Fantastic Voyage II: Destination Brain fv-2

by Isaac Asimov

  "That's true," said Kaliinin. "An automated pattern maker would place us in the red corpuscle pattern as a way of following the path of least resistance, and it would do little more than that. After all, it would be a useless expense and perhaps an impractical exercise altogether to try to instil in an automated pattern maker the ability to change appropriately in response to all sorts of improbable conditions. When I am present, however, I have the capacity to do almost anything. I can change the pattern to meet an unlikely emergency, to test the value of something earlier unthought of, or simply to suit a whim. - For instance, I could change the ship's pattern to that of an E coli bacterium and the white cell would attack at once."

  "I'm sure of that," said Morrison, "but don't do it, please."

  "No fear," said Kaliinin. "I won't."

  But Boranova's voice sounded in sudden - and uncharacteristic - excitement. "On the contrary, Sophia, do that!"

  "But, Natalya -"

  "I mean it, Sophia. Do it. We haven't tested your instrument under field conditions, you know. Let's try it."

  Konev muttered, "That's a waste of time, Natalya. Let us first get to where we're going."

  Boranova said, "It won't do us any good to get there - if we can't enter a cell. Here is an immediate opportunity at hand to see if Sophia can control the behavior of a cell."

  "I agree," said Dezhnev boisterously. "This has been a remarkably uneventful trip so far."

  "That's the best kind, I should think," said Morrison.

  But Dezhnev held up a disapproving hand. "My old father used to say: 'To want peace and quiet above all else is to hope for death.'"

  "Go ahead, Sophia," Boranova said firmly. "We waste time."

  Kaliinin hesitated a bare moment - the time required, perhaps, to remember that Boranova was captain of the ship - then her hand flickered over the controls of her device and the configurations upon the television screen altered markedly. (Morrison admired, in an apprehensive sort of way, the speed with which she did it.)

  Morrison lifted his eyes to the white cell ahead, and for a moment he saw no change. And then it seemed as though a fit of trembling overtook the monster and Dezhnev whispered, "Aha, it recognizes the presence of its prey."

  At the extreme forward end of the white cell, its substance seemed to bulge toward and all around them in an uneven circle. At the same time, the substance in the center retreated as though it were being sucked in. Morrison envisioned a monster's jaws preparing for a meal.

  Konev said, "It works, Natalya. That creature ahead is preparing to envelop and engulf us."

  Boranova said, "So it is. Very well, Sophia, restore us to the red cell mode."

  Again Kaliinin's fingers flickered and the configurations on the screen returned (as nearly as Morrison's memory could judge) to what they had earlier been.

  This time, however, the white cell remained unaffected. Its outer rim was shooting past the ship, which was now heading into the deep central concavity.

  41.

  Morrison was appalled. The entire ship was encased by something that looked precisely like fog - a gritty granular fog, within which a multilobed object, faintly denser than the rest, writhed its way around them. Morrison knew that this must be the nucleus of the white cell.

  Konev snapped out angrily, "Apparently, once the white cell gears itself for engulfment, the rest is automatic and nothing will stop it. - What now, Natalya?"

  Boranova replied quietly, "I admit I hadn't expected this. The fault is mine."

  "What's the difference?" said Dezhnev, frowning. "It's no matter. What can this blob do to us? It cannot crush us. It is not a boa constrictor."

  Konev said, "It can try to digest us. We're in a food vacuole right now and digestive enzymes are pouring in around us."

  "Let them pour," said Dezhnev. "I wish them the joy of the attempt. The ship's wall is not digestible to anything a white cell has. After a while, it will reject us as indigestible residue."

  "How will it know?" asked Kaliinin.

  "How will it know what?" snapped Dezhnev.

  "How will it know we are indigestible residue? It was spurred into activity by our bacterial charge pattern."

  "Which you removed."

