Hall emerged to find himself in a corridor. The was here were painted yellow, not red as they had been on Level I. The people wore yellow uniforms. A nurse by the elevator said, "The time is 2:47 p.m., gentlemen. You may continue your descent in one hour."

  They went to a small room marked INTERIM CONFINEMENT. It contained a half-dozen couches with plastic disposable covers over them.

  Stone said, "Better relax. Sleep if you can. We'll need all the rest we can get before Level V. " He walked over to Hall. "How did you find the decontamination procedure?"

  "Interesting," Hall said. "You could sell it to the Swedes and make a fortune. But somehow I expected something more rigorous."

  "Just wait," Stone said. "It gets tougher as you go. Physicals on Levels III and IV. Afterward there will be a brief conference."

  Then Stone lay down on one of the couches and fell instantly asleep. It was a trick he had learned years before, when he had been conducting experiments around the clock. He learned to squeeze in an hour here, two hours there. He found it useful.

  ***

  The second decontamination procedure was similar to the first. Hall's yellow clothing, though he had worn it just an hour, was incinerated.

  "Isn't that rather wasteful?" he asked Burton.

  Burton shrugged. "It's paper."

  "Paper? That cloth?"

  Burton shook his head. "Not cloth. Paper. New process."

  They stepped into the first total-immersion pool. Instructions on the wall told Hall to keep his eyes open under water. Total immersion, he soon discovered, was guaranteed by the simple device of making the connection between the first room and the second an underwater passage. Swimming through, he felt a slight burning of his eyes, but nothing bad.

  The second room contained a row of six boxes, glass-walled, looking rather like telephone booths. Hall approached one and saw a sign that said, "Enter and close both eyes. Hold arms slightly away from body and stand with feet one foot apart. Do not open eyes until buzzer sounds. BLINDNESS MAY RESULT FROM EXPOSURE TO LONG-WAVE RADIATION."

  He followed the directions and felt a kind of cold heat on his body. It lasted perhaps five minutes, and then he heard the buzzer and opened his eyes. His body was dry. He followed the others to a corridor, consisting of four showers. Walking down the corridor, he passed beneath each shower in turn. At the end, he found blowers, which dried him, and then clothing. This time the clothing was white.

  They dressed, and took the elevator down to Level III.

  ***

  There were four nurses waiting for them; one took Hall to an examining room. It turned out to be a two-hour physical examination, given not by a machine but by a blank-faced, thorough young man. Hall was annoyed, and thought to himself that he preferred the machine.

  The doctor did everything, including a complete history birth, education, travel, family history, past hospitalizations and illnesses. And an equally complete physical. Hall became angry; it was all so damned unnecessary. But the doctor shrugged and kept saying, "It's routine."

  After two hours, he rejoined the others, and proceeded to Level IV.

  ***

  Four total-immersion baths, three sequences of ultraviolet and infrared light, two of ultrasonic vibrations, and then something quite astonishing at the end. A steel-walled cubicle, with a helmet on a peg. The sign said, "This is an ultraflash apparatus. To protect head and facial hair, place metal helmet securely on head, then press button below."

  Hall had never heard of ultraflash, and he followed directions, not knowing what to expect. He placed the helmet over his head, then pressed the button.

  There was a single, brief, dazzling burst of white light, followed by a wave of heat that filled the cubicle. He felt a moment of pain, so swift he hardly recognized it until it was over. Cautiously, he removed the helmet and looked at his body. His skin was covered with a fine, white ash-- and then he realized that the ash was his skin, or had been: the machine had burned away the outer epithelial layers. He proceeded to a shower and washed the ash off. When he finally reached the dressing room, he found green uniforms.

  ***

  Another physical. This time they wanted samples of everything: sputum, oral epithelium, blood, urine, stool. He submitted passively to the tests, examinations, questions. He was tired, and was beginning to feel disoriented. The repetitions, the new experiences, the colors on the walls, the same bland artificial light...

  Finally, he was brought back to Stone and the others. Stone said, "We have six hours on this level-- that's protocol, waiting while they do the lab tests on us-- so we might as well sleep. Down the corridor are rooms, marked with your names. Further down is the cafeteria. We'll meet there in five hours for a conference. Right?"

  Hall found his room, marked with a plastic door tag. He entered, surprised to find it quite large. He had been expecting something the size of a Pullman cubicle, but this was bigger and better-furnished. There was a bed, a chair, a small desk, and a computer console with built-in TV set. He was curious about the computer, but also very tired. He lay down on the bed and fell asleep quickly.

