ward the north."

"And what does that indicate?" asked Mr. Damon.

"That we should have begun our search some distance north of the point
where we actually did begin," answered Tom.

"How far north?" the eccentric man wanted to know.

"That's just what we have yet to ascertain," the young inventor
replied. "So far our conclusions have been arrived at merely from
surface data. Now we've got to go below."

"And play with bits of cork there?" asked Mr. Damon.

"No, we'll have to use something heavier than cork," Tom said. "We'll
probably use weights, and see how far they move along the bottom in a
given time. But we have established one thing, and I begin to have
hopes now that we may locate the Pandora."

The remainder of the day was spent in various ways aboard the
submarine, which continued to float idly on the waves.

It was toward evening, when the red, setting sun gave promise of a fair
day on the morrow that the submarine's deck lookout approached Tom,
and, waiting until he had the attention of the young inventor, reported:

"There is a smudge of smoke dead astern, sir."

"Is there?" exclaimed Tom. "Let me have the glasses."

He took them from the lookout and made a long and careful study of the
slight, black smudge which was low down on the horizon.

"A steamer," decided Tom, "and coming on fast. We'll go below!" he
added. "Please make ready," he said to the officer in charge.

"What's up, Tom?" asked Ned, as his chum gathered up the papers on
which he had been figuring on an improvised table set under an awning
on deck.

"Some craft is coming, and I'd just as soon she wouldn't sight us," was
the answer.

"You mean she might interfere with our search for the treasure-ship?"

"Not exactly. But she might want to start a search on her own account,
and there's no use of giving our presence away, or letting them guess
at what might be right conclusions as to the location of the Pandora."

"But, Tom, no one knows of the wreck! At least, no one is supposed to
but our party and--"

"Hardley. Exactly!" exclaimed Tom, as he saw his chum about to utter
the name.

"And you think he is coming?"

"I shouldn't be a bit surprised. Anyhow, it's just as easy for us to
submerge and let them do their own guessing. I was going down soon,
anyhow, and another hour won't make any difference. Here, take a look,
if you like."

Ned peered through the glasses, but his eyes not being trained in sea
interpretation,