No, you’re wrong. I’m not your father’s ghost, even if I do look a bit like him. But it’s a longish story, and you might as well let me in. You will, you know, so why quibble about it? At least, you always have ... or do ... or will. I don’t know, verbs get all mixed up. We don’t have the right attitude toward tenses for a situation like this.

Anyhow, you’ll let me in. I did, so you will.

Thanks. You think you’re crazy, of course, but you’ll find out you aren’t. It’s just that things are a bit confused. And don’t look at the machine out there too long--until you get used to it, you’ll find it’s hard on the eyes, trying to follow where the vanes go. You’ll get used to it, of course, but it will take about thirty years.

You’re wondering whether to give me a drink, as I remember it. Why not? And naturally, since we have the same tastes, you can make the same for me as you’re having. Of course we have the same tastes--we’re the same person. I’m you thirty years from now, or you’re me. I remember just how you feel; I felt the same way when he--that is, of course, I or we--came back to tell me about it, thirty years ago.

Here, have one of these. You’ll get to like them in a couple more years. And you can look at the revenue stamp date, if you still doubt my story. You’ll believe it eventually, though, so it doesn’t matter.

Right now, you’re shocked. It’s a real wrench when a man meets himself for the first time. Some kind of telepathy seems to work between two of the same people. You sense things. So I’ll simply go ahead talking for half an hour or so, until you get over it. After that you’ll come along with me. You know, I could try to change things around by telling what happened to me; but he--I--told me what I was going to do, so I might as well do the same. I probably couldn’t help telling you the same thing in the same words, even if I tried--and I don’t intend to try. I’ve gotten past that stage in worrying about all this.

So let’s begin when you get up in half an hour and come out with me. You’ll take a closer look at the machine, then. Yes, it’ll be pretty obvious it must be a time machine. You’ll sense that, too. You’ve seen it, just a small little cage with two seats, a luggage compartment, and a few buttons on a dash. You’ll be puzzling over what I’ll tell you, and you’ll be getting used to the idea that you are the man who makes atomic power practical. Jerome Boell, just a plain engineer, the man who put atomic power in every home. You won’t exactly believe it, but you’ll want to go along.

I’ll be tired of talking by then, and in a hurry to get going. So I cut off your questions, and get you inside. I snap on a green button, and everything seems to cut off around us. You can see a sort of foggy nothing surrounding the cockpit; it is probably the field that prevents passage through time from affecting us. The luggage section isn’t protected, though.

You start to say something, but by then I’m pressing a black button, and everything outside will disappear. You look for your house, but it isn’t there. There is exactly nothing there--in fact, there is no there. You are completely outside of time and space, as best you can guess how things are.

You can’t feel any motion, of course. You try to reach a hand out through the field into the nothing around you and your hand goes out, all right, but nothing happens. Where the screen ends, your hand just turns over and pokes back at you. Doesn’t hurt, and when you pull your arm back, you’re still sound and uninjured. But it looks frightening and you don’t try it again.

Then it comes to you slowly that you’re actually traveling in time. You turn to me, getting used to the idea. “So this is the fourth dimension?” you ask.

Then you feel silly, because you’ll remember that I said you’d ask that. Well, I asked it after I was told, then I came back and told it to you, and I still can’t help answering when you speak.

“Not exactly,” I try to explain. “Maybe it’s no dimension--or it might be the fifth; if you’re going to skip over the so-called fourth without traveling along it, you’d need a fifth. Don’t ask me. I didn’t invent the machine and I don’t understand it.”

“But...”

I let it go, and so do you. If you don’t, it’s a good way of going crazy. You’ll see later why I couldn’t have invented the machine. Of course, there may have been a start for all this once. There may have been a time when you did invent the machine--the atomic motor first, then the time-machine. And when you closed the loop by going back and saving yourself the trouble, it got all tangled up. I figured out once that such a universe would need some seven or eight time and space dimensions. It’s simpler just to figure that this is the way time got bent back on itself. Maybe there is no machine, and it’s just easier for us to imagine it. When you spend thirty years thinking about it, as I did--and you will--you get further and further from an answer.

Anyhow, you sit there, watching nothing all around you, and no time, apparently, though there is a time effect back in the luggage space. You look at your watch and it’s still running. That means you either carry a small time field with you, or you are catching a small increment of time from the main field. I don’t know, and you won’t think about that then, either.

I’m smoking, and so are you, and the air in the machine is getting a bit stale. You suddenly realize that everything in the machine is wide open, yet you haven’t seen any effects of air loss.

“Where are we getting our air?” you ask. “Or why don’t we lose it?”

“No place for it to go,” I explain. There isn’t. Out there is neither time nor space, apparently. How could the air leak out? You still feel gravity, but I can’t explain that, either. Maybe the machine has a gravity field built in, or maybe the time that makes your watch run is responsible for gravity. In spite of Einstein, you have always had the idea that time is an effect of gravity, and I sort of agree, still.

Then the machine stops--at least, the field around us cuts off. You feel a dankish sort of air replace the stale air, and you breathe easier, though we’re in complete darkness, except for the weak light in the machine, which always burns, and a few feet of rough dirty cement floor around. You take another cigaret from me and you get out of the machine, just as I do.

I’ve got a bundle of clothes and I start changing. It’s a sort of simple, short-limbed, one-piece affair I put on, but it feels comfortable.

“I’m staying here,” I tell you. “This is like the things they wear in this century, as near as I can remember it, and I should be able to pass fairly well. I’ve had all my fortune--the one you make on that atomic generator--invested in such a way I can get it on using some identification I’ve got with me, so I’ll do all right. I know they still use some kind of money, you’ll see evidence of that. And it’s a pretty easygoing civilization, from what I could see. We’ll go up and I’ll leave you. I like the looks of things here, so I won’t be coming back with you.”

