had seen, coming towards the pavilion, Mademoiselle Stangerson
--alone. He would never have dared to attack her at that hour, if
he had not found her alone. His mind was made up. He would be
more at ease alone with Mademoiselle Stangerson in the pavilion,
than he would have been in the middle of the night, with Daddy
Jacques sleeping in the attic. So he shut the vestibule window.
That explains why neither Monsieur Stangerson, nor the keeper, who
were at some distance from the pavilion, had heard the revolver shot.

"Then he went back to The Yellow Room. Mademoiselle Stangerson came
in. What passed must have taken place very quickly. Mademoiselle
tried to call for help; but the man had seized her by the throat.
Her hand had sought and grasped the revolver which she had been
keeping in the drawer of her night-table, since she had come to
fear the threats of her pursuer. The murderer was about to strike
her on the head with the mutton-bone--a terrible weapon in the
hands of a Larsan or Ballmeyer; but she fired in time, and the shot
wounded the hand that held the weapon. The bone fell to the floor
covered with the blood of the murderer, who staggered, clutched at
the wall for support--imprinting on it the red marks--and, fearing
another bullet, fled.

"She saw him pass through the laboratory, and listened. He was long
at the window. At length he jumped from it. She flew to it and
shut it. The danger past, all her thoughts were of her father. Had
he either seen or heard? At any cost to herself she must keep this
from him. Thus when Monsieur Stangerson returned, he found the door
of The Yellow Room closed, and his daughter in the laboratory,
bending over her desk, at work!"