all influence over her. It would be hopeless to expect her to
respond to your will."

"I have already abandoned it," Powers answered. "I curse the day and the
thought which made me ever attempt it."

"It is as well, then," Trowse answered, "to give you fair warning. I do
not propose to stand by quietly and watch your folly."

"What do you mean?" Powers demanded.

"This: That if you do not carry this thing through--I shall!"

Powers sprang to his feet, his face was dark with passion.

"If you should dare to interfere," he cried, "if you should make the
slightest attempt to----"

"Stop!"

The monosyllable came like a pistol-shot, incisive, compelling! There
was a breathless silence. Trowse continued, and his words were cold and
hard.

"Do not threaten me," he said. "You should know better than that. You
should know exactly of how much account I hold my life when it comes to
a question of adding to the sum of human knowledge. I shall do as I say.
My decision is unalterable."

Powers was a man again.

"It is well to be prepared," he said. "I thank you for your warning.
Take mine in return. I have as little fear of death as you, and I think
that my love for Eleanor is a passion as strong as your devotion to
science. I tell you that I will not have her made the subject of your
experiments. I will not have her life or reason imperiled, even to solve
the greatest of all mysteries."

Trowse shrugged his shoulders.

"I think," he said, "that we understand one another perfectly."

Their talk fanned a growing distrust of Trowse that Fiske had felt for
weeks. He knew the man's hypnotic power, he saw the fascination with
which his friend haunted Eleanor's side at gatherings where her clear
bright laugh would suddenly cease and a look almost of terror creep into
her eyes with Trowse's entrance. Then she forgot every one else and
yielded herself to his spell.

Very subtly, very deftly, Trowse pursued his cold-blooded course of
experiment while Powers in vain sought to end it. At last he forbade
Trowse to enter his home and all went well until returning one day, at
an unexpected hour, Powers heard from his library ringing through the
house, through closed doors and curtained hallways, the cry of a woman
in mortal fear.

He sprang to the door and threw it open. Outside all was silent. There
was no repetition of the cry. Then a fainter sound reached him--a low,
convulsive moaning as of some creature in pain. He cross