or
any one to pretend to be insane."

"Really? I should have thought it quite possible," said I.

"No. It is impossible. I was once called to give my opinion in such a
case. The man betrayed himself in half an hour, and yet he was a very
clever fellow. He was a servant; murdered his master to rob him; was
caught, but succeeded in restoring the valuables to their places, and
pretended to be crazy. It was very well managed and he played the fool
splendidly, but I caught him."

"How?" I asked.

"Simply by bullying. I treated him roughly, and never stopped talking to
him,--just the worst treatment for a person really insane. In less than
an hour I had wearied him out, his feigned madness became so fatiguing
to him that there was finally only a spasmodic attempt, and when I had
done with him the sane man was perfectly apparent. He grew too much
frightened and too tired to act a part. He was hanged, to the
satisfaction of all concerned, and he made a complete confession."

"But how about the artificial insanity you spoke of? How can it be
produced?"

"By any poison, from coffee to alcohol, from tobacco to belladonna. A
man who is drunk is insane."

"I wonder whether, if a madman got drunk, he would be sane?" I said.

"Sometimes. A man who has delirium tremens can be brought to his right
mind for a time by alcohol, unless he is too far gone. The habitual
drunkard is not in his right mind until he has had a certain amount of
liquor. All habitual poisons act in that way, even tea. How often do you
hear a woman or a student say, 'I do not feel like myself to-day,--I
have not had my tea'! When a man does not feel like himself, he means
that he feels like some one else, and he is mildly crazy. Generally
speaking, any sudden change in our habits of eating and drinking will
produce a temporary unsoundness of the mind. Every one knows that
thirst sometimes brings on a dangerous madness, and hunger produces
hallucinations and visions which take a very real character."

"I know,--I have seen that. In the East it is thought that insanity can
be caused by mesmerism, or something like it."

"It is not impossible," answered the scientist. "We do not deny that
some very extraordinary circumstances can be induced by sympathy and
antipathy."

"I suppose you do not believe in actual mesmerism, do you?"

"I neither affirm nor deny,--I wait; and until I have been convinced I
do not consider my opinion worth giving."

"That is the