Postmark Ganymede, Robert Silverberg [book club reads .TXT] 📗

Preston paused. Then: "Postal Ship 1872, Lieutenant Preston aboard. I acknowledge message."

There was a stunned silence. "Preston? Hal Preston?"

"The one and only," Preston said.

"What are you doing on a Postal ship?" Mellors asked.

"Why don't you ask the Chief that? He's the one who yanked me out of the Patrol and put me here."

"Can you beat that?" Gunderson asked incredulously. "Hal Preston, on a Postal ship."

"Yeah. Incredible, isn't it?" Preston asked bitterly. "You can't believe your ears. Well, you better believe it, because here I am."

"Must be some clerical error," Gunderson said.

"Let's change the subject," Preston snapped.

They were silent for a few moments, as the three ships—two armed, one loaded with mail for Ganymede—streaked outward away from Earth. Manipulating his controls with the ease of long experience, Preston guided the ship smoothly toward the gleaming bulk of far-off Jupiter. Even at this distance, he could see five or six bright pips surrounding the huge planet. There was Callisto, and—ah—there was Ganymede.

He made computations, checked his controls, figured orbits. Anything to keep from having to talk to his two ex-Patrolmates or from having to think about the humiliating job he was on. Anything to—

"Pirates! Moving up at two o'clock!"

Preston came awake. He picked off the location of the pirate ships—there were two of them, coming up out of the asteroid belt. Small, deadly, compact, they orbited toward him.

He pounded the instrument panel in impotent rage, looking for the guns that weren't there.

"Don't worry, Pres," came Mellors' voice. "We'll take care of them for you."

"Thanks," Preston said bitterly. He watched as the pirate ships approached, longing to trade places with the men in the Patrol ships above and below him.

Suddenly a bright spear of flame lashed out across space and the hull of Gunderson's ship glowed cherry red. "I'm okay," Gunderson reported immediately. "Screens took the charge."

Preston gripped his controls and threw the ship into a plunging dive that dropped it back behind the protection of both Patrol ships. He saw Gunderson and Mellors converge on one of the pirates. Two blue beams licked out, and the pirate ship exploded.

But then the second pirate swooped down in an unexpected dive. "Look out!" Preston yelled helplessly—but it was too late. Beams ripped into the hull of Mellors' ship, and a dark fissure line opened down the side of the ship. Preston smashed his hand against the control panel. Better to die in an honest dogfight than to live this way!

It was one against one, now—Gunderson against the pirate. Preston dropped back again to take advantage of the Patrol ship's protection.

"I'm going to try a diversionary tactic," Gunderson said on untappable tight-beam. "Get ready to cut under and streak for Ganymede with all you got."

"Check."

Preston watched as the tactic got under way. Gunderson's ship traveled in a long, looping spiral that drew the pirate into the upper quadrant of space. His path free, Preston guided his ship under the other two and toward unobstructed freedom. As he looked back, he saw Gunderson steaming for the pirate on a sure collision orbit.

He turned away. The score was two Patrolmen dead, two ships wrecked—but the mails would get through.

Shaking his head, Preston leaned forward over his control board and headed on toward Ganymede.

The blue-white, frozen moon hung beneath him. Preston snapped on the radio.

"Ganymede Colony? Come in, please. This is your Postal Ship." The words tasted sour in his mouth.

There was silence for a second. "Come in, Ganymede," Preston repeated impatiently—and then the sound of a distress signal cut across his audio pickup.

It was coming on wide beam from the satellite below—and they had cut out all receiving facilities in an attempt to step up their transmitter. Preston reached for the wide-beam stud, pressed it.

"Okay, I pick up your signal, Ganymede. Come in, now!"

"This is Ganymede," a tense voice said. "We've got trouble down here. Who are you?"

"Mail ship," Preston said. "From Earth. 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 land here. It's rough on us, missing a mail trip, but—"

Preston said impatiently, "Why can't I land? What the devil's going on down there?"

