Obviously the Andromeda Strain showed a predilection for cerebral vasculature. It was impossible to say why, but it was known that the cerebral vessels are peculiar in several respects. For instance, under circumstances in which normal body vessels dilate or contract- such as extreme cold, or exercise- the brain vasculature does not change, but maintains a steady, constant blood supply to the brain.

In exercise, the blood supply to muscle might increase five to twenty times. But the brain always has a steady flow: whether its owner is taking an exam or a nap, chopping wood or watching TV. The brain receives the same amount of blood every minute, hour, day.

The scientists did not know why this should be, or how, precisely, the cerebral vessels regulate themselves. But the phenomenon is known to exist, and cerebral vessels are regarded as a special case among the body's arteries and veins. Clearly, something is different about them.

And now there was an example of an organism that destroyed them preferentially.

But as Burton thought about it, the action of Andromeda did not seem so unusual. For example, syphilis causes an inflammation of the aorta, a very specific, peculiar reaction. Schistosomiasis, a parasitic infection, shows a preference for bladder, intestine, or colonic vessels- depending on the species. So such specificity was not impossible.

"But there's another problem," he said. "In most people, the organism begins clotting at the lungs. We know that. Presumably vessel destruction begins there as well. What is different about-"

He stopped.

He remembered the rats he had anticoagulated. The ones who had died anyway, but had had no autopsies.

"My God," he said.

He drew out one of the rats from cold storage and cut it open. It bled. Quickly he incised the head, exposing the brain. There he found a large hemorrhage over the gray surface of the brain.

"You've got it," Hall said.

"If the animal is normal, it dies from coagulation, beginning at the lungs. But if coagulation is prevented, then the organism erodes through the vessels of the brain, and hemorrhage occurs."

"And insanity."

"Yes." Burton was now very excited. "And coagulation could be prevented by any blood disorder. Or too little vitamin K. Malabsorption syndrome. Poor liver function. Impaired protein synthesis. Any of a dozen things."

"All more likely to be found in an old person," Hall said.

"Did Jackson have any of those things?"

Hall took a long time to answer, then finally said, "No. He has liver disease, but not significantly."

Burton sighed. "Then we're back where we started.

"Not quite. Because Jackson and the baby both survived. They didn't hemorrhage- as far as we know- they survived untouched. Completely untouched."

"Meaning?"

"Meaning that they somehow prevented the primary process, which is invasion of the organism into the vessel walls of the body. The Andromeda organism didn't get to the lungs, or the brain. It didn't get anywhere."

"But why?"

"We'11 know that," Hall said, "when we know why a sixty-nine-year-old Sterno drinker with an ulcer is like a two-month-old baby."

"They seem pretty much opposites," Burton said.

"They do, don't they?" Hall said. It would be hours before, he realized Burton had given him the answer to the puzzle- but an answer that was worthless.

SIR WINSTON CHURCHILL ONCE SAID THAT TRUE genius resides in the capacity for evaluation of uncertain, hazardous, and conflicting information." Yet it is a peculiarity of the Wildfire team that, despite the individual brilliance of team members, the group grossly misjudged their information at several points.

One is reminded of Montaigne's acerbic comment: "Men under stress are fools, and fool themselves." Certainly the Wildfire team was under severe stress, but they were also prepared to make mistakes. They had even predicted that this would occur.

What they did not anticipate was the magnitude, the staggering dimensions of their error. They did not expect that their ultimate error would be a compound of a dozen small clues that were missed, a handful of crucial facts that were dismissed.

The team had a blind spot, which Stone later expressed this way: "We were problem-oriented. Everything we did and thought was directed toward finding a solution, a cure to Andromeda. And, of course, we were fixed on the events that had occurred at Piedmont. We felt that if we did not find a solution, no solution would be forthcoming, and the whole world would ultimately wind up like Piedmont. We were very slow to think otherwise."

The error began to take on major proportions with the cultures.

Stone and Leavitt had taken thousands of cultures from the original capsule. These had been incubated in a wide variety of atmospheric, temperature, and pressure conditions. The results of this could only be analyzed by computer.

Using the GROWTH/TRANSMATRIX program, the computer did not print out results from all possible growth combinations. Instead, it printed out only significant positive and negative results. It did this after first weighing each petri dish, and examining any growth with its photoelectric eye.

