which as yet there is no explanation. I do not say that
we mistrust you, but I ask you to submit to this test."

"I refuse!" the Professor replied harshly.

"And I insist," Quest muttered.

The Professor drew a little breath. He sat back in his chair. His face
became still, his lips were drawn closely together. Lenora wheeled up the
machine and with deft fingers adjusted the fittings on one side. Quest
himself connected it up on the other. The Professor sat there like a
figure of stone. The silence in the room was so intense that the ticking
of the small clock upon the mantelpiece was clearly audible. The silent
battle of wills seemed like a live and visible struggle. The very
atmosphere seemed charged with the thrill and wonder of it. Never before
had Quest met with resistance so complete and immovable. For the first
time the thought of failure oppressed him. Even that slight slackening of
his rigid concentration brought relief to the Professor. Without any
knowledge as to the source of their conviction, the two girls who watched
felt that the Professor was becoming dominant. And then there came a
sudden queer change. The intangible triumph of the Professor's stony poise
seemed to fade away. His eyes had sought the corner of the room, his lips
quivered. The horror was there again, the horror they had seen before. He
crouched a little back. His hands were uplifted as though to keep off some
evil thing.

"Craig!" Lenora whispered. "He thinks he sees Craig again!"

Quest held up his hand. He realised that this was his moment. He leaned a
little farther forward. Sternly he concentrated the whole of his will
power upon his task. Almost at once there was a change. The Professor fell
back in the chair. The tense self-control had passed from his features,
his lips twitched. Simultaneously, the mirror for a moment was
clouded,--then slowly a picture upon it gathered outline and substance.
There was a jungle, strange, tall trees, and brushwood so thick that it
reached to the waists of the two men who were slowly making their way
through it. One was the Professor, clearly recognisable under his white
sun helmet; the other a stranger to all of them. Suddenly they stopped.
The latter had crept a yard or so ahead, his gun raised to his shoulder,
his eyes fixed upon some possible object of pursuit. There was a sudden
change in the Professor. They saw him seize his gun by the barrel and
whirl it above his head. He seemed suddenly