ould not refuse a request so urged, but his
step was slow and his manner next to ungracious as he led the way to the
door of the adjoining room and threw it open.

Just what she had been told to expect! Bare walls and floors and an
empty chair! Yet she did not instantly withdraw, but stood silently
contemplating the panelled wainscoting surrounding her, as though she
suspected it of containing some secret hiding-place not apparent to the
eye.

Mr. Van Broecklyn, noting this, hastened to say:

"The walls are sound, Miss Strange. They contain no hidden cupboards."

"And that door?" she asked, pointing to a portion of the wainscoting so
exactly like the rest that only the most experienced eye could detect
the line of deeper colour which marked an opening.

For an instant Mr. Van Broecklyn stood rigid, then the immovable pallor,
which was one of his chief characteristics, gave way to a deep flush, as
he explained:

"There was a door there once; but it has been permanently closed. With
cement," he forced himself to add, his countenance losing its
evanescent colour till it shone ghastly again in the strong light.

With difficulty Violet preserved her show of composure. "_The_ door!"
she murmured to herself. "I have found it. The great historic door!" But
her tone was light as she ventured to say:

"Then it can no longer be opened by your hand or any other?"

"It could not be opened with an axe."

Violet sighed in the midst of her triumph. Her curiosity had been
satisfied, but the problem she had been set to solve looked
inexplicable. But she was not one to yield easily to discouragement.
Marking the disappointment approaching to disdain in every eye but Mr.
Upjohn's, she drew herself up--(she had not far to draw) and made this
final proposal.

"A sheet of paper," she remarked, "of the size of this one cannot be
spirited away, or dissolved into thin air. It exists; it is here; and
all we want is some happy thought in order to find it. I acknowledge
that that happy thought has not come to me yet, but sometimes I get it
in what may seem to you a very odd way. Forgetting myself, I try to
assume the individuality of the person who has worked the mystery. If I
can think with his thoughts, I possibly may follow him in his actions.
In this case I should like to make believe for a few moments that I am
Mr. Spielhagen" (with what a delicious smile she said this). "I should
like to hold his thesis in my hand and be interrup