In response to Jack’s order the D-16 leaped ahead faster than before.

“Has he sighted our periscope, sir?” asked Jack.

“No, I do not think so, but for a submarine, she is moving with great speed.”

“But not so fast as we are, sir?”

“I should say not quite. We appear to be gaining a trifle.”

“She must be another surprise the enemy has been waiting to spring on us,” said Jack.

“Undoubtedly; and the only thing that gives us the advantage is that we know about what she can do and she has no idea what we can do; in fact not even that we are here.”

“But she is bound to spot us unless we submerge,” said Jack.

“True,” said Lord Hastings, “but if we submerge she is likely to escape us unless we use our searchlight. I would avoid letting her know we are at least on anything like even terms, if possible.”

“I see, sir,” said Jack. “Then the idea is to get as close as possible without being seen, and the moment we are discovered we are to dive?”