He burst into a long, shrill cacchination.  Already his face was scarlet and his mind a whirl.  Though neither man understood the reason, yet the fact remained that one of the last great explosions had ruptured a subterranean check-valve closing the six-inch pipe that was to feed the storage-tanks; and now a swift, huge stream of pure oxygen gas was rushing at tremendous velocity into the vast chamber of steel.

Waldron, his heart leaping as though it would burst his ribs, raised a fist to strike down his insulter; then, with drunken indecision, joined in the maniacal laughter of the staggering old man.

In their ears a strange, wild humming now became audible.  Lights danced before their eyes; their senses reeled, and violent, extravagant ideas surged through their drunken brains.

“Ha!  Ha!  Ha!” rang Waldron’s crazy laughter, echoing the old man’s.  All at once, his cigar broke into flame.  Cursing, he hurled it away, staggering back against the ladder and stood there swaying, clutching it to hold himself from falling.

There he stood, and stared at Flint, with eyes that started from his head, with panting breath and crimson face.

The old man, in a sudden revulsion of terror, was now grovelling along the floor, by one of the massive walls, clawing at the steel with impotent hands and screaming mingled prayers and oaths.  His ravings, horrible to hear, echoed through the great tank, now swiftly filling with gas.

“Help!  Help!” he screamed.  “Save me—­my God—­save me—.  Let me out, let me out!  A million, if you let me out!  A billion—­the whole world!  The world, ha! ha! ha!  Damn it to Hell—­the world, I say!  I’ll give the world to be let out!  It’s mine—­I own it—­all, all mine! Ha!  Dogs!  You would rise up against your master and your God, would you?  But it’s no use—­we’ll beat you yet—­out! out!—­the world—­I own it!  All this plant—­this gas, all mine!  My oxygen—­ah! it chokes me! Help!  Help!—­Swine!  I’ll scourge you yet—­absolute power—­the world—!”

With one final spark of energy, panting, his heart flailing itself to death under the pitiless urge of the oxygen, old Flint sprang up, ran wildly, blindly straight across the steel floor, and, screaming blasphemies like a soul in Hell, dashed into the opposite wall.

He recoiled, staggered, spun round and fell sprawling most horribly—­stone dead.

Waldron, at sight of this awful end, felt an uncontrollable terror sweep over his drunk and maddened senses.  Though all his blood was leaping in his arteries, and his breath coming so fast it choked him, yet a moment’s seeming sanity possessed his reeling brain.

“The door!  The door, up there!” he screamed, with a wild, terrible curse.

Then, turning toward the ladder, in spite of his fat and flabby muscles quivering in terrible spasms, he ran up the long steel structure with a supreme and ape-like agility.