y to pay it, the implacable attackers hurled themselves upon
their objectives.

Here were no feeble spheres of space, commanding only the limited
energies transmitted to their small receptors through the ether. Instead
there were all the offensive and defensive weapons developed by hundreds
of generations of warrior-scientists; wielding all the incalculable
power capable of being produced by the massed generators of a mighty
nation. But for the breach opened in the circle by the irresistible
surprise attack, they would have been invulnerable, and, hampered as
they were by the defenseless ends of what should have been an endless
ring, the hexans took heavy toll.

The heptagons, massive and solidly braced as they were, and anchored by
tractor rays as well, shuddered and trembled throughout their mighty
frames under the impact of fiercely driven pressor beams. Sullenly
radiant green wall-screens flared brighter and brighter as the Vorkulian
absorbers and dissipators, mighty as they were, continued more and more
to overload; for there were being directed against them beams from the
entire remaining circumference of the stronghold. Every deadly frequency
and emanation known to the fiendish hexan intellect, backed by the full
power of the city, was poured out against the invaders in sizzling
shrieking bars, bands, and planes of frenzied incandescence. Nor was
vibratory destruction alone. Armor-piercing projectiles of enormous
size and weight were hurled--diamond-hard, drill-headed projectiles
which clung and bored upon impact. High-explosive shells, canisters of
gas, and the frightful aerial bombs and radio-dirigible torpedoes of
highly scientific war--all were thrown with lavish hand, as fast as
the projectors could be served. But thrust for thrust, ray for ray,
projectile for massive projectile, the Brobdingnagian creations of
the Vorkuls gave back to the hexans.

The material lining of the ghastly moat was the only substance capable
of resisting the action of its contents, and now, that lining destroyed
by the uprooting of the fortress, that corrosive, brilliantly mobile
liquid cascaded down in to the trough and added its hellish contribution
to the furious scene. For whatever that devouring fluid touched flared
into yellow flame, gave off clouds of lurid, strangling vapor, and
disappeared. But through yellow haze, through blasting frequencies,
through clouds of poisonous gas, through rain of metal and through
storm of