by Isaac Asimov
Here he was, then, buried in a planetary object of dead organic matter. He felt impatience over the pause for mourning. Time for that later, but meanwhile - He said in a voice that was perhaps a little louder than it ought to have been, "How do we get out?"
Boranova looked at him in surprise, eyes widening. (Morrison was certain that in her grief for Shapirov the thought of leaving had been momentarily buried.)
She cleared her throat and made a visible effort to be her usual businesslike self. She said, "We must deminiaturize to some extent, to begin with."
Morrison said, "Why only to begin with? Why not deminiaturize all the way to normality right now?" Then, as though to forestall the inevitable objection, "We will inflict damage on Shapirov's body, but it is a dead body and we are still alive. Our needs come first."
Kaliinin looked at Morrison reproachfully. "Even a dead body deserves respect, Albert, especially the dead body of a great scientist like Academician Pyotr Shapirov."
"Yes, but surely not to the entent of risking five lives." Morrison's impatience was growing. Shapirov was only someone he had known by distant reputation and peripherally - to Morrison he was not the demigod he seemed to be to the others.
Dezhnev said, "Aside from the question of respect, we are enclosed by Shapirov's cranium. If we expand to fill that cranium and then try to crumble the cranium by the effect of our miniaturization field, we will lose too much energy and deminiaturize explosively. We must first find our way out of the cranium."
Boranova said, "Albert is right. Let's begin. I will deminiaturize to cell size. Arkady, have the people in the Grotto determine our exact position. Yuri, make sure you locate that position accurately on your cerebrograph."
Morrison stared out the hull at the distant cell membrane - a brighter and more continuous sparkle, one that was visible through the occasional flicker of light from the intervening molecules.
The first indication of deminiaturization was the fact that the molecules - subsided. (It was the only word Morrison could think of to describe what happened.)
It was as though the little curved swellings that filled the space around them - and which Morrison's brain constructed out of twinklings rather than saw directly - shrank. It was for all the world as though they were balloons with the air being let out of them until the surroundings seemed relatively smooth.
But even as the liquid around them grew smooth, the large macromolecules in the distance - the proteins, the nucleic acids, the still larger cellular structures - also shrank and, in doing so, grew more distinct. The sparks of light they reflected were more closely spaced.
The cell membrane itself seemed to be approaching and it, too, could be seen more clearly. It came closer still and yet closer. The ship was, after all, in a narrow dendrite that projected from the cell body itself and if the ship was going to enlarge to the size of a cell, it would have to grow much larger than this mere projection.
It was clear that the membrane was going to collide with the ship and Morrison automatically clenched his teeth and steeled himself for the shock of impact.
There was none. The membrane came closer and closer and then simply separated and was not there. It was too thin a structure and too lightly bound to withstand the consequences of being forced into a miniaturization field. Though the ship was derniniaturizing to an extent, it was still far, far smaller than the normal world around it and the molecules of the membrane, on entering the field and shrinking, lost contact with each other so that the integrity of the whole vanished.
Morrison watched everything after that with fascination. The surroundings seemed chaotic until, as objects continued to shrink, he began to recognize the intercellular jungle of collagen that they had encountered before entering the neuron. That jungle continued to shrink, in its turn, until the collagen trunks and cables became nothing more than twine.
Boranova said, "And that is all. We will want to be able to fit within a small vein."
Dezhnev grunted. "That is all under any circumstances. Our remaining energy supply is not great."
Boranova said, "It will last until we find our way out of the cranium, surely."
Dezhnev said, "We can hope so. However, you're only the captain of the ship, Natasha; you are not the captain of the laws of thermodynamics."
Boranova shook her head as though in reproof and said, "Arkady, have them determine our position - and don't lecture me."
Konev said, "I'm certain, Natalya, that it is not terribly important to determine our position. It cannot be measurably different from what it was when we left the capillary. All our wanderings since have merely taken us to a nearby neuron and from that to a neighboring neuron. The difference in position on even an ordinary microscopic scale is scarcely measurable."
And then, after a wait of several minutes, the position came through and Konev said, "As I told you."
Morrison said, "What's the good of the position, Yuri? We don't know which way we're headed and we can only go in whatever direction that might be. Now that communications are restored, we can't steer."
Konev said, "Well, then, since there is only one way in which we can head, we will head in that direction. I'm sure that Arkady's father had a saying concerning that."
Dezhnev said at once, "He used to say: 'When only one course of action is possible, there is no difficulty in deciding what to do.'"
"You see?" said Konev. "And we will find that whatever direction we go in, we will find a way out. Move ahead, Arkady."
The ship moved forward, ploughing through the now fragile threads of collagen, splashing through a neuron, and cutting across a thin axon. (It was hard to believe they were recently inside one of those axons and that it had seemed like a highway a hundred kilometers across.)
Morrison said dryly, "Suppose that Shapirov was still alive when it became necessary for us to leave his body. What would we have done?"
"What do you mean?" said Boranova.
