"Backing her up, Tom?" asked Ned, in a low voice.

"Trying to," was the answer. "But I'm afraid her nose has gone
in pretty deep. I've reversed the propellers."

For perhaps a minute this vibration continued, showing that the
powerful electric motors were turning over the twin propellers at
the blunt stern of the craft. But she did not change her
position.

With a touch of his hand, and still almost as cool as the
proverbial cucumber (though why they should be cool it is hard to
say), Tom stopped the motors. Once again the craft was quiet, but
now, instead of the occupants being able to see clearly from the
thick, glass windows in the forward cabin, the water showed muddy
and murky in the glare of the underwater searchlight.

"Bless my postage stamps, Tom! what has happened?" exclaimed
Mr. Damon. "Has a giant squid attacked us, as one did some time
ago, and is he roiling up the water?"

"No, it isn't a squid, Mr. Damon," replied the young inventor
easily; "though the water does look as if a squid had spilled a
lot of his ink in it. This is just the effect of mud stirred up
by our propellers. There may be more of it."

Ned looked toward Mr. Hardley to see how he was taking it. The
seeker after gold apparently had good control of his nerves, or
else he was ignorant of what was going on. For he asked, casually
enough: