ven if it doesn't there's no cause for
alarm. It would take a man of extraordinary acumen to read _your_
hieroglyphics! Cheer up, Flint. There's really nothing to excite you."

The Billionaire thus adjured, sat down and tried to calm his agitation.

"Rotten luck, eh?" he queried. "But after all, Herzog is likely to find
the book. And even if he doesn't, I guess we're safe enough. The very
boldness of the plan--supposing even that the finder could grasp
it--would put it outside the seeming range of the possible. It's hardly
a hundred to one shot any harm may come of it."

"All right, then, let it go at that," said Waldron. "And now, to
business. Suppose, for example, you've got a perfectly unlimited supply
of oxygen-gas and liquid. How are you going to market it? Just what
details have you worked out?"

Flint pondered a moment, before replying. At last he said:

"Of course you understand, Wally, I can't give you every point. The
whole thing will be an evolution, and new ideas and processes, new uses
and demands will develop as time passes. But in the main, my idea is
this: The big producing stations will steadily extract oxygen from the
atmosphere, thus leaving the air increasingly poorer and less adapted to
sustaining human life.

"I shall store the oxygen in vast tanks, like the ordinary gas-tanks to
be found in every city, only much bigger. These tanks will be fed by
pipe-lines from the central stations, thus."

Flint drew toward him a sheet of his heavily embossed letter-paper, and,
picking up a pencil, began to sketch a rough diagram. Waldron, making no
comment, followed every stroke with keen interest.

"From these tanks," the Billionaire continued, "smaller pipes will
convey the gaseous oxygen to every house taking our service."

"Just like ordinary gas?"

"Precisely. Each room will be fitted with an oxygen jet apparatus,
something like a gas burner, with a safety device to prevent over supply
and avoid the dangers of combustion."

"Combustion?"

"Yes. In pure oxygen, a glowing bit of wire will burst into flame. Your
cigar, there, would catch fire, from the merest spark in its inmost
folds. Too much oxygen in a room not only intoxicates the
occupants--we've already seen _that_ effect--but also develops a great
fire risk. So we shall have to make some provision for that, Wally. It
will be absolutely essential."

"All right. Allowing it's been made, what then?" asked "Tiger," with
extraordinary inter