Governor Nikkia was like the majority of the First Race. Although he was not large of stature, his powerful muscles bulged impressively under his clothing. The two relatively slender Earthmen, naked save for their trunks, looked almost ridiculously puny. Lents' portly figure was more impressive, but the big scientist had all he could do to carry his weight, so uncomfortably augmented by Jupiter's great mass. The unaccustomed thickness of the atmosphere, too, made the Earthmen uncomfortable. The heat was excessive, for although the outer cloud masses had been determined by photometric telescopic examination to be near the freezing point of hydrogen, Jupiter's enormous store of internal heat made its surface temperature average around 100 degrees Fahrenheit. The humidity was high, and the explorers from Earth were distressed.

Nikkia was a good host, however. He ordered out one of the government cars, luxurious conveyances supported by gravity repulsion buttons, and personally accompanied his guests on a tour of inspection through the murky fog. They rode interminably over wet, domed roofs, down through gloomy arcades. Thunder rumbled incessantly, and occasionally there came a lurid glow of lightning.

For a city of Rubio's extent, they saw very few people. Occasionally they saw the erect, confident figure of a member of the First Race, tending some mighty engine whose purpose they could only guess. The inhabitants preferred to stay indoors, if they could not afford to dally in The Pleasure Bubble.

Nikkia listened with interest to the voyagers' account of their journey through space. But he did not respond with much enthusiasm to the suggestion that interplanetary commerce be resumed.

"We are comfortable," he said good-naturedly. "Besides, I'm not sure that the Mugs could build ships suitable for such long trips. They're getting lazier every day!" He shook his head regretfully.

"What do you expect?" Sine blurted. "You treat them like slaves, ruin their lives, and then you're surprised because they lack ambition!"

Nikkia looked at him in mild astonishment. "But they have to be kept in their place! If we gave them free hand they'd soon run us out. Why, not fifty years ago——"

He told again of that uprising that had resulted in the breaking of the Second Race's pretension. "We have to control 'em," he ended smugly.

The Earthmen were baffled by the bland indifference of the Jovians to their mother planet. They met many of the First Race in the next few days, but none seemed interested but the so-called Mugs, the Second Race, and their interest was wistful akin to nostalgia.

But the three scientists were to learn that the First Race were good fighting men, regardless of their short-comings in other lines.

The glowing "teardrops" appeared a little over a week later. They were so called because of their shape, but the Jovians knew as little about their nature as did their guests. They appeared early one murky morning, as Kass, Sine and Lents sat at breakfast with Governor Nikkia. The servants, comely, characterless specimens of the Second Race who held themselves snobbishly above their fellows, came panic-stricken;

"Your Supremacy!" called one, making a low obeisance. "There are strange lights hanging over the palace!"

Nikkia brushed the slight fellow aside, dashed up a stairway to a terrace on the roof, closely followed by his guests. In a few moments they were all soaked by the warm downpour as they stood on the terrace, like an island in a sea of brown fog.

There were three of them, roughly egg-shaped, but with an elongated tail. More like tadpoles, save that the tail was rigid and emitted a fiery streak. Obviously they were propelled by a new adaptation of the old rocket principle. They swam back and forth slowly, as if questing for something, leisurely selecting their victims. The strangest thing about them, however, was the light. A brilliant red, almost pink, like the glow of a neon tube, it penetrated the fog. Its pulsations even penetrated brain and body, so that the watchers became unpleasantly conscious of it.

Nikkia, watching tensely, turned suddenly on his guests;

"Damned funny! Barely you show up, and now this! I don't like it. Are they from the Earth?"

Lents swelled in slow and ponderous anger.

"Do you think, sir, that we are of the sort to abuse your hospitality by spying on you? We don't know any more about those things than you do!"

"Damned funny!" Nikkia repeated to himself. "Wonder if there's any of them left?"

"Your Supremacy!" a servant interrupted. "Call from the war office!" He was carrying a drum-like contrivance, carried on a stand, and set it down in front of the governor.