  ***

  Burton could not sleep. He lay in his bed on Level IV and stared at the ceiling, thinking. He could not get the image of that town out of his mind, or those bodies, lying in the street without bleeding...

  Burton was not a hematologist, but his work had involved some blood studies. He knew that a variety of bacteria had effects on blood. His own research with staphylococcus, for example, had shown that this organism produced two enzymes that altered blood.

  One was the so-called exotoxin, which destroyed skin and dissolved red cells. Another was a coagulase, which coated the bacteria with protein to inhibit destruction by white cells.

  So it was possible that bacteria could alter blood. And it could do it many different ways: strep produced an enzyme, streptokinase, that dissolved coagulated plasma. Clostridia and pneumococci produced a variety of hemolysins that destroyed red cells. Malaria and amebae also destroyed red cells, by digesting them as food. Other parasites did the same thing.

  So it was possible.

  But it didn't help them in finding out how the Scoop organism worked.

  Burton tried to recall the sequence for blood clotting. He remembered that it operated like a kind of waterfall: one enzyme was set off, and activated, which acted on a second enzyme, which acted on a third; the third on a fourth; and so on, down through twelve or thirteen steps, until finally blood clotted.

  And vaguely he remembered the rest, the details: all the intermediate steps, the necessary enzymes, the metals, ions, local factors. It was horribly complex.

  He shook his head and tried to sleep.

  ***

  Leavitt, the clinical microbiologist, was thinking through the steps in isolation and identification of the causative organism. He had been over it before; he was one of die original founders of the group, one of the men who developed the Life Analysis Protocol. But now, on the verge of putting that plan into effect, he had doubts.

  Two years before, sitting around after lunch, talking speculatively, it had all seemed wonderful. It had been an amusing intellectual game then, a kind of abstract test of wits. But now, faced with a real agent that caused real and bizarre death, he wondered whether all their plans would prove to be so effective and so complete as they once thought.

  The first steps were simple enough. They would examine the capsule minutely and culture everything onto growth media. They would be hoping like hell to come up with an organism that they could work with, experiment on, and identify.

  And after that, attempt to find out how it attacked. There was already the suggestion that it killed by clotting the blood; if that turned out to be the case, they had a good start, but if not, they might waste valuable time following it up.

  The example of cholera came to mind. For centuries, men had known that cholera was a fatal disease, and that it caused severe diarrhea, sometimes producing as much as thirty quarts of fluid a day. Men knew this, but they somehow assumed that the lethal effects of the disease were unrelated to the diarrhea; they searched for something else: an antidote, a drug, a way to kill the organism. It was not until modern times that cholera was recognized as a disease that killed through dehydration primarily; if you could replace a victim's water losses rapidly, he would survive the infection without other drugs or treatment.

  Cure the symptoms, cure the disease.

  But Leavitt wondered about the Scoop organism. Could they cure the disease by treating the blood clotting? Or was the clotting secondary to some more serious, disorder?

  There was also another concern, a nagging fear that had bothered him since the earliest planning stages of Wildfire. In those early meetings, Leavitt had argued that the Wildfire team might be committing extraterrestrial murder.

  Leavitt had pointed out that all men, no matter how scientifically objective, had several built-in biases when discussing life. One was the assumption that complex life was larger than simple life. It was certainly true on the earth. As organisms became more intelligent, they grew larger, passing from the single-celled stage to multicellular creatures, and then to larger animals with differentiated cells working in groups called organs. On earth, the trend had been toward larger and more complex animals.

  But this might not be true elsewhere in the universe. In other places, life might progress in the opposite direction-- toward smaller and smaller forms. Just as modern human technology had learned to make things smaller, perhaps highly advanced evolutionary pressures led to smaller life forms. There were distinct advantages to smaller forms: less consumption of raw materials, cheaper spaceflight, fewer feeding problems...

  Perhaps the most intelligent life form on a distant planet was no larger than a flea. Perhaps no larger than a bacterium. In that case, the Wildfire Project might be committed to destroying a highly developed life form, without ever realizing what it was doing.

  This concept was not unique to Leavitt. It had been proposed by Merton at Harvard, and by Chalmers at Oxford. Chalmers, a man with a keen sense of humor, had used the example of a man looking down on a microscope slide and see in the bacteria formed into the words "Take us to your leader." Everyone thought Chalmers's idea highly amusing.

