Fantastic Voyage II: Destination Brain

Chapter 14. Axon

Morrison bristled at Konev's order. (It had definitely been that.)

He indicated his resentment by refusing to respond at all for a while. He continued to stare out into the interior of the neuron and could distinguish nothing he recognized. He could see fibers, convoluted plates, hulks of uncertain size and of no clear shape. What's more, he had a strong feeling that there was a skeletal presence in the cell that held the larger objects - the organelles - in place, but that the ship was slipping past it all too quickly, as though it were in a river racing downstream. The feeling of motion was far stronger here than in the bloodstream, for though there were small objects (debris?) that moved along with them, there were larger objects that apparently remained in place and that they passed rapidly.

Finally Morrison said, "Look, Yuri, we're moving so quickly that the motion is likely to distort the skeptic waves badly."

Konev snarled, "Are you mad? We're not moving quickly at all. We're just drifting with the intracellular stream that serves to make certain that the small molecules are all made available to the organelle structure of the cell. The movement is very slow on the normal scale; it seems fast only on our miniaturized scale. Do I have to teach you cellular physiology?"

Morrison bit his lips. Of course. He had again forgotten how miniaturization distorted his perception. And again Konev was completely right.

"It might be better, though," said Morrison, fighting for self-respect, "if we changed back to D-glucose and allowed an enzyme to snatch us up. The combined size would slow us down and make it easier to pick up the waves."

"We don't have to slow down. The nerve impulse travels at a minimum of two meters per second in real velocity and in apparent velocity at our size that's about seventy times the real speed of light. As compared with that, our speed, however great it seems, is trivial. Even if we are moving at the apparent speed of a rocket ship, to the nerve impulse we seem virtually motionless."

Morrison lifted his arm in surrender and felt furious with Konev. There was such a thing as being too right. He cast a quick sidewise glance at Kaliinin, with the uncomfortable feeling that she would be showing her contempt. She met his glance soberly and with no trace of a sneer. In fact, her shoulders lifted slightly as though to say (Morrison imagined), "What do you expect of a savage?"

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."

"And?"

"And we're moving in the direction of the impulse."

"Good! A stroke of luck. We're heading for the axon, then."

"So it would seem."

Boranova said, "And if we are heading for the axon?"

Konev said, "Natalya, think! The skeptic waves travel along the surface of the cell. The cell here is wide and relatively large. The skeptic waves spread out over a large surface and are weakened in intensity. As the cell approaches the axon, it narrows. The axon itself is long, a very long tube compared to the cell - and very narrow. The waves must concentrate enormously as they race along that tube and they must grow more intense. What's more, the axon is insulated by a thick myelin sheath, so that the wave energy will not be lost to the outside, but will be kept tightly within the axon."

Boranova said, "You think, then, that we can receive more effectively in the axon?"

"Much more effectively. If you can detect curiosity now, it should be overwhelming in the axon. And you might be able to detect what Shapirov is curious about."

"It may turn out to be totally unimportant," said Morrison thoughtfully. "What if he's curious about why he should be lying there and not moving?"

"No," said Konev sharply, "that would not interest him. I knew Shapirov well. You didn't."

Morrison nodded. "That's true enough."

"All his waking time was consumed with the miniaturization process," said Konev. "All his dreams, too, I suspect. And toward the end, in the last few weeks before the - the accident took place, he was working, thinking, dreaming of the connection between quantum and relativity, thinking of how to make miniaturization and deminiaturization energy-free and stable."

"Surely," said Morrison, "if that were the case, he must have given some hints as to some of the details of his thinking."

"No, he was a child in some ways. We knew what he was thinking of, but not whether he was making progress or in what direction. What he loved to do was to present it to us whole, complete. - Remember, Natalya, how he loved to do that? He did that with miniaturization itself. When he finally wrote his paper - it was a young book -"

Morrison said casually, "Where was it published?"

Konev sneered. "You know it wasn't published. It had a limited circulation to those who had to know. It's nowhere where you're likely ever to see it."

Boranova said, "Yuri, don't be needlessly insulting. Albert is a fellow crew member and a guest. He is not to be treated as a spy."

