by Hal Clement
an engineer," he finished rather lamely. "Now do you want this job?"
Tumble's eyes went back to the picture. His freckles showed a little more clearly than usual.
"I guess I don't," he admitted. "Say, Pete, wasn't I supposed to get some more measurements for my space suit today? Maybe we'd better get over there; I wouldn't want 'em to feel rushed about anything."
"All right." Peter put the book back on its shelf and followed the younger boy from the room. He was rather pleased with himself; he'd made Tumble do some thinking. Then he began to wonder whether he might not have been overdoing it; after all, he didn't want to frighten the kid so badly that he'd back out of the trip.
"Pete, are you sure those suits can stand the vacuum?" Tumble asked as they fell into step. "I should think they'd just burst, like balloons that have been blown too far."
"No, there's no worry about that. The plastics they're made of are about four times as strong as the same thickness of steel, the engineers told me. The joints are so well made that it would take years for all the air to leak out. There are batteries to run the radios and the gadgets that renew the air you breathe, but as long as you're in sunlight the air renewers use that for power; even if you're in the dark for days and the batteries run down, there are spare oxygen tanks. They have temperature controls to keep you from freezing—well, like every other machine you see around here, they have anywhere from fifty to two or three hundred years of ideas worked into them. I couldn't begin to describe how they're made, let alone make one myself, and I'd be willing to bet no one else could either!"
"But how can anyone make them, then?" Tumble sounded doubtful, but at least seemed to have stopped worrying.
"One person doesn't, any more than one person makes a car or an airplane—or the Polaris." That set the redhead off an another slant.
"Say," he said, "I thought that ship was a rocket."
"She is."
"Then where does the gas squirt out? Every rocket I've ever seen pictures of had a big hole in the stern. The Polaris just has a big flat block of metal."
"The holes are there, only they're too small to see— about five thousand of them to every square inch, each one running straight through the block for about eight feet. The water that goes into the holes at the top is picked up and pushed out by forces something like magnetism, so it squirts away at thousands of times the speed any other rocket ever managed. That's why the Polaris and the other ships with this motor don't need to be nearly all fuel, the way the earlier ones were."
"I don't get it."
And, although Peter was a fairly good teacher, Tumble was a long, long time understanding all that made a Phoenix rocket work. He certainly didn't on the night when all the boys were ordered to get to bed early, since they would have to be up before three the following day to get ready for the flight.
No one is really awake at that hour of the morning, and not even the excitement the boys naturally felt as they got into their space suits, checked them as they had been taught, and accompanied the others out to the ship was enough to make them really alert until they got aboard.
Bowen and the pilot went all the way up to the nose, over two hundred feet from the ground. The boys and the two other men who were going on duty at the station began strapping themselves in the harness provided in the next room down, although there was no particular reason to expect any heavy jolts.
The man in charge of the passenger compartment plugged a line from his space suit into a phone connection on the wall, and reported that everyone there was ready to go. The pilot's voice came back.
"All right. We still have eight minutes before we lift. Does everyone down there have his phone plugged in?" The boys had not, and the man quickly showed them what to do—no one had told them about the phone connections in the Polaris, though they had been talking to each other over the radios in the suits.
In the control room, the pilot carefully checked the punched tape which was feeding instructions to the automatic control. Several times he checked it against the time signals coming from Washington; each time it proved correct.
"Stand by to lift!" he called suddenly, as a solid row of punches extending entirely across the tape disappeared into the mouth of the autopilot. Everyone tensed; they trusted the engineers, but mistakes were sometimes made....
Those in the blockhouse outside saw the air under the Polaris suddenly glow a dazzling white. The radiance spread to the concrete, which started to crumble and spall away; in the few seconds it took to raise the ship a hundred yards, a foot-deep hole was eroded in the surface. Then the ground began to cool, and the watchers shifted their eyes to follow the great metal bullet.
It was rising with apparent slowness, the air under it glowing as though a giant searchlight were shining from its base. A wash of superheated gas struck the blockhouse. The whole area was humming in tune with the roar of the ultrafast gas column jetting from the Polaris' drive unit. Very gradually the sound died away, and the glow faded to a spark; finally that, too, vanished in the early morning sky.
11
THE LONG FALL
THE boys had read their share of books dealing with space travel, and had seen more than one motion picture dealing with the same subject. These had all been written before the Phoenix motor was developed, and in spite of their knowledge everyone but Peter rather expected to feel himself dragging down on his harness and the blood rushing from his head under the ship's acceleration.
This did not happen; the tremendous accelerations mentioned in the stories were needed with chemical-powered rockets which had to get their speed before the fuel gave out, but the Polaris lifted herself almost gently into the sky. At no time during the first part of the flight did the weight of the people and objects aboard get more than ten percent above normal, and after the first three minutes of lift the pilot permitted his passengers to get out of their harnesses and move around freely.
The boys naturally headed for the few windows the ship possessed.
