"I'm going to blow up some paper bags. You take this one and blow into it while I open the window. As soon as it is up burst your bag, and I'll get mine ready. Say when you are ready."
"DON'T SHOOT!"
"Ready!" whispered Bertie and up went the window, back shot the bolt and upon the silence of the night sounded a loud report quickly followed by a second.
"Hallo!" cried a surprised voice. "Here, Miss Linda, don't shoot."
The girls who had drawn back from the window clutched one another, but felt an immense relief.
There were footsteps on the porch and presently two figures appeared before the open window. "Hallo, in there," called someone. "It's only I, Berk Matthews, Miss Linda."
The two girls approached the window. "What in the world are you doing prowling around here at this time of night, trying our bolts and bars?" asked Linda, indignantly. "You scared us nearly to death."
"And don't you reckon you gave us a good scare. It is lucky you don't see one of us weltering in gore, Linda Talbot. Just like a girl to be reckless with fire-arms."
Bertie stifled a giggle and pinched Linda's arm.