On the third morning, Peter Halpern walked out of the hospital.
He did not accomplish it with quite the independence he had been promising Nathan for the previous two days, but he walked nonetheless, and considering the condition he had been in when Nathan first stood beside his bed, the distinction hardly seemed worth arguing over.
Morning had come slowly to the ward, first as a weak grey light against the tall windows and then as a gradual brightening of the room that made the electric lamps seem unnecessary without anyone bothering to switch them off. Beyond the glass, Chicago was already making itself heard. Streetcars rang their bells somewhere among the buildings, wagons rattled over the road, and every so often the harsher note of a motor horn pushed through the older sounds of hooves and wheels. The hospital kept its own hours, however, and had been awake long before the city properly announced itself. Breakfast trays were being collected from between the beds, enamel basins carried away and returned, sheets folded, medicines measured, temperatures taken and written down. An orderly manoeuvred a trolley of clean linen along the central aisle while apologising to everyone he nearly struck with it, and one of the nurses had spent the better part of five minutes attempting to persuade an elderly patient that his spectacles were not missing but sitting on top of his head. The smell of porridge and weak coffee lingered beneath carbolic disinfectant, soap, boiled linen and the less easily named human warmth of a ward in which too many people had spent the night feverish.
Through all of it came the coughing. Nathan had ceased noticing every individual instance sometime during his second day there, but he had not ceased hearing it. A dry cough from behind one screen answered a deeper, wetter one several beds away, while farther down the ward somebody entered a prolonged fit that caused a nurse to stop what she was doing and disappear behind a partition. The sound belonged to the place now as thoroughly as the clink of glass and metal or the quiet conversations of relatives beside beds.
Peter , for his part, appeared determined to leave before anyone discovered a reason to keep him.
"I can do it," he insisted when his mother reached for the sleeve of his coat, pulling his arm away with the affronted dignity of a boy whose competence had been publicly questioned. The sleeve had somehow twisted behind him, and his first attempt only succeeded in pushing the lining farther out of place, but he refused Mrs Halpern's second offer of assistance and twisted his shoulder until his hand finally emerged through the cuff. The effort ruined whatever order his mother had managed to impose upon his hair, and when he looked immediately towards Nathan, there was such obvious expectation on his face that Nathan understood recognition of the achievement had become part of his professional duties.
"So I see," Nathan replied from beside the bed, folding the discharge papers once before offering them to Mrs Halpern. "An extraordinary medical recovery. Yesterday you required assistance crossing six feet of floor, and today you've successfully defeated a coat. I shall have to write a paper."
"It was stuck," Peter protested, pulling the sleeve straight while his mother took the papers from Nathan and tried not to smile.
"Naturally," Nathan said, giving the offending garment a grave inspection. "A particularly vicious specimen."
"It was."
"I believe you completely."
Peter narrowed his eyes at him. Three days in Nathan's company had taught him exactly how much confidence to place in that particular tone, though not yet how to answer it effectively.
The illness had left its mark despite the boy's determination to behave as though it had not. Three days of fever and enforced bed rest had thinned Peter's face, and there was still a faint pallor beneath his skin that Nathan expected would take several days of proper meals, sleep and maternal supervision to disappear. His strength lagged farther behind his confidence than Peter realised, although Nathan suspected he would discover that soon enough. What mattered was that the dangerous heat had gone from him. His temperature had remained down through the night, his breathing was clear, and the cough that remained was infrequent and dry. Most encouragingly, breakfast had finally been eaten rather than pushed around the plate until Peter could claim there was less of it. Nathan had inspected the tray himself that morning and found only a smear of porridge, half a crust and the remains of an argument over whether milk counted as food.
More importantly, Nathan knew something nobody else in the ward could possibly know.
The infection had lost.
He had examined Peter carefully that morning and found no reason to interfere again. The tiny advantage Nathan had given him through Red-Light had done what it was intended to do. He had not removed the virus from Peter's body, although he could have, nor had he replaced the boy's immune response with something stronger and less human. That would have produced a recovery too clean to trust and, perhaps, too unusual to explain. Instead Nathan had interfered at the margins, denying the infection some of its early success, restricting enough replication to buy Peter's own defences time to organise themselves and then allowing the contest to proceed without him.
Now Peter's body was winning it honestly.
As far as every physician in Chicago would ever know, Peter Halpern had contracted influenza, endured several unpleasant days of fever and weakness and recovered naturally.
Nathan intended that history to remain exactly that simple.
Mrs Halpern unfolded the discharge instructions and read the first few lines while Peter continued wrestling with the buttons of his coat. She looked almost as changed as her son, though exhaustion remained around her eyes and in the way she occasionally rubbed one thumb against the side of her forefinger without seeming aware of it. Nathan had watched the fear leave her by degrees rather than all at once. On the first morning she had followed every physician entering the ward with her eyes, studying faces before anyone spoke to her, and whenever Peter coughed she had stopped whatever she was doing until the sound passed. The following afternoon Nathan had found her reading beside the bed while Peter slept, but even then she had rarely managed more than a page before glancing over the top of the book to check that his chest was still rising normally.
That morning she had arrived carrying his clothes.
It was the first time Nathan had seen her enter the ward looking like a woman who genuinely expected to leave it with her son.
"Keep him quiet for several days," Nathan told her, tapping one finger against the instructions in her hand before looking towards Peter. "And when I say quiet, I mean the ordinary definition of the word, not whatever definition you're currently constructing for your own convenience."
"I wasn't saying anything," Peter replied, finally fastening the top button and looking pleased with himself.
"You were thinking loudly."
Mrs Halpern laughed under her breath before looking back towards Nathan. "Can he go outside?"
"Certainly. Fresh air won't hurt him, provided he isn't exhausted and the weather behaves itself. I wouldn't send him running halfway across Chicago just yet, and if the fever comes back, if his breathing becomes difficult or if that cough worsens instead of improving, bring him straight back." Nathan saw her fingers tighten around the papers at the mention of breathing and deliberately kept his tone matter-of-fact as he continued. "Otherwise, food whenever he'll tolerate it, plenty to drink and more sleep than he'll admit he needs."