There was much to see. The sun had not risen at Niagara when the Polaris lifted, but it was visible now, glaring in a midnight-black sky. Below it a narrow crescent, blurred and hazy, marked all that could be seen of the earth. No details showed through the blanket of atmosphere except a single spot of brilliant light. This was the reflection of the sun in the surface of Lake Erie, and as they watched, it faded and disappeared. The Polaris was climbing at an ever-increasing rate, her automatic controls tilting her course toward the east and south, so that the lake no longer lay between her and the sun. At the same time the crescent grew broader, and as the rocket tilted they could look straight down and see vague details through the atmosphere.
It was Tumble who first noticed that the earth was no longer below them—that "down" was still toward the floor on which they were standing, while the world seemed to have swung a trifle to the side. It was just possible to see the outline of Erie and judge where Niagara must be even though it was not yet in sunlight, and it was no longer straight behind them. Peter was still trying to explain this to Tumble when a call from Dart interrupted them.
The Ranger boys had moved to the opposite window, and the younger one's loud reaction to what they saw brought the others hurrying over with the problem of net acceleration still unsettled. They did not blame Dart for his excitement; for although they had all seen a night sky, they had never imagined one such as they glimpsed through this port.
The sun, on the far side of the rocket, might as well not have existed. The Polaris was far above any measurable traces of Earth's air, and the scattered sunlight which hides the stars from sight in the daytime was absent. The stars did not wink at the boys; they stared, forming a peppering of steady points of light on the infinitely deep background of blackness; among them, very high above the hazy arc of darkness, which was the night side of the earth, hung the moon. It was now well past full; the raggedness of the western side could be seen even without a telescope, and the great dark plains which have made the
"man in the moon" to generations of Earthbound children were clear as the eyes in a skull. Tumble stared in rapt silence, and the others were almost as awe-struck.
"Why is it off to the side?" asked the redhead finally. "Shouldn't we be heading straight to it?"
"No, for two reasons," replied Peter. "One is that we aren't going there—yet. The other is that even if we were, we could never follow a straight-line course in space; it's moving, and we'd have to head for the place it would be when we were to get there."
"I'll believe the second of those remarks," was the answer. There was nothing more said; everyone continued to look at the sky.
The stars were unbelievable, and the planets they had seen in the telescope were there too, though at first Venus was too nearly straight ahead to be seen. As the rocket tilted farther, however, the cloudy planet swam into view through the port they were using. Its appearance brought an awe-struck whistle from one of the men, and Tumble and Dart were both sure that they could see its crescent form with the naked eye. Peter and Bart doubted whether this could be, but even they found they could see three of Jupiter's moons. Peter was annoyed with himself for failing to find out before takeoff which of the satellites would be visible, and tried to figure out which the missing one must be from the motions he and the others had observed through the telescope on the previous few nights.
He was still at it when they were interrupted by Bowen's voice from the control room.
"Start getting back in your harnesses, boys. I'm coming down to your deck."
"What's up?" asked Bart.
"We'll be turning over in six minutes, and you'd better be tied down by then. We'll have to stop accelerating." He said no more, but three of the boys knew what he had left unsaid. So did the men, for they were losing no time at the job of strapping themselves once more at their take-off stations. Tumble alone was at a loss, and as was coming to be his custom, he asked Peter to explain what was going on.
"We've been picking up speed all along," was the reply, "and are now going very much faster than the station; we have to swing the ship so that the tubes point the other way, and use them for slowing down."
"I see. You pick up speed for half the journey, and get rid of it for the other half."
"It's not quite that simple; we didn't pick up speed as fast as we'll lose it, because the earth's gravity was fighting us. Besides, we don't lose all our speed, because the satellite is doing something like four miles a second, and we have to get in touch with it." Tumble thought for a moment.
"Then, I should think we'd go more than halfway before this turning over business was needed?"
"That's right, this time. Going back to the earth it would be different."
"I see." Tumble said no more, but did a great deal of thinking. Big as the moon looked with no air to cut off its light, even he could see that they had not come anything like halfway to it. Maybe these people had been telling the truth—but that was silly, he told himself. Lerch would never have lied to him.
"Why do we need to strap in?" he asked at this point in his thoughts.
"Because while we're turning over, the main drive will be off; and until it goes on again, we'll be weightless," Peter stated. He did not know how much Tumble knew of the effects of free fall—certainly plenty had been written in the papers since the troubles of the first flight had been made public, but Tumble didn't seem to believe all he read in the papers.
As the moment when Peter's idea would receive its first trial drew near, his heart was thudding a good deal faster than usual, and he could feel a damp trickle of perspiration on his forehead. He could not see the faces of his friends very clearly through their helmets, but Dart was quieter than usual as he attended to his harness, and his brother made a half-checked motion toward his head as though he had forgotten for a moment that he could not wipe his brow while the helmet was in place.
The news did not seem to bother Tumble. Even the arrival of Bowen from the deck above, and his care in placing himself where he could watch the clock set into one wall, did not bring forth any remark from the little spy, but the others could read a great deal into his silence.