Konev said, "If you say so, Natalya. Nevertheless, if Shapirov is curious, so intensely curious that Natalya gets that message, it can be only about the quantum-relativity connection. If we can get some details about that, any details at all, we'll have a starting point and can continue."

"And you think we'll get those details in the axon?"

"Yes, I'm sure of it." Konev clenched both fists as though preparing to get a stranglehold on the facts.

Morrison looked away. He was not sure of it. Increasingly, it was beginning to look to him as though matters were moving in another direction altogether and that that was just as well-

He tried not to show it, but he was as excited as Konev was.

Dim objects to either side loomed up ahead, drifted to one side, left or right, and fell behind. Ribosomes? Golgi apparatus? Fibrils of one sort or another? Morrison could not tell. From the vantage point of small molecule size, nothing, not even the sharpest, most familiar intracellular object, would look familiar, let alone recognizable.

They were racing through a strange land of indefiniteness and Morrison could not, no matter how he tried, picture his surroundings as those with which he was familiar from electron micrography.

He wondered if, somewhere beyond where the light of the ship's beam extended, there would be the endless volume of the cell's nucleus. Imagine being within submicroscopic distance of it and yet never seeing it.

He concentrated on the immediate surroundings. It seemed to him, once again, that he ought to make out the water molecules that made up 98 percent of all the molecules in the cell, that huge percentage being the direct consequence of the fact that they were just about the smallest molecules there.

He could not be sure. Focus his eyes though he did and as tightly as he could, what he saw was only a faint glitter - a photon, perhaps, bouncing off such a molecule and flashing back toward his eye. At best, he would only see one or two from any given water molecule.

He was suddenly aware of Kaliinin's head, bending toward his. Her hair brushed his face and he noticed, as he had once or twice before, the fresh scent of her shampoo.

She said, "This is terrible, Albert."

Her breath was a little strong and Morrison flinched before he could stop himself.

She noticed, for her fingers came up sharply, covering her mouth, and she mumbled, "I'm sorry."

Morrison shook his head slightly, "My own breath isn't exactly a bed of roses. - Tension, nothing much to eat. A drink of water might help, Natalya."

One drink set off everybody, of course, in a chain reaction.

Kaliinin fingered a small white pellet. "Peppermint drop?"

Morrison held out his hand and smiled. "Is it permitted?"

Kaliinin's eye flickered back toward Boranova and she gave a Who-cares shrug. Having passed the drop to Morrison, Sophia popped another in her mouth.

Then she said again, "This is terrible, Albert."

"What is, Sophia?"

"How can we pass through this cell without examining it in detail?"

"We have a specific mission."

"Yes, but no one may be back within a brain cell for many years. Perhaps, never. When, in the future, someone will read that this ship and this crew merely raced through, looking neither to right or left, what barbarians they will think we must have been."

She was whispering very softly and their heads were bent close together. Morrison found himself rather enjoying it.

Had he grown so calloused to the threat of the situation - the constant skirting along the edge of the abyss of spontaneous deminiaturization, the possibility of split-second death at any moment - that he could take joy from the trivial fact that his lips were so close to the pretty face of a woman?

Well, why quarrel with that? Let the nearness anesthetize him, so that he might for a moment forget.

Morrison remembered the sharp image he had had so brief a time before of a happy, smiling, beautiful girl. He had not recognized the thought as his own, so unexpectedly had it come out of nowhere, and it didn't return, even now, but he remembered it distinctly and the memory squeezed at his heart with a warm feeling.

He had the momentary impulse to kiss her lightly, just a touch upon the cheekbone with his lips - and fought it down. If she decided to take it amiss, he would feel like an incredible fool.

Morrison said gently, "The people of the future will know we have a mission. They will understand."

"I wonder," Sophia said, then paused and sent a quick and almost fearful look in the direction of Konev, who as always sat stiff and detached at ally sign of speech or even motion from Kaliinin.

She turned to her computer, switched it to the word-processor mode, and tapped out in rapid Russian: YURI IS A FANATIC WHO SACRIFICES EVERYTHING TO HIS MANIA. THERE IS NO CHANCE OF READING THOUGHTS, BUT HE PERSUADES EVERYONE. She blanked it, then tapped out: WE ARE HIS VICTIMS and blanked it at once.