"I don't get tired," Peter said, turning from the bed with an expression of complete certainty.
Nathan looked at him.
Mrs Halpern looked at him.
A nurse passing with a tray slowed just enough to enjoy what happened next.
Peter endured the combined scrutiny for perhaps three seconds before the certainty began to collapse. "Not very tired," he amended.
"Remarkable progress already," Nathan murmured, and the nurse continued along the aisle smiling to herself.
Mrs Halpern shook her head and reached to straighten Peter's collar, ignoring the small noise of protest he made when she did. Nathan watched her fingers linger there for a moment after the collar was already corrected. She had done things like that constantly during the previous three days—touching Peter's hair, adjusting blankets that did not require adjustment, taking his hand while he slept—and Nathan understood the impulse well enough not to notice it aloud.
She had already lost one son.
Her younger boy had died of pneumonia two years earlier.
Nathan had learned that on Peter's first day in the hospital, but knowing it as an item in a family history and seeing what the memory did to Mrs Halpern were different things. When Peter's fever rose and his breathing worsened, she had not entered the hospital merely afraid of influenza. She had entered carrying another bedside with her, another child's breathing becoming more difficult while adults around her tried to sound reassuring, another morning on which she had eventually gone home without the boy she had brought in.
Peter's recovery could not erase that memory.
It could, Nathan hoped, prevent another from joining it.
Peter slid carefully from the edge of the bed, planting both shoes on the floor before straightening. For an instant he stood perfectly still, and Nathan saw the uncertainty cross his face before Mrs Halpern did. Illness had retreated far enough for confidence to return faster than strength, and when Peter attempted his first step his right knee softened beneath him.
Nathan's hand closed around his upper arm before he could fall.
He did not catch him dramatically or lift him back onto the bed. Doing either would have frightened Mrs Halpern and humiliated Peter. Instead Nathan simply gave the boy enough support to recover his balance and waited until both feet were properly beneath him again.
"Easy," he said, keeping his hand where it was until Peter straightened. "Nobody is timing you."
"I can walk," Peter muttered, his cheeks colouring as he looked down at his shoes.
"I know you can," Nathan replied, loosening his grip. "So walk."
Peter did.
This time Nathan kept one hand loosely behind his shoulder while Mrs Halpern moved to the other side, and together they began making their way towards the end of the ward. Peter's first few steps were careful enough that he seemed to be considering each one before committing to it, but the awkwardness faded as his legs remembered what was expected of them. After several yards he refused his mother's arm and continued under his own power, although he permitted Nathan's hand to remain near his shoulder, apparently having decided that accepting help and admitting he was accepting help were two entirely different matters.
They passed the bed where Nathan had first examined him.
Fresh linen had already been folded beside it.
The mattress was bare.
Nathan's attention remained on it for a moment longer than it should have.
Hospitals did not have the luxury of sentimentality about beds. Someone recovered, someone died, someone left, and the sheets came away. The mattress was cleaned, new linen appeared, and before long another person occupied the space. Within an hour there might be another feverish child beneath those blankets, another frightened mother sitting in Mrs Halpern's chair and another chart hanging where Peter's had been.
Nathan understood the necessity perfectly.
He disliked it anyway.
An orderly with an armful of folded sheets stopped to let them pass, recognised Peter and gave him an approving nod. "Escaping, are you?"
"They finally realised they couldn't keep me," Peter replied, and the orderly looked towards Nathan with an expression suggesting he had already heard enough of Peter during the previous three days to believe it.
"Terrible loss to the institution," Nathan said.
"Devastating," the orderly agreed before continuing towards the empty bed.
Peter looked pleased with himself.
By the time they reached the ward doors his stride had improved enough that Mrs Halpern had to remind him there was no prize for reaching the entrance first. Nathan accompanied them through the doors and continued down the corridor farther than was strictly necessary. He knew that. From the brief look Mrs Halpern gave him when they turned towards the main entrance, he suspected she knew it too.
Neither of them mentioned it.
The hospital beyond the ward had become busier while they were packing Peter's things. An orderly pushed a trolley piled high with linen around a corner and apologised when one wheel nearly clipped Nathan's shoe. Two nurses stood over a desk comparing medication orders while a telephone rang unanswered behind them, and farther along a physician with his coat unbuttoned was attempting to extract a coherent history from an elderly man whose answer to every question apparently required a preamble beginning sometime before the war. A woman holding a little girl's hand waited near one wall while speaking quietly to a clerk, the child watching Peter pass with the solemn curiosity children reserved for other children in hospitals.
The smell of disinfectant and boiled linen followed them towards the entrance, thinning as colder air entered whenever the outer doors opened. With it came fragments of Chicago: the bell of a streetcar, the clatter of a wagon, a newsboy calling something Nathan could not make out and the gust of a city breeze carrying coal smoke through the doorway before the doors closed again.
Peter stopped several feet short of them.
Nathan, whose attention had wandered briefly towards the street visible through the glass, nearly walked into him.
"What is it?" he asked, looking down.
Peter turned around, and the confidence that had carried him along the corridor seemed suddenly to have deserted him. He rubbed the edge of one shoe against the floor, looked towards his mother and then down again.
"Do I have to come back?" he asked.
"Not if you can possibly help it," Nathan replied, and Peter's head came up quickly enough that Nathan smiled. "Hospitals are useful places, Peter. That doesn't mean you should make a habit of visiting them."
"I meant to see you."
Nathan's smile changed.
Mrs Halpern looked towards the doors and pretended to become interested in the street outside, granting them what privacy she could in the middle of a hospital corridor where orderlies, patients and nurses continued passing in both directions.
Nathan lowered himself onto one knee.
It brought him almost level with Peter, and for once there was no chart between them, no thermometer waiting to be read, no stethoscope hanging around Nathan's neck and no fever making the boy too tired to keep his eyes open. Peter simply stood there in his coat, pale but upright, ready to go home.
"You listen to me, Peter Halpern," Nathan said, placing one hand gently upon his shoulder. "You're a strong, smart young man. Stronger than you realise, I suspect, although I would appreciate it if you didn't use that statement as an excuse to frighten your mother."
Peter smiled.
Nathan's thumb moved once against the shoulder of the coat before he continued. "You've spent three days surrounded by strangers poking you, listening to you breathe, asking ridiculous questions and telling you when you're allowed to sleep, and somehow you've remained almost tolerable throughout the experience."
"Almost?" Peter asked, the smile widening into a grin.
"Let's not become arrogant."
Mrs Halpern laughed quietly behind them.
Nathan looked at Peter for another moment, and the humour softened without disappearing altogether. "I expect great things from you," he said. "I don't particularly care what sort. You don't have to become a doctor or a professor, and you certainly don't need your name printed in newspapers. You might become a teacher, build bridges, open a shop, write books or decide upon something neither of us has thought of yet. Whatever you choose, I expect to hear one day that Peter Halpern has accomplished something extraordinary."
Peter considered this with the seriousness only a child could bring to the practical difficulty in an adult's promise. "How would you hear?"
Nathan pretended to think about it. "I have people."
Peter laughed. "So does my mother."
"Then between the two of us there will be nowhere for you to hide," Nathan replied, glancing towards Mrs Halpern as she shook her head.
Peter's amusement lasted a few seconds longer before fading into something more thoughtful. He studied Nathan's face with the peculiar directness children possessed before adulthood taught them to disguise curiosity.
"What if I don't do anything extraordinary?" he asked.
Nathan answered without hesitation.
"Then live well," he said, and Peter became still beneath his hand. "Be kind when you can. Learn as much as you can. Help somebody when you're able to help them. Find people worth loving and make certain they know it. If you manage those things, I think you'll discover you've accomplished considerably more than most people who spend their lives trying to become extraordinary."
Peter did not answer immediately.
Behind him, the outer doors opened and a man carrying a parcel entered, bringing a brief wash of street noise and cool air into the corridor. A nurse hurried past Nathan with a sheaf of papers, and somewhere behind the reception desk somebody laughed at something before remembering where they were and lowering their voice.
For a moment Nathan wondered whether he had said too much to an eight-year-old.
Then Peter stepped forward and wrapped both arms around his neck.
Nathan froze.
The gesture was so ordinary that nobody farther down the corridor paid it any attention. There was no grand declaration and no sudden silence around them. An eight-year-old boy simply hugged the physician kneeling in front of him and held on.
Nathan's hand, which had been resting against Peter's shoulder, remained awkwardly suspended behind the boy for a second before settling against his back.
Very gently.
"Thank you," Peter whispered against his shoulder.
Nathan closed his eyes for only a moment, aware of Mrs Halpern standing nearby and the hospital continuing around them as though nothing important had happened.
"You're welcome," he replied, moving his hand once between Peter's shoulders before the boy released him.
When Nathan stood, Mrs Halpern was looking at him differently.
There were tears in her eyes, though she had enough composure not to let them become anything more. She took Peter's hand before turning fully towards Nathan, and when she spoke the gratitude in her voice was earnest enough that Nathan instinctively searched for some piece of humour with which to escape it.
"Professor Drake, I don't know how to thank you."
"You don't need to," Nathan replied.
"I do," Mrs Halpern insisted, and the quiet firmness of the answer stopped the joke before Nathan could find one. She looked down at Peter, her fingers tightening around his, and when she raised her eyes again there was something older than the last three days in them. "When we came here, I thought—"
She stopped.
Nathan knew what she had thought.
She had already watched one son become sick, had already sat beside a hospital bed while physicians failed to reverse what was happening and eventually gone home without him. When Peter's fever rose and his breathing worsened, she had not arrived carrying only the fear of influenza. She had arrived carrying the memory of another bedside, and Nathan would not make her describe it merely because unfinished sentences made other people uncomfortable.
"Take him home," he said softly, glancing towards Peter before meeting her eyes again. "That's thanks enough."
Mrs Halpern pressed her lips together and nodded. "I will."
"And make him rest."
"I will."
"Traitor," Peter muttered towards Nathan, looking genuinely wounded by the alliance.
"You'll understand when you're older," Nathan replied, reaching down to straighten the boy's collar.
"That's what my mother says."
"Your mother is obviously an intelligent woman."
"Thank you, Professor," Mrs Halpern said, laughing despite herself.
Peter began pulling impatiently towards the doors, and his mother allowed herself to be led after giving Nathan one final look. The outer door opened and admitted pale morning light along with the sound of wheels, hooves and a streetcar bell somewhere beyond the hospital steps.
"Goodbye, Professor Drake," Peter called, turning at the threshold and lifting one hand while his mother held the other.
"Goodbye, Peter," Nathan replied, returning the gesture. "Try not to acquire anything else interesting."
Peter's laughter followed him through the door.
Nathan remained where he was.
Through the glass he watched Mrs Halpern guide her son down the steps. Peter objected when she took his arm, then discovered on the first step that descending was considerably different from walking along a flat corridor and accepted the assistance with less argument than Nathan expected. His mother said something Nathan could not hear. Peter looked up at her, answered, and together they reached the pavement.
For several seconds they remained visible among the movement of the street, Mrs Halpern keeping herself between Peter and the traffic while he tried to look everywhere at once after three days indoors. Then a wagon passed between them and the hospital, pedestrians crossed Nathan's view, and by the time the street cleared again the Halperns had disappeared into Chicago.
Peter was going home.
Nathan stood at the doors for a little while after there was nothing left to watch.
He had saved people before. Soldiers, researchers, strangers, men whose names he had never learned and others whose names he remembered far too clearly. Sometimes he had done it openly with medicine, sometimes secretly with Red-Light, and sometimes through means that left the person concerned with no idea there had ever been anything from which they required saving. He had pulled men away from death under circumstances far more dramatic than an influenza ward in Chicago, yet there was something about watching Peter disappear into an ordinary street with his mother's hand around his arm that settled more deeply than Nathan expected.
Perhaps it was because Peter had hugged him.
Nathan considered that possibility for all of two seconds before deciding he had absolutely no interest in examining it further and turned back towards the hospital.