You nod, remembering I’ve told you about it. “What century is this, anyway?”

I’d told you that, too, but you’ve forgotten. “As near as I can guess, it’s about 2150. He told me, just as I’m telling you, that it’s an interstellar civilization.”

You take another cigaret from me, and follow me. I’ve got a small flashlight and we grope through a pile of rubbish, out into a corridor. This is a sub-sub-sub-basement. We have to walk up a flight of stairs, and there is an elevator waiting, fortunately with the door open.

“What about the time machine?” you ask.

“Since nobody ever stole it, it’s safe.”

We get in the elevator, and I say “first” to it. It gives out a coughing noise and the basement openings begin to click by us. There’s no feeling of acceleration--some kind of false gravity they use in the future. Then the door opens, and the elevator says “first” back at us.

It’s obviously a service elevator and we’re in a dim corridor, with nobody around. I grab your hand and shake it. “You go that way. Don’t worry about getting lost; you never did, so you can’t. Find the museum, grab the motor, and get out. And good luck to you.”

You act as if you’re dreaming, though you can’t believe it’s a dream. You nod at me and I move out into the main corridor. A second later, you see me going by, mixed into a crowd that is loafing along toward a restaurant, or something like it, that is just opening. I’m asking questions of a man, who points, and I turn and move off.

You come out of the side corridor and go down a hall, away from the restaurant. There are quiet little signs along the hall. You look at them, realizing for the first time that things have changed.

Steij:neri, Faunten, Z:rgat Dispenseri. The signs are very quiet and dignified. Some of them can be decoded to stationery shops, fountains, and the like. What a zergot is, you don’t know. You stop at a sign that announces: _Trav:l Biwrou--F:rst-Clas Twrz--Marz, Viin*s, and x: Trouj:n Planets. Spej:l reits tu aol s*nz wixin 60 lyt iirz!_ But there is only a single picture of a dull-looking metal sphere, with passengers moving up a ramp, and the office is closed. You begin to get the hang of the spelling they use, though.

Now there are people around you, but nobody pays much attention to you. Why should they? You wouldn’t care if you saw a man in a leopard-skin suit; you’d figure it was some part in a play and let it go. Well, people don’t change much.

You get up your courage and go up to a boy selling something that might be papers on tapes.

“Where can I find the Museum of Science?”

“Downayer rien turn lefa the sign. Stoo bloss,” he tells you. Around you, you hear some pretty normal English, but there are others using stuff as garbled as his. The educated and uneducated? I don’t know.

You go right until you find a big sign built into the rubbery surface of the walk: Miuzi:m *v Syens. There’s an arrow pointing and you turn left. Ahead of you, two blocks on, you can see a pink building, with faint aqua trimming, bigger than most of the others. They are building lower than they used to, apparently. Twenty floors up seems about the maximum. You head for it, and find the sidewalk is marked with the information that it is the museum.

You go up the steps, but you see that it seems to be closed. You hesitate for a moment, then. You’re beginning to think the whole affair is complete nonsense, and you should get back to the time machine and go home. But then a guard comes to the gate. Except for the short legs in his suit and the friendly grin on his face, he looks like any other guard.

What’s more, he speaks pretty clearly. Everyone says things in a sort of drawl, with softer vowels and slurred consonants, but it’s rather pleasant.

“Help you, sir? Oh, of course. You must be playing in ‘Atoms and Axioms.’ The museum’s closed, but I’ll be glad to let you study whatever you need for realism in your role. Nice show. I saw it twice.”

“Thanks,” you mutter, wondering what kind of civilization can produce guards as polite as that. “I--I’m told I should investigate your display of atomic generators.”

He beams at that. “Of course.” The gate is swung to behind you, but obviously he isn’t locking it. In fact, there doesn’t seem to be a lock. “Must be a new part. You go down that corridor, up one flight of stairs and left. Finest display in all the known worlds. We’ve got the original of the first thirteen models. Professor Jonas was using them to check his latest theory of how they work. Too bad he could not explain the principle, either. Someone will, some day, though. Lord, the genius of that twentieth century inventor! It’s quite a hobby with me, sir. I’ve read everything I could get on the period. Oh--congratulations on your pronunciation. Sounds just like some of our oldest tapes.”

You get away from him, finally, after some polite thanks. The building seems deserted and you wander up the stairs. There’s a room on your right filled with something that proclaims itself the first truly plastic diamond former, and you go up to it. As you come near, it goes through a crazy wiggle inside, stops turning out a continual row of what seem to be bearings, and slips something the size of a penny toward you.

“Souvenir,” it announces in a well-modulated voice. “This is a typical gem of the twentieth century, properly cut to 58 facets, known technically as a Jaegger diamond, and approximately twenty carats in size. You can have it made into a ring on the third floor during morning hours for one-tenth credit. If you have more than one child, press the red button for the number of stones you desire.”

You put it in your pocket, gulping a little, and get back to the corridor. You turn left and go past a big room in which models of spaceships--from the original thing that looks like a V-2, and is labeled first Lunar rocket, to a ten-foot globe, complete with miniature manikins--are sailing about in some kind of orbits. Then there is one labeled Wep:nz, filled with everything from a crossbow to a tiny rod four inches long and half the thickness of a pencil, marked Fynal Hand Arm. Beyond is the end of the corridor, and a big place that bears a sign, Mad:lz *v Atamic Pau:r Sorsez.