Stone's office, he reviewed what he had learned on those trips.

Jupiter, as he knew it, was a vast globe of vague horror and sharp contrasts.

Distant from the sun as it was, it received little solar heat. But, with so great a mass, it had cooled off much more slowly than any of the other planets known, and had immense internal heat. This meant that the air—which closely approximated Earth's air in density—was cool a few hundred yards up from the surface of the planet, and dankly hot close to the ground. The result, as the cold air constantly sank into the warm, was a thick steamy blanket of fog that covered everything perpetually.

Because of the recent cooling, life was not far advanced on Jupiter. Too short a time ago the sphere had been but a blazing mass. Tropical marshes prevailed, crisscrossed by mighty rivers at warmer than blood heat. Giant, hideous fernlike growths crowded one another in an everlasting jungle. And among the distorted trees, from the blanket of soft white fog that hid all from sight, could be heard constantly an ear-splitting chorus of screams and bellows and whistling snarls. It made the blood run cold just to listen—and to speculate on what gigantic but tiny-brained monsters made them.

Now and then, when Brand had been flying dangerously low over the surface, a wind had risen strong enough to dispel the fog banks for an instant; and he had caught a flash of Jovian life. Just a flash, for example, of a monstrous lizard-like thing too great to support its own bulk: or a creature all neck and tail, with ridges of scale on its armored hide and a small serpentine head weaving back and forth among the jungle growths.

ccasionally he had landed—always staying close to the space ship, for Jupiter's gravity made movement a slow and laborious process, and he didn't want to be caught too far from security. At such times he might hear a crashing and splashing and see a reptilian head loom gigantically at him through the fog. Then he would discharge the deadly explosive gun which was Earth's latest weapon, and the creature would crash to the ground. The chorus of hissings and bellowings would increase as he hastened slowly and laboriously back to the ship, indicating that other unseen monsters of the steamy jungle had flocked to tear the dead giant to pieces and bolt it down.

Oh, Jupiter was a nice planet! mused Brand. A sweet place—if one happened to be a two-hundred-foot snake or something!

He had always thought the entire globe was in that new, raw, marshy state. But he had worked only in one comparatively small area of the northern hemisphere; had never been within thirty thousand miles of the red spot. What might lie in that ominous crimson patch, he could not even guess. However, he reflected, he was soon to find out, though he might never live to tell about it.

Shrugging his shoulders, he turned into the fifty story building in which was his modest apartment. There he found, written by the automatic stylus on his radio pad, the message: "Be with you at seven o'clock. Best regards, and I hope you strangle. Dex Harlow."

ex Harlow was a six-foot Senior Lieutenant who had been on many an out-of-the-way exploratory trip. Like Brand he was just under thirty and perpetually thirsting for the bizarre in life. He was a walking document of planetary activity. He was still baked a brick red from a trip to Mercury a year before: he had a scar on his forehead, the result of jumping forty feet one day on the moon when he'd meant to jump only twenty; he was minus a finger which had been irreparably frost-bitten on Mars; and he had a crumpled nose that was the outcome of a brush with a ten-foot bandit on Venus who'd tried to kill him for his explosive gun and supply of glass, dyite-containing cartridges.

He clutched Brand's fingers in a bone-mangling grip, and threw his hat into a far corner.

"You're a fine friend!" he growled cheerfully. "Here I'm having a first rate time for myself, swimming and planing along the Riviera, with two more weeks leave ahead of me—and I get a call from the Old Man to report to you. What excuse have you for your crime?"

"A junket to Jupiter," said Brand. "Would you call that a good excuse?"

"Jupiter!" exclaimed Dex. "Wouldn't you know it? Of course you'd have to pick a spot four hundred million miles away from all that grand swimming I was having!"

"Would you like to go back on leave, and have me choose someone else?" inquired Brand solemnly.

"Well, no," said Dex hastily. "Now that I'm here, I suppose I might as well go through with it."

Brand laughed. "Try and get you out of it! I know your attitude toward a real jaunt. And it's a real jaunt we've got ahead of us, too, old boy. We're going to the red spot. Immediately."

ex's sandy eyebrows shot up. "The red spot! That's where Coblenz and Heiroy were lost!"

"And Journeyman," added Brand. "He's the latest victim of whatever's in the hell-hole."

Dex whistled. "Journeyman too! Well, all I've got to say is that whatever's there must be strong medicine. Journeyman was a damn fine man, and as brave as they come. Have you any idea what it's all about?"

"Not an idea. Nobody has. We're to go and find out—if we can. Are you all ready?"

"All ready," said Dex.

"So am I. We'll start at eleven o'clock in one of the Old Man's best cruisers. Meanwhile, we might as well go and hunt up a dinner somewhere, to fortify us against the synthetic pork chops and bread we'll be swallowing for the next fortnight."

They went out; and at ten minutes of eleven reported at the great space ship hangars north of New York, with their luggage, a conspicuous item of which was a chess board to help while away the long, long days of spacial travel. Brand then paused a little while for a final check-up on directions.

They clambered into the tiny control room and shut the hermetically sealed trap-door. Brand threw the control switch and precisely at eleven o'clock the conical shell of metal shot heavenward, gathering such speed that it was soon invisible to human eyes. He set their course toward the blazing speck that was Jupiter, four hundred million miles away; and then reported their start by radio to Commander Stone's night operator.

The investigatory expedition to the ominous red spot of the giant of the solar system was on.

CHAPTER II

The Pipe-like Men

rand began to slacken speed on the morning of the thirteenth day (morning, of course, being a technical term: there are no horizons in space for the sun to rise over). Jupiter was still an immense distance off; but it took a great while to slow the momentum of the space ship, which, in the frictionless emptiness of space, had been traveling faster and faster for nearly three hundred hours.

Behind them was the distant ball of sun, so far off that it looked no larger than a red-hot penny. Before them was the gigantic disk of Jupiter, given a white tinge by the perpetual fog blankets, its outlines softened by its thick layer of atmosphere and cloud banks. Two of its nine satellites were in sight at the moment, with a third edging over the western rim.

"Makes you think you're drunk and seeing triple, doesn't it?" commented Dex, who was staring out the thick glass panel beside Brand.