When Stone and Leavitt went to examine the results, they found several striking trends. Their first conclusion was that growth media did not matter at all- the organism grew equally well on sugar, blood, chocolate, plain agar, or sheer glass.

However, the gases in which the plates were incubated were crucial, as was the light.

Ultraviolet light stimulated growth under all circumstances. Total darkness, and to a lesser extent infrared light, inhibited growth.

Oxygen inhibited growth in all circumstances, but carbon dioxide stimulated growth. Nitrogen had no effect.

Thus, best growth was achieved in 100-per cent carbon dioxide, lighted by ultraviolet radiation. Poorest growth occurred in pure oxygen, incubated in total darkness.

"What do you make of it?" Stone said.,

"It looks like a pure conversion system," Leavitt said.

"I wonder," Stone said.

He punched through the coordinates of a closed-growth system. Closed-growth systems studied bacterial metabolism by measuring intake of gases and nutrients, and output of waste products. They were completely sealed and self-contained. A plant in such a system, for example, would consume carbon dioxide and give off water and oxygen.

[GRAPHIC: An example of a scanner printout from the photoelectric eye that examined all growth media. Within the circular petri dish the computer has noted the presence of two separate colonies. The colonies are "read" in two-millimeter-square segments, and graded by density on a scale from one to nine.]

But when they looked at the Andromeda Strain, they found something remarkable. The organism had no excretions. If incubated with carbon dioxide and ultraviolet light, it grew steadily until all carbon dioxide had been consumed. Then growth stopped. There was no excretion of any kind of gas or waste product at all.

No waste.

"Clearly efficient," Stone said.

"You'd expect that," Leavitt said.

This was an organism highly suited to its environment. It consumed everything, wasted nothing. It was perfect for the barren existence of space.

He thought about this for a moment, and then it hit him. It hit Leavitt at the same time.

"Oh my hell."

Leavitt was already reaching for the phone. "Get Robertson," he said. "Get him immediately."

"Incredible," Stone said softly. "No waste. It doesn't require growth media. It can grow in the presence of carbon, oxygen, and sunlight. Period."

"I hope we're not too late," Leavitt said, watching the computer console screen impatiently.

Stone nodded. "If this organism is really converting matter to energy, and energy to matter- directly- then it's functioning like a little reactor."

"And an atomic detonation."

"Incredible," Stone said. "Just incredible."

The screen came to life; they saw Robertson, looking tired, smoking a cigarette.

"Jeremy, you've got to give me time. I haven't been able to get through to-"

Listen," Stone said, "I want you to make sure Directive 7-12 is not carried out. It is imperative: no atomic device must be detonated around the organisms. That's the last thing in the world, literally, that we want to do."

He explained. briefly what he had found.

Robertson whistled. "We'd just provide a fantastically rich growth medium.

"That's right," Stone said.

The problem of a rich growth medium was a peculiarly distressing one to the Wildfire team. It was known, for example, that checks and balances exist in the normal environment. These manage to dampen the exuberant growth of bacteria.

The mathematics of uncontrolled growth are frightening. A single cell of the bacterium E. coli would, under ideal circumstances, divide every twenty minutes. That is not particularly disturbing until you think about it, but the fact is that bacteria multiply geometrically: one becomes two, two become four, four become eight, and so on. In this way, it can be shown that in a single day, one cell of E. coli could produce a super-colony equal in size and weight to the entire planet earth.

This never happens, for a perfectly simple reason: growth cannot continue indefinitely under "ideal circumstances." Food runs out. Oxygen runs out. Local conditions within the colony change, and check the growth of organisms.

On the other hand, if you had an organism that was capable of directly converting energy to matter, and if you provided it with a huge rich source of energy, like an atomic blast…

"I'll pass along your recommendation to the President," Robertson said. "He'll be pleased to know he made the right decision on the 7-12."

"You can congratulate him on his scientific insight, " Stone said, "for me."

Robertson was scratching his head. "I've got some more data on the Phantom crash. It was over the area west of Piedmont at twenty-three thousand feet. The post team has found evidence of the disintegration the pilot spoke of, but the material that was destroyed was a plastic of some kind. It was depolymerized."

"What does the post team make of that?"