the theory he had hardly dared
believe. The Eye of Allah--the maniac--was real; and his power for
evil! There was work to be done, and the point of beginning was not
plain.

How far did the invisible arm reach? How far could the Eye of Allah
see? Where was the generator--the origin of this wireless power; along
what channel did it flow? A ray of lightless light--an unseen ethereal
vibration.... Delamater could only guess at the answers.

The current to kill a man or to flash a spark into silken powder bags
need not be heavy, he knew. Five hundred--a thousand volts--if the
mysterious conductor carried it without resistance and without loss.
People had been killed by house-lighting currents--a mere 110
volts--when conditions were right. There would be no peculiar or
unusual demand upon the power company to point him toward the hidden
maniac.

He tossed restlessly throughout the night, and morning brought no
answer to his repeated questions. But it brought a hurry call from his
Chief.

"Right away," was the instruction; "don't lose a minute. Come to the
office."

He found the big man at his desk. He was quiet, unhurried, but the
operative knew at a glance the tense repression that was being
exercised--the iron control of nerves that demanded action and found
incompetence and helplessness instead.

"I don't believe your fantastic theories," he told Delamater.
"Impractical--impossible! But--" He handed the waiting man a paper.
"We must not leave a stone unturned."

Delamater said nothing; he looked at the paper in his hand. "To the
President of the United States," he read. "Prepare to meet your God.
Friday. The eighth. Twelve o'clock."

The signature he hardly saw; the staring, open eye was all too
familiar.

"That is to-morrow," said Delamater softly. "The President dies
to-morrow."

* * * * *

"No!" exploded the Chief. "Do you realize what that means? The
President murdered--more killings to follow--and the killer unknown!
Why the country will be in a panic: the whole structure of the
Government is threatened!"

He paused, then added as he struck his open hand upon the desk: "I
will have every available man at the White House."

"For witnesses?" asked Delamater coldly.

The big man stared at his operative; the lines of his face were
sagging.

"Do you believe--really--he can strike him down--at his desk--from a
distance?"

"I know it." Delamater's fingers played for a