“Pass me the megaphone, Mr. Dalzell,” he requested.

With this mouth-piece in hand, Dave watched the nearing craft.

The “Duncan” was a semi-speed boat, some forty-five feet over all, without cabin, and carrying only a sprayhood forward to protect its engine.

Two men appeared in the boat—­Mr Salisbury, the owner, and his engineer.  The latter was steering at this time.

Chug-chug-chug! came the fast craft.

Dave waited, well knowing that his hail could not carry to either engineer or owner over the noise that the “Duncan’s” engine was making.

Farley stood close to Dave watching.  The tillerman also had his eye on the approaching craft.  The other midshipmen, telling stories or staring out over the water, paid little heed.  There could be no danger from the motor boat.  Both the owner and engineer were well known, in these waters, as capable boat handlers and as men of judgment.

Darrin, himself, did not believe that there was any danger.

“Throw her head a point and a half off to the starboard,” called Dave Darrin evenly.

“Aye, aye, sir,” responded the midshipman tillerman, and the sailboat responded slowly under the slight headway.

“Great Scott, don’t those fellows know that a sailboat has the right of way over a power craft?” demanded Darrin suddenly.

“Perhaps they’re going to see how close they can come to us without hitting us,” remarked Farley.

Dave raised the megaphone to his lips, waiting until he judged that there was a chance of his hail being heard.

“Duncan, ’ahoy!” bellowed Darrin.  “Go to port of us!”

Still the motor boat came onward, at a speed something better than fourteen miles.

“Hard-a-starboard!” Darrin roared back to his own tillerman.

Then he repeated his hail.  He was almost frenzied now; for the motor boat had not yet changed its course.

Suddenly, when the two craft were almost together, the engineer, after throwing over his wheel, held up one hand.

Before Dave could guess what the gesture meant, the “Duncan” loomed up on the sail-boat’s port bow, coming on at unabated speed.

There was an instant scampering of midshipmen for safety.  Then bump! the motor boat’s bow crashed into the sailboat, cutting a great gap in her.

The force of the shock threw most of the midshipmen into the water.  The rest jumped.

Now, the “Duncan” responded to her engine by backing off.  But the motor boat, too, had received her deathblow.  Ere she had backed off a hundred and fifty feet she began to fill rapidly.  Owner and engineer had only time to adjust life-preservers and leap overboard.  Then the “Duncan” went down.

At the moment of collision there was a crash of spars and a snapping of cordage.  The sailing craft’s mast had gone by the board, though not much before the sailboat itself had filled.