rts or almost anything in
the way of documents, nothing was come upon that would tell anything.

"Unless the log book was kept in a water-tight case the ink would all
run, once it was wet," Tom said, when they were about ready to give up
their search.

"I suppose so," agreed Ned. "But I would like to know whether she
carried treasure."

However, it was impossible to discover this, and dangerous to look too
far into the interior. So Tom and his party were forced to leave
without discovering the secret of the Blakesly, if she possessed one.

Later, however, when they had returned home, Tom and Ned made a report
of what they had seen, and so cleared up the fate of the vessel. They
learned that she carried no treasure, and they were glad they had not
risked their lives looking for it. What had happened to her crew was
never learned.

They returned to the submarine and told what they had viewed. And
then, with a last look at the wreck, they passed on in their search for
the Pandora.

Several fruitless days followed, and though a careful search was made
in the vicinity of the true location given by Mr. Hardley, nothing was
discovered.

"How long will you keep at it before you give up?" asked Ned one
evening, as they went aloft to replenish the air tanks and charge the
batteries.

"Oh, another week, anyhow. I have a new theory, Ned."

"What's that?"

"Ocean currents. I believe there are powerful currents in these waters,
and that they may have shifted the position of the Pandora
considerably. I'm going to study the currents."

"Good idea!" cried his chum.

And the next day they began observations which were destined to have
surprising results.

CHAPTER XXIII

AN UNDERSEA COLLISION

Under the warm, tropical sun the submarine floated idly on the surface
of the calm sea. She had risen from the depths, her hatches had been
opened, and now the crew, the owner, and his guests were breathing free
air. The men were taking advantage of the period above water to wash
out some of their garments, hanging them on improvised lines stretched
along the deck. For Tom Swift had said he would remain above the
surface all day.

Some slight repairs were necessary to the electric motors, and they
could be made only when the craft was on the open sea. This, too, would
afford a chance to recharge the batteries and repair one of them.

For the time being the search under the sea for the treasure ship
Pandora had been