For "we," read "I," thought Morrison sadly. He looked at his own instrument hesitantly. It seemed to him that the thought waves, which he had dimmed to low, were growing more intense. Morrison looked out as though he might be able to tell just how near the axon they now were, but, of course, there was no way of knowing.

He blanked the radiation, switched to word-processing, and printed out in Roman-lettered Russian: HE, TOO, IS HIS VICTIM.

Kaliinin at once printed savagely: NO. I DON'T BELIEVE PEOPLE ARE THEIR OWN VICTIMS.

Morrison thought sadly of his one-time wife, his two children, his own inability to present his theory persuasively, or, alternatively, to walk away from it, and tapped out: I BELIEVE WE ARE EACH OF US MORE A VICTIM OF OURSELVES THAN OF ANYONE ELSE and returned it quickly to the thoughtwave mode.

He sucked in his breath sharply. The waves on his screen had risen high in intensity despite the fact that the device was still at low.

Morrison opened his mouth to comment on the fact, but Dezhnev made that unnecessary. "Yuri," he said, "the cell membrane is curving in and we're curving in with it."

That would account for it, thought Morrison. The cell was narrowing in toward the axon and the skeptic waves were being enormously concentrated. His device, having filtered out everything else, would radiate the wave function of the skeptic waves throughout the interior of the ship. And with what results?

Konev said with delight, "We'll see what happens now. Albert, keep your machine working at top intensity."

Boranova said, "I hope that whatever happens gives us our answer or at least a start to our answer. I have grown tired waiting."

"I don't blame you," said Dezhnev. "As my father used to say: 'The longer it takes to get to a point, the blunter it turns out to be.'"

It seemed to Morrison that every line of Konev's stiff body now betokened excitement and expectant triumph - but Morrison did not join in that expectation.

Morrison stared outward. They were well into the axon now and being carried along it by the fluid stream within the cell.

In the real world, the axon was an excessively thin fiber, but in the microminiaturized world of the ship, it might be the equivalent of a hundred kilometers across. As for its length, it was much, much longer than the cell itself. Going from one end to the other of the axon might very well be the equivalent of a trip from the Earth to the moon and back a couple of dozen times over. On the other hand, their apparent speed on the microminiaturized scale must seem, to themselves, to be a respectable faction of the speed of light.

There was no indication of that incredibly rapid speed, however. The ship was moving with the current and there was far less in the way of macromolecules or organelles in the axon than there had been in the cell body. If there were structural fibers withstanding the current and remaining motionless with respect to the cell membrane, the current swept them past those too rapidly for them to be visible, even if a sizable number of photons were reflected from them - which, of course, they were not.

So he gave up. There was nothing to look at outside.

He ought, in any case, to be looking at his screen. The skeptic waves were becoming even more intense, he could see. It had grown difficult to wipe out the nonskeptic material. It was so strong that it flooded the computer's receiving capacity.

What's more, the tight, elaborate vibration of the skeptic waves had become a series of irregular spikes. Even at full expansion, it was clear he wasn't getting all the detail that existed. Morrison had a clear vision of the necessity of a laser printout clear enough to be placed under a microscope.

Konev had unclasped himself and had half-lifted himself over the back of his seat so that he might stare at the screen.

He said, "I haven't seen it like that before."

Morrison replied, "Nor have I and I have been studying skeptic waves for nearly twenty years. Nothing like this."

"I was right, then, about the axon?"

"Absolutely, Yuri. The waves have concentrated themselves beautifully."

"And the meaning, then?"

Morrison spread out his hands helplessly. "There you have me. Since I have never seen anything like this, I obviously can't interpret it."

"No no," said Konev impatiently. "You keep concentrating on the screen and I keep thinking about induction. Our own minds are the true receptors - by way of your machine. What do you receive? Images? Words?"

"Nothing," said Morrison.

"That's impossible."

"Are you getting anything?"

"It's your machine. Adjusted to you."

"You've had images before, Yuri."

Dezhnev's voice broke in dryly, "My father used to say: 'If you want to hear, you must begin by listening.'"

Boranova said, "Dezhnev Senior is correct. We can receive nothing if we fill our minds with contention and shouts."

Konev drew a deep breath and said with a softness that was most uncharacteristic of him, "Very well, then, let us concentrate."

An unnatural quiet fell over the ship's crew.