"Well?" Nikkia snapped impatiently.

The screen which formed the drumhead glowed into life. A Jovian officer, looking exceedingly efficient and warlike in his armor uniform, stood at salute, which Nikkia returned impatiently.

"Who are those flyers, Sonta?" the governor snapped.

"I don't know, Your Supremacy," the officer growled. "They fail to answer our challenge, and none of the men have seen anything like them."

"Then why don't you turn the heat on them?"

"We have. Our heat-rays have no effect on them. That pinkish light is a reflector wave of some sort. Several of our beam projectors were burnt up by the kick-back."

"Ram 'em then! Ram 'em! Sacred Ganymede! Is our Defense Service degenerating into a crew of Mugs?"

The officer's image on the screen was seen to flush, to draw itself up resentfully.

"We have sent ships up to ram them, Your Supremacy. Three of them have been destroyed."

"I was watching. I saw nothing."

"The visibility is worse than usual. They are half a mile high. Our own ships are invisible at a hundred yards. It's that cursed light."

Nikkia shut him off peremptorily.

"Never mind the conversation, Sonta. Get out every available defense craft. Box those teardrops. Ram them. Destroy them—I don't care how!"

The screen was suddenly dark, and Nikkia gazed angrily up at the mysterious glowing craft overhead. So far they had done no damage except to the city's fighting ships.

"Listen!" Sine exclaimed. His body glistened like wet bronze as he stood in the half darkness and strained to catch some sound over the steady patter of rain. "Lents, quit puffing!"

From high overhead, some sounds were coming to them. A steady, droning rush, like the sustained exhaust of rockets. That must be from the visitors, for the official ships were equipped with the gravity buttons. Now and again one of the glowing teardrops would be thrown violently from its course, evidently the effect of impingement of the gravity beam. But not one was disabled. The defense ships were not faring so well. Every little while there would be a fog-muffled crash as one of them crashed, throwing a stone roof into the street. But none fell near the governor's palace.

It was uncanny. No sound save that low, sibilant roar, and an occasional crash out there somewhere in the darkness. The mysterious attacking ships so plainly visible and so immune, and the defensive fighting craft, flying in silence and invisibility—crashing anonymously.

Nikkia had dropped his air of assurance and calm superiority. He was frankly worried, and still a little suspicious of his guests. This attack—it did seem rather a coincidence. What would Sonta have to report now?

He twisted a dial on the side of the communication drum. A junior officer appeared on the screen.

"What the devil?" the governor exploded. "Where is Sonta? I'll have him broken for this! Lieutenant, call Colonel Sonta at once!"

"Your Supremacy," the lieutenant said respectfully, "Colonel Sonta went up in one of the guard ships, and it has been reported crashed south of the catalyst plants."

For a second Nikkia stared at the screen, then snapped the switch wordlessly.

The attackers seemed to have broken down the capital's defenses. Here and there, through the thick, greasy fog, a lurid red glow would take life. That was the fog-diffused reflection of a heat-beam, probing the sky for the "teardrops." After a little while the glow would flare up and as suddenly die down, followed by utter blackness. Another heat-beam out of commission.

Nikkia was frantically polling all of the city's defense commanders. They reported failure with monotonous regularity. The electronic barrage wall around the city had been passed easily—the equipment wrecked. A proton bombardment had yielded exactly nothing—He snapped the switch, peered eagerly at the mist curtain overhead—there was a series of heavy concussions. The glowing visitors were being bombarded from above. The screen glowed again....

"... but the bombs are all detonated long before they get in effective range of...."

Close by a vague shape—a darker shadow in the muggy air, suddenly materialized. It was falling swiftly—a familiar cylindrical shape with rounded ends—one of the Jovian guard ships. It struck scarcely a hundred yards from the palace—struck with a jarring burst of sound like rending metal. Then utter silence again, and darkness. No cry of wounded man. No man could survive that fall and live.

