She didn’t have to decide now. She wanted to finish the letter and get a little sleep. Everything else could wait. She read, If fate is kind, we will meet again soon in a world at peace. If it is less kind, we will meet again though the war goes on. It would have to be very cruel to keep us from meeting again at all. With love and the hope you stay safe-Heinrich.

Ludmila folded the letter small and stuck it in a pocket of her flying suit. Then she took off her leather helmet and goggles, but none of the rest of the outfit, not even her valenki. The inside of the barracks was cold. She lay down on the straw, pulled the blanket up over her head, and fell asleep almost at once.

When she woke the next morning, she found one hand in the pocket where she’d put the letter. That made her smile, and resolved her to answer it right away. Then she had to figure out whether to show it to Schultz. She decided she would, but not this minute. Time enough when they were calmer, not actively angry at each other. Meanwhile, she still had to make her report to Colonel Karpov.

The Nipponese guard handed Teerts his bowl of food. He bowed polite thanks, turned one eye toward it to see what he’d got. He almost hissed with pleasure: along with the rice, the bowl was full of chunks of some kind of flesh. The Big Uglies had been feeding him better lately; by the time he finished the meal, he was almost content.

He wondered what they were up to. Captivity had taught him they were not in the habit of doing gratuitous favors for anybody. Up till now, captivity had taught him they weren’t in the habit of doing any favors whatever. The change made him suspicious.

Sure enough, Major Okamoto and the usual stone-faced, rifle-toting guard marched up to the cell door not long after the bowl was taken away. As the door swung open, Okamoto spoke in the language of the Race: “You will come with me.”

“It shall be done, superior sir,” Teerts agreed. He left the cell with no small relief. His step seemed lighter than it had in a long time; going upstairs to the interrogation chamber of the Nagasaki prison felt like good exercise, not a wearing burden. Amazing what something close to proper food can do, he thought.

Again, the Nipponese inside the chamber wore the white robes of scientists. The Big Ugly in the center chair spoke. Major Okamoto translated: “Dr. Nishina wishes to discuss today the nature of the bombs with which the Race destroyed the cities of Berlin and Washington.”

“Why not?” Teerts answered agreeably. “These bombs were made from uranium. In case you do not know what uranium is, it is the ninety-second element in the periodic table.” He let his mouth fall slightly open in amusement. The Big Uglies were so barbarous, they would surely have not the slightest notion of what he was talking about.

After Okamoto relayed his answer to the Nipponese scientists, he and they talked back and forth for some time. Then he returned his attention to Teerts, saying, “I do not have the technical terms I need to ask these questions in proper detail. Give them to me as we speak, please, and do your best to understand even without them.”

“It shall be done, superior sir,” Teerts said, agreeable still.

“Good.” Okamoto paused to think; his rubbery Big Ugly features made the process easy to watch. At length, he said, “Dr. Nishina wishes to know which process the Race uses to separate the lighter, explosive kind of uranium from the more common heavy kind.”

Teerts bit down on that as if it were an unsuspected bone in his meat. Not in his wildest nightmares-and he’d had some dreadful ones since his capture-had he imagined that the Big Uglies had the slightest clue about atomic energy, or even that they’d heard of uranium. If they did-He abruptly realized they might be dangerous to the Race, not just the horrid nuisances they’d already proved themselves.

To Major Okamoto, he said, “Tell the learned Dr. Nishina that I do not know which processes he means.” He had to work not to turn an eye turret toward the instruments of torture in the interrogation chamber.

Okamoto fixed him with a stare he’d come to identify as hostile, but passed his words on to Nishina without comment. Nishina spoke volubly in reply, ticking off points on his fingers as If he were a male of the Race.

When he was through, Okamoto translated: “He says theory shows several ways which might accomplish this. Among them are successive barriers to a uranium-containing gas, heating the gas so that part of it which has the lighter kind of uranium rises more than the other, using a strong electromagnet”-a word that took a good deal of backing and filling to get across-“and using rapid spinning to concentrate the lighter kind of uranium. Which of these does the Race find most efficient?”

Teerts stared at him. He was even more appalled than he had been when his killercraft got shot down. That had affected only his own fate. Now he had to worry about whether the Race had any idea what the Tosevites were up to. They might be barbarians-by everything Teerts had seen, they were barbarians-but they were also alarmingly knowledgeable… which meant it behooved Teerts to be more than cautious in his answers. He’d have to do his best to avoid giving away any information at all.

He took so long figuring that out that Okamoto snapped, “Don’t waste time dreaming up lies. Answer Dr. Nishina.”

“I beg your pardon, superior sir,” Teerts said, and added, “Gomen nasai-so sorry,” from his limited stock of Nipponese. “Part of the problem is my not having enough words to give a proper answer, and another part is my own ignorance, for which I again beg pardon. You must remember that I am-I was-a pilot. I had nothing at all to do with uranium.”

“You certainly were glib enough talking about it a little while ago,” Okamoto said. “You do not want to make me disbelieve you. Some of the tools back there are very sharp, others can be made hot, and still others can be hot and sharp at the same time. Do you want to learn which is which?”

“No, superior sir,” Teerts gasped with utmost sincerity. “But I truly am ignorant of the knowledge you seek. I am only a pilot, not a nuclear physicist. What I know of flying, I have freely told you. I am not an expert in the matter of atomic weapons. What little I know of nuclear energy I learned in school as I was growing from hatchlinghood. It is no more and no less than any other ordinary male of the Race would know.”

“This is difficult to believe,” Okamoto said “You spoke quite a lot about uranium just a little while ago.”

That was before I realized how much you knew about it, Teerts thought. He wondered how he was going to escape with his integument intact. He knew he couldn’t lie to the Nipponese; he didn’t know how much they knew, and the only way to find out-getting caught-would involve the painful penetration of that integument.

He said, “I do know that atomic weapons do not necessarily use uranium alone. Some involve, I am not sure how, hydrogen as well-the very first element.” Let the Japanese chew on that paradox for a while, he thought: how could a weapon involve the lightest and heaviest elements at the same time?

After Okamoto interpreted, the team of Big Ugly scientists chattered for a while among themselves. Then Nisbina, who seemed to be their spokesman, put a question to Okamoto. The major translated for Teerts: “The uranium explosion, then, is hot enough to make hydrogen act as it does in the sun and convert large amounts of matter to energy?”

Horror filled Teerts. Every time he tried to escape from this hideous mess in which he found himself, he sank deeper instead. The Big Uglies knew about fusion. To Teerts, the product of a civilization that grew and changed at a glacial pace, knowing about something was essentially the same as being able to do it. And If the Tosevites could make fusion bombs…