Fantastic Voyage II: Destination Brain fv-2

by Isaac Asimov

  "Of course not," said Konev, "since you worked with animals who don't use words."

  "True," said Morrison. "Just the same, I once managed to run some tests on a human being, though I never reported it. I sensed no words then or images either."

  Konev shrugged it off.

  Morrison said, "You know, under the circumstances, it might be natural for Shapirov's mind to be full of family - if we accept your interpretation of what you thought you sensed. What would the chances be that he would be thinking of some esoteric extension of miniaturization mathematics?"

  "He was a physicist. Even his family came second to that. If we can sense words out of those skeptic waves, they'll be words dealing with physics."

  "You think that, do you?"

  "I am positive."

  The two fell quiet and for a few minutes there was no sound in the ship. Then Boranova said, "I've deminiaturized the ship to protein size and I have brought the process to a halt."

  A moment passed and then Dezhnev, with an unaccustomed tightness to his throaty voice, said, "Are things all right, Natasha?"

  Boranova said, "The mere fact that you can ask the question, Arkady, is an answer in the positive. Deminiaturization has stopped without incident."

  She smiled, but there was a definite trace of perspiration glistening at her hairline.

  57.

  The surface of the glial cell still stretched out as far as the eye could see into the dimness beyond the reach of the ship's light, but it had changed in character. The domes and ridges had faded out into a fine texture. The ropes that had extended from between the domes had become threads nearly impossible to see as the ship sped along the surface.

  Morrison's attention was, for the most part, on his computer, as he watched to see that the skeptic waves did not decline in intensity, but, periodically, he could not help but drift away from that and gaze at the panorama outside.

  Occasionally, there would emerge from the surface of the cell the typical dendritic processes of a nerve cell - even one that was merely a subsidiary glial cell. They branched and sub-branched like a tree in winter, growing out of the cell membrane.

  Even at the new and larger size of the ship, the dendrites were large when they emerged from the cell. They were like tree trunks, which, however, narrowed rapidly and were clearly flexible. Lacking the rigidity of the cartilage fibers, they swayed in the eddies set up by the ship's progress through the extracellular fluid. They swayed, indeed, at the ship's approach and Dezhnev rarely had to do anything to avoid them. They would bend out of line and the ship would pass them safely.

  Collagen fibers were fewer in the immediate neighborhood of the cell and, thanks to the larger size of the ship, were much thinner and more fragile. On one occasion, Dezhnev either did not see one looming directly ahead of the ship or did not care that it was. The ship brushed past it in a way that brought it just outside Morrison's seat. He flinched at the grating collision, but the ship was in no way damaged. It was the collagen fiber that bent, then snapped and dangled free. Morrison's head turned and his eyes followed the broken fiber for the second or so that it remained in view before floating away.

  Boranova must have seen it, too, and watched Morrison's reaction, for she said, "There's no reason for concern. There are trillions of those fibers scattered through the brain, so that one more or less doesn't matter. Besides, they heal - even in a brain as badly damaged as poor Shapirov's."

  "I suppose so," said Morrison, "yet I can't help but think we are crashing without any right through an infinitely delicate mechanism not meant for technological invasion."

  "I appreciate your feeling," said Boranova, "but hardly anything in the world seems to have been brought into being by geological and biological processes with any apparent pre-vision of human interference. Humanity does a great deal of wrong to Earth and to life, some of it wittingly. - Incidentally, I'm thirsty. Are you?"

  "Definitely," said Morrison.

  "You'll find a cup in the little recess under your right armrest. Pass it back."

  She distributed water to all five, saying matter-of-factly, "There's no shortage of water, so if you want seconds, say so."

  Dezhnev looked at his cup distastefully, while keeping one hand on the controls. He sniffed at it and said, "My father used to say: 'There is no drink like pure water, provided one realizes that it is alcohol that is the purifying agent.'"

  "Yes, Arkady," said Boranova. "I am quite sure your father purified his water frequently, but here on the ship, with your hands on the controls, you will have your water unpurified."

