the line of the
ramparts was soundly concentrated in strong points, equipped with
steam guns and mostly armed with thermit-throwers as well. From the
center of the city there came only a vast, unorganized tumult of
battle and death.

Then a huge winged thing came soaring down past Tommy's tower. It
landed with a crash on the roofs below, spilling its men like ants.
Tommy strained his eyes. There was a billowing outburst of steam from
the tower where Denham had been working the night before. A big flier
burst into the weird bright flame of the thermit fluid. It fell,
splitting apart as it dropped. Again the billowing steam. No
result--but beyond the city walls showed a flash of thermit flame.

"Denham!" muttered Tommy. "He's got a steam cannon; he's shooting
shells loaded with thermit! They smash when they hit. Good!"

He dispatched a man with orders, but a messenger was panting his way
up as the runner left. He thrust a scribbled bit of paper into Tommy's
hand.

"I'm trying to bring down the ship that's controlling the
Death Mist. I'll shell those devils in the middle of town as
soon as our controls can handle the Mist.

Denham."

Tommy began to snap out his commands. He raced downward toward the
street. Men seemed to spring up like magic about him. A ship with one
wing aflame was tottering in mid-air, and another was dropping like a
plummet.

Then Tommy uttered a roar of pure joy. The huge globe of beautiful,
deadly vapor was lifting! Its control-ship was shattered, and men of
the Golden City had found its setting. The Mist rose swiftly in a
single vast globule of varicolored reflections. And the situation in
the center of the city was clear. Two towers were besieged. Dense
masses of the invaders crowded about them, battering at them. Steam
guns opened from their windows. Thermit-throwers shot out flashes of
deadly fire.

Tommy led five hundred men in savage assault, cleaving the mass of
invaders like a wedge. He cut off a hundred men and wiped them out,
while a rear guard poured electric charges into the main body of the
enemy. More men of Yugna came leaping from a dozen doorways and joined
them. Tommy found Smithers by his side, powder-stained and
sweat-streaked.

* * * * *

"Miss Evelyn's all right?" Smithers asked in a great calm.

"She is," growled Tommy. "On the top floor of a tower, with a hundred