Then Kaliinin said, breaking the silence rather timidly, "There is no time."

"No time for what, Sophia," said Boranova.

"I mean that's the phrase I sensed: 'There is no time.'"

Morrison said, "Are you saying that you received it from Shapirov's skeptic waves?"

"I don't know. Is that possible?"

Boranova said, "A moment before I had the same thought. It occurred to me that a better way of tackling the problem might be to study the recorded skeptic waves on the screen and to wait for sudden changes. It might be the change of pattern rather than the pattern itself that would produce an image. But then I thought that the waiting might be an enormously long drawn-out affair and for that we lacked the time."

"In other words," said Morrison, "you thought, 'There is no time.'

"Yes," said Boranova, "but it was my own thought."

"How can you know, Natalya?" said Morrison.

"I know my own thoughts."

"You also know your own dreams, but sometimes dreams arise out of external stimuli. Suppose you receive the thought 'There is no time.' Because you are not accustomed to receiving thoughts, you quickly build up a line of free association that makes it reasonable for you to feel that you have had the thought yourself."

"That may be so, but how does one tell, Albert?"

"I'm not sure, but Sophia apparently sensed the same phrase and we might ask if she were thinking something independently that would give rise to the phrase as a matter of course."

"No, I was not," said Kaliinin. "I was trying to keep my mind empty. It just came in."

"I didn't sense anything," said Morrison. "How about you, Yuri?"

Konev shook his head, frowning ferociously at his failure. "No, I didn't."

"In any case," said Morrison thoughtfully, "it needn't mean anything. Natalya felt it might be an idle thought that arose out of a series of previous thoughts in a natural way and with none but the most superficial meaning. Even if the thought had arisen in Shapirov's mind, it might be equally superficial there."

"Perhaps," said Konev, "but perhaps not. His whole life and mind were bound up in the problems of miniaturization. He would be thinking of nothing else."

"You keep saying that," said Morrison, "but, actually, that is romantic nonsense. No one thinks of nothing else. The most lovesick Romeo in history could not concentrate on his Juliet forever. A twinge of colic, a distant sound, and he would be distracted at once."

"Nevertheless, we must take anything Shapirov says as possibly significant."

"Possibly," said Morrison. "But what if he were trying to work out the extension of the miniaturization theory and decided to moan he had no time, that there was insufficient time to complete his work?"

Konev shook his head, more, it seemed, to brush off distraction than in a clear negative. He said, "How about this? What if it seemed to Shapirov that any miniaturization that involved an increase in the speed of light proportional to the decrease in Planck's constant would involve a change that was instantaneous, that took no time. And, of course, as the speed of light increased vastly, so would the inevitable speed of a massless - or nearly massless - object. He would, in effect, abolish time and could say to himself proudly, 'There is no time.'"

Boranova said, "Very farfetched."

"Of course," said Konev, "but worth thinking about. We must record every impression we get, however dim, however apparently meaningless."

"I plan to do precisely that, Yuri," said Boranova.

Konev said, "Then quiet again. Let's see if we can get anything more."

Morrison concentrated fiercely, his eyes half-buried under jutting eyebrows, but those same eyes were fixed on Konev, who sighed and said in a whisper, "I get something over and over - 'nu times c equals m sub s.'"

Morrison said, "I got that, too, but I thought it was 'm times c square.'

"No," said Konev tightly. "Try again."

Morrison concentrated, then, quite abashed, said, "You're right. I get it, too: 'nu times c equals m sub s.' What does it mean?"

"Who can say at first glance? However, if this is in Shapirov's mind, it means something. We can assume that nu is radiational frequency, c the speed of light, and m sub s is the standard mass - that is, the mass at rest under ordinary conditions. In the light of -"

Boranova's arms lifted with an admonitory forefinger upraised. Konev stopped short and said uncomfortably, "But that is neither here nor there."

Morrison grinned, "Classified material, eh, Yuri?"

And then Dezhnev's voice sounded with an unaccustorned petulance to it. "How is it," he said, "that you are hearing all these things about time and standard mass and whatnot and I sense nothing? Is it that I am not a scientist?"

Morrison said, "I doubt that that has anything to do with it. Brains are different. Maybe they come in different types the way blood does. Blood is blood but you can't always transfuse one person's blood into another. Your brain may be sufficiently different from Shapirov's so that there is no sensory crossover."

