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 

 Prev. P 19/21 next