*

Down the ropes swarmed the gang of negroes. Dr. Bird indicated an area
at one end of the cavern and directed them to dig. The blacks flew to
work with a will. The top soil and subsoil were rapidly tossed into
buckets and hauled to the surface. When bare rock lay before them, the
negroes ceased their efforts.

"What next, Doctuh, suh?" asked the foreman.

"Get dynamite!" cried the doctor. "If I'm right, this underground
cavern is entered by a tunnel. We'll blast away this caved-in rock
until we locate it."

Then occurred a strange thing.

"There is no need to go to that trouble, Dr. Bird," spoke a metallic
voice, from nowhere, it seemed. The negroes looked at one another.
Picks and shovels fell from nerveless hands.

"Your guess about a tunnel is correct, Doctor," went on the Voice.
"There is a tunnel leading away from the spot where you are, but to
find the end would be useless to you. I have prepared for that."

From the blacks came a low moan of fear.

"Ha'nts!" cried one of them. The cry was taken up and spread into a
rolling chorus of fear. With one accord they dropped their tools and
stampeded in a mad rush toward the dangling ropes. Carnes sprang
forward to stop them.

"Let them go, Carnes!" cried the doctor. "Their work is done for the
present. Let's locate that radio receiver."

"That also will be a useless search. Doctor," spoke up the Voice
again. "I have perfected a transmitter which will send my voice
through space and make it audible without the aid of the clumsy
apparatus you depend on. I am also able to see you through the miles
of intervening rock without the aid of any instruments at your end."

* * * * *

"I presume that you can hear me as well?"

"Certainly, Doctor. To save you trouble--and I dislike to see you
waste the efforts of your really good brain on minor problems--I will
tell you that your surmise is correct. A tunnel does lead both to and
from the place where you stand. It twists and turns so that even you
would be puzzled to plot a general direction. You would have to follow
it inch by inch. If you tried that, naturally I would cause it to
collapse before you, or on top of you, if you got too close. Be
content with what you have seen and seek a better way to trace me."

"Who are you, anyway?" blurted out Carnes.

"Is it possible that you do not know? Such is fame. I thought that at
least my friend Mr. Carnes would suspect that Ivan S