  Yet Leavitt could not get it out of his mind. Because it just might turn out to be true.

  ***

  Before he fell asleep, Stone thought about the conference coming up. And the business of the meteorite. He wondered what Nagy would say, or Karp, if they knew about the meteorite.

  Probably, he thought, it would drive them insane. Probably it will drive us all insane.

  And then he slept.

  ***

  Delta sector was the designation of three rooms on Level I that contained all communications facilities for the Wildfire installation. All intercom and visual circuits between levels were routed through there, as were cables for telephone and teletype from the outside. The trunk lines to the library and the central storage unit were also regulated by delta sector.

  In essence it functioned as a giant switchboard, fully computerized. The three rooms of delta sector were quiet; all that could be heard was the soft hum of spinning tape drums and the muted clicking of relays. Only one person worked here, a single man sitting at a console, surrounded by the blinking lights of the computer.

  There was no real reason for the man to be there; he performed no necessary function. The computers were self-regulating, constructed to run check patterns through their circuits every twelve minutes; the computers shut down automatically if there was an abnormal reading.

  According to protocol, the man was required to monitor MCN communications, which were signaled by the ringing of a bell on the teleprinter. When the bell rang, he notified the five level command centers that the transmission was received. He was also required to report any computer dysfunction to Level I command, should that unlikely event occur.

  DAY 3

  Wildfire

  12. The Conference

  "TIME TO WAKE UP, SIR."

  Mark Hall opened his eyes. The room was lit with a steady, pale fluorescent light. He blinked and rolled over on his stomach.

  "Time to wake up, Sir."

  It was a beautiful female voice, soft and seductive. He sat up in bed and looked around the room: he was alone.

  "Hello?"

  "Time to wake up, Sir."

  "Who are you?"

  "Time to wake up, Sir."

  He reached over and pushed a button on the nightstand by his bed. A light went off. He waited for the voice again, but it did not speak.

  It was, he thought, a hell of an effective way to wake a man up. As he slipped into his clothes, he wondered how it worked. It was not a simple tape, because it worked as a response of some sort. The message was repeated only when Hall spoke.

  To test his theory, he pushed the nightstand button again. The voice said softly, "Do you wish something, Sir?"

  "I'd like to know your name, please."

  "Will that be all, Sir?"

  "Yes, I believe so."

  "Will that be all, Sir?"

  He waited. The light clicked off. He slipped into his shoes and was about to leave when a male voice said, "This is the answering-service supervisor, Dr. Hall. I wish you would treat the project more seriously."

  Hall laughed. So the voice responded to comments, and taped his replies. It was a clever system.

  "Sorry," he said, "I wasn't sure how the thing worked. The voice is quite luscious."

  "The voice," said the supervisor heavily, "belongs to Miss Gladys Stevens, who is sixty-three years old. She lives in Omaha and makes her living taping messages for SAC crews and other voice-reminder systems."

  "Oh," Hall said.

  He left the room and walked down the corridor to the cafeteria. As he walked, he began to understand why submarine designers had been called in to plan Wildfire. Without his wristwatch, he had no idea of the time, or even whether it was night or day. He found himself wondering whether the cafeteria would be crowded, wondering whether it was dinner time or breakfast time.

  As it turned out, the cafeteria was almost deserted. Leavitt was there; he said the others were in the conference room. He pushed a glass of dark-brown liquid over to Hall and suggested he have breakfast.

  "What's this?" Hall said.

  "Forty-two-five nutrient. It has everything needed to sustain the average seventy-kilogram man for eighteen hours."

  Hall drank the liquid, which was syrupy and artificially flavored to taste like orange juice. It was a strange sensation, drinking brown orange juice, but not bad after the initial shock. Leavitt explained that it had been developed for the astronauts, and that it contained everything except air-soluble vitamins.

  "For that, you need this pill," he said.

  Hall swallowed the pill, then got himself a cup of coffee from a dispenser in the corner. "Any sugar?"

  Leavitt shook his head. "No sugar anywhere here. Nothing that might provide a bacterial growth medium. From now on, we're all on high-protein diets. We'll make all the sugar we need from the protein breakdown. But we won't be getting any sugar into the gut. Quite the opposite."

  He reached into his pocket.

  "Oh, no."

  "Yes," Leavitt said. He gave him a small capsule, sealed in aluminum foil.

  "No," Hall said.

  "Everyone else has them. Broad-spectrum. Stop by your room and insert it before you go into the final decontamination procedures."