  "Yes, but as someone remarked, the white cell, once stimulated, apparently has to go through its whole cycle of activity. It is not a thinking device; it is entirely automatic." Kaliinin was frowning now and looking around at the others. "It seems to me that the white cell will continue trying to digest us until it is given the appropriate stimulus that will put its engulfment mechanism into reverse and allow it to eject us."

  Boranova said, "But we now have the charge pattern of a red corpuscle again. Don't you think that would stimulate rejection? It doesn't eat red cells."

  "I think it's too late for that," said Kaliinin a little diffidently, as though nervous about standing up to Boranova. "The red corpuscle pattern keeps it unengulfed, but once it is engulfed by some means, it would seem that the pattern alone is insufficient to spark ejection. After all, here we are; we are not being ejected."

  Her eyes - all five pairs of eyes, in fact - uneasily surveyed the wall of the ship. They were trapped in the cloudy cell.

  "I think," Kaliinin went on, "that there's a charge pattern to the kind of indigestible residue left by the bacteria the white cell is designed to engulf and that that alone would be a trigger for ejection."

  "In that case," said Dezhnev, "give it the pattern it wants, Sophia, my little chicken."

  "Gladly," said Kaliinin, "if you will tell me what it is because I don't know. I can't just try patterns at random. The number of possible patterns is astronomical."

  "As a matter of fact," said Konev, "can we be sure the white cell ejects anything at all? Perhaps indigestible residue becomes part of its granular material and remains within it until it is removed and dismantled in the spleen."

  Boranova said sharply (perhaps weighed down with the knowledge that she was responsible for their present situation, thought Morrison), "There is no point in babbling. Is there a constructive suggestion?"

  Dezhnev said, "I can turn on the microfusion motors and bore a way out of the white cell."

  "No," said Boranova sharply. "Do you know the direction which we are heading at this moment? Inside this food vacuole we may be slowly turning or the vacuole itself may be drifting through the cell's substance. If you smash your way outward, you may damage the wall of the blood vessel and the brain itself."

  Konev said, "For that matter, white cells can wiggle out of a capillary, working their way between the cells that make up the capillary wall. Since the path we have taken has led us into an arteriole branch that has narrowed to just about capillary size, we can't even be sure that we're still in the bloodstream."

  "Yes, we can," said Morrison suddenly. "The white cell can pinch itself small, but it can't pinch us small. If it squeezes out of the vessel, it would be forced to leave us behind. - And that would be a good thing, except that it hasn't done it."

  "There you are," said Dezhnev. "I should have thought of it sooner. Natasha, make us bigger and crack the white cell open. Give it indigestion like it has never had."

  Again a sharp negative from Boranova. "And crack the blood vessel open, too? The blood vessel is fairly small now, not much wider than the white cell."

  Kaliinin said, "If Arkady will get in touch with the Grotto, someone there might have an idea."

  There was silence for a moment and then Boranova said in a half-strangled way, "Not just yet. We have done something foolish - well, I have - and you know as well as I do that it would be better for all of us if we didn't need help."

  "We can't wait forever," said Konev restlessly. "The fact is that I don't know where we are by now. I can't rely on the white cell drifting with the bloodstream or with maintaining any given speed, for that matter. Once we are lost, it may take considerable time to locate ourselves and we may need help from the Grotto to do it, too. In that case, how do we explain bein
g lost?"

  Morrison said, "How about the air-conditioning?"

  There was a pause and Boranova said, "What do you mean, Albert?"

  "Well, we're sending miniaturized subatomic particles out of the ship and into interplanetary space. They carry heat away from the ship, I was told, so that we remain cool even in the all-pervasive warmth of the body we're in. That coolness must be something the white cell is not designed to tolerate. If we turn up the air-conditioning and become colder still, there may come a time when the white cell will be uncomfortable enough to eject us."

  Boranova mulled this over and said evenly, "I think - possibly - that might work."

  Dezhnev said, "Don't bother thinking. I've turned up the air-conditioning to maximum. Let's see if anything happens besides all of us getting frostbite."

