yet reach with
any great clearness the point where Harry Hazelton had been fighting for
his life against his strange foe in the black night.

"Keep parallel with the wall, Evarts," Tom ordered, crisply. "Conlon, are
you pushing the engines for all it's worth?"

"Yes, sir," came from the engine-tender. "This old craft isn't good for
quite seven miles' an hour, anyway."

"There! Now I've picked up the part of the wall where there isn't any wall
in sight just now," said Tom, wincing over his own bull. "Hazelton ought
to be just this side of there."

"There's no one near the breach," replied Evarts.

"So I see," Reade admitted, in a tone of worriment. "Oh, well, Harry isn't
such an infant as to be wiped out all in one moment."

"Where is Mr. Hazelton then?" inquired Evarts, as Tom swung the arc of the
searchlight in broad curves.

"Great Scott! I wish I knew!" gasped Reade, his perplexity and his anxiety
growing with every second. "There appears to be no one on top of the
wall."

Evarts ran in within a few feet of the wall, on the shore-side of the
breach.

"Shall I land you there, sir?" questioned the foreman.

"Presently," Tom nodded. "But now, back out a few feet and swing the
boat's nose around so that I can make a search with this light." Evarts
obeyed the order. Despite the smallness of the light, Reade was able to
send the searching beam of light back nearly one-half of the way to shore.
Nowhere was there any human being visible on the wall.

"Harry! Hazelton!" bawled Tom, with all the power in his lungs.

There was no answer.

"Jupiter! You'll have to land me, I reckon," quaked Tom Reade. "Drive
her nose in---gently. I'll be ready to jump."

"Be careful how you _do_ jump," warned Evarts. "It's mighty slippery on
that wall tonight."

Tom poised himself as the boat moved in close. Then he took a light
leap, landing safely.

Here the young chief engineer again brought his pocket flash lamp into
play. Closely he scanned the top of the wall all around where he knew he
had left his chum.

But Harry was nowhere to be seen, nor, on the wet wall, could Tom find
any signs of a scuffle, or any other sign that gave him a clue.

"Evarts, this is mighty mysterious!" groaned the young chief.

"Unless---" hinted the foreman.

"Unless what?"

"Perhaps Mr. Hazelton ran along the walltop to the shore."

"He'd have hailed us, then, in passing, wouldn't he?" choked Tom Reade.
"Besides, I had