  "I don't mind dunking myself in all those foul baths," Hall said. "I don't mind being irradiated. But I'll be goddammed--"

  "The idea," Leavitt said, "is that you be as nearly sterile as possible on Level V. We have sterilized your skin and mucous membranes of the respiratory tract as best we can. But we haven't done a thing about the GI tract yet."

  "Yes," Hall said, "but suppositories?"

  "You'll get used to it. We're all taking them for the first four days. Not, of course, that they'll do any good," he said, with the familiar wry, pessimistic look on his face. He stood. "Let's go to the conference room. Stone wants to talk about Karp."

  "Who?"

  "Rudolph Karp."

  ***

  Rudolph Karp was a Hungarian-born biochemist who came to the United States from England in 1951. He obtained a position at the University of Michigan and worked steadily and quietly for five years. Then, at the suggestion of colleagues at the Ann Arbor observatory, Karp began to investigate meteorites with the intent of determining whether they harbored life, or showed evidence of having done so in the past. He took the proposal quite seriously and worked with diligence, writing no papers on the subject until the early 1960's, when Calvin and Vaughn and Nagy and others were writing explosive papers on similar subjects.

  The arguments and counter-arguments were complex, but boiled down to a simple substrate: whenever a worker would announce that he had found a fossil, or a proteinaceous hydrocarbon, or other indication of life within a meteorite, the critics would claim sloppy lab technique and contamination with earth-origin matter and organisms.

  Karp, with his careful, slow techniques, was determined to end the arguments once and for all. He announced that he had taken great pains to avoid contamination: each meteorite he examined had been washed in twelve solutions, including peroxide, iodine, hypertonic saline and dilute acids. It was then exposed to intense ultraviolet light for a period of two days. Finally, it was submerged in a germicidal solution and placed in a germ-free, sterile isolation chamber; further work was done within the chamber.

  Karp, upon breaking open his meteorites, was able to isolate bacteria. He found that they were ring-shaped organisms, rather like a tiny undulating inner tube, and he found they could grow and multiply. He claimed that, while they were essentially similar to earthly bacteria in structure, being based upon proteins, carbohydrates, and lipids, they had no cell nucleus and therefore their manner of propagation was a mystery.

  Karp presented his information in his usual quiet, unsensational manner, and hoped for a good reception. He did not receive one; instead, he was laughed down by the Seventh Conference of Astrophysics and Geophysics, meeting in London in 1961. He became discouraged and set his work with meteorites aside; the organisms were later destroyed in an accidental laboratory explosion on the night of June 27, 1963.

  Karp's experience was almost identical to that of Nagy and the others. Scientists in the 1960's were not willing to entertain notions of life existing in meteorites; all evidence presented was discounted, dismissed, and ignored.

  A handful of people in a dozen countries remained intrigued, however. One of them was Jeremy Stone; another was Peter Leavitt. It was Leavitt who, some years before, had formulated the Rule of 48. The Rule of 48 was intended as a humorous reminder to scientists, and referred to the massive literature collected in the late 1940's and the 1950's concerning the human chromosome number.

  For years it was stated that men had forty-eight chromosomes in their cells; there were pictures to prove it, and any number of careful studies. In 1953, a group of American researchers announced to the world that the human chromosome number was forty-six. Once more, there were pictures to prove it, and studies to confirm it. But these researchers also went back to reexamine the old pictures, and the old studies-- and found only forty-six chromosomes, not forty-eight.

  Leavitt's Rule of 48 said simply, "All Scientists Are Blind." And Leavitt had invoked his rule when he saw the reception Karp and others received. Leavitt went over the reports and the papers and found no reason to reject the meteorite studies out of hand; many of the experiments were careful, well-reasoned, and compelling.

  He remembered this when he and the other Wildfire planners drew up the study known as the Vector Three. Along with the Toxic Five, it formed one of the firm theoretical bases for Wildfire.

  The Vector Three was a report that considered a crucial question: If a bacterium invaded the earth, causing a new disease, where would that bacterium come from?

  After consultation with astronomers and evolutionary theories, the Wildfire group concluded that bacteria could come from three sources.

  The first was the most obvious-- an organism, from another planet or galaxy, which had the protection to survive the extremes of temperature and vacuum that existed in space. There was no doubt that organisms could survive-- there was, for instance, a class of bacteria known as thermophilic that thrived on extreme heat, multiplying enthusiastically in temperatures as high as 70deg C. Further, it was known that bacteria had been recovered from Egyptian tombs, where they had been sealed for thousands of years. These bacteria were still viable.

