Chapter 13 A CHALLENGE ACCEPTED

Captain Putnam looked at both cadets sharply.

"Both of you suspect somebody, is that it?" he said, slowly.

"We do," said Pepper.

"But you are not certain?"

"We are not certain, and therefore it would not be right for us to mention any names," said Jack.

"Now tell me the truth of your trouble with Mr. Crabtree," pursued the captain, a