Ted Wainwright and Bill Witt were speculating on the fate of their chum.

“I hope he made it all right,” sighed Ted after a long period of silence that had followed the discharge of the “human torpedo.”  Gloom pervaded the chamber of steel; every man was at the point of despair.

“He’s a good swimmer; he proved that when he plucked ‘Little Mack’ out of the sea the day we ran afoul of that floating German mine,” countered Bill.  “If we are as near the land as Lieutenant Mcclure thinks we are, then Jack will make it sure as anything.”

Chief interest centered in the wireless room where Sammy Smith was listening at the microphone.  If, perchance, Jack had made the surface and succeeded in arresting the attention of the passing vessel, then the microphones would reveal the approach of the returning ship.

But, as Smith listened intently, the sound of the revolving propeller blades gradually diminished and the commander and crew of the Dewey knew only too well that either Jack had lost his life in the venture or had been unnoticed as he floated in the sea.

“There don’t appear to be anything doing up above,” ventured Mike Mowrey as he glided up alongside the two boys.

“Guess not,” faltered Ted.  “We seem to be right up against it.”

All hope of rescue was abandoned.  For nearly thirty-six hours now the Dewey had remained under water.  Her crew of men, breathing over and over again the same supply of air, were rapidly exhausting the life-sustaining reserves of oxygen.  Little by little the precious stores had been liberated until now very little remained.  Many of the men were coughing asthmatically; several were languishing in a dumb stupor from the fetid air.

Ted could not help turning his attention to the huge ventilator shaft that fed fresh air into the Dewey when she was cruising on the surface.  He remembered well that first undersea dive back home in an American port when he and Jack had discussed the possibilities of ever being lost on the bottom of the sea with the ship’s air supply cut off.  Now he was face to face with that very situation.  The thought chilled his blood and he found it very hard to be brave under the circumstances.

Jean Cartier, his face blanched and his hair ruffled, appeared in the torpedo compartment, the picture of dismay.

“It ees ze veery hard thing to breathe back there,” he gasped, pointing over his shoulder toward the engine room aft.

Almost immediately the boys forward could hear Commander Mcclure giving orders to open the reserve oxygen tanks.  Under the emergency measures adopted living conditions were for the time greatly relieved; but every man aboard knew this relief was but temporary and realized that in twenty-four hours more at the most the supply of oxygen would be entirely exhausted.

The morning wore on to noon and mess was served to a crew of men who cared little to eat.  Grim disaster stared them in the face.