knows it, or who has the means wherewith to accomplish it. And
I certainly won't tell!"

The worried expression on Parkinson's face increased in intensity.
There was something in the Venerian's voice that convinced him that he
meant what he said.

Then suddenly his countenance cleared, and a happy smile replaced his
frown.

"Perhaps you won't tell, but I think you will. There are more ways
than one of forcing you."

* * * * *

Parkinson had hit upon a solution to his problem. The Venerians had
reproduced his knowledge in their brains; why wouldn't it be possible
for him to reverse the operation?

In a moment he secured the thought-transference apparatus from a case
in the rear of the room, and bore it to the chair, and in spite of the
Venerian leader's struggles, placed it upon his head. He put the
head-phones over his own ears, and began fumbling with the controls.

Suddenly he seemed to strike the right combination. There was a faint,
humming drone in his ears; after a moment this was replaced by a loud
crackling--and the knowledge of the man from Venus was becoming his
own.

Somewhat dazed, Parkinson shut off the current. His mind was in a
turmoil. He was in possession of knowledge of such an amazing
character that, for the moment he had lost his mental equilibrium.
Indeed, so strange was his new-found knowledge, that he could not
grasp the significance of even half of the facts in his mind.

But already, he knew how, with animal electricity, they had paralyzed
him; knew what had happened to him on the operating table; knew the
nature of the dread disease that destroyed his arm; the Gray
Plague--and knew the cure!

A sudden thought arrested this review of his new knowledge. The Gray
Plague! At that very moment incalculable quantities of the deadly
bacilli were being cast into the air. And he was doing nothing about
it!

He glanced at the Venerian. He was still unconscious, and would remain
so for some minutes to come. And even if he did recover his senses, he
was securely fastened to the chair; Parkinson dashed out of the room,
crossed to the sphere, and passed through the open doorway.

Without hesitation he manipulated the controls, directed by his
Venerian knowledge. Rapidly the sphere rose to the surface.

As it came to rest on the floor of the tower, Parkinson sprang from
the car, and headed toward a mass of intricate machinery that filled
fully a quarter of the