ut of the dining-room when the scream was heard, and when the
others rushed out of the dining-room on hearing the shot, the first
thing they saw was Miss Heredith descending the staircase of the wing in
which her nephew's wife had been murdered. Fortunately for Miss
Heredith, she was almost at the bottom of the staircase when she was
seen. The guests streamed out of the dining-room directly the shot was
heard, therefore it is impossible that Miss Heredith could have shot
Violet Heredith and then reached the bottom of the stairs so quickly.
She is able to establish an alibi of time, by, perhaps, half a minute.

"As all the members of the house party were in the dining-room at the
time, it is clear that they had nothing to do with the actual commission
of the crime. The next thing is the servants, and they also can be
excluded from suspicion. When we examined them this morning they were
all able to prove, more or less conclusively, that they were engaged in
their various duties at the time the murder was committed. The point is
that not one of them was upstairs in the left wing of the house when
Mrs. Heredith was shot.

"My original impression that the murder was not committed by a native of
the district has been deepened by our afternoon's investigations. Where,
then, are we to look for the murderer? To answer that question, in part,
let us first consider _how_ the murder was committed, and try and
reconstruct the circumstances in which the murderer must have entered
and left the house.

"Caldew thinks that the murderer entered the house by scaling the
bedroom window, and made his exit by the same means. He bases that view
on Miss Heredith's belief that the window was closed when she was in the
bedroom before dinner. After the murder was committed the window was
found open. But Miss Heredith's statement about the closed window does
not amount to very much. She does not actually know whether the window
was open or shut, because the window curtains were completely drawn at
the time she was in the room. Those curtains are so thick and heavy that
they would keep out the air whether the window was open or shut, and
account for the stuffy atmosphere in a room which had been occupied all
day.

"I do not regard the open window as a clue one way or the other. The one
thing we must not lose sight of is that nobody can say definitely when
it was opened. It may have been opened by Mrs. Heredith herself before
Miss Heredith came