“We wanted to attract attention,” answered Pepper, calmly.

“I want you to keep quiet!”

“Mr. Crabtree, will you tell us why we are prisoners here?” asked Jack.

“You are prisoners because you have disobeyed the rules of this institution,” snapped the instructor, and there was a certain gleam of triumph in his eyes.

“How have we disobeyed the rules?”

“You know well enough.”

“We don’t know,” came from Pepper.

“Don’t contradict, Ditmore! Captain Putnam and myself have found you out.”

“Won’t you please explain?” asked Jack, as calmly as he could.

“Well, in the first place, you are responsible for the fire at the boathouse.”