Thus, when Nevia and her hot, blue sun appeared upon his plates Rodebush was ready for any emergency, and hurled his battleship upon the Nevian with every weapon aflame. But so was Nerado ready; and, unlike her sister-ship, his vessel was manned by scientists well versed in the fundamental theory of the weapons with which they fought. Beams, rods, and lances of energy flamed and flared; planes and pencils cut, slashed, and stabbed; defensive screens glowed redly or flashed suddenly into intensely brilliant, coruscating incandescence. Crimson opacity struggled sullenly against violet curtain of annihilation. Material projectiles and torpedoes were launched under full beam control; only to be exploded harmlessly in mid-space, to be rayed into nothingness, or to disappear innocuously against impenetrable polycyclic screens. Both vessels were equipped completely with iron-driven mechanisms; both were manned by scientists capable of wringing the last possible watt of power from their sources. They were approximately equal in size, and each ship now wielded the theoretical ultimate of power for her mass; therefore neither could harm the other, furiously though each was trying. And more and more nearly they were approaching the red atmosphere of the world of the amphibians. Down into that crimson blanket the two warring space-ships dropped, down toward a city which Costigan recognized as that in which Nerado made his headquarters. "Better hold off a bit," Costigan cautioned. "If I know that bird at all, he's cooking up something," and even as he spoke there shot upward from the city a multitude of flashing balls. The Nevians had mastered the secret of the explosive of the fishes of the greater deeps and were launching it in a veritable storm against the Terrestrial visitor. "Those?" asked Rodebush, calmly. The detonating balls of destruction were literally annihilating even the atmosphere beyond the polycyclic screen, but that barrier was scarcely affected. "No, that," pointing out a hemispherical dome which, redly translucent, surrounded a group of buildings towering high above their neighbors. "Neither those high towers nor those screens were there the last time I was in this town. They're stalling for time down there, that's all those fireballs are for. Good sign, too--maybe they aren't ready for us yet. If not, you'd better take 'em while the taking's good; and if they _are_ ready for us, we'd better get out of here while we're all in one piece." And in fact Nerado had been in touch with the scientists of his city; had been instructing them in the construction of converters and generators of such weight and power that they could crush even the defenses of the super-ship. They were not, however, quite done; the entirely unsuspected possibilities of speed inherent in absolute inertialessness had not entered into Nerado's calculations.