"No. We"re switching back to air. Now start breathing as fast as you can."
Hall turned back to Stone. "Give him a higher carbon dioxide atmosphere."
"But the organism flourishes in carbon dioxide!"
"I know, but not at an unfavorable pH of the blood. You see, that"s the problem: air doesn"t matter, but blood does. We have to establish an unfavorable acid balance for Burton"s blood."
Stone suddenly understood. "The child," he said. "It screamed.
"Yes."
"And the old fellow with the aspirin hyperventilated."
"Yes. And drank Sterno besides."
"And both of them shot their acid-base balance to h.e.l.l," Stone said.
"Yes," Hall said. "My trouble was, I was hung up on the acidosis. I didn"t understand how the baby could become acidotic. The answer, of course, was that it didn"t. It became basic-- too little acid. But that was all right-- you could go either way, too much acid or too little-- as long as you got out of the growth range of Andromeda."
He turned back to Burton. "All right now," he said. "Keep breathing rapidly. Don"t stop. Keep your lungs going and blow off your carbon dioxide. How do you feel?"
"Okay," Burton panted. "Scared...but...okay."
"Good."
"Listen," Stone said, "we can"t keep Burton that way forever. Sooner or later..."
"Yes," Hall said. "We"ll alkalinize his blood."
To Burton: "Look around the lab. Do you see anything we could use to raise your blood pH?
Burton looked. "No, not really."
"Bicarbonate of soda? As...o...b..c acid? Vinegar?"
Burton searched frantically among the bottles and reagents on the lab shelf, and finally shook his head. "Nothing here that will work."
Hall hardly heard him. He had been counting Burton"s respirations; they were up to thirty-five a minute, deep and full. That would hold him for a time, but sooner or later he would become exhausted-- breathing was hard work-- or pa.s.s out.
He looked around the lab from his vantage point. And it was while doing this that he noticed the rat. A black Norway, sitting calmly in its cage in a corner of the room, watching Burton.
He stopped.
"That rat..."
It was breathing slowly and easily. Stone saw the rat and said, "What the h.e.l.l..."
And then, as they watched, the lights began to flash again, and the computer console blinked on: EARLY DEGENERATIVE CHANGE IN GASKET V-1 12-6886.
"d.a.m.n," Stone said.
"Where does that gasket lead?"
"It"s one of the core gaskets; it connects all the labs. The main seal is--"
The computer came back on.
DEGENERATIVE CHANGE IN GASKETS.
A-009-5478.
V-430-0030.
N-966-6656.
They looked at the screen in astonishment. "Something is wrong," Stone said. "Very wrong."
In rapid succession the computer flashed the number of nine more gaskets that were breaking down.
"I don"t understand..."
And then Hall said, "The child. Of course!"
"The child?"
"And that d.a.m.ned airplane. It all fits."
"What are you talking about?" Stone said.
"The child was normal," Hall said. "It could cry, and disrupt it"s acid-base balance. Well and good. That would prevent the Andromeda Strain from getting into its bloodstream, and multiplying, and killing it."
"Yes, yes," Stone said. "You"ve told me all that."
"But what happens when the child stops crying?
Stone stared at him. He said nothing.
"I mean," Hall said, "that sooner or later, that kid had to stop crying. It couldn"t cry forever. Sooner or later, it would stop, and its acid-base balance would return to normal. Then it would be vulnerable to Andromeda."
"True."
"But it didn"t die."
"Perhaps some rapid form of immunity."
"No. Impossible. There are only two explanations. When the child stopped crying, either the organism was no longer there-had been blown away, cleared from the air-or else the organism-"
"Changed," Stone said. "Mutated."
"Yes. Mutated to a noninfectious form. And perhaps it is still mutating. Now it is no longer directly harmful to man, but it eats rubber gaskets."
"The airplane."
Hall nodded. "National guardsmen could be on the ground, and not be harmed. But the pilot had his aircraft destroyed because the plastic was dissolved before his eyes."
"So Burton is now exposed to a harmless organism. That"s why the rat is alive."
"That"s why Burton is alive," Hall said. "The rapid breathing isn"t necessary. He"s only alive because Andromeda changed."
"It may change again," Stone said. "And if most mutations occur at times of multiplication, when the organism is growing most rapidly..."
