hat water," Harry went on, in a voice scarcely less disconsolate
than before.

"Of course," nodded Tom. "But the water can hardly be termed a surprise.
We both knew that the Gulf of Mexico is here. We saw it several times
to-day."

The two young men stood on a narrow ledge of stone that jutted out of the
water. This wall of stone was the first, outer or retaining wall of
masonry---the first work of constructing a great breakwater. At high tide,
this ledge was just fourteen inches above the level surface of the Gulf of
Mexico, and at the time of the above conversation it was within twenty
minutes of high tide. The top of this wall of masonry was thirty inches
wide, which made but a narrow footway for the two youths who, on a pitch
black night, were more than half a mile out from shore.

On a pleasant night, for a young man with a steady head, the top of this
breakwater wall did not offer a troublesome footpath. In broad daylight
hundreds of laborers and masons swarmed over it, working side by side, or
on scows and dredges alongside.

"Wait, and I'll show a light," volunteered Tom raising his foot-long
flashlight.

Some seventy-five yards behind them a crawling snake-like figure flattened
itself out on the top of the rock wall.

"Don't show the light just yet," pleaded Harry. "It might only make me
more dizzy."

The flattened figure behind them wriggled noiselessly along.

"Just listen to the water," continued Hazelton. "Tom, I'm half-inclined to
think that the water is roughening."

"I believe it is," agreed Tom.

"Fine time we'll have getting back, if a gale springs up from the
southward," muttered Harry.

"See here, old fellow," interposed Tom vigorously, "you're not up to
concert pitch to-night. Now, I'll tell you what I'll do---first of all,
what _you'll_ do. You sit right down flat on the top of the wall. Then
I'll move on up forward and see what has been happening out there that
should boom shoreward with such a racket. You stay right here, and I'll
be back as soon as I've looked into the face of the mystery."

"What do you take me for?" Harry asked almost fiercely. "A baby? Or a
cold-foot?"

"Nothing like it," answered Tom Reade with reassuring positiveness.
"You're out of sorts, to-night. Your head, or your nerves, or some thing,
has gone back on you, and you walk through this blackness with half a
notion that you're going to walk over a precipice, or drop head-first into
some dang