"We've been invaded," the tired voice said. "The colony's been completely surrounded by iceworms."

"Iceworms?"

"The local native life," the colonist explained. "They're about thirty feet long, a foot wide, and mostly mouth. There's a ring of them about a hundred yards wide surrounding the Dome. They can't get in and we can't get out—and we can't figure out any possible approach for you."

"Pretty," Preston said. "But why didn't the things bother you while you were building your Dome?"

"Apparently they have a very long hibernation-cycle. We've only been here two years, you know. The iceworms must all have been asleep when we came. But they came swarming out of the ice by the hundreds last month."

"How come Earth doesn't know?"

"The antenna for our long-range transmitter was outside the Dome. One of the worms came by and chewed the antenna right off. All we've got left is this short-range thing we're using and it's no good more than ten thousand miles from here. You're the first one who's been this close since it happened."

"I get it." Preston closed his eyes for a second, trying to think things out.

The Colony was under blockade by hostile alien life, thereby making it impossible for him to deliver the mail. Okay. If he'd been a regular member of the Postal Service, he'd have given it up as a bad job and gone 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 creatures outside. 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. Preston jotted them down on a scratch-pad.

"Okay, I've got them. Now sit tight and wait." He glanced contemptuously at the three mail-pouches behind him, grinned, and started setting up the orbit.

Mailman, am I? I'll show them!

He brought the Postal Ship down with all the skill of his years in the Patrol, spiralling in around the big satellite of Jupiter as cautiously and as precisely as if he were zeroing in on a pirate lair in the asteroid belt. In its own way, this was as dangerous, perhaps even more so.

Preston guided the ship into an ever-narrowing orbit, which he stabilized about a hundred miles over the surface of Ganymede. As his ship swung around the moon's poles in its tight orbit, he began to figure 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 he had, how much he could afford to waste. It was a small figure—too small, 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 me the 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 planned on dropping flaming fuel on them and burning them out, but he couldn't do it that way.

He'd have to try a different tactic.

Down below, he could see the blue-white ammonia ice that was the frozen atmosphere of Ganymede. Shimmering gently amid the whiteness was the transparent yellow of the Dome beneath whose curved walls lived the Ganymede Colony. Even forewarned, Preston shuddered. Surrounding the Dome 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 rear of the ship, hunting for the auxiliary fuel-tanks.

Working rapidly, he lugged one out and strapped it into an empty gun turret, 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 would face the ground when he came down for a landing. Satisfied, he knocked a hole 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 on manual. The forbidding surface of Ganymede grew closer and closer. Now he could see the iceworms plainly.

Hideous, thick creatures, lying coiled in masses around the Dome. Preston checked his spacesuit, making sure it was sealed. The instruments told him he was a bare ten miles above Ganymede now. One more swing around the poles would do it.

He peered out as the Dome came below and once again snapped on the radio.

"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 that airlock open, or else."

"But—"

"No buts!"

He was right overhead now. Just one ordinary-type gun would solve the whole problem, he thought. But Postal Ships didn't get guns. They weren't supposed to need them.

He centered the ship as well as he could on the Dome below and threw it into automatic pilot. Jumping from the control panel, he ran back toward the gun turret and slammed shut the plexilite screen. Its outer wall opened and the fuel-tank went tumbling outward and down. He returned to his control-panel seat and looked at the viewscreen. He smiled.

The fuel-tank was lying near the Dome—right in the middle of the nest of 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 the ground, 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, being consumed, as still others devoured the bodies of the dead and dying.

Preston looked away and concentrated on the business of finding a place to land the ship.

The holocaust still raged as he leaped down from the catwalk of the ship, clutching one of the heavy mail sacks, and struggled through the melting 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 donned spacesuits and dashed through the airlock. Preston watched as they raced to the ship, climbed in, and returned a few moments later with the mail sacks.

"You've got it all," Preston said. "I'm checking out. I'll get word to the Patrol to get here and clean up