and thin as a pancake on a griddle.

"More people live in that mass of concrete," said my uncle, "than in the
whole of America west of the Rocky Mountains." His statement, I have
since learned, fell short of half the truth, but then it seemed
appalling. I fancied the city a giant anthill, and searched with my
glass as if I expected to see the ants swarming out. But no sign of life
was visible upon the monotonous surface of the sand-blanketed roof, and
high above the range of naked vision hung the hawk-like watchers of the
World Patrol.

The lure of unravelled secrets, the ambition for discovery and
exploration stirred my boyish veins. Yes, I would know more of the
strange race, the unknown life that surged beneath that grey blanket of
mystery. But how? For over a century millions of men had felt that same
longing to know. Aviators, landing by accident or intent within the
lines, had either returned with nothing to report, or they had not
returned. Daring journalists, with baskets of carrier pigeons, had on
foggy nights dropped by parachute to the roof of the city; but neither
they nor the birds had brought back a single word of what lay beneath
the armed and armoured roof.

My own resolution was but a boy's dream and I returned to Chicago to
take up my chemical studies.



CHAPTER II

I EXPLORE THE POTASH MINES OF STASSFURT