I was lifted up and hurled backwards, so violently that if blind luck hadn't saved me I'd have fractured my skull or felt, ripping through my chest, the beaten-drum agony that sets in right after you've shaken hands with a spinal concussion.

I came down heavily, hitting the pavement with a thud. But in falling I went into a kind of half-spin, and landed on my side in a loose-jointed sprawl that just shook me up a little.

I rolled over on my back and stared up in horror. For an instant I was sure that the whole sky had burst into flame. Then the flare dimmed and vanished and I could see that the dust spirals were still there.

I raised myself on one elbow and stared out across the square. The long line of tractors was still there, too. Not one of the vehicles had been blown sky high. And as if that wasn't enough of a miracle the snail-paced one had turned about and was heading straight in my direction.

It wasn't moving at a snail's pace now. It was coming directly at me from mid-way in the square, rumbling and clattering as it came, its heavy treads so ponderously in motion that the pavement under me was beginning to vibrate.

Nearer it came and nearer, swaying a little, and if the driver had been some crazy killer bent on crushing me to death under the treads he couldn't have gone about it more expertly, for he was maneuvering the vehicle just enough to make sure that it would pass directly over me.

How could I doubt it? It had veered slightly and swung back into a straight-line course again, and if I'd tried to drag myself out of its path there was room enough for it to veer again before I could hope to save myself.

It takes several seconds to recover from a scare like that, even when the danger evaporates right before your eyes. All at once the tractor was veering again, but far enough to the left to make me feel certain that I wouldn't be flattened to a pancake if I stayed where I was. But you can feel certain about something like that and go right on remembering what big tractors have done at various times in the past to men unfortunate enough to be caught off guard when there's a killer in the driver's seat.

The vehicle came to a jolting, grinding halt a few yards to the left of me, and the driver swung himself out of the glass-shielded front seat, descended lightly to the ground, and was grabbing me by the arm and helping me to rise before I could get a really good look at him.

He'd descended from the tractor lightly because he was that kind of a man—just about the most fragile-looking guy I'd ever seen. He was lean to the point of emaciation, with gaunt cheeks and sparse white hair that was fluffed out like thistledown by the wind that was blowing across the square.

He had deepset brown eyes, very sharp and piercing and they were glowing now with a kind of feverish brightness, as if his agitation matched my own or had reached a peak that was just a trifle higher. There was nothing surprising about that, if he knew exactly what had happened and it was as bad as I feared it might be.

Despite his frailness, he had the features of a strong-willed man, the chin and mouth firm, the nose pinched a little at the nostrils, as if stubbornness in adversity had become an ingrained habit with him. I had the feeling I'd seen that face before, but I couldn't remember where or under what circumstances.

I was certainly seeing it now under the most nerve-shattering of all circumstances and would not be likely to forget it a second time.

"How are you, all right?" he asked, his eyes searching my face as if he was far from sure I knew myself and the way I looked would tell him more than just a guess on my part. "That explosion was miles from here," he went on breathlessly, "but it lifted the tractor right off the ground, treads and all, for a second. I had the craziest kind of floating sensation until it settled down and kept right on in this direction. I increased the speed, because I sort of felt that a fast-moving machine would have a better chance of not overturning."

I stared at him half-dazedly, feeling like a pawn on a chessboard that had tilted just far enough to make me wonder if it might not still be precariously poised and go crashing at any moment. And since I couldn't see the players I didn't know what the rules of that particular game were or how far they had been abrogated.

"How do you feel?" he asked.

His solicitude amazed me, because if what he'd just said was true—and I had no reason to doubt it—he should have been more shaken up than I was and he seemed to have something on his mind that was making him stare straight past me toward the Big Grayness.

I was staring in the opposite direction. "I'm all right," I assured him. "Just feel ... a little dizzy." I gestured toward the tractors on the far side of the square. "What's over there? Did the explosion come from there?"

He shook his head. "No. I told you it was miles from here, in the direction of the spaceport. That's the Endicott Administration Building, fuel conveyor sections and two-thirds of the distributing units. The tractors are all owned by Endicott. I backed this one out from between them and had just about gotten it turned around when the blast hit me."

"I know," I said. "I saw you. I wondered why only one tractor—"

That was as far as I got, because what hit me then was more jolting than any blast could have been, and it wasn't even physical. Just one word he'd let drop with a delayed-action fuse attached to it made me snap my head back and look at him in desperation. He had no way of knowing what was in my mind, but you don't think of that when you want someone to do you a favor that's of life-and-death importance to you.

I wanted him to withdraw that one word, to pretend at least that he hadn't said it. It didn't have to be true, he could have been just guessing.

The word was "spaceport." It couldn't matter that much to him, surely. It wasn't his wife but mine who was at the spaceport, and if he was wrong about where the explosion had taken place it would cost him nothing to be merciful and admit that he was far from sure about it.

But before I could hope to get such an admission out of him he sounded a knell to the granting of favors by saying: "Wendel technicians are activating Endicott fuel cylinders in different sections of the Colony. They're trying to turn the Colonists against Endicott by committing mass murder. The cylinders will only destroy an area of a few square miles, because they're not in the multiple-megaton, nuclear warhead category. We never thought they'd be turned into bombs."

Then came the knell. "We were warned about this, by a Colonist who's on his way to the spaceport with one of the cylinders. Or he may be there already. He just spoke to us briefly on the tele-communicator. That explosion came from the direction of the spaceport, but it may not be the one we were warned about. They may be trying to dismantle another cylinder at the spaceport right now. They won't succeed, because only an Endicott technician would know how to go about it."