The coughing found him almost immediately.
It had never stopped. The entrance and the sounds of the street had merely hidden it for a while, and as Nathan walked deeper into the building it returned in layers: one dry cough from behind a partition, another deeper and productive farther along, then a prolonged fit accompanied by the scrape of a chair and a nurse telling somebody to breathe slowly. Beneath those sounds came footsteps, wheels, murmured instructions and glass touching metal, the ordinary machinery of a hospital trying to continue functioning while more sick people arrived than anyone was comfortable acknowledging.
Peter was going home.
Others were not.
The warmth left Nathan's expression by degrees as he walked, and by the time he returned to the ward Professor Drake had settled back into place.
Whitaker intercepted him before he reached the central table, coming towards him with a folded message in one hand and his spectacles sitting at their customary slight angle. He looked as though he had been waiting long enough to become impatient but not long enough to admit it.
"Drake, I've been looking for you," he said, holding out the paper.
"You found me," Nathan replied as he accepted it. "Remarkable work."
"You may reconsider the joke after you read that," Whitaker said, folding his arms while Nathan opened the message.
It was brief enough to read in seconds.
Nathan read it once, then again more slowly, the humour leaving his face before he reached the final line.
"Where?" he asked.
"Another hospital nearby," Whitaker replied, lowering his voice when a nurse passed behind Nathan carrying a tray of medicines. "They lost one of the respiratory cases early this morning. Rapid deterioration. Pneumonia, or what they were calling pneumonia. LeCount is examining him today."
Nathan looked up. "They agreed to let me attend?"
"I spoke with one of their physicians yesterday after you started asking everyone in Chicago for records. Apparently your reputation crossed the Atlantic before you did."
"How unfortunate."
"He knows your pathology work."
"Less unfortunate," Nathan replied, folding the message.
Whitaker's mouth twitched. "They're willing to let you observe."
"How long ago did the patient die?"
"Early this morning."
"Clinical course?"
"Short. Fever, cough, increasing respiratory difficulty, then a very rapid decline."
Nathan slipped the note into his coat and reached for the medical case he had left beside the desk. The movement was unhurried, but Whitaker had spent enough time with him over the last three days to recognise when Nathan had already made a decision.
"Take me there," Nathan said.
The other hospital was close enough that finding a motorcar would probably have taken longer than walking, so they went on foot. Chicago had properly awakened by then, and after the enclosed warmth of the ward the city struck Nathan with its size and noise all over again. Streetcars clattered along steel rails, bells sounding impatiently as wagons and motorcars competed for the same intersections. Delivery boys threaded between pedestrians carrying parcels beneath their arms, shopkeepers stood in doorways, and smoke hung above the roofs in a dirty veil that softened the daylight without managing to cool it. Every few blocks the smell changed: coal smoke gave way to horses, then bread from an open bakery, damp stone where someone had thrown water across a pavement, oil and hot machinery drifting through the doors of a workshop.
Whitaker said little, and Nathan was grateful for it.
He carried his medical case in one hand while keeping the other inside his coat pocket, his mind already several streets ahead. He had seen death from respiratory disease before, more than enough of it, and the prospect of another dead man did not draw him through Chicago out of morbid curiosity. A living patient showed a physician how a disease behaved while the body was still resisting it. A dead one, unpleasantly but often more clearly, could show precisely where that resistance had failed.
The hospital receiving them was smaller than the one Nathan had spent the previous three days inhabiting. Its entrance hall was narrower and darker, with worn stone near the doors and a reception desk that appeared too small for the number of people trying to use it. An attendant met them after Whitaker gave their names and led them away from the public rooms, down a staircase and through a pair of heavy doors.
With each flight the sounds above became duller.
The air grew cooler.
The smell changed with it.
Disinfectant remained, but beneath it lay preservative chemicals, damp masonry, metal and the faint unmistakable odour that no amount of scrubbing entirely removed from rooms built for the dead.
Their footsteps sounded differently against the lower floor.
Several physicians had already gathered in the postmortem room. White aprons covered dark clothes, sleeves had been rolled above wrists, and instruments were arranged on a nearby surface beneath the hard electric light. A younger physician stood near one wall with a notebook held in both hands and the concentrated expression of a man determined to record everything correctly. Two older doctors spoke quietly near a basin, one drying his hands while the other reread a page of notes.
At the centre of them stood Edwin R. LeCount.
Nathan knew the name before he knew the man. LeCount had the manner of someone accustomed to rooms becoming quiet when he began speaking, but there was none of the theatricality Nathan had occasionally encountered in physicians who enjoyed an audience too much. His attention remained primarily on the covered body and the papers beside it rather than the men gathered to watch him.
Whitaker brought Nathan forward.
"Professor Nathan Drake," he said, and Nathan set his case aside before offering his hand.
"Drake," LeCount replied as he shook it. "London?"
"University College originally."
"I know some of your work."
"Then I apologise in advance."
The corner of LeCount's mouth moved. "You've been looking at the respiratory cases."
"For three days."
"And?"
Nathan glanced towards the covered figure on the table. "I'd rather answer after you've shown me what killed him."
The trace of amusement disappeared from LeCount's expression.
"Fair enough."
Nathan removed his coat, rolled his sleeves and accepted an apron before washing at the basin. He scrubbed methodically while conversation continued behind him, dried his hands and joined the others around the table.
Only then did he look properly at the dead man.
Young.
That registered before anything else.
Not elderly, not visibly wasted by chronic disease, not the sort of patient whose death from pneumonia could be accepted with the melancholy explanation that the body had already been failing. He looked like one of the thousands of men Nathan and Whitaker had passed in the street twenty minutes earlier, someone who ought to have been going to work rather than lying beneath an electric lamp in a basement room.
Cyanosis remained evident around his face.
Nathan had seen the same colour beginning in living patients.
LeCount started to summarise the clinical history, but Nathan found himself looking again at the man's face. Something about the discussion bothered him before it had properly begun, and when he understood what it was he interrupted before LeCount could move much farther.
"Doctor," Nathan said.
