“I’m going to make a big try,” answered his companion.

“They’re heading out into the middle of the lake!” cried the eccentric man.

“If they do, I can cut them off!” murmured Tom as he put the wheel over.

But whoever was steering the arrow knew better than to send it on a course that would enable the pursuing boat to cut across and shorten the distance to it.  After sending the stolen craft far enough out from shore to clear points of land that jutted out into the lake, the leading boat was sent straight ahead.

“A stern chase and a long chase!” murmured Mr. Damon.  “Bless my rudder, but those fellows are not going to give up easily.”

“I guess not,” murmured Tom.  “Will you steer for a while, Mr. Damon?”

“Of course I will.  If I could get out and pull the boat after me, to make it go faster, I would.  But as I always lose my breath when I run, perhaps it’s just as well that I stay in here.”  Tom thought so too, but his attention was soon given to the engine.  He adjusted the timer to get if possible a little more speed out of the boat he had borrowed from Andy, and he paid particular attention to the oiling system.

“We’re going a bit faster!” called Mr. Damon’ encouragingly, “or else they’re slacking up.”

Tom peered ahead to see if this was so.  It was hard to judge whether he was overhauling the arrow, as it was a stern chase, and that is always difficult to judge.  But a glimpse along shore showed him that they were slipping through the water at a faster speed.

“They’re up to something!” suddenly exclaimed Mr. Damon a moment later.  “I believe they’re going to fire on us, Tom.  They are pointing something this way.”

The lad stood up and gazed earnestly at his boat, which seemed to be slipping away from him so fast.  One of the occupants was in the stern, aiming some glittering object at those in the red streak.  For a moment Tom thought it might be a gun.  Then, as the man turned, he saw what it was.

“A pair of marine glasses,” cried the lad.  “They’re trying to make out who we are.”

“I guess they know well enough,” rejoined Mr. Damon.  “Can’t you go any faster, Tom?”

“I’m afraid not.  But we’ll land them, sooner or later.  They can’t go very far in this direction without running ashore and we’ll have them.  They’re cutting across the lake now.”

“They may escape us if it gets dark.  Probably that’s what they’re working for.  They want to keep ahead of us until nightfall.”

The young inventor thought of this too, but there was little he could do.  The motor was running at top speed.  It could be made to go faster, Tom knew, with another ignition system, but that was out of the question now.

The man with the glasses had resumed his seat, and the efforts of the trio seemed concentrated on the motor of the arrow.  They, too, wished to go faster.  But they had not skill enough to accomplish it, and in about ten minutes, when Tom took another long and careful look to ascertain if possible whether or not he was overhauling the thieves, he was delighted to see that the distance between the boats had lessened.