f other
radiations--some of which evidently speed up evolution. Anyway, we may
be able to find friends here more quickly if we aid one side or the
other in the very lively battle going on there. Before we go any
further, what's our decision?"

"I think it is a fine idea," said Fuller. "But which side are we to
aid--and what are the sides? We haven't even seen them yet. Let's go
nearer and take a good look."

"Yes--but are we going to join either side after looking?"

"Oh, that's unanimous!" said Wade, excitedly.

The invisible ship darted forward. They sped past the barrier of low
hills, and were again high above a broad plain. With a startled gasp,
Arcot cut their speed. There, floating high in the air, above a
magnificent city, was a machine such as no man had ever before seen! It
was a titanic airplane--monstrous, gargantuan, and every other word that
denoted immensity. Fully three-quarters of a mile the huge metal wings
stretched out in the dull light of the cloudy Venerian day; a machine
that seemed to dwarf even the vast city beneath it. The roar of its
mighty propellers was a rumbling thunder to the men in the _Solarite_.
From it came the flashing bursts of flame.

On closer inspection, the watchers saw what seemed to be a swarm of tiny
gnats flying about the mighty plane. They appeared to be attacking the
giant as vainly as gnats might attack an eagle, for they could not
damage the giant machine. The flashing bombs burst in blasts of yellow
flame as harmlessly as so many firecrackers.

All that mighty plane was covered with heavy metal plates, fully ten
inches thick, and of metal so tough that when the powerful bombs hit it
they made no impression, though they blasted tremendous craters in the
soil below. From it poured a steady stream of bombs that burst with a
great flash of heat and light, and in an instant the tiny planes they
struck streaked down as incandescent masses of metal.

Yet the giant seemed unable to approach the city--or was it defending
it? No, for it was from the city that the vainly courageous little ships
poured out. But certainly it was not these ships that kept the titanic
battleship of the air at bay!

Tensely the men watched the uneven conflict. The rain of bombs
continued, though all fell short of the city. But slowly around the
metropolis there appeared an area of flaring, molten lava, and steadily
this moved toward the beautiful buildings. Suddenly the battleship
turned towar