After a few minutes the search became listless.  At Hal’s suggestion, made with a wan smile, each even searched through his own baggage.  Pantry and galley were patiently ransacked.

“I’ve heard of such things being lost before, in the simplest way, and defying all search for a long time,” mused Hal, aloud.  “It may be the same with that precious wrench.  But the difference, this time, is that we shan’t be here long to wait for it to turn up unexpectedly.”

Farnum dropped into a seat again, and that started the rest, until all had taken seats.  From one to another, dumb, moody looks were passed.  Each was wonderingly asking himself the same question that none would have thought of framing in words.  How much longer could the air last in a pure enough condition to sustain six lives?

Eph Somers chuckled, absently, then looked up, startled and ashamed.  The others gazed at him, comprehendingly.  Each knew that Eph was thinking how idiotic it was for six human beings to sit, in perfect health, waiting until the soiling of the air about them killed them all.  It was a terrible thought; Eph’s mirth was of the hysterical kind.

Finally, after some minutes had passed, Jack Benson dragged himself to his feet.

He was amazed, at first thought, to find out how every joint and muscle in his body ached.  He felt as weary as though he had been without sleep for a month.

Then he understood.  The dreadful lassitude was caused by the withdrawing of the life-giving oxygen from the air.  The oxygen was still there, but combined with the carbon from lungs and blood to form carbonic acid gas, which, in large quantities, is fatal to life.

When Jack moved about now, feeling, dully, as though a cane on which to lean would be a great boon, the others got to their feet with evident effort and joined in one more despairing search.

This hunt ended as the others had done, only more quickly.  The only places into which they had been able to look for the missing wrench were the same places that had been vainly examined twice before.

This time it seemed to cause pain even to sit down.  How much longer could the torment last, ere death came mercifully to their relief?

“It seems as though I ought to reach out my hand and lay it on the wrench,” muttered Captain Jack Benson, to Henderson, next to whom he found himself sitting.

The former boatswain’s mate smiled a ghastly smile, his eyes glowing bright like coals.  Jack turned, with a shiver, away from the strange glint in the big fellow’s eyes.

“Friends,” said Mr. Farnum, presently, “we may as well realize the whole situation, and agree to face it like men.  We can’t find the wrench.  Wherever it is, we are not going to find it.  The little breathable air that is left us here is not going to last more than a few minutes.  We will not waste any more of that air in getting up to make useless searches.  Let us be as calm as possible.  Perhaps each man had better look down at the floor, and so continue to look.  At the end—­the end!—­let no one, I beg of you, raise his eyes to witness the final sufferings of any comrade.”