"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 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.