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 were 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.
Boranova said, "Is there any way, Sophia, that you can give the ship an electric charge pattern that will slip us into the vein?"