"I mean, what alternative is there to this? Would we not have had to determine our position? And to do that, would we not have had to establish communications? And once that was done, would we not have been able to move in only one direction - forward? Would we not have had to deminiaturize in order not to have to travel the equivalent of tens of thousands of kilometers, but merely the equivalent of a few kilometers? In short, in order to get out, would we not have had to push our way through the living neurons of a living Shapirov, as we are now pushing our way through dying and dead ones?"
Boranova said, "Well - yes."
"Where, then, is the respect for a living body? After all, we actually hesitated to violate the integrity of a dead one."
"You must understand, Albert, that this is an emergency operation with an inadequate ship. We have no choice. And, in any case, it is not like your suggestion that we deminiaturize completely in the brain, smashing the cranium and leaving Shapirov headless. Our present course, even if Shapirov was alive, would destroy a dozen neurons - or possibly a hundred - and that would not have been likely to make Shapirov's condition appreciably worse. Brain neurons are continually dying throughout life - like red corpuscles."
"Not quite," said Morrison grimly. "Red corpuscles are continually replaced. Neurons never are."
Konev interrupted, his voice rather loud, as though he were impatiently overriding the idle talk of others. "Arkady, stop. We need another position determination."
There was at once a dead silence within the ship, one that continued - as though any speech might interfere with the measurements being made in the Grotto or might hamper the concentration of those making the measurement.
Finally Dezhnev whispered the measurements to Konev, who said, "Confirm them, Arkady. Make sure you have them right."
Morrison unclasped himself. He was still virtually without mass, but there was distinctly more of it than there had been when they were maneuvering within the cell. He pulled himself cautiously upward, so that he could see the cerebrograph over Konev's shoulder.
There wer
e two red spots on it, with a thin red line connecting them. The map displayed on the screen condensed a bit, the two dots shrinking toward each other, and then it expanded again in a different orientation.
Konev's fingers worked busily over the computer keys and the map grew double and uninterpretable. Morrison knew, however, that Konev could view it through a device that would render it stereoscopic, displaying a third dimension.
Konev laid down that device and said, "Natalya, this time chance is on our side. Wherever we are and in whatever direction we were traveling, we'd be bound to encounter a small vein sooner or later. In this case, it is sooner. We are not far away and we will strike it in such a way that we will be able to enter."
Morrison heaved an internal sigh of relief, but could not help saying, "And what would you have done if chance had dictated a vein very far away?"
Konev said coolly, "Then I would have had Dezhnev break communications again and steer to a closer one."
Dezhnev, however, turned to stare at Morrison, made a grimace of disagreement, and mouthed the words, "Not enough energy."
"Move forward, Arkady," said Boranova peremptorily, "and get to the vein."
After a few minutes, Dezhnev said, "Yuri's map is right, which I wouldn't have bet on with any enthusiasm. That's it ahead."
Morrison found himself staring at a curving wall reaching into the indefinite haze upward and downward and with just a faint suggestion of tiling to it. If it was a vein, it was as yet not very far removed from a capillary. Morrison wondered uneasily if the ship would be able to fit inside it.
76.
Boranova said, "Is there any way, Sophia, that you can give the ship an electric charge pattern that will slip us into the vein?"
Kaliinin looked doubtful and Morrison, holding up his hand, said, "I don't think so, Natalya. The individual cells may not be entirely dead even now, but certainly the organization within them has been destroyed. I don't think any cell in the body can take us in by pinocytosis or by any other means.
"What do I do, then?" said Dezhnev unhappily, "Force my way in?"
"Of course," said Konev. "Lean against the vein wall. A small bit of it will then miniaturize and disintegrate and you can move in. You won't have to use your motors much."
"Ah," said Dezhnev, "the expert speaks. The vein will miniaturize and disintegrate at the expense of our field and that would take energy, too - more energy than forcing our way in would."
"Arkady," said Boranova, "don't be angry. This is not the time for it. Use your motors moderately and take advantage of the first weakening of the vein wall through miniaturization to burst through. Using both techniques will consume less energy than either separately."
"We can hope so," said Dezhnev, "but saying so doesn't make it so. When I was little, my father said to me once: 'Vehemence, my little son, is no guarantee of truth.' He told me this when I swore with great earnestness that I had not broken his pipe. He asked me if I understood the statement. I said I didn't and he explained it to me very carefully. Then he walloped me."
"Yes, Arkady," said Boranova, "but move in now."
Konev said, "It's not as though you're going to flood the brain with blood. It wouldn't matter now that Shapirov is dead, but, as it happens, the blood isn't flowing now. Virtually nothing will leak."
"Ah," said Dezhnev, "this raises an interesting point. Ordinarily, once we enter a vein, the blood flow would carry us in a particular direction. Without blood flow, I must use my engines - but in which direction must we go?"
"Once we penetrate at this point," said Konev calmly, "you will turn to the right. So my cerebrograph says."
"But if there is no current to turn me to the right and if I enter at an angle to the left?"
"Arkady, you will enter at an angle to the right. My cerebrograph tells me that, too. Just push in, will you?"
"Go ahead, Arkady," said Boranova. "We have no choice but to rely on Yuri's cerebrograph."
The ship moved forward and, as the prow touched the vein wall, Morrison could feel the slight vibration of the laboring motors. And then the wall simply gave and pulled away in all directions and the ship was inside.