"Some kind of emanation—shields them from all known attack—" Nikkia swore monotonously and regularly.

The glowing ships now settled down to the real purpose of their attack. They began to course back and forth across the city, methodically. Like burning meteors they disappeared over the horizon, to the city's farthest suburbs, back again, as if over a measured and marked course.

And like burning, melting meteorites, they shed trails of sparks, blazing liquid. Wherever these fiery drops landed there ensued immediately a dry crackling, followed by the rattle of falling masonry. As none of the buildings were inflammable, there was no danger of fire. But wherever this incendiary trail fell, stone cracked and crumbled.

"They are destroying us! Forty million people live here in Rubio. They will kill us all, women and children too!"

"Who are they?" Sine asked suddenly.

Nikkia looked at him bleakly. "Who? Why, the Mugs, of course! Those we banished. Those we thought we wiped out."

"Oh, yeh." Sine's intonation was very dry. "They're giving you a dose of your own medicine."

Nikkia did not reply. As if he apprehended, too late, that his statement might have sounded like a plea for help, he shrugged his massive shoulders with elaborate indifference, saying;

"I and my wives are not afraid to die!"

The Earthmen could no longer watch this ruthless destruction, however, regardless of the provocation.

"You say that pink light is a protection against every known mode of attack?" Sine asked, turning sharply to the governor.

"Yes. And that's sufficient, isn't it?"

"Is it proof against this?" Sine jerked the little tube out of its clip, directed it against a stone parapet that loomed grotesquely through the fog. A brilliant white beam leaped forth, cutting the fog like a bar of platinum. Then there was darkness, and the governor, examining the parapet, noted with growing hope that a stone pillar, a foot in diameter, had been cut off smoothly, cleanly.

"The disintegrating ray!" he murmured. "I have read of that, in fiction. But here! Here it is!"

Suddenly he was all energy.

"Will you use this weapon against our enemies? I assure you that you will be well rewarded. As much eka-iodine as your ship will carry! My own ship is here, in the courtyard. It is swift, and powerful. You have already learned the controls. Take it. Bring down those murderers!"

The fiery meteor was coming toward them again, planting a swath of death a hundred yards wide. There was really only one answer possible. The terrestrial scientists, having come on a mission of peace and discovery, stepped forward in unison.

"Give me the activator key!" Sine said crisply. "Lents, will you see that the port gaskets are loose? Kass, I'd like to have you take the controls."

"Right! Right!" They ran past the governor of the greatest planet in the solar system, ignoring him, down the broad stairs, through halls of weighty magnificence, and into the rain-sluiced courtyard.

The governor's ship was waiting there. Not very large, but fine. Its polished metal gleamed richly.

"Quick, inside!" Sine threw open the manport valves. They were inside. The gravity buttons glowed with their peculiarly material lavender light, and the ship rose vertically with swift acceleration.

From the sky the death trails left by the invaders were clearly visible through the murk which obscured everything else—a pink, pulsating light. And the three glowing vessels were coming toward them.

"Get above them, Kass!" Sine commanded. "When they pass under I'll let them have it."

Closer and closer they came, those blobs of light. The Earthmen could see nothing but the light—get no hint of their construction. But that there were men inside they never doubted. The glowing ships seemed to swell, to expand monstrously, and their throbbing emanations became more furious. They seemed to hesitate as they were about to pass beneath.

"They see us?" Lents rumbled, pulling at his toga nervously. The cloth was soaked, clinging to his fat body.

"Close enough!" Sine decided, leaning out of a port, disintegrator ray tube in his hand.

At that instant the strange pink light seemed to encompass the whole planet. They were bathed in it. The fog was a sea of baleful pink. Sine stiffened into impotent rigidity. The ray tube fell from his numbed fingers. He felt himself floating, weightless, in a sea of red that smothered him deliciously. And swiftly even that consciousness was succeeded by black oblivion.