nd slid under.

On the northbound leg they had trouble keeping the boards down because
of the tendency of the lead rope to pull the front of the boards up, but
by crawling far forward, they managed.

They were deeper than they had ever gone before, but Rick felt no
sensation of fright or strangeness. It was a green world, not dark but
yet not bright. The light was subdued, filtered by the fathoms of water.
The bottom was mostly clear sand, dotted now and then by patches of
growth. There did not seem to be many fish, or perhaps their eyes were
not adjusted to the subdued light. Scotty was close to the reef on the
northbound leg, while Rick was about twenty feet farther out.

For long moments there was only the sensation of rushing through the
water, the distant throb of the engines, and the sound of their own
bubbles. Then, ahead, Rick saw a mass of growth and tilted his board
upward just in time to clear it.

Scotty hooted once, then again. Rick turned in time to see his pal's
board leap ahead, free of Scotty's weight. Sudden fear gripped him. Had
Scotty been caught? Instantly he released his own board and saw it scoot
for the surface. He reversed his course and swam rapidly back.

The obstruction he had cleared was dead ahead. And there were fish! So
many that they seemed like a swarm of flies around it. The biggest was
not more than five inches long. Then he saw Scotty. His friend was
fastening the float line to a projection!

Rick's heart leaped. What he thought was a rock formation on the sea
floor was the wreck of a ship! Scotty had recognized it and dropped off.
The _Maiden Hand_? He hooted and Scotty looked up. The other boy shook
his head.

It wasn't the _Maiden Hand_, then. But how did Scotty know? In a moment,
when he joined the other boy, he saw the curling edges of steel plate.
This was a steel ship, then, and not a very large one at that. He
estimated its length as not more than a hundred feet. Still, it was a
wreck--their first. There, at twenty fathoms, he and Scotty shook hands
solemnly while the tiny fish swam around them like curious gnats.

Scotty finished tying his line and unwound it from the wooden spool. The
float rose upward and vanished far overhead. They heard the throb of the
returning boat, and Rick hooted twice, the signal to surface. Scotty
nodded, and they went up, slowly, careful to breathe naturally and not
to overtake their small bubbles, as doctrine dictated. In a moment Rick