Finally, I saw a mote of reflected light. When I moved my head within the suit helmet, I realized that the object was tiny and just a few feet in front of us.

“That thing?” I said. “That’s what the mass detector picked up?”

“Of course. What I expected, and what I hoped we’d find.”

He reached out with his gloved left hand. Before I could stop him he gripped the tiny particle between his thumb and forefinger. “As you’d expect,” he said. “It’s tiny, but it should have all the inertia of the original body. Let’s see.”

I saw him pull, but all that did was move his position. “Doesn’t budge,” he said. And then, in a different tone, “This is the damnedest thing. Jeanie, I can’t let go. My finger and thumb won’t come apart — and they hurt.”

He was wearing a tough, insulated suit. Cold or heat could not get through it, nor could radiation. If the suit had somehow developed a hole at finger or thumb, air would be jetting out into space. I saw no tell-tale sign of chilled vapor.

McAndrew turned on his suit jets. It changed his body position only by the length of his own outstretched arm. He was stuck, locked in place by an invisible mote.

I heard his grunt of pain and effort. Suddenly I imagined his father, floating outside the Fafner and with no one to help him, reaching out to touch the mote of compressed matter and held as McAndrew was held.

I still had no idea what was going on, so my next actions were pure instinct. I said, “Grit your teeth, Mac, this is going to hurt worse than it hurts already,” and I took a metal shearing tool from the belt of my suit. Before McAndrew could do anything about it I moved to his suit and severed the top joint of his thumb and first finger.

He cried out in pain as a foam of blood and air spurted from his suit glove. In less than a second the suit sensors reacted and tightened a seal on the fingers. I used the thrustors on my own suit to pull us away toward the Driscoll. As we backed up I saw the first joints of the finger and thumb, still firmly attached to each other. In my over-stimulated condition they seemed to be moving closer to each other and shrinking at the ends.

McAndrew’s suit had decided that he would be better off with a shot of anesthetic. He was still conscious when I hauled us both through the air lock of the Driscoll and peeled off our suits. I put him on a bunk and anxiously examined his left hand.

“How is it, Jeanie?” he said. The painkillers left him rational and quite calm.

“Not too bad. The cuts are clean. But there’s no way to regrow the joints before we’re back home.”

“I’ll manage,” he said. “My own fault. That’s what you get when you don’t think before you act.”

“We’ll be home in less than a week.” I was already at the controls of the Driscoll. “I’ll keep you as comfortable as I can until we get there.”

“Hey, we can’t leave.” He had been lying down, but now he sat suddenly upright. “Not without what we found.”

“We’re certainly not leaving with it. That thing, whatever it is, is lethal.”

“It isn’t, unless you were as careless as I was. Look, I’ll tell you what happened. Then see what you think.”

I paused in setting up our flight home. I looked at the mass detector readings, and confirmed that we were still a full kilometer away from the particle of compressed matter.

“Five minutes to persuade me,” I said.

“It won’t take that long. But you’ll have to take my word on the numbers.”

“I’ll give you that much.” When it comes to calculations, McAndrew doesn’t know how to make mistakes.

“All right.” He lay down again on the bunk and stared up at nothing. “You take a natural body, floating around here in the Asteroid Belt. You go to it, and you place in position there a piece of equipment that locally increases the strong force. Then you turn on the equipment — remotely, from a safe distance. The increase in the strong force makes the body collapse, until it has a density of three billion tons per cubic centimeter. That’s what he claimed he could do, so let’s believe him. If the body you started out with massed eighteen thousand tons, the one you end up with will be minute. About a quarter of a millimeter across.”

“I didn’t have any numbers,” I said, “but I finally guessed that something like that had to be going on. It’s the only way we’d have a strong signal from the mass detector, and not see anything. But you couldn’t escape when you took hold of it, and the pain you felt—”

“My own fault entirely. I didn’t do the other half of the calculation. Gravity’s the weakest force in the Universe, but it follows an inverse square law. Take a mass of eighteen thousand tons, and squeeze it down into a quarter millimeter sphere. What’s the gravity at the surface?”

That sounded like a rhetorical question. I waited.

“The field at the surface of the sphere is thousands of gees.” He held up his damaged hand. “And I was fool enough to grab hold. I couldn’t get my fingers free. Not only that — the field pulled in anything close enough. The material of my glove, then the tips of my finger and thumb. I could feel the blood sucking out.”

“But I didn’t notice a thing,” I protested.

“No more you would. The inverse square law got me, but it saved you. Ten centimeters away from the sphere, the pull is down to a hundredth of a gee — not enough to feel. But close up… good thing you were there to cut me away, or I don’t know what I’d have done.”

I did. I could see it with awful clarity. The same thing would have happened to McAndrew as had happened to Heinrich Grunewald. Held by the tiny ball of compressed matter, unable to move back to the Fafner because of the immense eighteen-thousand ton inertia. Except that at the time it had been not quite eighteen thousand tons. The ball, slowly and inexorably, would have consumed Heinrich, drawing his body little by little into itself. And then, over a much longer time frame, the Fafner must have suffered the same fate. The gentle force of gravity would have tugged it gradually toward the speck of condensed matter, closer and close until there was finally physical contact. From that moment the Fafner was doomed, just as McAndrew’s father had been doomed. As McAndrew himself, without my intervention…

I realized that he was speaking again. “But now we know what happened,” he was saying in an unnaturally cheerful voice, “there’s no danger at all. We’ll bring the compressed matter on board, contain it electromagnetically, and take it back with us to the Institute.”

“Not on this ship you won’t.” The most brilliant mind in the System, but sometimes you wonder if he’s capable of learning anything. Maybe I ought to be charitable and blame the anesthetic. He was starting to sound decidedly woozy. I went on, “Didn’t you tell me, just an hour or two ago, that the compressed matter might be unstable — it could revert unexpectedly to its original condition? Suppose that happened on the way back. Do you want to share your living quarters with an eighteen thousand ton lump of rock?”

“Ah, but I think I see a way around that. If we build the right piece of equipment—”

“You mean when you’ve built the right piece of equipment. After that’s done, and it’s been thoroughly tested, and you know it works in every case and there’s no danger of compressed matter instability, then if you like we’ll come back out here and collect your finger and thumb.”

I wasn’t worried about his finger and thumb, but I didn’t want to say what was really in my mind. Then maybe we’ll be able to give your father a decent burial.

Ignoring McAndrew, I set the final coordinates for home and turned on the drive. The Mighty Mote we were leaving behind was not going to run away. Heinrich Grunewald, in his strangest of sarcophagi, would still be waiting if and when we came back.