n the port side, and the captain at the end
of the bridge raised his cap in salute as they passed by.

"Where are we going?" asked Ralph, as he saw the prow pointing to the
south. "Are we going to France?"

"What are those funny things bobbing up there for,--that whole line?"
asked Alfred.

"They are the floats for the torpedo nets," replied the captain. "We are
now on our way to go through the gates, and thus avoid the nets."

"Is that why we are following the torpedo chaser?" asked Ralph.

"Yes, and when once inside the lane, we will change our course and reach
the English base for craft of this kind," said the captain.

The submarine followed the wake of the chaser for fully a half hour,
when, for some reason, that boat stopped. As they neared it they noticed
the sailors and marines aboard on the port side, and intently engaged
in looking forward.

"What's up now, I wonder?" said Alfred, as he opened the door of the
conning tower and stepped on the deck.

"Look at the floats ahead," said the captain.

On investigation two of them were noticed moving back and forth, and
occasionally dipping in an unaccountable manner.

"Look at those fellows with the guns on the deck of the chaser," said
Ralph.

Alfred looked up. He saw the gun crews at their stations, with the
officers in charge of the guns standing at one side in attitudes of
expectancy.

"I know," said Alfred. "They have caught one of them."

"Yes; and they are making the same efforts to get away that we were
engaged in only a few hours ago," said the captain.

The chaser steamed back and forth in a quiet, determined way, the men
never for a moment relaxing their watch.

"What are they trying to do with that funny-looking, big, fat gun on the
side near the front end of the deck?" asked Ralph.

"That is a howitzer," answered the captain.

"What in the world do they want a howitzer for?" asked Alfred.

"To use it on the boat if it should get free from the net," replied the
captain.

"Why don't they use it now?" asked Ralph.

"Because they do not want to destroy the boat unless it is absolutely
necessary," answered the captain.

"But how will they know whether the boat gets away?" asked Alfred.

"By the condition of the floats," answered the captain. "You will notice
that the two floats within range of the submarine's action are being
dragged down. If the floats should be in a normal condition, or float on
their true water line, which you c