“Mutiny, by Jove!” murmured the Naval officer.  He did not speak excitedly, but with a certain grim dryness.  “Catch up with them as soon as you can, Captain Benson.”

“There they go, heading away from us,” muttered Captain Jack.

“From her present performance she doesn’t look to be over a fourteen-knot boat,” declared Ennerling.  “You won’t be long in running alongside.”

“What do you make out, sir?”

“A white-haired old man, in a yachting suit, and another man in white duck.  They are aft, and both appear to be holding pistols.  There are two women, one middle-aged, I should say, and the other barely more than a girl.  Excellent glasses, these, Benson.”

“Can you make out any mutineers?”

“There are some men, pressing back astern, yet seemingly not wholly liking to risk revolver fire,” went on Commander Ennerling.  “I don’t believe I can make out all the mutineers, from this point of view.”

“What shall we do, sir, when we get alongside?”

“Quell the mutiny,” retorted Commander Ennerling, with emphasis.  “It’s the one choice a Naval officer has in a case of this sort.  Briscoe!  McCrea!”

The two junior officers came hastily up the spiral stairway.  Commander Ennerling told them as rapidly as he could what had happened.

“There’s something wholly wrong on that yacht,” he wound up, “and we’ve got to get alongside and look into it.”

“Want to get out on the platform deck?” inquired Captain Jack.

“Yes, by all means.”

More of the water was expelled from the tanks until the platform deck was two feet above the surface.  Then the manhole was opened, and an interested crowd hurried out on deck.  Only Eph remained below, he, to his disgust, being sent to the motor.

Jack Benson now stood at the deck wheel, while the others gathered at the rail to watch the progress of the pursuit.

Even as they looked, the older man aft on the yacht fired his revolver twice, aiming forward.  The flashes could be distinctly made out, though the reports of the weapon were borne away by the breeze.

“Have either of you gentlemen a revolver?” demanded Commander Ennerling of his subordinate officers.

Neither of them had.  Nor had any of the submarine’s own people.

“Hm!” muttered the commander, grimacing.  “This is a fine Naval outfit to lay alongside of a craft that has a mutiny aboard!”

“Do you want to hail, or try to board the yacht?” inquired Jacob Farnum.

“I think we’d better run alongside and hail that crowd,” answered Commander Ennerling.  “Yet, if it comes to it, we’ll have board!”

Three shots flashed out, amidships, on the yacht, showing that the fire was directed towards the stern.  Two shots from the two men aft replied.  No one appeared to have been hit.

“We’ll have to fight if we’re to be of any use,” muttered Ennerling.  “With our fists, too, confound the luck!”