LeCount looked up from the notes. "Yes?"
Nathan glanced towards the body. "What was his name?"
For several seconds nobody answered him.
The silence was not callous so much as revealing. Since Nathan entered the room the dead man had been the patient, the deceased, the case and, in the written material, little more than an age attached to a clinical course.
"His name?" LeCount repeated, one hand resting near the edge of the table.
"Yes," Nathan replied, looking around the gathered physicians. "A man on a table should have one. Otherwise, sooner or later, we begin discussing an object. He wasn't one."
There was no accusation in his voice. Nathan understood the distance physicians needed in rooms like this. He had used the same language thousands of times himself because a doctor could not carry the full emotional weight of every patient into every incision, every report and every death without eventually becoming useless beneath it.
Distance was necessary.
Erasure was something else.
The younger physician crossed to the side desk and began sorting through the admission papers while everyone else waited. Paper whispered beneath his fingers, and somewhere at the basin a tap had not been fully closed, water falling at slow intervals into the porcelain.
"Daniel Walsh," the younger man said at last, finding the relevant sheet and reading farther down it. "Twenty-seven years old."
Nathan nodded once. "Daniel Walsh."
The body did not change, but the room did for Nathan.
Twenty-seven years old. Young enough that there should have been decades between this table and the ordinary end of his life. Nathan knew nothing yet of whether he had been married, whether his parents lived, whether he had brothers or sisters, what he had eaten on his final ordinary morning or what minor irritation had occupied him before fever made all of it irrelevant. A name could not restore those things, but it prevented the man from disappearing entirely beneath the pathology.
"I'm sorry, Daniel," Nathan murmured, softly enough that perhaps only LeCount heard him.
Then he straightened, and whatever sadness had entered his expression settled behind the clinical concentration returning to his eyes.
LeCount consulted the record again. "Daniel Walsh, twenty-seven years of age. Reported in good health before the present illness. Acute onset of fever, headache, general muscular pain and weakness, followed by cough."
Nathan listened without interrupting.
Nothing in those first symptoms demanded alarm. Fever, headache, aching muscles, exhaustion and cough belonged comfortably enough beneath the diagnosis already being used around Chicago. Nathan had heard nearly identical descriptions in France and had spent the last three days hearing them again here.
It was the progression that mattered.
"Respiratory difficulty increased rapidly," LeCount continued, turning the page slightly beneath the light. "The cough became productive. Cyanosis became pronounced. His condition deteriorated despite treatment."
"How long from the first recognised symptoms to serious respiratory involvement?" Nathan asked, keeping his gaze upon Daniel rather than the notes.
"Less than three days," one of the attending physicians answered from across the table. "He continued working through part of the first."
"What did he do?"
"Freight clerk."
"Heavy labour?"
"No. Manifests, records, loading accounts. Some movement through the yard, but mostly clerical."
Nathan nodded and said nothing further.
Another healthy young adult who had gone from ordinary work to death in the space of days.
LeCount placed the clinical history aside. "Let's see what we have."
The room quietened.
Nathan had attended more postmortem examinations than he could easily count. The instruments possessed no novelty for him, nor did the necessary incisions or the peculiar stillness of a body from which everything physicians ordinarily watched had departed. He had never believed respect for the dead meant refusing to look at them. If Daniel Walsh had died from something they did not understand, then the final service medicine could offer him was to look carefully enough that the next person might not.
The external examination gave them little reason to suspect chronic disease. Daniel had the build of a reasonably healthy young man, without the wasting Nathan associated with longstanding illness, though the colour remaining around his face and extremities immediately recalled what the physicians had described before death.
Then the thoracic cavity was opened.
The change among the physicians was almost imperceptible. One leaned closer, the younger man with the notebook stopped writing for perhaps a second, and another physician drew a slower breath. LeCount himself paused.
Nathan saw why.
The lungs were wrong.
The thought arrived before any more sophisticated description could replace it. They were too heavy in appearance, too dark and congested, their surfaces mottled with areas of haemorrhage visible even before the organs had been removed for closer examination. Nothing about them suggested the light, resilient structure upon which ordinary respiration depended.
Nathan moved half a step nearer.
Then he noticed the wetness.
There was too much fluid.
Not merely the moisture expected in living tissue, nor anything he was prepared to dismiss as a consequence of death. The lungs looked sodden, swollen and heavy with something that should never have occupied them in such quantity.
LeCount carefully lifted one.
Its weight confirmed what appearance had suggested.
"Heavy," one of the physicians murmured, his clinical detachment briefly giving way to surprise.
"Very," LeCount replied, turning the organ beneath the light.
Nathan's gaze moved methodically across the surface, following areas of congestion into patches of haemorrhage. Some were comparatively small, irregular dark-red islands beneath the surface, while others spread far enough that Nathan could no longer think of them as incidental bleeding accompanying an otherwise ordinary pneumonia.
LeCount palpated the tissue carefully.
The lung responded badly beneath his fingers, too dense in places and too yielding in others, and through all of it there remained that same impression of wetness.
Nathan had seen pulmonary oedema before. He had watched fluid fill lungs after injury, infection, cardiac failure and toxic insult. He knew what happened when an organ built to contain air instead accumulated liquid, and he knew the increasingly desperate physiology that followed.
Yet the speed of Daniel Walsh's illness made what lay before him profoundly uncomfortable.
LeCount positioned the lung for sectioning.
The blade passed through the tissue.
Fluid welled across the cut surface almost immediately.
Nathan leaned forward.
A thin reddish liquid gathered along the fresh section and began running downward, blood mingling with oedematous fluid until the distinction between haemorrhage and saturation seemed almost academic.
The younger physician stopped writing again.
"Good God," somebody said quietly.
LeCount did not answer.
Nathan's face became very still.
He had seen this already, not exposed beneath a dissecting-room lamp, but in what it produced. He remembered the young labourer bent over a basin while pink froth escaped his mouth, the wet bubbling respiration audible from several beds away and the skin beginning to darken because lungs that continued moving could no longer exchange enough oxygen to sustain the body they belonged to.
