projectile.

"When that is snapped over, it makes the contact that sets the
magnetizing mechanism into action," she explained. "Then the
projectile will go hurtling directly for the source of any radio waves
within range. I don't know the nature of its mechanism. Uncle merely
told me that it is the application of an entirely new principle of
electricity."

Dixon laid the long projectile down on the work-bench, and began
packing his lead cylinder of explosive inside it. He had to release
the lead cylinder's safety catch before closing the projectile, which
made his work a thrillingly precarious one, for any sharp blow now
would detonate the unstable mixture of gas and radium compound in one
cataclysmic explosion.

He sighed in relief as he finally straightened up with the completed
projectile held carefully in both hands.

"All we have to do now, Ruth," he said, "is step out from under this
roof and snap that energizing stud. Then this little package of
destruction will be on its way to our Centaurian friends up there by
that pestilential green moon."

* * * * *

Ruth stepped ahead to open the door for him. With the end of their
task so near at hand, both forgot to be cautious.

Ruth threw the door open and took one step outside, then suddenly
screamed in terror as her shoulders were encircled by a long
snake-like object that came whipping down from some vast something
that had been lurking just outside. Dixon tried to dodge back, but too
late. Another great hairy tentacle came lashing around his shoulders,
pinning his arms tightly and jerking him out of the doorway.

He had a swift vague glimpse of a hybrid looming there in the green
moonlight--a tarantula hybrid that in size and horror dwarfed any of
the frightful products of Centaurian science that he had yet seen.

Before Dixon had time to note any of the details of his assailant
another tentacle curled around him, tearing the projectile from his
grasp. Then he was irresistibly drawn up toward that grisly head where
Ruth's body was also suspended in one of the powerful tentacles. The
next moment, bearing its burdens with amazing ease, the giant hybrid
started off.

Dixon tried with all his strength to squirm free enough to get a hand
upon the revolver in his pocket, but the constricting tentacle did not
give for even an inch. The only result of his effort was to twist his
hood to one side, leaving him as effectually blindf