Imperial Earth

“It’s made a dozen trips and is getting near saturation, so we’ll soon have to install a new one. Of course it would go on absorbing hydrogen as long as we fed it, but we can’t drag too much unnecessary mass around, or we’ll pay for it in performance. Like the old seagoing ships-they used to get covered with barnacles, and slowed down if they weren’t scraped clean every so often.”

“What do they do with old nodes when they’re too massive to use? Is it true that they’re dropped into the sun?”

“What good would that do? A node would sail right through the sun and out the other side. Frankly, I don’t know what they do with the old ones.

Perhaps they lump them all together into a big granddaddy node, smaller than a neutron but weighing a few million tons.”

There were a dozen other questions that Duncan was longing to ask. How were these tiny yet immensely massive objects handled? Now that Sirius was in free fall, the node would remain floating where it was-but what kept it from shooting out of the drive tube as soon as acceleration started? He assumed that some combination of powerful electric and magnetic fields held it in place, and transmitted its thrust to the ship.

“What would happen,” Duncan asked, “if I tried to touch it?”

“You know, absolutely everyone asks that question.”

“I’m not surprised. What’s the answer?”

“Well, you’d have to open the vacuum seal, and then all hell would break loose as the air rushed in.”

“Then I don’t do it that way. I wear a spacesuit, and I crawl up the drive tunnel and reach out a finger … to

“How clever of you to hit exactly the right spot! But if you did, when your finger tip got within—oh -something like a millimeter, I’d guess-the gravitational tidal forces would start to tear away at it. As soon as the first few atoms fell into the field, they’d give up all their mass-energy-and you’d think that a small hydrogen bomb had gone off in your face. The explosion would probably blow you out of the tube at a fair fraction of the speed of light.”

Duncan gave an uncomfortable little laugh.

“It would certainly take a clever man to steal one of your babies. Doesn’t it ever give you nightmares?”

“No. It’s the tool I’m trained to use, and I understand its little ways. I can’t imagine handling power lasers-they scare the hell out of

me. You know, old Kipling had it all summed up, as usual. You remember me talking about him?”

“Yes.”

“He wrote a poem called “The Secret of the Machines,” and it has some lines

I often say to myself when I’m down here:

“But remember, please, the Law by which we live,

We are not built to comprehend a lie,

We can neither love nor pity nor forgive.

If you make a slip in handling us you die!

“And that’s true of all machines-all the natural forces we’ve ever learned to handle. There’s no real difference between the first caveman’s fire and the node in the heart of the Asymptotic Drive.”

An hour later, Duncan lay sleepless in his bunk, waiting for the Drive to go on and for Sirius to begin the ten days of deceleration that would lead to her rendezvous with Earth. He could still see that tiny flaw in the structure of space, hanging there in the field of the microscope, and knew that its image would haunt him for the rest of his life. And he realized now that Warren Mackenzie had betrayed nothing of his trust; all that he had learned had been published a thousand times. But no words or photos could ever convey the emotional impact he had experienced.

Tiny fingers began to tug at him; weight was returning to Sirius. From an infinite distance came the thin wail of the Drive; Duncan told himself that he was listening to the death cry of matter as it left the known universe, bequeathing to the ship all the energy of its mass in the final moment of dissolution. Every minute, several kilograms of hydrogen were falling into that tiny but insatiable vortex-the hole that could never be filled.

Duncan slept poorly for the rest of the night. He had dreams that he too was Falling, falling into a spinning whirlpool, indefinitely deep. As he fell, he was being crushed to molecular, to atomic, and finally

to sub nuclear dimensions. In a moment, it would all be over, and he would disappear in a single flash of radiation…. But that moment never came, because as Space contracted, Time stretched endlessly, the passing seconds becoming longer… and longer… and longer -until he was trapped forever in a changeless Eternity.

PORT VAN ALLEN

When Duncan had gone to bed for the last time aboard Sirius, Earth was still five million kilometers away. Now it seemed to fill the sky-and it was exactly like the photographs. He had laughed when more seasoned travelers told him he would be surprised at this; now he was ruefully surprised at his surprise.