  Morrison watched the fog outside. He was well aware that he was as tense as the others. He was not in agony over an unfortunate decision - an ill-advised experiment. Nor was he biting his nails over the fate of Shapirov and yet - Tapping his own emotions, it occurred to him that having come thus far, having been miniaturized and finding himself in a small cerebral arteriole, he suddenly had an urge to check out his theories. Had he come this far in order to turn back and spend the rest of his life, holding up an imaginary thumb and forefinger nearly in contact and saying in the depth of his mind, "Missed it by that much"?

  Very well, then. He had passed from desperately not wanting to attempt the project to a definite reluctance to abort it.

  Dezhnev's voice broke in on his thoughts. "I don't think this little animal likes what's happening."

  Morrison was conscious of a biting chill, and shivered as he became aware that the thin cotton uniform he wore was a totally inadequate shield against this sudden onset of winter.

  And perhaps the white cell "thought" this, too, for the fog thinned and a rift appeared in it. Then, in another moment or two, the surroundings were clear and the white cell was a ball of fog to their rear, drifting away - or perhaps crawling away - amoebalike, from an unpleasant experience.

  Boranova said (sounding a little dumbfounded), "Well, it's gone."

  Dezhnev waved both hands high in the air. "A toast - if we had a small swallow of vodka with us - to our American hero. It was an excellent suggestion."

  Kaliinin nodded at Morrison and smiled. "It was a good idea."

  "As good as mine was bad," said Boranova, "but at least we know that your technique can do what it should, Sophia - as long as we know enough. And as for you, Arkady, ease the air-conditioning intensity before we all catch pneumonia. - So you see, Albert, we have already done well to take you with us."

  "Perhaps," said Konev tightly, "but in the meanwhile, I think the white cell took us on an excursion. We are not where we were and I do not know exactly where we are."

  42.

  Boranova's lips tightened and she asked with some difficulty, "How can you not know where we are? We were inside the white cell only a few minutes. It couldn't have moved us into the liver, could it?"

  Konev seemed at least equally upset. "No, we're not in the liver, Madame." (He came down heavily on the honorific, giving it the French pronunciation.) "But I suspect the white cell, dragging us with it, has turned into a branching capillary so that we are now out of the mainstream of the arteriole - which was not yet quite a capillary - that we were carefully following."

  "Which capillary did it turn into?" asked Boranova.

  "That is what I don't know. There are a dozen capillaries it might have turned into and I don't know which one it was."

  "Doesn't your red marker -" began Morrison.

  "My red marker," said Konev at once, "works by dead reckoning. If I know where we are and the speed at which we're progressing, it will move along with us, turning when I tell it to turn."

  "You mean," said Morrison incredulously, "it only marks your position insofar as you know your position - no more than that?"

  "It is not a magical marker, no," said Konev freezingly. "It acts to mark our place and keep track of it, lest we lose it in the confusion of the three-dimensional complexity of the bloodstream and the neuronic networks, but we have to guide it. At this stage, it's not complex enough to guide itself. In an emergency, we can be located from outside, but that's a time-consuming process."

  It seemed to be time for someone to ask a classically foolish question and that someone turned out to be Dezhnev. He said, "Why should the white cell have turned off into a capillary?"

  Konev turned red. Speaking so rapidly that Morrison could hardly make out the Russian, he said, "And how should I know that? Am I privy to the thought processes of a white cell?"

  "That's enough," said Morrison sharply. "We're not here to fight with each other." (He noted the quick look that Boranova had shot toward him and he chose to interpret it as representing gratitude.)

  "Actually," he went on, "the solution is simple. We're in a capillary. Very well. The current is at a creeping pace in capillaries, so where is the difficulty in making use of the famous microfusion engines? If you put them into reverse, we will just back out of this capillary and eventually - not a very long eventually, either - we will be back at the junction point and in the arteriole again. Then we continue onward until we get to the proper turnoff and into the proper capillary. We'll have lost a little time and spent a little power, that's all."