  "We must all go through privations now and then," said Dezhnev, who then downed his water and made a face.

  It might have been the taste of the water that caused Kaliinin to fumble between her legs. It took a moment for Morrison to realize that it was her turn to urinate and he turned his head toward the window and waited to see if another collagen fiber might go flying.

  Boranova said, "I suppose, strictly speaking, it's lunchtime, but we can do without. Still -"

  "Still what?" asked Dezhnev. "A good plate of piping hot borscht with sour cream?"

  Boranova said, "What I have smuggled in against regulations are bits of chocolate - high-calorie, zero-fiber."

  Kaliinin, who had disposed of her small damp paper towel and was shaking her hands to dry them, said, "It will rot our teeth."

  "Not immediately," said Boranova, "and you can rinse your mouth with a little water to reduce the sugar residue. Who wants one?"

  Four hands went up, Kaliinin's not the last. Morrison welcomed his gladly. He was fond of chocolate in any case and sucked at it to make it last longer. The taste reminded him poignantly of his boyhood in the outskirts of Muncie.

  The chocolate was gone when Konev said to Morrison in a low voice, "Have you sensed anything while we've been skimming past the glial cell?"

  "No," said Morrison. (He hadn't.) "Have you?"

  "I thought I did. The phrase 'green fields' crossed my mind."

  Morrison could not prevent himself from saying "Hmm" and for a while remained lost in thought.

  "Well?" said Konev.

  Morrison shrugged. "Phrases go through one's mind all the time. You hear something out of the corner of your ear, so to speak, and sometime later it penetrates your consciousness; or some stream-of-consciousness thoughts invade your mind and one phrase surfaces; or you can have an auditory hallucination of some sort."

  "It crossed my mind when I was looking at your instrument and concentrating."

  "You wanted to be aware of something, I suppose, and something promptly obliged by flitting through your mind in response. You get the same effect in dreams."

  "No. This was real."

  "How can you tell, Yuri? - I didn't sense any such thing. Did anyone else sense it, do you suppose?"

  "They wouldn't. No one else was concentrating on your machine. Perhaps no one else in the ship had a brain sufficiently like yours to sense on your wavelength, so to speak."

  "You're just guessing. Besides, what does the phrase mean?"

  "Green fields? Shapirov had a house out in the country. He would remember the green fields."

  "He might have merely supplied the image. You would supply the words."

  Konev frowned, paused a moment, then said in a clearly hostile manner, "Why are you so opposed to the possibility of getting a message?"

  Morrison allowed himself to be equally hostile. "Because I've been burned by reporting such sense perceptions. I've been ridiculed long enough and I have become cautious. An image of a woman and two children doesn't tell us anything. Neither does a phrase like 'green fields.' If you report it, how can you possibly tell it from a self-generated image or phrase? Now listen, Yuri, a hint, to be useful, must, however vaguely and indirectly, tie in with the quantum-relativity relationship. That we can report. Anything less than that is not compelling; it won't force belief. It will only succeed in hurting us. I speak from experience."

  Konev s
aid, "What, then, if you succeed in hearing something vital, something that bears on our project? Will you perhaps keep it to yourself?"

  "Why should I? If I sense something in physics relating to miniaturization, I would lack the background to understand it and keeping it to myself would get me nowhere. If some useful result is shared between us, this computer remains my machine and it is activated by my theory. I am the one who will get the major share of the credit. I won't keep it to myself, Yuri. Both my self-interest and my honor as a scientist will keep me from doing that. - And what about you?"

  "Of course I'll share whatever I sense. I have been doing so just now."

  "I don't mean 'green fields.' That is nonsense. Suppose you sense something very significant and I don't. Might it not occur to you that the knowledge would be a state secret, as miniaturization itself is? Would you then tell me that knowledge and risk the wrath of your Central Coordinating Committee."

  They had been speaking in whispers, heads together, but Boranova's ears picked up the key word. "Politics, gentlemen?" she asked frostily.