Dezhnev stopped the motors at once. The ship moved in at a rapidly slowing pace, rebounded off the far wall (maintaining contact so briefly as to cause no damage that Morrison could see), and straightened out with the long axis of the ship along the enormous tunnel of the vein. The ship's width was better than half the width of the blood vessel.
"Well," said Dezhnev, "are we pointed in the right direction? If we're not, there's nothing to be done. I can't back up. We fit the vein too tightly for Albert to get out and turn us around and we have an insufficient remaining supply of energy to miniaturize further and make such a turn possible."
"You're pointed in the right direction," said Konev sternly. "Just get moving and you'll find out soon enough. The vessel will get larger as we move."
"Let's hope it does. - And if it does, how far do we have to travel before we can move out of the body?"
"I can't say yet," said Konev. "I have to follow the vein on my cerebrograph, consult with the people in the Grotto, and arrange for the insertion of a hypodermic needle into the vein as close as possible to the position in which we'll be when we emerge from within the cranium."
Dezhnev said, "May I explain that we cannot move on forever. What with miniaturizing and deminiaturizing, with steering at very low efficiency, with wrong capillaries, and with chasing after Albert when he was lost, we have used up much more energy than we had counted on using. We had much more energy than we thought we'd need, but, even so, we've almost used it all."
Boranova said, "Do you mean we're out of energy?"
"Just about. Haven't I been telling you this for quite a while?" said Dezhnev. "Haven't I been warning you we were running low?"
"But how low are we? Are you saying we don't have enough to carry us out of the cranium?"
"Ordinarily, we would have plenty for that, even now. If we were in a living vein, we could count on a blood current sweeping us along. But there is no current. Shapirov is dead and his heart isn't beating. That means I'll have to force my way through the bloodstream with my motors going and the cooler the stream gets, the more viscous it will become, the harder the motors will have to work, and the more rapidly the energy supply will run out."
Konev said, "We have only a few centimeters to go."
Dezhnev said furiously, "Only a few? Less than the width of my palm? Really? At our present size, we've got kilometers to go."
Morrison said, "Should we deminiaturize further, then?"
"We can't." Dezhnev was now speaking very loudly. "We don't have the energy for it. Uncontrolled deminiaturization takes no energy; it releases energy. But controlled deminiaturization - Look, Albert, if you jump out of a high window, you will reach the ground without effort. But if you want to survive the ordeal and if you want to be lowered slowly while you hang on to a rope, that takes a great deal of effort. Understand?"
Morrison muttered, "I understand."
Kaliinin's hand stole to his and squeezed it gently. She said in a low voice, "Don't mind Dezhnev. He grumbles and howls, but he'll get us there."
Boranova said, "Arkady, if vehemence doesn't guarantee truth, as you told us just now, neither does it guarantee a cool head and a solution. Rather, the reverse. So why don't you just push your way along the vein and perhaps the energy will last until we reach the hypodermic."
Dezhnev scowled and said, "It's what I will do, but if you want me to keep a cool head, you must let me get rid of some heat."
The ship began to move and Morrison thought to himself: Every meter we go is a meter closer to the hypodermic needle.
It didn't make much sense as a comforting thought, since to fail to reach the needle by a small distance might be as fatal as to fail by a large distance. Yet it worked to slow the beat of his heart and it gave him a sense of accomplishment as he watched the wall slide rapidly backward.
/> The red corpuscles and platelets seemed far more numerous now than they had been in the arteries and capillaries on the way in. Then there had been a blood flow and there had been only the relatively few objects in their immediate neighborhood that had moved along the flow with them. Now the various formed bodies were largely motionless and the ship moved past what seemed countless numbers, squeezing them right and left and leaving them behind, bobbing, in their wake.
They even passed an occasional white cell, large and globular and quiescent. Now, though, they were totally unresponsive to the presence of a foreign object speeding by. In one case, the ship simply whipped through a white cell and left it sprawling behind.
Konev said, "We are going in the right direction. The vein is now distinctly wider than it was."
And so it was. Morrison had noticed that without managing to grasp the significance. He had been too intent on simply moving.
He felt a small surge of hope. To have been going in the wrong direction would have been total disaster. The vein would have narrowed and burst, leaving them adrift in gray matter with, perhaps, insufficient fuel to find and reach another vein.
Konev was taking down something that Dezhnev was repeating to him. He nodded and said, "Have them confirm those figures, Arkady. - Good!"
He spent some time with his cerebrograph and then said, "Listen, they know the vein we're in and they will be inserting a hypodermic needle at a specific spot that I have marked off on the cerebrograph. We will reach it in half an hour or a little less. - Can you keep going for half an hour, Arkady?"
"More likely a little less. If the heart was beating -"
"Yes, I know, but it isn't," said Konev. Then he said, "Natalya, may I have whatever records you have concerning what we have sensed of Shapirov's thought processes? I am going to send the raw data - completeout to the Grotto."
Boranova said, "You mean in case we don't make it out."
"That's exactly what I mean. This material is what we went in for and there's no reason to have it perish with us if we can't get out."
"That's a proper attitude, Yuri," said Boranova.
