rk of a moment to tie one end of the rope to a heavy staple
driven under the window sill, and then, closing her eyes to the pitch
black void beneath her, Betty let herself slide down to the roof. Her
hands were cruelly scratched by the rope fibres and she was too tired to
care about the evidences of her flight.

"If anybody wants to know about that rope and the locked door, let 'em!"
she sighed defiantly.

Bobby woke up as Betty came in the door, and then there were questions
galore to be answered. Betty was covered with dust and her clothing was
torn and rumpled. Bobby declared she looked as if she had been to war.

"I feel it," admitted Betty. "Let me take a hot bath and get into bed.
And, Bobby, promise me on your word of honor that you'll call me in the
morning. Whoever locked me in expects me to stay there till I'm missed,
and I want to walk into breakfast as usual."

She half regretted her instructions when Bobby called her at seven the
next morning, but Betty was nothing if not gritty, and she sleepily
struggled into her clothes. Ada Nansen's look of utter astonishment when
she saw Betty come into the dining room with the rest for breakfast told
those in the secret what they had already suspected.

"Bobby must have heard her listening at our door last night," said
Betty. "What am I going to do? Why nothing, of course! That was part of
the stunt, or at least I'm going to consider it so. My card is there, so
they'll know I fulfilled my part."

Dave McGuire scratched his head when he found the rope and the open
window, but he wisely said nothing. He had two keys, and one he had
loaned at the request of the senior class president to a fellow student.
The other key, for emergency use, hung on a nail in the fourth story
hall. That was the key Dave found in the door lock when he made his early
morning tour of inspection. "But the young folks must be having their
fun," he said indulgently, "and, short of burning down the place, 'tis
not Dave McGuire who will be interfering with 'em."

Mid-term tests were approaching. Bobby, who, with all her love of fun,
was a hard student, felt prepared and went around serenely. Constance
Howard had, most humanly, neglected, so far as the teacher of mathematics
permitted, the study that was hardest for her, her algebra. She now spent
hours in "cramming" on this, meanwhile complaining to those of her
special chums who would listen to her of "the unfairness of being made to
study a