the
white mist spread and spread. But it fell short of the little hillock.

* * * * *

"Quick thinking," said Tommy coolly. "He thought we had this man a
prisoner, and he'd be better off dead. But--"

Their captive was shouting again. His head thrown back, he called
sentence after sentence aloft while the three ships soared back and
forth above their heads, soundless as bats. One of the three rose
steeply and soared away toward the city. Their captive, grinning,
turned and nodded his head satisfiedly. Then he sat down to wait.

Twenty minutes later a monstrous machine with ungainly flapping wings
came heavily over the swamp. It checked and settled with a terrific
flapping and an even more terrific din. Half a dozen armed men waited
warily for the three to approach. The golden weapons lifted alertly as
they drew near. The wounded man explained at some length. His
explanation was dismissed brusquely. A man advanced and held out his
hands for Tommy's weapons.

"I don't like it," growled Tommy, "but we've got to think of Earth. If
you get a chance hide your gun, Evelyn."

He pushed on the safety catches and passed over his guns. The pilot he
had shot down led them onto the fenced-in deck of the monstrous
ornithopter. Machinery roared. The wings began to beat. They were
nearly invisible from the speed of their flapping when the ship lifted
vertically from the ground. It rose straight up for fifty feet, the
motion of the wings changed subtly, and it swept forward.

It swung in a vast half circle and headed back across the marsh for
the Golden City. Five minutes of noisy flight during which the machine
flapped its way higher and higher above the marsh--which seemed more
noisome and horrible still from above--and then the golden towers of
the city were below. Strange and tapering and beautiful, they were. No
single line was perfectly straight, nor was any form ungraceful. These
towers sprang upward in clean-soaring curves toward the sky. Bridges
between them were gossamerlike things that seemed lace spun out in
metal. And as Tommy looked keenly and saw the jungle crowding close
against the city's metal walls, the flapping of the ornithopter's
wings changed again and it seemed to plunge downward like a stone
toward a narrow landing place amid the great city's towering
buildings.

CHAPTER VI

_The Golden City_

The thing that struck Tommy first of all was the scarcity of men in