natives, too. Some get it, some don’t. It works the same way with Earthmen. You feel like you’re cracking up—and then, suddenly—you go North. Into the swamp. You never come back. That’s the end of you."
"Funny!"
"Sure it is. But—ever heard of the lemmings? Little animals that used to make mass pilgrimages, millions of them. They’d head west till they reached the ocean, and then keep going. Nobody knew the cause of that, either."
"What lies north?"
"Swamp, I suppose. How should I know? We’ve got no facilities for finding out. We can’t fly, and expeditions say there’s nothing there but the usual Venusian hell. I wish—"
*
"Oh-oh!" Vanning sat up, peering into the projector. "Wait a minute, Goodenow. I think—"
"Callahan? No!"
"He’s disguised, but ... Lucky this is a three-dimensional movie. Let’s hear his voice." Vanning touched a button on the box. A low, musical voice said:
"My name is Jerome Bentley, New York City, Earth. I’m an importer, and am on Venus to investigate the possibilities of buying a steady supply of herbs—"
"Yeah," Vanning said tonelessly. "That’s it. Jerome Bentley—nuts! That’s Don Callahan! He’s disguised so well his own mother wouldn’t know him—best make-up artist in the System. But I’ve studied his records till I nearly went blind and deaf. I don’t make mistakes about Callahan any more."
Goodenow blinked. "I’ll be blowed. I’ve seen the man a dozen times, and I’d have sworn ... well! If you’re sure—"
"I’m sure." Vanning referred to the records. "Staying at the Star Palace, eh? Okay, I’ll be pushing off."
"I’ll go with you," the consul offered, and lifted his bulky body from behind the gleaming desk. Together the two men went out into the muggy Venusian day, which was now fading to a slow, blue dusk.
Venus did not revolve; it librated. There was no such thing as sunrise and sunset. But there was a very regular thickening and fading of the eternal cloudbanks that writhed overhead, approximating day and night. Despite the continual frantic disturbance of the atmosphere, the clouds were so thick that it was never possible to see the Sun.
Only the ragged, eye-straining movement of the grayness overhead, and the warm, humid wind that gusted against your sweating skin. And the sulphurous smells that drifted in from the jungle—odors of stagnant water and rottenness and things that grew unhealthily white.
Frontier town, Vanning thought, as he glanced around. Chicago must have looked like this, in the old days, when streets were unpaved and business was the town’s only reason for existence. But Venus Landing would never grow into another Chicago. A few thousand souls, working under terrible handicaps, always fearing the North-Fever that meant death....
Muddy streets, wooden sidewalks already rotting, metal buildings, of two stories at most, long, low hydroponic sheds, a dull, hot apathy that hung over everything—that was Venus Landing. A few natives shuffled past on their snowshoe feet, looking fat and wet, as though made out of wax that had begun to run.
The Star Palace was a down-at-the-heels plastic building, stained and discolored by the damp molds. Goodenow jerked his head at the clerk.
"Where’s Leester?"
"North-Fever," the man said, worrying his lower lip. "This morning ... we couldn’t stop him."
"Oh, hell," the consul said hopelessly, turning to Vanning. "That’s the way it is. Once the fever hits you, you go crazy. Do everything and anything to get away and head north. Leester was a nice kid. He was going back to Earth, next Christmas."
Vanning looked at the clerk. "A man named Jerome Bentley’s staying here."
"He’s somewhere around town. Dunno where."
"Okay," the consul said. "If he comes in, phone my office. But don’t tell him we were asking."
"Yup." The clerk resumed his vague scrutiny of the ceiling. Vanning and Goodenow went out.
*
"Where now?"
"We’ll just amble around. Hi!" The consul hailed a ricksha, drawn by a native—the usual type of vehicle in Venus Landing’s muddy streets. "Hop in, Vanning."
The detective obeyed. His headache was getting worse.
They couldn’t find Callahan. A few men said that they had seen him earlier that day. Someone had glimpsed him on the outskirts of the settlement.
"Heading for the jungle?" Goodenow asked quickly.
"He—yeah. He looked ... very bad."
The consul sucked in his breath. "I wonder. Let’s go out that way, Vanning."
"All right. What do you figure—"
"The fever, maybe," Goodenow grunted. "It strikes fast. Especially to non-natives. If your friend Callahan’s caught North-Fever, he just started walking into the swamp and forgot to stop. You can mark the case closed."
"Not till I get that treaty back," Vanning growled.
Goodenow shook his head doubtfully.
The buildings grew sparser and ceased at the edge of the pale forest. Broad-leafed jungle growths sprang from moist black soil. The ricksha stopped; the native chattered in his own tongue.
"Sure," Goodenow said, tossing him a coin. "Wait here. Zan-t’kshan. " His burly figure lumbered into the translucent twilight of the jungle. Vanning was at his heels.
There were footprints—many of them. The detective ignored them, moving in a straight line away from Venus Landing. Here and there were blazed mola trees, some with buckets hung to collect the dripping sap. The footprints grew fainter. At last only one set remained visible.
"A man. Pretty heavy-set, too. Wearing Earth shoes, not sandals like most of ours. Callahan, probably."
Vanning nodded. "He didn’t come back by this route."
"He didn’t come back," Goodenow said shortly. "This is a one-way trail."
"Well, I’m going after him."
"It’s suicidal. But—I suppose I can’t talk you out of it?"
"You can’t."
"Well, come back to town and I’ll find you an outfit. Supplies and a hack-knife. Maybe I can find some men willing to go with you."
"No," Vanning said. "I don’t want to waste time. I’ll start now." He took a few steps, and was halted by Goodenow’s restraining grip.
"Hold on," the consul said, a new note in his voice. He looked closely into Vanning’s face, and pursed his lips in a soundless whistle.
"You’ve got it," he said. "I should have noticed before."
"Got what?"
"The North-Fever, man! Now listen to me—"
Vanning’s headache suddenly exploded in a fiery burst of white pain, which washed away and was gone, leaving his brain cool and ... different. It was like a—like a cold fever. He found his thoughts were moving with unusual clarity to a certain definite point.... North. Of course he had to go north. That was what had been wrong with him all day. He had been fighting against the urge. Now he realized that it should be obeyed, instead.
He blinked at Goodenow’s heavy, worried face. "I’m all right. No fever. I want to find Callahan, that’s all."
"Like hell it is," the consul said grimly. "I know the symptoms. You’re coming back with me till you’re well."
"No."
Goodenow made a movement as though to pinion Vanning’s hands behind his back. The detective writhed free and sent a short-arm jab to Goodenow’s jaw. There was power behind