newly outfitted underseas boat.

"Is there anything wrong?" he asked sharply of Tom. "Why are we in this
position, and why don't we go on out to the open ocean and make a test
at considerable depth? We'll have to go down deeper than this if we
find the Pandora!"

"I suppose so," agreed Tom. "But we have had an accident, and--"

"An accident!" interrupted the gold-seeker, and then Ned saw him turn
pale. "Do you mean to say this is not part of the test?"

"We have run into a mud bank," said Tom. "The steersman must have
become confused, or else, since we last used the submarine, there has
been a shift of the mud banks in this river and one exists where there
was none before. At any rate, we ran our nose deep into it, and here we
are--stuck!"

"Can't we get loose--go up to the surface?" demanded Mr. Hardley.

"I'm trying to bring that about," announced Tom calmly. "So far her
engines haven't been able to pull her loose."

"But Great Scott, man, we can't stay here!" cried the now excited
adventurer. "We'll be drowned like rats in a trap! Let me out! Isn't
there some way? I'll be shot through a torpedo tube, if necessary! I
must get out! I can't stay here to be drowned! I have too much at
stake!"

"Now wait a minute!" calmly advised Tom Swift. "You haven't any more at
stake than the rest of us. None of us wants to be drowned, and there is
only a remote possibility that we shall be. I haven't played all my
cards yet. We can live on this boat for a week, if need be."

"You mean under water as we are now?" asked Mr. Hardley.

"Yes. I always keep the boat provisioned and with plenty of air and
water for a long stay, if need be," replied Tom. "And I did not
overlook the fact that we might have an accident on the trial trip."

"I don't see how you let an accident happen before we even got
started," complained the gold-seeker. "I should think your steersman
would have been more careful."

"He is very careful," explained Tom. "But we have not used the craft
for some time, and, meanwhile, there have been changes in the river,
due, I suppose, to heavy tides. But we may get out of the grip of the
mud bank soon."

"And if we don't, what then?" asked Mr. Hardley.

"Then there is always the torpedo tube," said Tom calmly. "And we are
not very deep down. I think I can save you all."

"I certainly hope so!" was the fretful comment of the adventurer. "I
have too much at stake to be drowned like a rat in a trap! You must