What's going on?"
There was the sound of voices whispering somewhere near the microphone.Finally: "Hello, Mail Ship?"
"Yeah?"
"You're going to have to turn back to Earth, fellow. You can't landhere. It's rough on us, missing a mail trip, but--"
Preston said impatiently, "Why can't I land? What the devil's going ondown there?"
"We've been invaded," the tired voice said. "The colony's beencompletely surrounded by iceworms."
"Iceworms?"
"The local native life," the colonist explained. "They're about thirtyfeet long, a foot wide, and mostly mouth. There's a ring of them about ahundred yards wide surrounding the Dome. They can't get in and we can'tget out--and we can't figure out any possible approach for you."
"Pretty," Preston said. "But why didn't the things bother you while youwere building your Dome?"
"Apparently they have a very long hibernation-cycle. We've only beenhere two years, you know. The iceworms must all have been asleep whenwe came. But they came swarming out of the ice by the hundreds lastmonth."
"How come Earth doesn't know?"
"The antenna for our long-range transmitter was outside the Dome. One ofthe worms came by and chewed the antenna right off. All we've got leftis this short-range thing we're using and it's no good more than tenthousand miles from here. You're the first one who's been this closesince it happened."
"I get it." Preston closed his eyes for a second, trying to think thingsout.
* * * * *
The Colony was under blockade by hostile alien life, thereby making itimpossible for him to deliver the mail. Okay. If he'd been a regularmember of the Postal Service, he'd have given it up as a bad job andgone back to Earth to report the difficulty.
_But I'm not going back. I'll be the best damned mailman they've got._
"Give me a landing orbit anyway, Ganymede."
"But you can't come down! How will you leave your ship?"
"Don't worry about that," Preston said calmly.
"We have to worry! We don't dare open the Dome, with those creaturesoutside. You _can't_ come down, Postal Ship."
"You want your mail or don't you?"
The colonist paused. "Well--"
"Okay, then," Preston said. "Shut up and give me landing coordinates!"
There was a pause, and then the figures started coming over. Prestonjotted them down on a scratch-pad.
"Okay, I've got them. Now sit tight and wait." He glanced contemptuouslyat the three mail-pouches behind him, grinned, and started setting upthe orbit.
_Mailman, am I? I'll show them!_
* * * * *
He brought the Postal Ship down with all the skill of his years in thePatrol, spiralling in around the big satellite of Jupiter as cautiouslyand as precisely as if he were zeroing in on a pirate lair in theasteroid belt. In its own way, this was as dangerous, perhaps even moreso.
Preston guided the ship into an ever-narrowing orbit, which hestabilized about a hundred miles over the surface of Ganymede. As hisship swung around the moon's poles in its tight orbit, he began tofigure some fuel computations.
His scratch-pad began to fill with notations.
_Fuel storage--_
_Escape velocity--_
_Margin of error--_
_Safety factor--_
Finally he looked up. He had computed exactly how much spare fuel hehad, how much he could afford to waste. It was a small figure--toosmall, perhaps.
He turned to the radio. "Ganymede?"
"Where are you, Postal Ship?"
"I'm in a tight orbit about a hundred miles up," Preston said. "Give methe figures on the circumference of your Dome, Ganymede?"
"Seven miles," the colonist said. "What are you planning to do?"
Preston didn't answer. He broke contact and scribbled some more figures.Seven miles of iceworms, eh? That was too much to handle. He had plannedon dropping flaming fuel on them and burning them out, but he couldn'tdo it that way.
He'd have to try a different tactic.
Down below, he could see the blue-white ammonia ice that was the frozenatmosphere of Ganymede. Shimmering gently amid the whiteness was thetransparent yellow of the Dome beneath whose curved walls lived theGanymede Colony. Even forewarned, Preston shuddered. Surrounding theDome was a living, writhing belt of giant worms.
"Lovely," he said. "Just lovely."
Getting up, he clambered over the mail sacks and headed toward the rearof the ship, hunting for the auxiliary fuel-tanks.
Working rapidly, he lugged one out and strapped it into an empty gunturret, making sure he could get it loose again when he'd need it.
He wiped away sweat and checked the angle at which the fuel-tank wouldface the ground when he came down for a landing. Satisfied, he knocked ahole in the side of the fuel-tank.
"Okay, Ganymede," he radioed. "I'm coming down."
He blasted loose from the tight orbit and rocked the ship down onmanual. The forbidding surface of Ganymede grew closer and closer. Nowhe could see the iceworms plainly.
Hideous, thick creatures, lying coiled in masses around the Dome.Preston checked his spacesuit, making sure it was sealed. Theinstruments told him he was a bare ten miles above Ganymede now. Onemore swing around the poles would do it.
He peered out as the Dome came below and once again snapped on theradio.
* * * * *
"I'm going to come down and burn a path through those worms of yours.Watch me carefully, and jump to it when you see me land. I want thatairlock open, or else."
"But--"
"No buts!"
He was right overhead now. Just one ordinary-type gun would solve thewhole problem, he thought. But Postal Ships didn't get guns. Theyweren't supposed to need them.
He centered the ship as well as he could on the Dome below and threw itinto automatic pilot. Jumping from the control panel, he ran back towardthe gun turret and slammed shut the plexilite screen. Its outer wallopened and the fuel-tank went tumbling outward and down. He returned tohis control-panel seat and looked at the viewscreen. He smiled.
The fuel-tank was lying near the Dome--right in the middle of the nestof iceworms. The fuel was leaking from the puncture.
The iceworms writhed in from all sides.
"Now!" Preston said grimly.
The ship roared down, jets blasting. The fire licked out, heated theground, melted snow--ignited the fuel-tank! A gigantic flame blazed up,reflected harshly off the snows of Ganymede.
And the mindless iceworms came, marching toward the fire, beingconsumed, as still others devoured the bodies of the dead and dying.
Preston looked away and concentrated on the business of finding a placeto land the ship.
* * * * *
The holocaust still raged as he leaped down from the catwalk of theship, clutching one of the heavy mail sacks, and struggled through themelting snows to the airlock.
He grinned. The airlock was open.
Arms grabbed him, pulled him through. Someone opened his helmet.
"Great job, Postman!"
"There are two more mail sacks," Preston said. "Get men out after them."
The man in charge gestured to two young colonists, who donnedspacesuits and dashed through the airlock. Preston watched as they racedto the ship, climbed in, and returned a few moments later with the mailsacks.
"You've got it all," Preston said. "I'm checking out. I'll get word tothe Patrol to get here and clean up that mess for you."
"How can we thank you?" the official-looking man asked.
"No need to," Preston said casually. "I had to get that mail down heresome way, didn't I?"
He turned away, smiling to himself. Maybe the Chief _had_ known what hewas doing when he took an experienced Patrol man and dumped him intoPostal. Delivering the mail to Ganymede had been more hazardous thanfighting off half a dozen space pirates. _I guess I was wrong_, P
restonthought. _This is no snap job for old men._
Preoccupied, he started out through the airlock. The man in chargecaught his arm. "Say, we don't even know your name! Here you are a hero,and--"
"Hero?" Preston shrugged. "All I did was deliver the mail. It's all in aday's work, you know. The mail's got to get through!"
THE END
Transcriber's Note:
This etext was produced from _Amazing Stories_ September 1957. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed. Minor spelling and typographical errors have been corrected without note.
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