On deck Pauline was eagerly questioning an under officer about the
torpedoes, when Summers came up.

"You'll have to come down and see for yourself," he said, overhearing
her.

"First I'll show you the pump room--the most important part of us,"
he was saying as Catin, in the boat's bottom, first caught the sound of
nearing voices.

Catin leaped up the steps from the pump room. He was in the nick of
time. A large locker in the main compartment gave him refuge just as
Pauline and Summers reached the room.

"The pumps are our life-savers," said Summers, as he directed Pauline
down the second ladder. "If they go wrong when we're under water we
can't come up."

"And what do you do then?" asked Pauline innocently.

"Oh, just-stay down."

Catin waited breathless in his hiding place until they returned. "By
heaven, they didn't find it!" he breathed eagerly.

Pauline and Ensign Summers stood at the rail watching the foamy rush of
a fast motor boat, when a hail sounded across the water.

A man was standing up in the motor boat and calling through a
megaphone.

Summers raised his glasses. "Do you know who that is?" he asked
laughingly.

"Of course not. What does he want?"

"It's Harry, and I suspect he wants to take you away from us."

Pauline uttered an exclamation of annoyance.

"Isn't he silly!" she cried, "One would think I was, a baby, the way he
watches me."

Soon the voice of Harry could be plainly distinguished.

"Clear your ship; I am going to sink you," he called.

"Cargo too precious this trip; don't do it," answered Summers.

"Let me take the megaphone," demanded Pauline.

"What do you mean by following us?" she cried.

"I don't trust that sardine can, and I want a regular boat on hand when
you are wrecked."

"I am very angry with you. It looks as if--"

Her words were drowned in Summers' laughter.

"Never mind. I know a way we can escape from him," he said.

"How?"

"Why, sink the boat."

"That will be splendid."

He stepped aside and gave a terse order. Delightedly, Pauline watched
the brief, machine-like movements of the crew trimming the deck.
Summers escorted her back to the conning tower. They descended.
Within a few moments the wonderful craft was buried under the waves.

"There he is--looking for us," laughed Summers, as he made room for
Pauline at the periscope.

Amazed, fascinated, she gazed from what seemed the bottom of the sea
out upon the rolling surface