"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.