udy it a bit, if possible, and--"

"Tell me!"

"I took an experimental dose. I starved for six hours to hasten the
effect, locked myself into this room, and gave orders not to be
disturbed. Then I swallowed the stuff and waited."

"And the effect?"

"I waited one hour, two, three, four, five hours. Nothing happened. No
laughter came, but only a great weariness instead. Nothing in the room
or in my thoughts came within a hundred miles of a humorous aspect."

"Always a most uncertain drug," interrupted the doctor. "We make very
small use of it on that account."

"At two o'clock in the morning I felt so hungry and tired that I decided
to give up the experiment and wait no longer. I drank some milk and went
upstairs to bed. I felt flat and disappointed. I fell asleep at once and
must have slept for about an hour, when I awoke suddenly with a great
noise in my ears. It was the noise of my own laughter! I was simply
shaking with merriment. At first I was bewildered and thought I had been
laughing in dreams, but a moment later I remembered the drug, and was
delighted to think that after all I had got an effect. It had been
working all along, only I had miscalculated the time. The only
unpleasant thing _then_ was an odd feeling that I had not waked
naturally, but had been wakened by some one else--deliberately. This
came to me as a certainty in the middle of my noisy laughter and
distressed me."

"Any impression who it could have been?" asked the doctor, now listening
with close attention to every word, very much on the alert.

Pender hesitated and tried to smile. He brushed his hair from his
forehead with a nervous gesture.

"You must tell me all your impressions, even your fancies; they are
quite as important as your certainties."

"I had a vague idea that it was some one connected with my forgotten
dream, some one who had been at me in my sleep, some one of great
strength and great ability--of great force--quite an unusual
personality--and, I was certain, too--a woman."

"A good woman?" asked John Silence quietly.

Pender started a little at the question and his sallow face flushed; it
seemed to surprise him. But he shook his head quickly with an
indefinable look of horror.

"Evil," he answered briefly, "appallingly evil, and yet mingled with the
sheer wickedness of it was also a certain perverseness--the perversity
of the unbalanced mind."

He hesitated a moment and looked up sharply at his interlocutor. A