the light playing on this wall most of the way. If he
had run back we would have seen him, even if he hadn't hailed. And he
couldn't have run farther out to seaward. Evarts, I'm downright worried."

Tom Reade might indeed well be worried over the grewsome mysteries of this
night of evil deeds.

CHAPTER IV

SOME ONE CALLS AGAIN

Half an hour later Tom Reade leaped ashore at the little pier.

"My orders, Mr. Reade."

"They're brief and concise," Tom rejoined. "You're to cruise the length
of the wall, especially farther out from shore. Use your searchlight
freely. Keep the wall so guarded that no rascal can slip out there, either
over the wall or by boat, and do any damage. Mr. Evarts, the safety of
the wall until daylight is your whole charge."

"Very good, sir. But I'm sure that nothing more will happen to the wall."

"If anything does it will be up to you, Mr. Evarts," Tom assured him
grimly. "I'll hold you responsible."

"I won't let anything happen, Mr. Reade. And I hope you find Mr. Hazelton
all right."

"He may be up at camp," Tom answered, though in his heart he did not
believe it.

Had Harry escaped whatever danger had menaced him, Tom knew very well that
his chum, after appealing for help, would by some means have signaled his
subsequent safety.

However, Tom started toward camp at a run. He was wholly mystified. The
search in the neighborhood of the breach in the wall had been continued
until its hopelessness had been fully demonstrated. The search had also
been continued over the water, for a possible clue to the mystery.

Though Tom ran, he felt himself choking, stifling. Despite all his efforts
to cheer himself the young chief engineer felt certain that his chum had
mysteriously met his fate, and that brave, dependable Harry Hazelton was no
more.

Yet how could he have vanished so completely, and what possibly could have
happened to his assailant or assailants?

"It'll be an awful night, until daylight," Tom groaned inwardly, as he
ran. "At daylight, of course, we can make a far better search, especially
over the water. But in the hours that must elapse---! It's going to be a
tough period of waiting!"

Arrived at camp, Tom made straight for his own barracks, letting himself
in with a latch-key as soon as he could control his shaking hand
sufficiently to use the key.

Tom bounded straight for the bed-room of the superintendent, at the rear
of the little building.