r separated them from the Transcontinental machine
below. Now they saw through their field glasses that the great plane was
lumbering slowly across the field, gaining momentum as it headed
westward into the breeze. Then it seemed to be barely clearing the great
skyscrapers that towered twenty-four hundred feet into the air, arching
over four or five city blocks. From this height they were toys made of
colored paper, soft colors glistening in the hot noon sunlight, and
around and about them wove lines of flashing, moving helicopters, the
individual lost in the mass of the million or so swiftly moving
machines. Only the higher, steadily moving levels of traffic were
visible to them.

"Just look at that traffic! Thousands and thousands coming back into the
city after going home to lunch--and every day the number of helicopters
is increasing! If it hadn't been for your invention of this machine,
conditions would soon be impossible. The airblast in the cities is
unbearable now, and getting worse all the time. Many machines can't get
enough power to hold themselves up at the middle levels; there is a down
current over one hundred miles an hour at the 400-foot level in downtown
New York. It takes a racer to climb fast there!

"If it were not for gyroscopic stabilizers, they could never live in
that huge airpocket. I have to drive in through there. I'm always afraid
that somebody with an old worn-out bus will have stabilizer failure and
will really smash things." Morey was a skillful pilot, and realized, as
few others did, the dangers of that downward airblast that the countless
whirring blades maintained in a constant roar of air. The office
buildings now had double walls, with thick layers of sound absorbing
materials, to stop the roar of the cyclonic blast that continued almost
unabated twelve hours a day.

"Oh, I don't know about that, Morey," replied Arcot. "This thing has
some drawbacks. Remember that if we had about ten million of these
machines hung in the air of New York City, there would be a noticeable
drop in the temperature. We'd probably have an Arctic climate year in
and year out. You know, though, how unbearably hot it gets in the city
by noon, even on the coldest winter days, due to the heating effect of
the air friction of all those thousands of blades. I have known the
temperature of the air to go up fifty degrees. There probably will have
to be a sort of balance between the two types of machines. It will b