"Only mine?"

"Not only yours. There may be billions of minds that can pick up nothing from Shapirov. You'll notice that Sophia and Natalya can pick up the same things, which Yuri and I cannot - and vice versa."

"Two men and two women," grumped Dezhnev, "and I am what?"

Konev said impatiently, "You are wasting our time, Arkady. Let's not endlessly discuss every tiny thing we pick up. We have more to hear and little time to do it in. If you concentrate a little harder, Arkady, you, too, may sense something."

Silence!

It was broken occasionally by a soft murrnur from one or another who reported sensing an image or a scrap of words. Dezhnev contributed only one thing: "I sense a feeling of hunger, but it may be my own."

"Undoubtedly," said Boranova dryly. "Console yourself with the thought, Arkady, that when we get out of here, you will be allowed seconds and thirds of every dish and unlimited vodka."

Dezhnev grinned almost lasciviously at the thought.

Morrison said, "We don't seem to come across anything mathematical or even out of the ordinary. I insist that even Shapirov must have the great majority of his thoughts concerned with trivia."

"Nevertheless," grunted Konev under his breath, "we listen."

"For how long, Yuri?"

"Till the end of the axon. Right down to the end."

Morrison said, "Do you then intend to run into the synapses or will you double back?"

"We will go as close to the synapses as possible. That will bring us into the immediate neighborhood of the adjoining nerve cell and the skeptic waves may be even more easily sensed at that crucial point of transfer than anywhere else."

Dezhnev said, "Yes, Yuri, but you are not the captain. - Natasha, little flower, is that what you wish, too?"

Boranova said, "Why not? Yuri is right. The synapse is a unique spot and we know nothing about it."

"I ask only because half our power supply has now been consumed. How long dare we continue to remain within the body?"

"Long enough," said Boranova, "to reach the synapse, certainly."

And silence fell once more.

The ship continued to move along the enormous length of the axon and Konev dictated the actions of the others more and more.

"Whatever you get, report. It doesn't matter whether it makes sense or not, whether it's one word or a paragraph. If it's an image, describe it. Even if you think it's your own thought, report it if there's the slightest doubt."

"You'll have meaningless chatter," said Dezhnev, apparently still annoyed at his nonreceiving brain.

"Of course, but two or three meaningful hints will pay all. And we won't know what's meaningful until we examine everything."

Dezhnev said, "If I sense something I think isn't mine, do I throw it in, too?"

"You, especially," said Konev. "If you're as insensitive as you seem to think, anything you do get may be particularly important. Now, please, no more talk. Every second of conversation may mean we miss something."

And there began a period of disjointed phrases out of which, in Morrison's opinion, it was impossible to make sense.

One surprise came when Kaliinin said suddenly, "'Nobel Prize!'"

Konev looked up sharply and almost responded - then, as though realizing who had said it, he subsided.

Morrison said, trying not to sound mocking, "Did you get that, too, Yuri?"

Konev nodded. "At almost the same time."

"That's the first crossover between a man and woman," said Morrison. "I suppose Shapirov had his mind on it in connection with his extension of miniaturization theory."

"Undoubtedly. But his Nobel Prize was sure for what he had already done in miniaturization."

"Which is classified and therefore unknown."

"Yes. But once we perfect the process, it will no longer be unknown."

"Let's hope so," said Morrison sardonically.

Konev snapped, "We are no more secretive than you Americans."

"All right. I'm not arguing," but Morrison grinned broadly at Konev, who was peering over his shoulder at him, and that seemed to irritate the younger man even further.

At one point, Dezhnev said, "'Hawking.'"

Morrison's eyebrows lifted in surprise. He had not expected this.

Boranova said, looking displeased, "What is this, Arkady?"

"I said, 'Hawking,'" said Dezhnev defensively. "Out of nowhere it popped into my mind. You told me to tell you anything that did."

"It is an English word," said Boranova, "that means 'spitting.'

"Or 'selling,'" said Morrison cheerfully.

Dezhnev said, "I don't know enough English to know that word. I thought it was someone's name."

"So it was," said Konev uncomfortably. "Stephen Hawking. He was a great English theoretical physicist of over a century ago. I was thinking of him, too, but I thought it was my own thought."

