The half-curious eyes of many persons followed these three guests, as the boatbuilder, the inventor and the young submarine captain hastily left the room, followed by the marine lieutenant.

As soon as the admiral’s order had been transmitted to him, the lieutenant in charge of the deck ran to the side gangway, looking for a shore boat.

“Just our confounded luck when we’re in a hurry,” he muttered.  “The only boat I can get is the one that just took Steward Dudley ashore.  See, there it is over yonder, leaving the pier.  It will be here within five minutes.”

“Then I thank our lucky stars,” cried Captain Jack, pointing, “for here comes our own good boat, and we can take it, instanter, if you’ll permit it to come alongside, Lieutenant.

“Certainly,” replied that officer.

Hal Hastings was at the deck wheel, in charge of the boat.  He had just taken a party of sightseeing naval officers back to their ship, and was on his way to the “Pollard’s” moorings.  He caught sight of Benson’s signals, and, slowing down the speed, ran neatly in alongside of the battleship’s gangway platform.

In another twinkling the trio in haste were aboard their own boat.

“Better hurry below,” advised Captain Jack.  “Ship the ventilators and I’ll get inside, close the manhole cover and handle the boat from the conning tower.  Then, if Arthur Miller is watching us from the shore, he’ll think we have officers aboard and are manoeuvering to show off the boat.”

“Arthur Miller?” gasped Hal, in astonishment.

“Down below with you, Hastings,” replied Jacob Farnum, pushing him gently.  “When we’ve time to talk we’ll tell you.”

When, therefore, within sixty seconds, the “Pollard” left the flagship’s side, she was equipped for diving.  A casual observer would have believed she was about to do so with some inspecting party of naval officers.

As he sat in the conning tower Captain Jack steered the most direct course for the pier to which the supposed Miller had gone in the flagship’s shore boat.

In order to do this, the young captain had to cut across the bow of a battleship that had just gotten under way.  There was plenty of searoom for this manoeuvre, so Captain Jack did not hesitate.

Once past the bows of that battleship, however, the young submarine captain’s heart gave a mighty bound.

For, just beyond, was another battleship, also under good headway.  The “Pollard” was between the two.  To go ahead meant a collision with the second battleship, while to reverse speed meant to back into the battleship just passed.

To turn and run between them in either direction might have been feasible, but the battleships, seeing the trouble of the little submarine, were sounding conflicting signals.

It was a situation that had to be met and solved in a second.

Jack Benson’s heart seemed to stop beating; he felt ill, and a cold perspiration beaded his face all at once.