There was no waiting ambulance in the driveway. I descended the stairway, twelve metal steps railed in on both sides, feeling grateful for what she'd said right after I kissed her. "Don't worry about your wife. If Wendel tries to make us send for her we'll find a way to roast him over a slow fire until you're together again. There are three doctors who will put up a stiff fight and I'm going to set to work on all of them. You've no idea what a hospital can do with just the right kind of delaying tactics."

It took me less than two minutes to half-encircle the driveway, take the turn she'd recommended and strike out for the Colony between the towering gray walls of the aerators.

The Big Grayness. I'd seen photographs of that tremendous engineering project in my hell-bent-for-adventure years, when I'd sat at a desk in a schoolroom, and imagined what it would be like to take part in the construction work, standing on a dizzy height with an electronic riveter in my hand, watching blue lights go on and off and sparks fly up into the cool Martian night beneath a wilderness of stars.

The reality was very much as I'd imagined it as a school kid, except that I wasn't a construction worker looking down over it, a human fly with a man-size job to do, but a guy that kid wouldn't have recognized, his footsteps echoing on the catwalk at the base of it. I had a giant-size job to do, but how could he have known it would some day turn into anything that big?

It wasn't even a project anymore—half of it still in the blueprint stage. It was completed and the towering gray walls were firm and solid, and the grills were sending oxygen spiraling out over the Colony without making me feel light-headed at all.

Right at that moment I'd have welcomed a little oxygen intoxication but the aerator-system didn't work that way. The flow was regulated directly at the source, kept under controlled pressure and diffused outward high up by rotary circulators. As it spread out over the Colony it was drawn down to breathing level by another system of circulators, stationed at intervals about the Colony and extending twenty-five miles out into the surrounding desert.

If you wanted to experience oxygen intoxication you had to strap a tank to your back and breathe the stuff in through a tube in the old way. But no one in his right mind would do that deliberately, for an excess of oxygen can be five-ways dangerous on a planet where what you have to worry about most is over-stimulation.

There were catwalks on both sides of the aerator walls, with a central lane wide enough for vehicles to pass in opposite directions. I kept to the right hand side all the way to the Colony, and it took me about thirty minutes to get there. My strength amazed me. It probably wasn't quite up to par. But I only had to stop twice to rest and then only for a minute or two.

Two ambulances passed me, their red tail-lights blinking, but the drivers didn't even turn their heads as the vehicles went droning through the Big Grayness. Up above the sunlight was waning, and turning red, but only a diffuse glow filled that two hundred-foot-high artificial cavern.

Three aerator-system workers, walking shoulder to shoulder, gave me a bad jolt for a moment, for they had the look of Wendel police agents. I encountered them just beyond a break in the cavern wall, where a cluster of pre-fabs with children playing in the yards made five or six acres of stony ground resemble a manufacturing town suburb Earthside.

I should have known better than to be alarmed, because the three men approaching me looked eager and expectant, as if they knew that a few steps more would bring relaxation after toil and the warmth and glow of a family reunion.

But they had the husky build and sharp-angled features of Wendel police officers and I stayed alert until one of them came to a dead halt and looked me over genially. "New on the job, aren't you, Buster? Don't remember having run into you before. They keep putting on so many new men it's hard to be sure."

"That's right," I said. "I live about two miles further on."

"Well, it isn't the best job in the world, Buster, as I guess you've found out already. You get sucked into a grill sometimes, and breathe nothing but oxygen until you feel like a blue baby they're trying their best to save, even if they have to fanny-whack him to get the stuff out of his lungs for a week or two afterwards."

"Don't discourage him, Pete," the tallest of the three chided. "You have a cold, cold heart. It doesn't happen often."

"You bet it doesn't ... or my wife would have been a widow long before this. Well ... good luck, Buster. Be seeing you around ... I hope."

I felt so relieved I didn't even resent the "Buster." He was just a big grinning ape who liked to kid the living daylights out of his fellow workers, whenever he thought he could get away with it. No harm in him, and though there might have been times when I'd have been tempted to take a poke at him ... I had no such impulse now. I just wanted to be able to look back and see him dwindling in the distance.

I ran into only one other person before the Big Grayness terminated. She was a stout, matronly-looking woman carrying a baby and she nodded and smiled warmly when she saw me staring at the infant, as if she wouldn't have at all minded if I had been its father.

For an instant there flashed into my mind the nerve-relaxing picture that every normal male has of himself at times—the humble-station husband, big-bosomed wife picture. You're Mr. Run-of-the-Mill, just a simple guy, working hard at a lathe or feeding processed food tins into a vacuumator. You come home at night with no worries, kick off your shoes and she's there to make the creature comforts seem important. A good meal on the table, fit for a king with a hearty appetite—do kings ever have that kind of appetite?—children romping all over the house—a round half-dozen upstairs and down—and the kind of night's sleep you don't get when you have responsibilities weighing on you. The top-echelon kind that can drive you half out of your mind. It's there for the taking if you really want it, if you don't wear a silver bird on your uniform when they add up the score and ask you why in hell you haven't done better?

It's not quite an accurate picture, because that kind of guy has worries too—plenty of them. He has to buy shoes for the children and grin and be tolerant when his wife turns shrewish, as every woman with a large family and a big grocery bill is bound to do at times. But still, when you balance the good against the bad, who gets the most out of life—Mr. Run-of-the-Mill or Mr. Big?

Well ... however much I might fume about it ... I had to be what I was. I could honestly say that I'd never had any driving ambition to be the kind of Mr. Big Wendel was. I just had a kind of inner compulsion to be true to the best that was in me, to preserve my integrity and use whatever wild talents I had to enrich human life and have some fun while doing it. If I couldn't always have fun, if illness or death or just plain bad luck prevented me from living life to the full and enjoying it ... I'd known that when I'd cut the cards, hadn't I? You have to play whatever cards destiny hands you.

Just before I reached the last quarter mile of the aerator marathon I passed another dwelling section, with more kids scampering about and three or four women standing in the doorways of the pre-fabs. They didn't look big-bosomy, but slender as willow trees and very beautiful.

I certainly wasn't running, but it was a marathon in my book, the walking kind where you keep your body held rigid, your arms bent sharply at the elbows. There was only one good thing about it. I didn't have to worry about out-distancing the other walkers, because it was a one-man marathon.

I came out into the biggest square I'd ever seen. The one opposite the skyport I'd crossed with just as much tension and uncertainty mounting in me an eternity ago on Earth was just about one-fourth as large, give or take a few square yards of shadowy pavement.

In a way, the Big Grayness was still with me, because there were gigantic, interlocking shadows everywhere and although there was nothing but open sky overhead spirals of wind-blown sand were swirling across it, half-blotting out the waning sunlight.

When you're sure that Death hasn't played his final trump or even relaxed his vigilance and you could be yanked right back to confront him at any moment a square as big and empty and desolate-looking as that doesn't give you any support at all.

All right, there was life and movement in it, if you want to call a long line of tractors standing end to end on the far side, one of them snail-active, life and movement.

One of the trucks seemed to be backing up a little and edging out from between the others, but I couldn't even be sure of that before an ear-splitting blast of sound and a blinding flash of light shattered my last link with the sane universe.

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