  Konev said, "We're discussing the possible uses of Albert's instrument, Natalya. If I learn something of importance from Shapirov's skeptic waves and Albert does not, he thinks I will keep it from him under the excuse that it is a state secret."

  Boranova said, "It well may be."

  Konev said mildly, "We need Albert's cooperation. It is his machine and his program and I am sure he knows how to work it at less than perfect efficiency. If he is not completely assured of our honesty and goodwill, he may arrange to have us sense nothing. I am willing to share anything that I sense if he will do the same."

  "The Committee may disapprove, as Albert himself pointed out," said Boranova.

  "Let it. I don't concern myself with it," said Konev.

  "I'll prove I love you, Yuri," interposed Dezhnev with a chuckle. "I won't quote you."

  Kaliinin said, "Natalya, I agree that we should be honest with Albert, since we must ask him to be honest with us. Using his own device with which he has experience, he is far more likely to come up with something useful than we are. A policy of quid pro quo is likely to be far more to our advantage than to his. - Isn't that so, Albert?"

  Morrison nodded. "I've been thinking precisely that and would have mentioned it if it looked as though you were going to tell me that it was against government policy to be honest with me."

  Boranova said, "Well, let us await events." The tension died down.

  Morrison remained busy with his own thoughts, watching his machine only in abstraction.

  And then Dezhnev said, "There's another cell just ahead - a kilometer or two. It looks as though it might be larger than the one we've been passing. Is that a neuron, Yuri?"

  Konev, who seemed to have been in a brown study of his own, snapped to attention. "Albert, what does your machine say? Is that a neuron?"

  Morrison was already handling his device. "It must be," he said. "I've never seen the skeptic waves this sharp."

  "Good!" said Dezhnev. "Now what?"

  58.

  Kaliinin looked thoughtfully at the cell surface below. She said, "Natalya, we'll have to miniaturize to glucose size again. Arkady, get us in among the dendrites so that we can get down to the surface of the cell body."

  Morrison watched the surface also. The dendrites were much more elaborate than those on the glia. The nearest one branched and branched again until it looked like a fuzzy frond vanishing beyond the reach of ship's light. Others, farther away, were fuzzier and smaller.

  Morrison suspected that the fuzziness was at least partly the result of Brownian motion. Surely there couldn't be much of that, however. Probably each final strand of the branchings - each twig - met a similar twig or some neighboring neuron to form that intimate near-touch called a synapse. The wavering of the twig would not be strong enough to break the contact or the brain couldn't do its work.

  Dezhnev had the ship approach the surface of the cell body, slowly slithering past the nearest dendrite (he was learning to handle the unbalance of the individual engines with a certain finesse, Morrison thought) - and, as he did so, it seemed to Morrison that the surface of the neuron was changing character.

  Of course, it had to, for the ship was miniaturizing again. The ridges in the cell surface were becoming more prominent and were dividing into domes. Between the phospholipid domes the hairs were becoming ropier. Receptors, thought Morrison. Each one of them was designed to link on to a particular molecule that would be useful to the neuron and certainly glucose would he the most useful of those.

  The downward change was considerably more rapid than the upward change. Absorbing energy was simple, while the energy release of deminiaturization was dangerous. Morrison understood that well by now.

  Kaliinin said, frowning in concern, "I don't know which receptors are for glucose, but a great many of them must be. Skim across them slowly, Arkady - very slowly. If we're caught, I don't want to tear loose - or to tear them loose, either."

  "No problem, little Sophie," said Dezhnev. "If I shut off the motors, the ship stops at once. It can't push through the giant atoms that surround us at all easily. Too viscous. So I just give it a touch of energy, enough to shoulder our way past the molecules of water, and we'll tiptoe across the receptors."

  "'Through the tulips,'" said Morrison, looking at Konev.

  "What?" said Konev, looking both annoyed and puzzled.

  "It's a phrase that went through my head. There's an old show tune called 'Tip Toe Through the Tulips With Me,' In English, the words are -"

  "What nonsense are you speaking?" snapped Konev.