Nathan had seen the symptom.
Daniel Walsh was showing him its source.
"Another section," Nathan said quietly, his gaze never leaving the exposed tissue, and when LeCount looked towards him he indicated a different region. "There, please."
LeCount nodded and made the cut.
Again the lung released fluid, not a trace or an ambiguous dampness but enough reddish liquid to well visibly from the tissue while blood marked the haemorrhagic regions.
"That shouldn't be there," the younger physician said, staring at the section.
"No," Nathan replied, so quietly the word was almost lost beneath the movement around the table. "No, it should not."
One of the older physicians adjusted his spectacles and moved closer. "Acute oedema."
"Certainly," LeCount replied.
"And haemorrhage."
"Extensive haemorrhage," Nathan said, indicating another portion of the cut surface. "Look there."
They followed his gesture.
The bleeding was not confined to one convenient focus. Multiple areas of pulmonary tissue showed blood where air should have been, with haemorrhage distributed through tissue already swollen with fluid.
Nathan looked towards Daniel's face.
Twenty-seven years old, ill for scarcely three days.
His charts seemed to unfold inside his memory: the nineteen-year-old, the twenty-two-year-old, the twenty-four-year-old, the twenty-six-year-old, the twenty-eight-year-old, the thirty-one-year-old and the thirty-five-year-old. He remembered the twenty-nine-year-old labourer producing pink froth, the twenty-four-year-old whose fever had begun scarcely a day before respiratory distress followed, and then Peter, eight years old, probably sitting somewhere beside his mother at that very moment while Chicago moved around them.
"What are you thinking?" LeCount asked, watching Nathan rather than the specimen.
Nathan remained silent for several seconds. France returned first, not as faces or places but as reports, observations and clinical fragments that had bothered him enough to cross an ocean carrying copies of them. The reports from Kansas followed, then the Chicago ward he had just left, and finally his attention returned to the wet lung in front of him.
"The lung is drowning," Nathan said, and when one of the physicians looked sharply towards him he gestured to the sectioned tissue before the phrase could be mistaken for literalism. "Functionally. The spaces meant to contain air are filling with fluid and blood. Whatever else is happening here, respiration is being physically displaced. Even before consolidation accounts for all of the failure, you're replacing air with something through which useful gas exchange cannot occur."
"And quickly," LeCount said.
Nathan looked towards him. "That's what troubles me."
"Severe pneumonia can kill quickly," another physician observed.
"Yes," Nathan replied without argument. "It can produce consolidation, oedema, haemorrhage and respiratory failure. Nothing we're looking at is impossible by itself." He paused, his gaze moving from the physician back to the lung. "It's the arrangement that bothers me. His age, the speed, the amount of haemorrhage, the amount of fluid, the cyanosis before death and the deterioration. I can explain every one separately without doing violence to ordinary pathology. Put them together and I become considerably less comfortable."
"Influenza followed by pneumonia?" the physician suggested.
"Possibly," Nathan replied, watching LeCount continue the examination.
"Primary pneumonia?"
"Possibly."
"Something else?"
Nathan looked towards him. "Possibly."
The physician's expression tightened. "You're rather fond of that word."
"I'm fond of not lying," Nathan replied, and the irritation disappeared from the exchange.
LeCount continued.
The airways themselves offered little reassurance. The inflammatory process had travelled deeply through the respiratory tract, with congestion and secretions occupying passages that should have remained open. Nathan followed the examination with growing concentration as the trachea gave way to the bronchi and the bronchi towards the deeper structures of the lung.
The disease had gone down.
He caught himself thinking of it almost as an assault and rejected the idea. Diseases did not assault. Organisms did not hate Daniel Walsh, did not possess military strategy and did not understand what they destroyed. Nathan had spent too long studying living systems to indulge that sort of easy anthropomorphism.
Yet damage could have direction without purpose. Infection could begin in one place and find another more useful. Airway gave way to bronchiole, bronchiole to lung and lung to the air spaces upon which Daniel's life depended, and with every step deeper the distance between being sick and being unable to breathe had narrowed.
LeCount paused over another haemorrhagic region. "I've seen lungs bleed," he said, his voice lower than before.
"So have I," Nathan replied.
LeCount continued looking down at the organ. "Not like this."
Nathan shook his head slightly. "No. Neither have I."
Measurements followed and observations were dictated. Tissue was selected for microscopic examination, and when the younger physician prepared to take a specimen from one of the most visibly damaged regions, Nathan stopped him with a small gesture.
"Take that, certainly, but take another from there," Nathan said, indicating an area that appeared comparatively preserved. "And another from the margin between them."
The younger physician looked towards LeCount.
LeCount nodded. "Do it."
"Why the preserved tissue?" Whitaker asked from beside Nathan.
"Because if we examine only the most spectacular destruction, we'll learn what the disease looks like at the end," Nathan replied, watching the specimens being separated. "I want the road that brought it there."
Whitaker nodded slowly.
Nathan's gaze returned to the tissue.
He could have learned more in seconds.
That possibility sat quietly beneath every ordinary observation. A microscopic extension of Red-Light placed against Daniel's damaged lung could read the tissue in ways no microscope in the building could approach. Nathan could compare what remained there against the living viral material already isolated within himself, trace the destruction at a cellular level and perhaps answer questions these physicians would require months or years to approach.
He did nothing.
Not yet.
There were too many eyes, but secrecy was not the only reason. Nathan wanted to know what ordinary medicine could see first, because that distinction mattered. The advantages Red-Light gave him were extraordinary enough to become dangerous if he allowed them to replace scientific discipline. Knowledge obtained effortlessly could make a man careless about proving what he knew, and Nathan had spent too many years demanding independent verification from everyone beneath him to grant himself exemption simply because his most sophisticated laboratory happened to extend through his own body.
"What do you expect under the microscope?" Whitaker asked.
Nathan considered the question while LeCount examined another portion of the lung. "Damage," he replied, and when Whitaker turned towards him with an unimpressed expression Nathan's mouth moved faintly. "Forgive me. That wasn't especially useful."
"Not particularly."