Morrison said, "Good, Arkady. That might be useful."

Dezhnev's face split with a grin. "I'm not altogether useless, then. As my father used to say: 'If the words of a wise man are few, they are nevertheless worth listening to.'"

An interminable half hour later, Morrison said gently, "Are we getting anywhere at all? It seems to me that most of the phrases and images tell us nothing. 'Nobel Prize' tells us, reasonably enough, that Shapirov thought of winning one, but we know that. 'Hawking' tells us that that physicist's work was significant, perhaps, in connection with the extension of miniaturization, but it doesn't tell us why."

It was not Konev who rose to the defense, as Morrison would have expected, but Boranova. Konev, who might have been readying himself for a response, seemed willing, on this occasion, to let the captain bear the weight.

Boranova said, "We are dealing with an enormous cryptogram, Albert. Shapirov is a man in a coma and his brain is not thinking in a disciplined or orderly fashion. It is sparking wildly, those parts of it that remain whole, perhaps randomly. We collect everything without distinction and it will all be studied by those of us with a deep understanding of miniaturization theory. They may see meaning where you see none. And a bit of meaning, in one corner of the field, may be the start of an illumination that will spread to all parts of it. What we are doing makes sense and it is the proper thing to do."

Konev then said, "Besides, Albert, there is something else we can try. We are approaching a synapse. This axon will end eventually and split up into many fibers, each of which will approach but not join with the dendrite of a neighboring neuron."

"I know that," said Morrison impatiently.

"The nerve impulse, including the skeptic waves, will have to jump the tiny gap of the synapse and, in doing so, the dominant thoughts will be less attenuated than the others. In short, if we jump the synapse, too, we will reach a region where we may, for a while at least, detect what we want to hear with less interference from trivial noise."

"Really?" asked Morrison archly. "This notion of differential attenuation is new to me."

"It's the result of painstaking Soviet work in the area."

"Ah!"

Konev fired up at once, "What do you mean, 'Ah!'? Is that a dismissal of the value of the work?"

"No no."

"Of course it is. If it's Soviet work, it means nothing."

"I just mean that I haven't read or heard anything about it," Morrison said in defense."

"The work was done by Madame Nastiaspenskaya. I presume you've heard of her."

"Yes, I have."

"But you don't read her papers, is that it?"

"Yuri, I can't keep up with the English-language literature, let alone with -"

"Well, when this is over, I'll see that you get a collection of her papers and you may educate yourself."

"Thank you, but may I say that on the face of it I think the finding is an unlikely one. If some types of mental activity survive a synapse better than others, then, considering that there are many hundreds of billions of synapses in the brain, all constantly in use, the final result would be that only a tiny proportion of thoughts would survive at all."

"It's not as simple as that," said Konev. "The trivial thoughts are not wiped out. They continue at a lower level of intensity and don't decline indefinitely. It's just that, in the immediate neighborhood of a synapse, the important thoughts are, for a time, relatively strengthened."

"Is there evidence for this? Or is it only a suggestion?"

"There's evidence of a subtle nature. Eventually, with miniaturization experiments, that evidence will be hardened, I'm sure. There are some people among whom this synapse effect is much stronger than average. Why else can creative individuals concentrate so hard and so long, if they are not less distracted by trivia? And why, on the contrary, are brilliant scholars traditionally absentminded?"

"Very well. If we find something, I won't quarrel with the rationale."

Dezhnev said, "But what happens when we come to the end of the axon? The stream of fluid we're riding will just make a U-turn at that point and carry us back again against the opposite wall of the axon. Do I force my way through the membrane?"

"No," said Konev. "Of course not. We'd damage the cell. We'll have to take on the electric charge pattern of acetylcholine. That carries the nerve impulse pattern across the synapse."

Boranova said, "Sophia, you can give the ship an acetylcholine pattern, can't you?"

"I can," said Kaliinin, "but aren't the acetylcholine molecules active on the outside of the cell?"

"Nevertheless, the cell may have a mechanism for ejecting them. We'll try."

And the trip along the seemingly endless axon continued.

Suddenly the end of the axon was in sight. There was no hint, no warning. Konev noticed it first. He was watching and he knew what he was watching for, but Morrison gave him full credit. He himself was watching, too, and knew what he was watching for, and yet did not see it when it came.

