.

But the room was empty! Mystified, the girls, their chaperone and Mr.
Blackford, stared about it. No Mollie was there!

"But I'm sure she was thrust into this room by that figure in white,"
declared Betty. "We all saw it."

"Are you sure?" asked Mr. Blackford, slowly.

"Positive. She was put in this room for some unknown purpose, and she
can't have gotten out, for we have been in the hall all the while, and
the door was locked."

"There is the window," said Mr. Blackford, as he took the lantern from
Betty. Walking over to the casement he uttered an exclamation, as he saw
the bent bars.

"This explains it!" he cried. "She has escaped!"

"Or else the--the ghost--came in here and took her away," faltered Amy.

"Well, we'll have a look about outside," suggested the young man. "There
may be marks that will aid us, especially as the ground is soft now."

They all went outside. The rain was but a mere drizzle now. The fury of
the storm had passed, and the night was becoming calm. The old house,
and the mansion beyond it, which could now be seen dimly back of a
fringe of trees, was silent and seemingly deserted, even by the ghost.
There were no more queer blue flames, no more hollow groans and clanking
noises.

"I didn't think to look and see if the other auto lamp was in that room
where poor Mollie was," said Grace. "Did you?"

"Yes," spoke Betty. "I looked. It was gone."

"We had better not all go under that window at once," suggested Mr.
Blackford, as they neared the casement with the bent bars. "Let me go
alone, with the light, and I'll see if I can make out any footprints."

Carefully he examined, and then he gave a joyful exclamation.

"It's all right!" he cried. "There are the marks of but one person's
shoes, and they are your friend's, I'm sure--for they are small. It
plainly shows where she let herself down out of the window."

"Oh, how glad I am!" cried Betty. "But where is she now? Can you tell
which way she went?"

"Only for a short distance," answered Mr. Blackford, as he flashed the
rays of the lamp to and fro. "Then comes grass, and I am not
sufficiently good on the trail to track a person over grass. However,
we are sure of one thing--that she got out of the room herself, and ran
off. She was not carried away."

"That is everything," murmured Grace. "Oh, what a relief!"

"But where can she be now?" asked Betty, in bewilderment. "Why did she
not come back to us?"

"Probably she thought