The sirens went off, and the computer flashed a message in red.
GASKET INTEGRITY ZERO. LEVEL V CONTAMINATED AND SEALED.
Stone turned to Hall. "Quick," he said, "get out of here. There"s no substation in this lab. You have to go to the next sector."
For a moment, Hall did not understand. He continued to sit in his seat, and then, when the realization hit him, he scrambled for the door and hurried outside to the corridor. As he did so he heard a hissing sound, and a thump as a ma.s.sive steel plate slid out from a wall and closed off the corridor.
Stone saw it and swore. "That does it," he said. "We"re trapped here. And if that bomb goes off, it"ll spread the organism all over the surface. There will be a thousand mutations, each killing in a different way. We"ll never be rid of it."
Over the loudspeaker, a flat mechanical voice was saying, "The level is closed. The level is closed. This is an emergency. The level is closed."
There was a moment of silence, and then a scratching sound as a new recording came on, and Miss Gladys Stevens of Omaha, Nebraska, said quietly, "There are now three minutes to atomic self-destruct."
29. Three Minutes
A NEW RISING AND FALLING SIREN CAME ON, AND all the clocks snapped their hands back to 1200 hours, and the second hands began to sweep out the time. The stop-clocks all glowed red, with a green line on the dial to indicate when detonation would occur.
And the mechanical voice repeated calmly, "There are now three minutes to self-destruct."
"Automatic," Stone said quietly. "The system cuts in when the level is contaminated. We can"t let it happen."
Hall was holding the key in his hand. "There"s no way to get to a substation?"
"Not on this level. Each sector is sealed from every other.
"But there are substations, on the other levels?"
"Yes..."
"How do I get up?"
"You can"t. All the conventional routes are sealed.
"What about the central core?" The central core communicated with all levels.
Stone shrugged. "The safeguards .
Hall remembered talking to Burton earlier about the central-core safeguards. In theory, once inside the central core you could go straight to the top. But in practice, them were ligamine sensors located around the core to prevent this. Originally intended to prevent escape of lab animals that might break free into the core, the sensors released ligamine, a curare derivative that was water-soluble, in the form of a gas. There were also automatic guns that fired ligamine darts.
The mechanical voice said, "There are now two minutes forty-five seconds to self-destruct."
Hall was already moving back into the lab and staring through the gla.s.s into the inner work area; beyond that was the central core.
Hall said, "What are my chances?"
"They don"t exist," Stone explained.
Hall bent over and crawled through a tunnel into a plastic suit. He waited until it had sealed behind him, and then he picked up a knife and cut away the tunnel, like a tail. He breathed in the air of the lab, which was cool and fresh, and laced with Andromeda organisms.
Nothing happened.
Back in the lab, Stone watched him through the gla.s.s. Hall saw his lips move, but heard nothing; then a moment later the speakers cut in and he heard Stone say, "-- best that we could devise."
"What was?"
"The defense system."
"Thanks very much," Hall said, moving toward the rubber gasket. It was circular and rather small, leading into the central core.
"There"s only one chance," Stone. said. "The doses are low. They"re calculated for a ten-kilogram animal, like a large monkey, and you weigh seventy kilograms or so. You can stand a fairly heavy dose before--"
"Before I stop breathing," Hall said. The victims of curare suffocate to death, their chest muscles and diaphragms paralyzed. Hall was certain it was an unpleasant way to die.
"Wish me luck," he said.
"There are now two minutes thirty seconds to self-destruct," Gladys Stevens said.
Hall slammed the gasket with his fist, and it crumbled in a dusty cloud. He moved out into the central core.
It was silent. He was away from the sirens and flashing lights of the level, and into a cold, metallic, echoing s.p.a.ce. The central core was perhaps thirty feet wide, painted a utilitarian gray; the core itself, a cylindrical shaft of cables and machinery, lay before him. On the walls he could see the rungs of a ladder leading upward to Level IV.
"I have you on the TV monitor, " Stone"s voice said. "Start up the ladder. The gas will begin any moment."
A new recorded voice broke in. "The central core has been contaminated," it said. "Authorized maintenance personnel are advised to clear the area immediately."
"Go!" Stone said.
Hall climbed. As he went up the circular wall, he looked back and saw pale clouds of white smoke blanketing the floor.