emark plainly produced a sensation. The preacher cast a
significant glance at the mother, and the girl looked away at the
lamp, a flush upon her face.

"Hello!" exclaimed Serviss, under his breath. "Have I discovered a
neat of cranks? I've been enlisted on somebody's side--I wonder
whose?"

The clergyman faced him again and calmly asked: "Have you ever
_investigated_ these occult phenomena?"

"Certainly not. I have no time to waste on such imaginings. My time is
all taken in a study of certain definite processes in the living
organism."

A light began to glow in the eyes of the young clergyman. "I suppose
you class mental healing among the delusions?"

"Most assuredly I do," answered Serviss, with the remorselessness of
youth.

"You would say that the mind of man cannot mend the body of another--"

"If you mean directly--in the manner of 'faith cures' and the like--I
would answer certainly not, unless the disorder happens to be in
itself due to a delusion. I can imagine the hypochondriac being cured
by mental stimulus." He felt that he was drawing near the point at
issue, and his eyes shone with glee.

The preacher set his trap. "You believe in the action of a drug--say,
prussic acid--you believe it will kill?"

"Yes, and quite irrespective of the opinion of the one who takes it.
His thinking it water will not check or change its action in the
slightest degree."

"But _how_ does it kill?" persisted Clarke. "What does it _do_?"

"If you mean why, at the last analysis, does one drug attack cells and
the other nourish them, I answer, frankly, I don't know--nobody
knows."

Clarke pursued his point. "Under the microscope, the germ of, say,
tetanus is a minute bar with spore at the end like the head of a
tadpole. Of what is this cell composed?"

"Probably of a jelly-like substance with excessively minute filaments,
but we don't know. We are at the limit of the microscope. We trace
certain processes, we even dissect certain cells, but elemental
composition of plasm remains a mystery."

The preacher glowed with triumph. "Then you confess yourself baffled?
The union of matter and spirit is beyond your microscope. What do you
know about a drop of water? You say it is formed of hydrogen and
oxygen in such and such proportions. What _is_ hydrogen? Why do they
unite?"

"I don't know," calmly replied Serviss. "We admit that any material
substance remains inexplicable. The molecule lies far below the line
of visi