“They’re after us!” cried Jerry.

“Yes, but they’ve got to catch us!” declared Bob.

An instant later a puff of white smoke spurted out from the side of the Monarch, something black jumped from wave-crest to wave-crest.  Then came a dull boom.

“What’s that?” asked Bob, in alarm.

“A shot across our bows.  A command to lay to,” said Mr. De Vere.

CHAPTER XXX

 The end of Blowitz—­ conclusion

“Are you going to stop?” asked Ned, of Maurice De Vere.

“Not unless you boys are afraid.  I don’t believe they can hit us.  That’s only a small saluting cannon they have, and it’s hard to shoot straight when there’s as much sea on as there is now.  Do you want to stop and surrender?”

“Not much!” cried the three motor boys in a breath.

“Then may it be a stern chase and a long chase!” exclaimed Mr. De Vere.  “Crowd her all you can, Ned, and we’ll beat him.”

Ned needed no urging to make the powerful motor do its best.  The machinery was throbbing and humming, and the Ripper was cutting through the water “with a bone in her teeth,” as the sailors say.

“Swing her around so as to get the tug in back of us,” advised Jerry.  “We’ll be in less danger then.”

Ned shifted the wheel, but, as he was doing so there was another shot from the Monarch, and, this time, the ball from the cannon came uncomfortably close.

“Their aim is improving,” remarked Mr. De Vere, as he coolly looked at the pursuing tug through the glasses, “but we are leaving them behind.”

The chase had now become a “stern” one, that is the Monarch was directly astern of the Ripper, and the varying progresses made by the boats could not be discerned so well as before.  Still it seemed that the motor boat was maintaining her lead.

It now settled down to a pursuit, for, stern on as she was, the Ripper offered so small a mark for the tug, that it was almost useless to fire the cannon.

There were anxious hearts aboard the motor boat, as they watched the tug pursuing them.  They knew there would be a fight if Blowitz and Mr. De Vere met, and, in the latter’s crippled condition, it was not hard to imagine how it would result.

“How’s she running, Ned?” asked Jerry, as he looked at the engine.

“Never better.  She’s singing like a bird.  This is a dandy boat.”

“I think we’ll beat him,” declared Mr. De Vere.

For an hour or more the chase continued, the Monarch seeming to gain slowly.  Mr. De Vere looked anxious, and kept his eyes fixed to the binoculars, through which he viewed the pursuing vessel.  At length, however, a more cheerful look came into his face.

“Something has happened!” he exclaimed.

“Happened?  How?” asked Jerry.

“Why aboard the tug.  Blowitz went off the deck in a hurry, and the steersman has left the pilot house.  Maybe something is wrong with the machinery.”