"Somebody is playing us tricks," said Dave. "I thought so before and now I am certain of it. I shouldn't wonder if that somebody had gone and told Mike Marcy to look out for ghosts at the end of his lot."

"Who would do it?"

"Several fellows—Link Merwell, Nat Poole, and their cronies."

"Never mind that crowd now," said Shadow. "How are we to get into the school without waking anybody up?"

"Let us try all the doors and lower windows," suggested the shipowner's son.

This was done, and at last one of the boys found a basement window unfastened. He notified the others.

"I know where that leads to," said Dave. "The laundry."

"Yes, I've been in the laundry, too," added the senator's son.

"Then one of you see if you can get upstairs through the laundry and let us in," said Buster. "And please don't be all night about it either, for I am getting cold."