r
chamber at midnight. She did not see them, and undressed by the
uncertain glimmer of the night light. She went to bed, worn-out by
anxiety and fear--a fear that had made her remain in the laboratory as
late as possible.

"My reasoning had thus brought me to the second phase of the tragedy,
when Mademoiselle Stangerson was alone in the room. I had now to
explain the revolver shots fired during the second phase. Cries of
'Help!--Murder!' had been heard. How to explain these? As to the cries,
I was in no difficulty; since she was alone in her room these could
result from nightmare only. My explanation of the struggle and noise
that were heard is simply that in her nightmare she was haunted by the
terrible experience she had passed through in the afternoon. In her
dream she sees the murderer about to spring upon her and she cries,
'Help! Murder!' Her hand wildly seeks the revolver she had placed within
her reach on the night-table by the side of her bed, but her hand,
striking the table, overturns it, and the revolver, falling to the
floor, discharges itself, the bullet lodging in the ceiling. I knew
from the first that the bullet in the ceiling must have resulted from
an accident. Its very position suggested an accident to my mind, and
so fell in with my theory of a nightmare. I no longer doubted that the
attack had taken place before Mademoiselle had retired for the night.
After wakening from her frightful dream and crying aloud for help, she
had fainted.

"My theory, based on the evidence of the shots that were heard at
midnight, demanded two shots--one which wounded the murderer at the time
of his attack, and one fired at the time of the nightmare. The evidence
given by the Berniers before the examining magistrate was to the effect
that only one shot had been heard. Monsieur Stangerson testified to
hearing a dull sound first followed by a sharp ringing sound. The dull
sound I explained by the falling of the marble-topped table; the ringing
sound was the shot from the revolver. I was now convinced I was right.
The shot that had wounded the hand of the murderer and had caused it
to bleed so that he left the bloody imprint on the wall was fired by
Mademoiselle in self-defence, before the second phase, when she had been
really attacked. The shot in the ceiling which the Berniers heard was
the accidental shot during the nightmare.

"I had now to explain the wound on the temple. It was not severe enough
to have been mad