“The aviator didn’t say what went wrong,” answered Fred. “Perhaps he didn’t know himself. But one thing is sure—the biplane bobbed around from one side to the other several times before it headed down into the lake.”

“Well, they can all be thankful they escaped with their lives,” said one of the bystanders, and in this statement everybody concurred.

The Rover boys telephoned to the military academy and gave the head of that institution a few of the particulars of what had occurred. Colonel Colby had heard nothing about the aeroplane accident, and was, of course, much surprised. He readily gave the boys permission to remain in town for an hour longer in order that they might ascertain more of Mr. Stevenson’s real condition.

A motor boat had been sent to the scene of the wreck, and this presently returned with Tom Bossick on board.

“The cadets in the other rowboat have returned to their school,” said the aviator. “We found that the aeroplane was under less than twenty feet of water, so I have hopes that we can raise her and maybe have her repaired, or at least save the engine. I think she rests on that sandbar one of you young fellows mentioned.”

“And what went wrong?” questioned Fred eagerly.

“I think the motor got loose somehow. We’ll have to investigate after we raise the biplane—if we ever do.”

A little later the four Rover boys went to the hotel. There they encountered Jack’s sister Martha and Fred’s sister Mary, who had just come over from Clearwater Hall with some dry clothing for Ruth. Of course the two Rover girls were greatly excited, and they rushed at their brothers and their cousins, demanding to know if they were perfectly all right.

“Sure we are!” declared Fred. “Why, I wasn’t even in the water!”