Nerado heard Costigan's voice, there was no doubt of that. His long neck looped and twisted in Nevian gratification; and although neither side could understand the other, both knew that intelligent speech and hearing were attributes common to the two races. This fact altered markedly the relations between captors and captives. The Nevians admitted among themselves that the strange bipeds might be quite intelligent, after all; and the Terrestrials at once became more hopeful.
"It isn't so bad, if they can talk," Costigan summed up the situation. "We might as well take it easy and make the best of it, particularly since we haven't been able to figure out any possible way of getting away from them. They can talk and hear, and we can learn their language in time. Maybe we can make some kind of a deal with them to take us back to our own system, if we can't make a break."
The Nevians being as eager as the Terrestrials to establish communication, Nerado kept the newly devised frequency changer in constant use. There is no need of describing at length the details of that interchange of languages. Suffice it to say that starting at the very bottom they learned as babies learn, but with the great advantage over babies of possessing fully developed and capable brains. And while the human beings were learning the tongue of Nevia, several of the amphibians (and incidentally Clio Marsden) were learning Triplanetarian; the two officers knowing well that it would be much easier for the Nevians to learn the logically-built common language of the Three Planets than to master the senseless intricacies of English.
In a short time the two parties were able to understand each other after a fashion, by using a weird mixture of both languages. As soon as a few ideas had been exchanged, the Nevian scientists built transformers small enough to be worn collar-like by the Terrestrials, and the captives were allowed to roam at will throughout the great vessel; only the compartment in which was stored the dismembered pirate lifeboat being sealed to them. Thus it was that they were not left long in doubt when another fish-shaped cruiser of the void was revealed upon their lookout plates in the awful emptiness of interstellar space.
"This is our sister-ship going to your Solarian system for a cargo of the iron which is so plentiful there," Nerado explained to his involuntary guests.
"I hope the gang has got the bugs worked out of our super-ship!" Costigan muttered savagely to his companions as Nerado turned away. "If they have, that outfit will get something more than a load of iron when they get there!"
More time passed, during which a blue-white star separated itself from the infinitely distant firmament and began to show a perceptible disk. Larger and larger it grew, becoming bluer and bluer as the flying space-ship approached it, until finally Nevia could be seen, apparently close beside her parent orb.
Heavily laden though the vessel was, such was her power that she was soon dropping vertically downward toward a large lagoon in the middle of the Nevian city. That bit of open water was devoid of life, for this was to be no ordinary landing. Under the terrific power of the beams braking the descent of that unimaginable load of allotropic iron the water seethed and boiled; and instead of floating gracefully upon the surface of the sea, this time the huge ship of space sank like a plummet to the bottom. Having accomplished the delicate feat of docking the vessel safely in the immense cradle prepared for her, Nerado turned to the Tellurians, who, now under guard, had been brought before him.
"While our cargo of iron is being discharged, I am to take you three specimens to the College of Science, where you are to undergo a thorough physical and psychological examination. Follow me."
"Wait a minute!" protested Costigan, with a quick and furtive wink at his companions. "Do you expect us to go through water, and at this frightful depth?"
"Certainly," replied the Nevian, in surprise. "You are air-breathers, of course, but you must be able to swim a little, and this slight depth—but little more than thirty of your meters—will not trouble you."
"You are wrong, twice," declared the Terrestrial, convincingly. "If by 'swimming' you mean propelling yourself in or through the water, we know nothing of it. In water over our heads we drown helplessly in a minute or two, and the pressure at this depth would kill us instantly."
"Well, I could take a lifeboat, of course, but that ..." the Nevian Captain began, doubtfully, but broke off at the sound of a staccato call from his signal panel.
"Captain Nerado, attention!"
"Nerado," he acknowledged into a microphone.
"The Third City is being attacked by the fishes of the greater deeps. They have developed new and powerful mobile fortresses mounting unheard-of weapons and the city reports that it cannot long withstand their attack. They are asking for all possible help. Your vessel not only has vast stores of iron, but also mounts weapons of power. You are requested to proceed to their aid at the earliest possible moment."
Nerado snapped out orders and the liquid iron fell in streams from wide-open ports, forming a vast, red pool in the bottom of the dock. In a short time the great vessel was in equilibrium with the water she displaced, and as soon as she had attained a slight buoyancy the ports snapped shut and Nerado threw on the power.
"Go back to your own quarters and stay there until I send for you," the Nevian directed, and as the Terrestrials obeyed the curt orders the cruiser tore herself from the water and flashed up into the crimson sky.
"What a barefaced liar!" Bradley exclaimed. The three, transformers cut off, were back in the middle room of their suite. "You can outswim an otter, and I happen to know that you came up out of the old DZ83 from a depth of...."
"Maybe I did exaggerate a trifle," Costigan interrupted, "but the more helpless he thinks we are the better for us. And we want to stay out of any of their cities as long as we can, because they may be hard places to get out of. I've got a couple of ideas, but they aren't ripe enough to pick yet.... Wow! How this bird's been traveling! We're there already! If he hits the water going like this, he'll split himself, sure!"
With undiminished velocity they were flashing downward in a long slant toward the beleaguered Third City, and from the flying vessel there was launched toward the city's central lagoon a torpedo. No missile this, but a capsule containing a full ton of allotropic iron, which would be of more use to the Nevian defenders than millions of men. For the Third City was sore pressed indeed. Around it was one unbroken ring of boiling, exploding water—water billowing upward in searing, blinding bursts of super-heated steam, or being hurled bodily in all directions in solid masses by the cataclysmic forces being released by the embattled fishes of the greater deeps. Her outer defenses were already down, and even as the Terrestrials stared in amazement another of the immense hexagonal buildings burst into fragments; its upper structure flying wildly into scrap metal, its lower half subsiding drunkenly below the surface of the boiling sea.
The three Earth-people seized whatever supports were at hand as the Nevian space-ship struck the water with undiminished speed, but the precaution was needless—Nerado knew thoroughly his vessel, its strength and its capabilities. There was a mighty splash, but that was all. The artificial gravity was unchanged by the impact; to the passengers the vessel was still motionless and on even keel as, now a submarine, she snapped around like a very fish and attacked the rear of the nearest fortress.
For fortresses they were; vast structures of green metal, plowing forward implacably upon immense caterpillar treads. And as they crawled they destroyed, and Costigan, exploring the strange submarine with his visiray beam, watched and marveled. For the fortresses were full of water; water artificially cooled and aerated, entirely separate from the boiling flood through which they moved. They were manned by fish some five feet in length. Fish with huge, goggling eyes; fish plentifully equipped with long, armlike tentacles; fish poised before control panels or darting about intent upon their various duties. Fish with brains, waging war!
Nor was their warfare ineffectual. Their heat-rays boiled the water for hundreds of yards before them and their torpedoes were exploding against the Nevian defenses in one appallingly continuous concussion. But most potent of all was a weapon unknown to Triplanetary warfare. From a fortress there would shoot out, with the speed of a meteor, a long, jointed, telescopic rod; tipped with a tiny, brilliantly-shining ball. Whenever that glowing tip encountered any obstacle,