"Inflammatory infiltration, fluid in the air spaces, blood where it shouldn't be, damage to the respiratory surfaces and perhaps fibrinous material," Nathan continued. "Beyond that, I'd rather see it before deciding what ought to be there."
That answer appeared to satisfy LeCount more than speculation would have.
The examination continued, and with another cut came more fluid. Nathan watched it gather along the section, disturbed by the haemorrhage but even more by the sheer wetness of the tissue. Daniel's lungs seemed almost saturated, the architecture designed to hold air progressively surrendered to liquid until every breath must have demanded more work for less return.
Nathan imagined the final hours despite himself: Daniel breathing faster because each breath provided less, his heart accelerating in compensation, the sensation of insufficient air becoming impossible to ignore while the lungs grew wetter and blood entered damaged spaces. Breathing would have become labour rather than reflex, then exhausting labour, and finally something his body could no longer sustain.
Nathan stopped himself.
Daniel Walsh was not a mechanism.
That was precisely why he had asked for his name.
"What did he say?" Nathan asked suddenly.
The attending physician looked towards him. "Who?"
"Daniel. While he could still speak."
The physician's expression changed slightly as he thought back. "Mostly that he couldn't breathe."
Nathan's jaw tightened. "Anything else?"
"He asked for water. And he asked us to tell his sister where he was."
Nathan looked towards him. "Sister?"
"Anna. It's on the admission sheet."
Nathan looked down at Daniel again, and the facts rearranged themselves into something more human. Daniel Walsh, twenty-seven years old, freight clerk, a sister named Anna who presumably still expected somebody to tell her what had happened.
There was the man again.
A little more of him rescued from beneath the clinical record.
LeCount watched Nathan for a moment before returning to the lungs. "They're full of haemorrhage," he said quietly.
Nathan looked towards the exposed tissue. "Yes."
Neither man spoke for several seconds while the younger physician wrote and somebody at the basin began washing an instrument.
"We don't know what we have," Nathan said eventually.
"No," LeCount replied.
Nathan found the admission strangely reassuring. It meant LeCount had not become so attached to the familiar labels available to him that he would force the pathology beneath one prematurely.
One of the older physicians suggested cultures.
"Absolutely," Nathan said, turning towards him. "Lung tissue, bronchi and whatever else Doctor LeCount considers appropriate. We need to establish whether bacteria are participating."
"Participating?" Whitaker repeated.
"Don't assume one organism merely because one diagnosis appears likely," Nathan replied. "If influenza injured the respiratory tract first, another organism may have exploited the damage afterwards."
"Secondary infection."
"Potentially."
"And if the cultures show nothing?"
"Then we've learned something."
LeCount glanced towards Nathan. "You want tissue retained."
"Yes."
"How much?"
"As much as you can reasonably preserve without compromising your examination."
"For comparison?"
"Chicago against Chicago first. If another patient dies after the same clinical progression, compare them. If these findings repeat—"
Nathan stopped.
The sentence had been scientifically sound.
He hated it anyway.
For the comparison he wanted, another person had to die.
He looked towards Daniel.
"If another patient dies," he corrected quietly, "then we compare them."
LeCount understood the distinction. "Agreed."
"And I'd like copies of everything. Clinical history, temperatures, respiratory observations, gross findings, microscopic findings when they're ready, cultures. Everything."
"You really are going to Kansas," Whitaker said.
Nathan glanced towards him. "Yes."
"When?"
"Soon."
"How soon?"
Nathan looked at Daniel Walsh's lungs, and the answer that had been vague when he entered the room became firmer as he looked at them.
"Tomorrow."
Whitaker's eyebrows rose. "You said another day or two."
" I said that yesterday. Peter is home"
"And the others?"
"You'll continue sending records. There is more I can learn in Chicago, but Kansas matters more now."
LeCount looked towards Nathan. "Why Kansas?"
"Because men there became ill in numbers large enough to attract attention before Chicago gave me Daniel Walsh."
The use of Daniel's name seemed to settle over the room differently than the deceased would have done.
Nathan was glad.
"Camp Funston," one physician said.
Nathan nodded. "If this is connected, I want the beginning while the people involved still remember it clearly. Who became sick first, where they slept, where they worked, how quickly it spread, what happened to the severe cases and whether anyone died with lungs resembling these."
"And France?" LeCount asked.
Nathan looked towards him. "France is why I'm here."
That changed the room.
"You've seen this there?" LeCount asked.
"I've seen enough pieces that I'm no longer willing to assume they're unrelated without investigating them."
"The same lungs?"
"I didn't attend an examination like this there."
"Clinical resemblance?"
"Enough."
LeCount looked back towards Daniel. "Then this may be larger than Chicago."
"It may be," Nathan replied, and stopped there.
He would not turn one autopsy into an epidemic, nor would he turn three locations into a chain simply because a chain would make an elegant explanation. But the thought had already formed, and once formed it was difficult to ignore. France, Kansas and Chicago were not isolated points on a page when railways joined cities, troop trains joined camps and ships joined continents. Millions of men were being transported around the world with an efficiency no previous war could have achieved, carrying letters, uniforms, bacteria, viruses and every other invisible passenger human movement had always carried with it.
An organism required no strategy if human beings supplied the transport themselves.
Nathan looked again at the lung.
"Photograph it," he said.
LeCount nodded. "We will."
"Before it's altered any further. The whole lung and the sectioned surfaces."
"Agreed."
Nathan's gaze settled once more upon the reddish fluid glistening along the cut tissue. Air should have occupied those spaces. Instead there was water, blood and inflammatory material, the physical record of Daniel Walsh's final inability to breathe.
For one brief moment Nathan thought of Peter stepping through the hospital doors with his mother's hand waiting near his arm. Peter Halpern, eight years old and going home, and Daniel Walsh, twenty-seven years old and lying open beneath a dissecting-room lamp, both caught in what Nathan increasingly suspected was the same disease and yet arriving at opposite ends of it.
The difference had to contain information.
