“How comes it that you are up here?” went on Tom.

“I am stopping with friends, who have a cottage near the Lakeview Hotel.  They have a motor-boat and I got Dick Blythe—­he’s the owner of this—­to show me how to run it.  I thought I knew, and I started out a little while ago.  At first it went beautifully, but a few minutes ago it blew up, or—­or something dreadful happened.”

“Nothing very dreadful, I guess,” Tom assured her.  “I think I can fix it.”  He got into the other boat and soon saw what the trouble was.  The carburetor had gotten out of adjustment and the gasoline was not feeding properly.  The young inventor soon had it in order, and, testing the motor, found that it worked perfectly.

“Oh, I can’t thank you enough,” cried Miss Nestor with a flash from her brown eyes that made Tom’s heart beat double time.  “I was afraid I had damaged the boat, and I knew Dick, who is a sort of second cousin of mine, would never forgive me.”

“There’s no harm done,” Tom assured her.  “But you had better keep near us on your way back, that is, if you are going back.”

“Oh, indeed I am.  I was frightened when I found I’d come so far away from shore, and then, when that explosion took place—­well, you can imagine how I felt.  Indeed I will keep near you.  Are you stopping near here?  If you are, I wish you’d come and see me, you and Mr. Newton” she added, for Tom had introduced his chum.

“I’ll be very glad to,” answered our hero, and he told how he happened to be in the neighborhood.  “I’ll give you a few lessons in managing a boat, if you like,” he added.

“Oh, will you?  That will be lovely!  I won’t tell Dick about it, and I’ll surprise him some day by showing him how well I can run his boat.”

“Good idea,” commented Tom.

He started the motor for Miss Nestor, having stopped it after his first test, and then, with the Dot, which was the name of the small boat Miss Nestor was in, following the larger arrow, the run back to the hotel was made.  The young lady turned off near the Lakeview dock to go to the cottage where she was stopping and the lads tied up at the hotel boathouse.

“Yes, we are in for a storm,” remarked Tom as he and his chum walked up toward the hotel.  “I wonder how dad is?  I hope the outing is doing him good.”

“There he comes now,” observed Ned, and, looking up, Tom saw his father approaching.  The young inventor was at once struck by the expression on his parent’s face.  Mr. Swift looked worried and Tom anxiously hastened forward to meet him.

“What’s the matter dad?” he asked as cheerfully as he could.  “Have you been figuring over that gyroscope problem again, against my express orders?” and he laughed a little.

“No, Tom, it’s not the gyroscope that’s worrying me.”

“What is it then?”

“Those scoundrels are around again, Tom!” and Mr. Swift looked apprehensively about him.