“Be very sure I won’t, sir,” replied Jack, earnestly.  “And we’ll be ready to start at the stroke of five.  But I’ve been thinking, sir, and there’s one question I want to ask.  Does Grant Andrews go with us?

“No,” replied Mr. Farnum, dropping his voice.  “I need Grant for other work.  The first hint I get at Cape Adamson that we have a winner in the way of a submarine, I’m going wire Andrews to start laying the keel for another.  He has his orders, and knows what may be coming.”

“We really ought to have a fourth member of the crew, sir,” explained Captain Jack, “if we’re to keep watch and perhaps run on long trips.”

“I’ll see if I can get someone who’ll be any good to us,” nodded Mr. Farnum, seriously.  Then he and the inventor went ashore, leaving the young captain to the leisurely task of fitting for sea service.

The news that the “Pollard” was going to attend the naval manoeuvres at Cape Adamson soon became noised about Dunhaven, for Mr. Farnum saw no reason for holding back the nature of his orders from Washington.  It was not long before groups of people gathered on the shore, on either side of the boat yard, to gaze with increased interest at the grim, mysterious looking submarine.

Before one o’clock Mr. Farnum put off in the tender with a stranger, a swarthy, stalwart, almost gigantic looking man of about forty.

“I’ve got you just the man you want, Captain,” called the builder, joyously, as he came aboard.  “Captain, this is Bill Henderson, late boatswain’s mate, of the United States Navy.  He knows all about our line of work, for his papers show that he has served aboard various submarine torpedo craft belonging to the Government.  He’s a crack helmsman, a navigator, and knows all about our kind of machinery.”

During this introduction Henderson had saluted and scraped.  He now stood at attention.

“The youngest captain I’ve ever sailed under, sir,” he said to Jack.  “But I’m satisfied you know the business, or Mr. Farnum wouldn’t have given you the berth.  At your orders, sir.”

After Mr. Farnum had returned to shore Benson put his new hand through a searching quiz.  If there was anything Boatswain’s Mate Henderson did not know about submarine boat work, then the young captain was not able to find out what it was.

“Bill Henderson ought to be captain, not I,” whispered Jack to his chum.

“If Mr. Farnum didn’t find that out for himself,” replied Hal, dryly, “don’t tell him.”

“This man Henderson is certainly a jewel for us,” murmured Captain Jack.

At the moment the three boys were standing on the platform deck, while Henderson was stowing his limited baggage away below.

“Now, Cap, take this from me,” muttered Eph, with the air of a wiseacre.  “When a man seems a crackerjack at anything, and doesn’t have as good a position as you think he ought to have, keep your eye on him.”