e mean!"

However, the door was locked and she was a prisoner. It was inky black
and at every step she seemed to knock over something or stumble against
cold iron. Gradually her eyes became accustomed to the lack of light, and
she made out the outlines of something against the wall.

"Why, there is a window--I remember!" she said aloud. "I wonder if I can
reach it."

Cautiously she felt her way around and stretched up tentative fingers.
She could barely touch the lower frame.

Then, for the first time, Betty felt a little shiver of fear and
apprehension. It was close in the tower room, and the smell of oil and
dead air began to be oppressive. She had no wish to shout, even if she
could be heard, a doubtful probability, for she had no mind to be rescued
before the curious eyes of the entire school.

"I'll get out of it somehow, if I have to stay here all night," she told
herself pluckily. "Oh, my goodness, what was that?"

A tiny sawing noise in one corner of the room sent Betty scurrying to
the other side. She would have indignantly denied any fear of mice or
rats, but the bravest girl might be excused from a too close
acquaintance thrust upon her in the dark. Betty had no wish to put her
fingers on a mouse.

"How can I get out?" she cried aloud, a little wildly. "I can't breathe!"

In the uncanny silence that followed the sound of her voice, the sawing
noise sounded regularly, rhythmically. In desperation Betty seized an
iron crowbar she had backed into on the wall, and hurled it in the
direction of the industrious rodents.

"Now I've done it," she admitted, as with a clatter and a bang that, she
was sure, could be heard a mile away, an evident avalanche of tools
tumbled to the floor. Her crowbar had struck a box of tools.

But the silence shut down again after that. Betty did not realize that
the water tower was so isolated that even unusual noises inside it would
not carry far, and with the door and the window both closed the room was
practically sealed.

The sawing noise was not repeated, there was that much to be grateful
for, Betty reflected. She wondered if she could batter down the door.

"I'll try, anyway," she thought wearily.

And then she could not find the crowbar! Around and around she went,
feeling on the floor for the tools that had clattered down with such a
racket and for the iron bar she had hurled among them. Not one tool could
she put her hands on.

"I must be going crazy," she crie