Boranova (Morrison glanced over his left shoulder) seemed oblivious to the exchange. She was busy with her instrument and Morrison wondered what she could be so intent on, considering that the ship's engines were off and they were merely drifting with the current.

As for Dezhnev - with the engines off - he was the one crew member who, in truth, had nothing to do at the moment (except to keep half an eye at the material up ahead in case of an unexpected emergency).

He said, "Come, Albert, study the skeptic waves and give us some answers. Then we can leave this place. It's extremely exciting being inside a cell for those who like it, but already I am quite certain I have seen enough. My father used to say: 'The most exciting part of any trip is reaching home again.'"

Boranova said, "Arkady -"

"Yes, Natasha."

"Save a few words for tomorrow." Morrison noticed the trace of a smile on her lips.

"Certainly, Natasha. I suspect an attempt at sarcasm, but I shall do as you say." And though he snapped his mouth shut with an exaggerated click of his teeth, he began to hum very quietly to himself, a tune in the minor mode.

Morrison felt a little astonished. They had been in the ship now for a little less than five hours - but it felt the equivalent number of days, perhaps years. Yet, unlike Arkady and despite his earlier feelings of terror, he was not ready to leave Shapirov's body. He felt a strong urge to explore the cell and his thoughts rested on the possibility.

Kaliinin must have been thinking along similar lines, for she said in a soft, introspective tone, "What a shame to be the first people inside the most complex of all living cells and to do nothing at all about investigating it properly."

"That is exactly -" began Morrison, then thought better of it and let the words dangle.

Konev swung his arm as though he were driving off hordes of insects. "I can't understand this. We are in the cell and we came here for a specific purpose. Albert, focus on the skeptic waves."

"I am doing so," said Morrison sharply. "In fact, I have done so. - Look!"

Konev twisted his head, then unclasped himself, so that he could turn around and peer over the back of his seat. He stared at Morrison's small screen and said, "The waves seem sharper."

"They are sharper. They're more intense and they show finer oscillations than I've ever seen. Come to think of it, I wonder how fine they can get. Sooner or later, an oscillation, if fine enough, will represent the wobbling of a single electron - and then we have to take into account the uncertainty principle."

"You forget. We're miniaturized and Planck's constant is nine orders of magnitude smaller for us than it is under standard conditions."

"You forget," protested Morrison, eager to catch the other in a misstep this time, "that the waves are reduced by that much before they reach us. Those waves are exactly where they should be relative to the uncertainty principle, therefore."

Konev hesitated a bare moment. "It doesn't matter. We're looking at something now and there's no perceptible uncertainty blurring. What does it mean?"

"It supports my theory," said Morrison. "This is exactly what I ought to see inside a cell if my interpretation of skeptic wave activity is correct -"

"That's not what I mean. We began with the assumption that your theory was correct. Now it's no longer an assumption, it's a demonstrated fact, and I congratulate you. But what does it mean? What do those skeptic waves show Shapirov to be thinking?"

Morrison shook his head. "I have no data - zero data - on the correlation of such waves and specific thoughts. It would take years to gather such a correlation, if it could be done at all."

"But perhaps the skeptic waves, when this clear and intense, produce an inductive effect on your brain. Are you getting any of your famous images?"

Morrison thought for a moment, then shook his head, "None!"

From behind him came a quiet voice, "I'm getting something, Albert."

Morrison turned. "You, Natalya?"

"Yes, it's odd - but I am."

Konev demanded, "What are you getting, Natalya?"

Boranova hesitated, concentrating. "Curiosity. Well, it's not exactly an image of anything. Just an impression. I feel curiosity."

"And so you might," said Morrison. "It needs no impression from outside to produce such a feeling under these circumstances."

"No no. I know what my own thoughts and impressions are like. This is imposed from outside."

Morrison said, "Do you feel it right now?"

"Yes. It comes and goes a little, but I feel it right now."

"All right. What about now?"

Boranova looked surprised. "It stopped suddenly. - Did you turn off your machine?"

"I turned it down. Now, you tell me when you feel the sensation and when you don't." He turned to look at Kaliinin, intending to tell her to say or do nothing that would indicate when he turned the machine down or up, but she was staring out at the cell, obviously lost in the marvel of watching the interior of a neuron. He wondered if, at the moment, she heard - or cared - what was going on.

He turned away and said, "Natalya, close your eyes and concentrate. Just say 'on' when you get the sensation and 'off` when you don't."

For several minutes, she complied with his suggestion.

Morrison said to Konev, "Does the machine make a noise when it is turned down or up? Is there anything you can hear or sense?"

Konev shook his head. "I'm not aware of anything."

"Then there's no mistake. She's getting the sensation only when the machine is on."

Dezhnev, who, unlike Kaliinin, had followed everything, said. "But why?" His eyes narrowed. "The brain waves are there whether your machine detects them or not. She should get the feeling of curiosity all the time."

"No no," said Morrison. "My device filters out all the components but the actual skeptic waves. Without the machine, she just gets a confused mass of sensations, responses, correlations, and miscellany of all kinds. With the machine, she gets only the skeptic waves, which further demonstrates the usefulness of my theory."

"I don't get anything at all," said Dezhnev, frowning. "Doesn't that destroy your theory?"

Morrison shrugged. "Brains are complicated mechanisms. Natalya gets it. You don't. For that matter, neither do I. Maybe this particular skeptic wave component fits something in Natalya's brain, not in ours. I'm not going to be able to explain everything at once. - Do you get anything, Konev?~

"No," he answered, as discontented as Dezhnev had been. "Yet I obtained impressions when we were outside the neuron."

Morrison shook his head and said nothing.

Konev burst out, "Can't you get anything but just a vague feeling of curiosity, Natalya?"

Boranova, "No, Yuri, I can't. Not at this moment. But you remember Pyotr Shapirov. He was curious about everything."

"I remember, but that doesn't help. Albert, in what direction are we moving?"

Albert said, "Downstream. It's the only direction in which we can move."

"No no." Then, in sudden anger, "Is that a joke? Are you trying to be funny?"

Morrison said, "Not at all. You asked in what direction we were going. What other answer could I have given you? Surely the compass directions have no meaning here."

Konev said, "All right. Sorry. The stream goes this way here. On the other side of the cell, it goes the other way. It's a circulation. But the nerve impulse goes one way only, from the dendrites to the axon. Are we on the side of the cell that's taking us in the same direction as the nerve impulse or in the other direction?"

"Does it matter?" said Morrison.

"I think it does. Can your device tell you in which direction the impulse is traveling?"

"Yes, certainly. There should be a slight shift in the shape of the waves, depending on whether they are meeting the device head-on or from the rear."