  "I'm trying to point out that whenever someone says 'tiptoe' to me, I automatically hear the phrase 'through the tulips' in my mind. If I happen to be concentrating on my computer when someone says 'tiptoe,' I will still hear the phrase in my mind and it will not mean that I am getting it from the skeptic waves on the computer. Do you take my meaning?"

  "You're talking emptily," said Konev. "Leave me alone."

  But he looked shaken, Morrison thought. He had taken the meaning.

  They were now moving parallel to the surface of the neuron. The receptors were moving gently and Morrison realized that he couldn't tell which were empty and which had attached themselves to some of the molecules moving through the extracellular fluid with them.

  He tried to concentrate on those molecules. There seemed to be glitterings in the fluid which might have been the light of the ship's beacon reflected from molecules, but none of it showed up well. Even the surface of the cell membrane wasn't actually clear if you looked at it directly. It was more the surrealistic impression of a surface than an actual one - too few photons were being reflected and too few were reaching them on their small scale.

  Still, by the glitter, he could make out a kind of grittiness in the fluid they were passing through (water molecules, surely) and among them, now and then, something wormy-twisting, turning, closing up, then opening again. The immediate neighborhood of the ship was, of course, within the miniaturization field, so that atoms and molecules of the standard-size world were constantly shrinking as they entered - and expanding again as they left. The number of atoms doing so must be enormous but the energy change that resulted, even totaled over that number, were small enough so that it did not drain the ship perceptibly, or bring about spontaneous deminiaturization, or do any damage. - Or, at least, it seemed to do no damage.

  Morrison tried not to think about it.

  Boranova said, "I don't mean to question your ability, Sophia, but please check and make sure the ship has the electrical pattern of glucose."

  "I assure you it does," said Kaliinin.

  And as though to give notice that that was indeed so, the ship seemed to twist in mid-fluid, judging by the sudden shift in view through the walls.

  Under ordinary conditions, such a twist would have thrown every person on the ship hard against the wall or the seat arm. Mass and inertia, however, were at vi
rtually zero and there was only a faint swaying, hardly distinguishable from that which they associated with Brownian motion.

  Kaliinin said, "We've attached ourselves to a glucose receptor."

  "Good," said Dezhnev. "I've turned off the motor. Now what do we do?"

  "Nothing," said Kaliinin. "We let the cell do its work and we wait."

  The receptor did not actually make contact with the ship. This was good, for had it come any closer it would have entered the miniaturization field and its tip would have collapsed. As it was, there was a close meeting of electrical fields only, negative to positive and positive to negative. The attractions were not the full attractions but the lesser ones that resembled hydrogen bonds. It was enough to hold, but weak enough to allow the ship to pull away somewhat, as though it were connected to the receptor by rubber bands rather than by grappling hooks.

  The receptor stretched the length of the ship and was irregular in outline, as though it were embracing a pattern of bulges along the plastic hull. The hull was smooth and featureless to the eye, of course, but Morrison was quite certain that there was an electric field that bulged in just the locations where the hydroxyl groups would be in the glucopyranose structure, the bulges taking on just the shapes they would in the natural molecule.

  Morrison looked out again. The receptor virtually blanked out vision on the side of the ship along which it lay. If he looked beyond the receptor, however, he could see a farther stretch of the neuron's surface, seemingly without end, for it vanished beyond the reach of the ship's light.

  The neuronic surface seemed to be heaving slightly and he could see greater detail. Among the regular domes of the rank and file of phospholipid molecules, he caught occasional glimpses of an irregular mass, which he guessed to be a protein molecule that ran through the thickness of the cell membrane. It was to these molecules that the receptors were attached, which did not surprise Morrison. He knew that the receptors must be peptides - chains of amino acids. They were part of the thread of a protein backbone, sticking outward, each different receptor made up of different amino acids in a specific order so designed as to possess an electric field pattern matching (in opposing attractions and physical shape) that of the molecule it was designed to pick up.