"How long?" asked Bart.
"Thirty-five seconds, on automatic," replied Bowen. "The side jets could whip her around in five, on manual handling, but it would take a good deal longer for a pilot to head her exactly right; besides——"
"I see." Bart said no more, and they all waited as the second hand swept again and again around the dial before them. None of the boys had noted the time when Bowen had first called down, so they were not sure just when the power was to go; but they learned. Bowen himself told them, in a voice that suggested that the words were being dragged from his lips against his will.
"Thirty more seconds—fifteen—ten—five—"
And someone cut the rope.
That was the way Tumble described it later. He had not known what to expect, in spite of the newspapers. He was, of course, used to the sensation of falling; the number of hours he had spent on flying rings, trapeze, and trampoline took care of that. The feeling, however, had never lasted so long, and after perhaps five seconds he gasped, "How long before we hit the ground?"
"We don't." It was Peter who answered, and he was sure ever afterward that Tumble's question had been the difference between success and failure of his whole idea.
For he had known what to expect. He, too, had known the sensation of falling, experienced time and time again between diving board and water. He had been telling himself that of course the ship would be falling, but that with her velocity she could never strike the earth at all, nor any other thing in space until long after everyone aboard had died of old age. In spite of his knowledge and what he had tried to tell himself, something had gone wrong. He knew the ship was traveling upward, in spite of his sensations—but which way was up? There was a ceiling—that should be above, though it didn't feel that way. For a moment he almost steadied; and then he saw the earth through one of the ports. His mind knew that earthward wasn't really down any more, but his sensations didn't agree. His eyes were telling him two different stories; his sense of balance was telling him nothing—or was it everything? His muscles were starting to tremble in a way that an airplane pilot who had suffered from vertigo would have recognized, and he had almost lost control of himself—when Tumble asked his question.
"We don't." Those words left Peter's lips almost without his thinking—they were the ones he had been saying to himself in answer to the very same question that the redhead had asked. The very act of speaking jerked his attention back from the crazy-quilt of sensations that were coming from eyes, muscles, and balance organs, and he was suddenly himself again. "We're heading up, still." These words were carefully chosen; he could think, once more. "We're going so fast that the earth's gravity could never pull us back, and it would be years before we could hit anything else. It's just a long, long dive, Tumble; take it easy. We'll have weight again in ten seconds." His eyes had focused on the clock, and he very carefully avoided looking at anything else. At least, the clock dial had a top to it.
Tumble did not answer, and the heavy breathing that came over the radios certainly did not belong to him alone. Others were afraid, too, and Peter did not blame them. His own stomach felt—
All right. Weight came back, along the hum of the drive, so suddenly that the knees of everyone in the room gave under the load. Tumble sagged just a little. Everyone else dropped as far as the safety harness would allow. The boys came back to their feet at once and began unfastening their straps without waiting for orders or permission; the men did not. Bart was the first to notice this.
"Uncle Jim! Are you all right?" Wrenching furiously, he got the rest of his harness off and leaped across the floor to his uncle. A shaky voice reassured them.
"Not exactly all right, but I will be. It—it doesn't get any Better with practice, as I said. See about the others, will you? I don't want to stand up for a few moments; my sense of balance has gone again, I
'm afraid."
The boys obeyed him, in grim silence. The other men were in about the same condition as Bowen; but all were able to stand up again after a few minutes' rest, and Dart, who had gone up to the control compartment, reported that the pilot was also recovering.
Bart had muscle cramps in arms and legs; he had held on to his self-control by sheer determination, with every muscle so tense that it hurt. His brother had felt about the same as Tumble, but had got through the worst by concentrating on Peter's words as he tried to explain what was going on. All four of the boys had come through far better than the men, and three of them were aching to get together where they could discuss the matter in private. Tumble felt no need for privacy; he told of his sensation at great length, without caring much whether anyone listened.
"You know, it's just as well I didn't eat much breakfast this morning," he remarked. "That long fall is rough on the stomach. Takes a bit of getting used to, I guess. Pete, did you ever try a dive as high as that one?"
Bowen snapped off his radio for the time being. His stomach was in no condition to hear the whole thing talked over again. He had never been seasick or airsick, but free fall was quite another matter. He began, with some pain, to plan just how he would tell the boys about the job that awaited them in another twenty minutes.
12
TUMBLE TEACHES
"IT'S over for now, anyway," remarked Peter. "I guess it's kind of lucky the ship was on automatic control just then."
"Can that tape take it right up to the satellite?" asked Tumble. The question came so naturally that no one thought to be surprised for several seconds; then they realized that this was the first time he had been willing to admit that the Polaris might be going anywhere but to the moon.
"No, it can't," Bowen replied, without making any comment on the redhead's apparent change of heart. "It will bring us close, and match our speed to theirs; then we turn over the controls to them, and they bring us in by radio."
