"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