“Listen!” put in Fred quickly. “If it’s just the same to you fellows, keep this to yourselves, will you?”

“Sure!” answered Phil. “I won’t say a word if you don’t want me to.” And to this Fatty also agreed.

The soot had certainly made a great mess, and it took the Rover boys the best part of half an hour to put the room in order. Luckily, their school books were not damaged quite as much as they had at first supposed, and by dusting them off with care they made the volumes fairly presentable. The essay papers, however, were spoiled, and both Jack and Fred decided they would have to be written over again.

“I’m going to get up real early to-morrow morning and do it,” said Jack, and his cousin agreed to do the same.

Then the boys brushed their uniforms as best they could, and after that each took a bath, which made them feel better.

“I’m going to snoop around a little and see if I can get on the track of the rascal who played this trick,” announced Randy, after he had donned clean clothing.

“And I’ll go with you,” answered his brother.

It still lacked half an hour of time to retire, and the others availed themselves of this to start the new copies of their essays. Just as the “lights out” bell was ringing the twins came in again.

“Nothing doing,” announced Andy, with a disappointed look on his otherwise cheerful face. “All of the cadets look as meek as lambs.”