  The secret lay in the bacteria's ability to form spores, molding a hard calcific shell around themselves. This shell enabled the organism to survive freezing or boiling, and, if necessary, thousands of years without food. It combined all the advantages of a space suit with those of suspended animation.

  There was no doubt that a spore could travel through space. But was another planet or galaxy the most likely source of contamination for the earth?

  Here, the answer was no. The most likely source was the closest source-- the earth itself.

  The report suggested that bacteria could have left the surface of the earth eons ago, when life was just beginning to emerge from the oceans and the hot, baked continents. Such bacteria would depart before the fishes, before the primitive mammals, long before the first ape-man. The bacteria would head up into the air, and slowly ascend until they were literally in space. Once there, they might evolve into unusual forms, perhaps even learning to derive energy for life directly from the sun, instead of requiring food as an energy source. These organisms might also be capable of direct conversion of energy to matter.

  Leavitt himself suggested the analogy of the upper atmosphere and the depths of the sea as equally inhospitable environments, but equally viable. In the deepest, blackest regions of the oceans, where oxygenation was poor, and where light never reached, life forms were known to exist in abundance. Why not also in the far reaches of the atmosphere? True, oxygen was scarce. True, food hardly existed. But if creatures could live miles beneath the surface, why could they not also live five miles above it?

  And if there were organisms out there, and if they had departed from the baking crust of the earth long before the first men appeared, then they would be foreign to man. No immunity, no adaptation, no antibodies would have been developed. They would be primitive aliens to modern man, in the same way that the shark, a primitive fish unchanged for a hundred million years, was alien and dangerous to modern man, invading the oceans for the first time.

  The third source of contamination, the third of the vectors, was at the same time the most likely and the most troublesome. This was contemporary earth organisms, taken into space by inadequately sterilized spacecraft. Once in space, the organisms would be exposed to harsh radiation, weightlessness, and other environmental forces that might exert a mutagenic effect, altering the organisms.

  So that when they came down, they would be different.

  Take up a harmless bacteria-- such as the organism that causes pimples, or sore throats-- and bring it back in a new form, virulent and unexpected. It might do anything. It might show a preference for the aqueous humor of the inner eye, and invade the eyeball. It might thrive on the acid secretions of the stomach. It might multiply on the small currents of electricity afforded by the human brain itself, drive men mad.

  This whole idea of mutated bacteria seemed farfetched and unlikely to the Wildfire people. It is ironic that this should be the case, particularly in view of what happened to the Andromeda Strain. But the Wildfire team staunchly ignored both the evidence of their own experience-- that bacteria mutate rapidly and radically-- and the evidence of the Biosatellite tests, in which a series of earth forms were sent into space and later recovered.

  Biosatellite II contained, among other things, several species of bacteria. It was later reported that the bacteria had reproduced at a rate twenty to thirty times normal. The reasons were still unclear, but the results unequivocal: space could affect reproduction and growth.

  And yet no one in Wildfire paid attention to this fact, until it was too late.

  ***

  Stone reviewed the information quickly, then handed each of them a cardboard file. "These files," he said, "contain a transcript of autoclock records of the entire flight of Scoop VII. Our purpose in reviewing the transcript is to determine,

  if possible, what happened to the satellite while it was in orbit."

  Hall said, "Something happened to it?"

  Leavitt explained. "The satellite was scheduled for a six-day orbit, since the probability of collecting organisms is proportional to time in orbit. After launch, it was in stable orbit. Then, on the second day, it went out of orbit.

  Hall nodded.

  "Start," Stone said, "with the first page."

  Hall opened his file.

  AUTOCLOCK TRANSCRIPT

  PROJECT: SCOOP VII

  LAUNCHDATE:

  ABRIDGED VERSION. FULL TRANSCRIPT

  STORED VAULTS 179-99,

  VDBG COMPLEX EPSILON.

  HOURS MIN SEC PROCEDURE

  T MINUS TIME

  0002 01 05 Vandenberg Launch pad Block 9, Scoop Mission Control, reports systems check on schedule.

  0001 39 52 Scoop MC holds for fuel check reported from Ground Control.

  STOP CLOCK STOP CLOCK. REALTIME LOSS 12 MINUTES.

  0001 39 52 Count resumed. Clock corrected.

  0000 41 12 Scoop MC holds 20 seconds for Launch pad Block 9 check. Clock not stopped for built-in hold.