d.

Off on the seaward horizon an indefinite haze was soon observable. To
the untrained eye it didn't look like much. Though Mr. Seaton spoke of
it, he didn't appear much concerned.

"It'll be a pity to bother him until the time comes when he throbs
with worry," thought Captain Tom Halstead, sympathetically. "But if
that low-hanging haze doesn't spell t-r-o-u-b-l-e, then I've been
raised among a different breed of sea fogs!"

The crashing of sparks over the spark-gap had ceased for the present,
and Joe, reporting that there was no wireless craft within reach of
his limited aerials, was on deck once more, waiting until the time
should come around for another trial.

Hank had gone below to start the motors, connecting them with the
dynamo, to renew the supply of electrical "juice" in the storage
batteries, which was running low, as proved by the last message sent.

The chug-chug of the twin motors was heard over on the seventy-footer,
and soon an unknown man, his cap pulled well down over his eyes,
appeared at the stern of the Drab. He took a long, keen look at the
"Restless."

"He's wondering if we're going to hoist the mud-hook," smiled Tom.

"And hoping that we are," grinned Joe. "Oh, but we must be an eyesore
to those wistful scoundrels!"

Powell Seaton now spent most of his time gazing at the line of haze,
which, by degrees, was growing bigger and coming nearer.

"Captain Halstead," he faltered, "I'm beginning to feel certain that
you're a prophet."

"Or a Jonah?" laughed Tom, though it was not a very cheerful sort of
laugh.

"No, no, no!" cried the charter-man, earnestly. "Never that! The
little luck that I've had in these trying days has all come through
you youngsters. Without you I'd have been flat on my back in the
fearful game that I'm playing with such desperate hopefulness against
hope. But I see our fog is coming in as a sure thing. If it envelops
us, what can you do with regard to that drab-tinted sea-monster over
yonder?"

"It depends upon the depth and duration of the fog, sir," Halstead
answered. "We have our motors going. At the first strong sign of our
getting hemmed in by it we'll lift our mud-hook [the anchor] and move
in closer. If the fog isn't too thick we may be able to take up a
position where we can at least observe her dimly. If she starts to
pull out into a fog-bank, we'll follow at her heels, keeping as close
as necessary to keep the Drab's stern flag-pole in sight. We won't