“How do you mean?”

“They’re keeping in close to shore.  See?  Look on the chart.”

“I see twelve little black crosses about there.  What do they mean?  Oh, I get you.  ‘Emerson Rocks,’ eh?  But I don’t see them!”

“No, they’re sunken.  The Follow Me’s running as near them as she dares, hoping that we’ll try to cut the corner more and strike.  Those fellows know this coast as I know the inside of my hat!  But we’ll fool them this time!”

So close to the submerged danger did the Adventurer go that Perry, watching over the side, caught a glimpse of a dark mass under the green water.  Then the chase straightened out once more and Steve drew the throttle wide, experimented with the spark for a moment and sent the white cruiser surging along in pursuit.  There could be no doubt as to the outcome of the race.  It was only a question of time.  The thieves had staked all on the attempt to elude the Adventurer in the shallows, and now they were doomed to open water, for Plum Island ran straight and unbroken for seven miles, and not until the entrance to Newburyport Harbour was reached was there the smallest chance to slip out of sight.

Ossie announced that dinner would be ready in a few minutes, but no one paid any attention.  Every eye was fixed on the Follow Me, which, dead ahead, was scurrying along at a rate which Tom, who had thought he knew the engine thoroughly, marvelled at.  But the distance was shortening between pursued and pursuer.  Off the life-saving station the fleeing craft was scarcely a hundred yards in advance, and it became more and more certain that the boats would be on even terms long before the seven-mile stretch was half traversed.

Wink went below and summoned Harry Corwin down from his perch, much to the relief of Ossie, whose preparations for dinner had not been made easier by having to dive under the table every time he sought the ice-chest, and posted him at a port in the forward cabin.  “If they won’t give up,” he explained, “we’ll have to go on plugging them.  I’ll take it in the other cabin.  Better fire first from one port then from another.  That’ll keep them guessing.  It’s just as well for them not to know that we’ve got only two pieces of artillery!”

“All right,” said Harry, “but there’s no use staying here now, is there?  There’s nothing in sight but a sea-gull!”

“No, but be ready when we get abreast, Harry.  I think that gun pulls to the right a little.  You might watch it.”

Wink returned to the deck, followed by Harry as far as the companion, and looked forward at the Follow Me.  Since he had gone below the positions of the boats had altered noticeably, and now, had he wished, he might easily have put a bullet through the mahogany door beyond the cockpit.  Steve was bearing seaward a little, intending to run up on the starboard side of the black cruiser.

“I’ll bet they’re doing a whole lot of thinking about now,” said “Brownie.”  “Guess I’ll go down and sit on the floor again.  They’ll be able to plug us in another minute or so.”