e detective's first move was to ascertain whether or not the building
had any rear exit, by which Grace might have left, without being seen by
Leary. He walked down the avenue to its rear wall, only to find that it
abutted against the wall of the next building. There was no rear
entrance.

If, then, Grace had not left the place during the past hour, she must
still be in one of the ten flats that formed the five floors of the
building. But which one? That, apparently, was the problem he had to
solve.

It would be useless, he felt, to inquire at the doors of the various
apartments at this hour of the morning. Admission, at least on the part
of those he sought, would certainly be refused. Yet he felt that there
was no time to be lost.

Stationing Leary before the front door, with instructions to keep a
careful watch, Duvall went into the vestibule, and by means of his
pocket light, inspected the names of the occupants of the building, as
Grace had done a short time before. The hallway inside was dark, with
the exception of a dim light at the foot of the stairs. Apparently the
place boasted no elevator or hall-boy service.

The ten names on the boxes in the vestibule meant nothing to him. How
was it possible to determine which one was that of the woman he sought?
Weinberg--Scully--Martin--Stone--he ran down the list, trying to find
some distinguishing mark, some clue, that would guide him.

Suddenly he paused, allowing the light from his torch to rest upon the
card bearing the name of one of the tenants on the fourth floor.

This card had attracted his attention, because it was different from any
of the others in the two racks. They were either engraved or printed
visiting cards, stuck inside the brass frames provided for them, or the
names were written or printed by hand upon blank cards. But this card,
bearing simply the inscription E. W. Norman, was neither engraved nor
printed, nor written by hand. On the contrary, it was _typewritten_.

This in itself at once attracted Duvall's attention, owing to the fact
that the various letters received by Ruth Morton had also all been
typewritten. If the name, Norman, was an assumed one, as Duvall
concluded it to be, what more natural than that it should be
_typewritten_ on a blank card, especially when a regular printed or
engraved card was not available; when to have it written in long hand
would have been a disclosure of identity, and when, above all, the woman
in questi