"Do you know?"

He nodded. "Yes ... I can dismantle it. I can get to the spaceport in about fifteen minutes, if I drive between the aerators and turn right just before I get to the hospital. The clear-away from that point on will take me through a section of the Colony and then straight out across the desert to the spaceport. The Colonist who talked with us made a serious mistake, but it wasn't his fault. He had no way of knowing that it takes a fuel cylinder at least forty-five minutes to build up to critical mass after it's been activated. In some cases—fifty or fifty-five minutes."

He paused an instant, then went on quickly. "He should have brought it here. We could have dismantled it in time. But he was afraid it would kill several thousand people if it went off anywhere near his home, or in this section of the Colony. He also over-estimated the area that would be demolished by the blast. When he talked to us he was two-thirds of the way to the spaceport and if we'd told him to turn back then and bring the cylinder here the risks would have been too great. We had to let him go on. I said they can't dismantle it at the spaceport. But there's a slim chance they can ... because there may be an Endicott man there or someone who knows enough about Endicott cylinders to make a hit-or-miss try. With luck, he may just possibly succeed. But I doubt it."

"You doubt it? Good God—"

"I doubt it very much. That's why it's so important for me to get there as fast as I can. It's my responsibility—and I refuse to share it with anyone. There are times when a man must face death alone."

"Who are you?" I asked.

"A man with much to answer for, the opposite of a good man. I'm Kenneth H. Hillard, President of the Endicott Combine."

It stunned me for a moment, because it was as big a bombshell as Nurse Cherubin had exploded back at the hospital when she'd nodded toward a slumped caricature of a man and told me exactly who I'd been banging around.

But it didn't stun me for long, because even the showdown miracle of two Mr. Big's taking matters into their own hands when all of the chips were down—Hillard was also a giant despite his frailness and a better man than Wendel could ever hope to be—even the wonder and strangeness of it was of less concern to me at that moment than the danger that Joan was in.

I told him then. "I'm going with you," I said. "I've every right. If I'm cutting in on your yen to face death alone ... that's just too bad. I'm going with you, or you don't go at all. I pack quite a wallop, and you may as well know it. Wendel does."

"Your wife. I see...."

"I hope to Christ you do—"

"Get in!" he said sharply. "I may need you. I'm not a well man. My heart—"

We climbed in and he tugged at the brakes, releasing them and the big vehicle lumbered into motion.

It was already pointed in the right direction, and in less than half a minute—the second time within fifteen minutes for me—we were deep in the Big Grayness, with the walls of the aerators looming up on both sides of us.

Up above all of the sunlight had dwindled to the vanishing point and the gigantic artificial cavern was lighted now along its entire length by cold light lamps embedded in the walls at fifty-foot intervals. The solid, three-dimensional world outside our minds, whatever segment of reality we happen to be passing through, never looks quite the same to any two individuals. It is always, in a sense, a special creation, colored and altered by the human imagination.

To me the cold light lamps were chillingly like enormous eyes, keeping us under constant scrutiny. The scrutiny of giants, standing motionless in shadows, with just their luminous eye-sockets visible. It was as if any moment, promoted by some wild whim, the giant forms might take a violent dislike to us, might raise mace-like metal fists and smash the tractor, very much as a robot giant had smashed a Wendel agent in space, with a fiendishly mechanical rancor.

But to the frail man at my side the aerator walls may have been chilling in a quite different way, if he was giving the Big Grayness any thought at all.

Apparently he wasn't, because when his voice rose above the rumble of the treads he didn't once mention the aerators or the pale blue light that was glimmering on the hood of the tractor.

"It's the beginning of the end—either one way or the other," he shouted. "Either Wendel will be destroyed by the Colonists themselves for committing mass murder, or we'll go down under a juggernaut that can't be stopped. Sometimes you can't smash absolute evil, when it's backed up by absolute power."

I raised my voice as high as he'd done, because I wanted to be sure he'd hear me. "It will always be stopped in the end, I think—if you have enough moral courage. That's a dynamic in itself, the most formidable of all weapons. All history confirms it."

"I wish I could believe that!" he shouted back. "But I'm not so sure. And you have to fight with reasonably clean hands. Endicott is almost as guilty as Wendel, except that it would rather be destroyed than resort to mass murder."

"That's two-thirds of the right," I shouted back. "That's where the biggest dividing line comes. Every tyranny in human history that has resorted to mass murder has gone down into everlasting night and darkness and very quickly. The few that survived to die a natural death drew back at that point. The great, utterly ruthless destroyers always perish."

We both fell silent then, because there are times when the whole of the future and everything that human anger and courage can do to safeguard the future and keep it from destruction seems less important than coming to grips with an immediate, life-and-death emergency. When you do that you're going all out to safeguard the future as well, but you don't think of it in that way. Just getting to the spaceport in time—Oh, God, yes, in time to be at least a little ahead of time, so that Hillard would have steady nerves and could dismantle the cylinder with cautious precision, with no zero-count demoralization to make his fingers stray from the right wires—just getting there and finishing the job before the spaceport could become a translucent cone of fire was a million times as important to me, right at that moment, as the Wendel-Endicott war.

A million times as important, Ralphie boy. Don't be ashamed of feeling that way. If the spaceport blows up, and there's no Joan any more, and the universe comes to an end for you, you've no sure guarantee that the actors who will step into your shoes and occupy the center of the stage will make any better job of it than you've been doing. So it will be a loss, however you slice it, because the death of two lovers is always a loss. You fight better when you've been given that best of all head starts.

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