To be sure, Konev was in the front seat, while Morrison had to stare past Konev's head. That was not much of an excuse either.

In the curiously ineffective light of the ship's beacon, it was clear that there was a hollow ahead and yet the current was beginning to veer away from it.

The axon was beginning to break off into branches, into dendrites like those at the other end of the neuron, at the end where the nucleated cell body was. The axonian dendrites at the far end of the cell were fewer and thinner, but they were there. Undoubtedly, a portion of the cellular stream flowed into it, but the ship was in the main stream that curved away and they could take no chances.

They would have to push into the first dendrite encountered - if it could be done.

"There, Arkady, there," cried Konev, pointing, and it was only then that all the rest realized they were reaching the end of the axon. "Use your motors, Arkady, and push over."

Morrison could make out the soft throbbing of the motors as they edged the ship toward the side of the stream. The dendrite toward which they aimed was a tube that was slipping sideways, a huge tube at their size scale, so huge they could only see a small arc of its circumference.

They continued to edge closer to it and Morrison found himself leaning toward the dendrite, as though adding body English could improve matters.

But it was not a matter of reaching the tube itself, merely moving over an eddying section of fluid, a rushing of water molecules that quieted into gentle circles and then slipped beyond into another stream that was curving off in another direction.

The ship made the transition and was suddenly plunging forward into the tube opening.

"Turn off the motors," said Konev excitedly.

"Not yet," grumbled Dezhnev. "We may be too near the countercurrent emerging from this thing. Let me slip over a bit closer to the wall."

He did so, but that did not take long. They were now essentially moving with the current, not against it. And when Dezhnev did finally shut off the engine and pushed back his damp, graying hair, he heaved a great breath and said, "Everything we do consumes a ton of energy. There's a limit, Yuri, there's a limit."

"We'll worry about that later," said Konev impatiently.

"Will we?" said Dezhnev. "My father always said: 'Later is usually too late.' - Natalya, don't leave all this to Yuri. I don't trust his attitude toward our energy supply."

"Calm yourself, Arkady. I will take care to override Yuri if it becomes necessary. - Yuri, the dendrite is not very long, is it?"

"We will come to the ending in short order, Natalya."

"In that case, Sophia, please see to it that we are ready to adopt the acetylcholine pattern at a moment's notice."

"You'll give me the signal, then?" said Kaliinin.

"I will not have to, Sophia. I'm sure that Yuri will whoop like a Cossack when the end is in sight. Shift the pattern to acetylcholine at that moment."

They continued sliding along the final tubular remnant of the neuron they had entered a considerable time before. It seemed to Morrison that, as the dendrite continued to narrow, he could see the wall arc above him, but that was illusion. Common sense told him that even at its narrowest, the tube would appear to be a few kilometers across at their present molecular size.

And, as Boranova had foreseen, Konev lifted his voice in a great cry, probably quite unaware that he was doing so. "The end is ahead. Quick. Acetylcholine before we're swept around and back."

Kaliinin's fingers flickered over the keyboard. There was no indication from inside the ship that anything about it had changed, but somewhere up ahead was an acetylcholine receptor - or, more likely, hundreds of them - and the patterns meshed, positive to negative and negative to positive, so that the attraction between ship and receptor was sharp and great.

They were pulled out of the stream and melted into and through the wall of the dendrite. For a few minutes they continued to be pulled through the intercellular medium between the dendrite of the neuron they had just left and the dendrite of the neighbor neuron.

Morrison saw almost nothing. The ship, he felt, was sliding along - or through - a complex protein molecule and then he noticed the formation of a concavity, as when the ship had first entered the first neuron.

Konev had unclasped himself so that he could stand up. (Quite obviously, he was too excited to feel this was something he could do sitting down.)

He said, almost stuttering, "Now, according to the Nastiaspenskaya hypothesis, the filtering out of the important thoughts is most evident immediately after the synapse. Once the cell body is approached, the difference fades. So once we are in the neighboring dendrite, open your minds. Be ready for anything. Say whatever you hear out loud. Describe any images. I'll record everything. You, too, Arkady. Albert, you, too. - We're in now. Begin!"