"It's very kind of you to offer them, and, since you will have no need for them, I'll be glad to take them off."

"Come down to my boat," invited Tom, using the word "my" with a proper pride, "and I'll take off the brass letters. I have a screw driver in my motor-cycle tool bag."

As the former and present owners of the ARROW (which is the name by which I shall hereafter designate Tom's motor-boat) walked down toward the dock where it was moored the young inventor gave a startled cry.

"What's the matter?" asked Mr. Hastings.

"That man! See him at my motor-boat?" cried Tom. He pointed to the craft in the lake. A man was in the cockpit and seemed to be doing something to the forward bulkhead, which closed off the compartment holding the gasoline tank.

"Who is he?" asked Mr. Hastings, while Tom started on a run toward the boat.

"I don't know. Some man who bid on the boat at the auction, but who didn't go high enough," answered the lad. As he neared the craft the man sprang out, ran along the lakeshore for a short distance and then disappeared amid the bushes which bordered the estate of Mr. Hastings. Tom hurriedly entered the ARROW.

"Did he do any damage?" asked Mr. Hastings.

"I guess he didn't have time," responded Tom. "But he was tampering with the lock on the door of the forward compartment. What's in there?"

"Nothing but the gasoline tank. I keep the bulkhead sliding door locked on general principles. I can't imagine what the fellow would want to open it for. There's nothing of value in there. Perhaps he isn't right in his head. Was he a tramp?"