  Morrison's statement was greeted with solemn stares. Even Konev, who generally spoke - when he did - with his face steadfastly forward, turned now, his angry frown concentrated on Morrison.

  Morrison said uneasily, "Why are you all looking at me like that? It's a perfectly natural course of procedure. If you had been driving a car and accidentally turned into a narrow alley and found it the wrong one, wouldn't you back out?"

  Boranova was shaking her head. "Albert, I'm sorry. We have no reverse."

  "What?" Morrison stared at her blankly.

  "We have no reverse. We have only a forward drive. Nothing more."

  Morrison said, "How is it possible to - No reverse gear at all?"

  "None."

  Morrison looked around at the other four faces and then burst out, "Of all the stupid, incompetent, maddening situations. It's only in the Sov-"

  He stopped.

  Boranova said, "Finish the thought. You were going to say that it's only in the Soviet Union that such a situation would be allowed to arise."

  Morrison swallowed, then said grumpily, "I was going to say that, yes. It might be an ill-tempered statement, but I'm angry - and the statement may be true, at that."

  "And do you think we're not angry, Albert?" said Boranova with her glance level upon him. "Do you know how long we've been working on a ship like this? Years! Many years! Since miniaturization first seemed to become a practical possibility, we have been thinking of entering a bloodstream someday and exploring the working mammalian body - if not the human body - from within.

  "But the more we planned and the more we designed, the more expensive the project grew, and the more stubborn the budgeteers in Moscow became in response. I can't blame them; they had to balance the expense of this project against other expenses in areas that were far less problematical than miniaturization was. So, as a result, the ship grew simpler and simpler in concept, as we cut out first this, then that, then the other thing. Do you remember when you Americans were building your first shuttles? What you planned and what you got?

  "In any case, we ended up with an unpowered craft, fit for observation only. We planned to enter the bloodstream and let the current carry us where it would. When we had all the information we could get, we would slowly deminiaturize. This would kill the animal which we had been studying - it would only be an animal, of course, but even so some of us agonized over that. That was all this ship was planned for. Nothing more. We had no way of knowing that we would suddenly be faced with a situation in which we had to invade a human body, in which we had to get to a specific spot in the brain, in which we would have to emerge wi
thout killing the body. In which we had to - and all we had was this ship, which was not meant for the job at all."

  The anger and contempt on Morrison's face had vanished into a frown of concern. "What did you do?"

  "We worked as fast as we could. We improved the microfusion motors and a few other things, frightened that at any moment Shapirov would die, and equally frightened - or more so - that our hurry would cause us to make some fatal mistake. Well, I don't think we made any fatal mistakes, but still the microfusion motors we ended up with were to be used for acceleration only when absolutely necessary - they had originally been designed only for lighting, air-conditioning, and other low-energy uses. Of course, we lacked the time to do a complete job, so - no reverse gear."

  "Didn't anyone point out that there might just be a chance you would want to go into reverse?"

  "That would mean more money and there was none to be had. After all, we had to compete with space, which was a going concern, with the realistic needs of agriculture, commerce, industry, crime control, and half a hundred other departments of government all clutching at the national purse. Of course we never had enough."

  Dezhnev sighed and said, "And so here we are. As my good father used to say: 'Only simpletons go to fortune-tellers. Who else would be in such a hurry to hear bad news?'"

  "Your father is telling me nothing I don't know, Arkady. At least with that remark. I'm afraid to ask, but can we simply turn the ship?" Morrison asked.

  Dezhnev said, "You are wise to be afraid. In the first place, the capillary is too narrow. The ship has no room to turn."

  Morrison shook his head impatiently. "You don't have to do it in the ship's present size. Shrink it a bit. Miniaturize it. You're going to have to miniaturize anyway before getting inside a cell. Do it now and turn it."

  Dezhnev said mildly, "And in the second place, we can't turn it any more than we can go backward. We have a forward gear and that is all."

  "Unbelievable," whispered Morrison to himself. Then aloud, "How could you consent to begin this project with so inadequate a ship?"