
point!"