blankets in the boat. As the young inventor entered the craft he uttered an exclamation.
"What's the matter?" asked Ned.
"I was sure I locked the sliding door of that forward compartment," was the reply. "Now it's open." He looked inside the space occupied by the gasoline tank and cried out: "One of the braces is gone! There's been some one at my boat in the night and they tried to damage her."
"Much harm done?" asked Ned anxiously.
"No, none at all, to speak of," replied Tom. "I can easily put a new block under the tank. In fact, I don't really need all I have. But why should any one take one out, and who did it? That's what I want to know."
The two lads looked carefully about the dock and boat for a sign of the missing block or any clews that might show who had been tampering with the Arrow, but they could find nothing.
"Maybe the block fell out," suggested Ned.
"It couldn't," replied Tom. "It was one of the new ones I put in myself and it was nailed fast You can see where it's been pried loose. I can't understand it," and Tom thought rapidly of several mysterious occurrences of late in which the strange man at the auction and the person he had surprised one night in the boathouse had a part.
"Well, it needn't delay our trip," resumed the
