"Have you looked through the upper part of the house?" Ashton-Kirk asked
Scanlon.

"No," replied Bat.

"I have," said the other. "That window is right at the head of a
stairway. Something is being said or done upon the lower floor which
rather upsets her."

He moved forward as he spoke; beneath the dimly-lighted window above was
a square, heavily made shutter different from the others in shape, and
marking a hall window. As they were about to pass it, Ashton-Kirk
uttered a low exclamation and stopped suddenly. The shutter was badly
fitted, having swollen with the weather, so that it could not be
completely closed. The slim, strong fingers of Ashton-Kirk gripped its
edge; slowly, carefully, with never a creak it opened. There was a white
curtain inside, but a pendant light made all things in the hall visible.
A flight of stairs led to the second floor, and at the foot of these
stood Fenton, one hand upon the rail, and the nurse, with frightened
face, was pleading with him, as though not to do something which he had
signified his intention of doing.

"Ah!" Scanlon heard Ashton-Kirk breathe. "So that's your game, is it?"
Then to Bat: "Stay here; keep an eye on that fellow, and be ready to
act."

With these words he slipped easily away into the darkness, and Scanlon
and Nora were left alone at the window.

"He is demanding to be allowed to see Mary," said the trembling voice of
Nora in Bat's ear. "And the poor nurse is terrified. See how she tries
to stop him!"

With a sort of snarl, the broken-nosed man threw off the detaining hand
of the nurse and turned a threatening face upon her, at the same time
gesturing toward the upper floor and signifying his intention of
ascending in spite of anything the girl might say.

"But she's got grit," said Bat, in a low tone of admiration. "She hangs
to him. The girl up-stairs is her patient, and she'll not have her
frightened. It's part of the training they get, I guess."

Fenton let go the stair rail and made a step toward the nurse; his ugly
face was distorted, and his hands were clenched. He began to speak; what
he said could not be heard by the watchers outside the window, but the
nurse seemed terrified and shrank from him.

"He's down to cases now," said Scanlon, as he deftly freed his revolver,
and held it ready, but in such a way that Nora could not see it.

"Look!" whispered Nora, thrillingly. "Look, Bat. On the stairs!"

Bat Scanlon shifted his eyes from the th