He turned back toward Flint, again, veiling in that impenetrable face of his the slightest hint or expression which might have told Flint that he understood the Billionaire’s vice.  If Flint were Vulture, Waldron was Tiger, indeed.  And so, for a brief moment, these two soulless men of gold and power stood eyeing each other, in silence.

Suddenly Waldron spoke.

“There’s one thing you’ve forgotten to speak of, Flint,” he said.

“And that is?” demanded the other, already calmed by the quick action of the subtle, enslaving drug.

“The effect on the world’s poor—­on the toiling millions!  The results of this innovation, in slum, and slave-quarter, and in the haunts of poverty.  Your talk has all been of the middle and upper classes, and of the benefits accruing to them, from increased oxygen-consumption.  But how about the others?  Every ounce of oxygen you take out of the air, leaves it just so much poorer.  Store thousands of tons of the life-giving gas, in monster tanks, and you vitiate the entire atmosphere.  How about that?  How can even the well-to-do breathe, then, out-doors, to say nothing of the poverty-stricken millions?”

Flint grimaced, showing a glint of his gold tooth—­his substitute for a smile.

“That’s all reckoned for,” he answered.  “I thought I made it quite clear, in our previous talk.  To begin with, we will withdraw the oxygen from the atmosphere so slowly that at first there won’t be any noticeable effect on the out-door air.  For a while, the only thing that will be noticed by the world will be that our gas service, to private residences and institutions, will result in greatly increased comfort and health to the better classes.  And the cost will be so low—­at first, mind you, only at first—­that every family of any means at all can take it.  In fact, Wally, we can afford practically to give away the service, for the first year, until we get our grip firmly fixed on the throat of the world.  Do you get the idea?”

Waldron nodded, as he drew leisurely on his cigar.

“Practical to a degree,” he answered.  “That is, until the poor begin to gasp for breath.  But what then?”

“By the time the outer atmosphere really begins to show the effect of withdrawing a considerable percentage of the oxygen,” Flint answered, “we will have our pocket respirators on the market.  Well-to-do people will as soon think of going out without their shoes, as they will with their respirators.  No, there won’t be any visible tubes or attachments, Wally.  Nothing of that kind.  Only, each person will carry a properly insulated cake of solidified oxygen that will evaporate through the special apparatus and surround him with a normally rich atmosphere.  And—­”

“Yes, but the poor?  The workers?  What of them?”