t to be alone downstairs," Ruth insisted. "Uncle would
not like it. I am going to peep in on her, and then make her come on
upstairs to bed."

Ruth led the way, with Bab at her heels. But it occurred to Barbara that
the midnight visitor to Mr. Hamlin's study might be some one other than
his daughter. Bab did not know whether Mr. Hamlin kept any money in his
strong box in the study. She and Ruth were both unarmed, and might be
approaching an unknown danger. Quick as a flash Bab arranged a little
scheme of defense.

There were two old-fashioned square stools placed on opposite sides of
the hall. Without a word to Ruth, who was intent on her errand, Bab drew
out these two stools and placed them side by side in the immediate centre
of the hall. Any one who tried to escape from the study would stumble
over these stools and at once alarm the household. Of course, if Bab and
Ruth found Harriet in her father's study Bab could warn them of her trap.

"What shall we do, Bab?" Ruth asked when Barbara joined her. "The light
is still shining in the study. But I do not want to knock on the door; it
would frighten Harriet. And it would terrify her even more if we walked
right into the study out of this darkness. But we can't wait out here all
night. I am catching cold."

Barbara did not reply. They were in a difficult situation. Suppose
Harriet were in the study? They did not wish to frighten her. In case the
veiled figure was not Harriet any speech of theirs would give their
presence away.

"I think we had better open the door quickly and rush in," Ruth now
decided. "Then Harriet can see at once who we are."

Without waiting for further consultation with Bab, Ruth flung wide the
study door.

In the same instant the light in the room went out like a flash.

"Harriet, is that you?" Ruth faltered. There was no answer, save some
one's quick breathing. Ruth and Bab could both perceive that an
absolutely white figure was crouched in a corner of the room in the dark.

Bab moved cautiously toward the spot where she knew an electric light
swung just above Mr. Hamlin's desk. But it was so dark that she had to
move her hand gropingly above her head, for a moment, in order to locate
the light.

The veiled being in the corner must have guessed her motive. Like a
zephyr it floated past the two girls. So light and swift was its movement
that Bab's hand was arrested in its design. Surely a ghost, not a human
creature, had passed by them.