It might lie in the host, in dose, timing, secondary infection, chance or something intrinsic to the organism itself. More likely, Nathan thought, several of those things had acted together. Biology rarely possessed the decency to provide one answer when half a dozen could cooperate.
He refused to choose before the evidence chose for him.
The examination continued for another twenty minutes, though the room gradually loosened around its edges as the most urgent observations were completed. LeCount remained near Daniel while the younger physician read back measurements and corrected one figure he had copied incorrectly. Two of the attending physicians moved towards the side of the room to compare notes, and Whitaker joined them after being called over to look at something on the clinical chart. Instruments were carried to the basin, water ran, and somebody opened the door briefly to speak to an attendant in the corridor before closing it again.
Nathan remained beside LeCount.
He asked two questions concerning the distribution of the haemorrhage, listened while the younger physician read back the description of the second lung and suggested that the photographs include a scale beside the sectioned surface. He did not look repeatedly towards the specimens selected for preservation. He did not move towards them the moment LeCount's attention shifted.
He waited.
Patience had become instinctive after years of hiding Red-Light beneath ordinary human behaviour. Secrecy rarely depended upon elaborate deception. Most of the time it depended upon behaving exactly as everyone expected until they became interested in something else.
Eventually they did.
LeCount crossed towards Whitaker when one of the physicians called his name. The younger doctor carried a labelled container to another bench and turned his back while arranging several others. At the far end of the room somebody began complaining quietly about the condition of one of the lamps, tapping the metal shade with a finger while another physician advised him that striking electrical equipment was unlikely to improve it.
Nathan moved.
A portion of Daniel's lung rested in a shallow metal dish beneath the nearer light.
Up close the tissue looked worse. The cut surface possessed a wet sheen that healthy pulmonary tissue should never have carried in anything approaching this degree, reddish fluid collecting beneath it while darker islands marked haemorrhage through the damaged structure. A small amount of blood had accumulated along one edge of the dish.
Nathan leaned over it as any pathologist might have done and rested two fingers against the rim.
One fingertip touched the moisture.
Red-Light crossed the distance invisibly.
There was no tendril, no alteration in colour and no distortion of Nathan's skin. The amount he released was microscopic, little more than a living film passing between his fingertip and the moisture along the edge of the specimen. It entered Daniel's tissue, gathered what Nathan required and withdrew almost immediately, carrying so little material with it that no eye in the room could have detected anything missing.
Cells, fluid and damaged pulmonary tissue entered Nathan with it, and among them was the thing he wanted.
He drew his hand away and continued looking at the dish.
Red-Light enclosed the sample before it had travelled the length of his finger.
Nothing about the room changed. LeCount continued speaking somewhere behind him, Whitaker interrupted with a question, the younger physician's pencil scratched rapidly enough across paper that the nib caught once and made him mutter beneath his breath, and at the basin somebody turned off the water after allowing it to run far longer than necessary. Somewhere beyond the tiled walls a trolley rolled along the corridor.
Nathan became still in the middle of all that ordinary activity while another world opened inside him.
Peter's sample remained isolated.
Nathan had preserved it deliberately rather than allowing Red-Light to digest it as foreign biological material, maintaining the viral population in a minute controlled environment separated from the rest of himself. During the previous days he had studied it when he was alone, allowed carefully restricted living cells to encounter it, watched its attempts at attachment and replication and mapped enough of its behaviour that the organism was no longer entirely unfamiliar.
Now he created another compartment beside the first.
The two never touched.
They could not.
Living barriers separated them more completely than glass ever could, and Nathan maintained another layer between both samples and the rest of Red-Light so that his own adaptive biology could not contaminate what he was trying to observe.
On one side remained the infection taken from Peter Halpern.
On the other, the infection taken from Daniel Walsh's ruined lung.
Nathan compared them.
The first answer came quickly enough that he distrusted it.
He checked again.
Then a third time, varying what he examined and refusing to let the ease of recognition become certainty merely because certainty was convenient.
The result did not change.
Whatever had infected Peter and whatever had killed Daniel belonged to the same influenza lineage. Their underlying biological architecture matched closely enough that Nathan could dismiss the possibility of two unrelated respiratory diseases producing superficially similar symptoms. Daniel had not died from some separate infection that happened to imitate what Nathan had been studying in Peter.
The connection was real.
What troubled Nathan was that the samples were not identical.
Variation itself meant very little. Nathan expected it. No biological population reproduced with perfect fidelity, least of all one multiplying at the pace this organism appeared capable of maintaining. Had the differences been scattered without consequence, he would have noted them and moved on.
They were not.
Nathan allowed Peter's sample access to a carefully prepared population of human respiratory cells formed within the sealed compartment. He watched the virus encounter the cellular surface, watched some particles fail and others recognise structures they could exploit, attach and gain entry. Replication followed, then the first beginnings of the cellular response.
He ended the trial and repeated it.
Then he did the same with Daniel's sample.
Nathan's expression altered so slightly that nobody across the room would have noticed.
Daniel's population attached more efficiently.
Not every particle. Not every cell. Nothing about the difference resembled the absolute change a less careful observer might have wanted to find. Some of Daniel's viral particles failed exactly as Peter's did, and some of Peter's succeeded perfectly well.
But across repeated trials a greater proportion of Daniel's population found purchase upon human respiratory cells, and among those successful variants some established themselves with an efficiency Nathan had not observed in Peter's sample.
He changed the cells.
The difference remained.
He altered the conditions.
Again.
Still there.
Nathan rested one hand against the edge of the workbench while the implications began arranging themselves in his mind.
Mutation was the obvious explanation, although he refused to grant the word more certainty than the evidence deserved. Influenza changed whenever it reproduced; there was nothing remarkable in that by itself, because replication was imperfect and imperfect replication produced variation. Nathan had spent too many years manipulating organisms not to understand the principle intimately. What troubled him was not simply that Daniel's sample differed from Peter's, but that several of those differences appeared to favour the same outcome.
The virus recovered from Daniel's lungs was better, at least in part, at gaining entry to human respiratory cells.
Nathan looked towards Daniel's body.
"No," he murmured, too softly for anyone else to hear.
He returned his attention inward.
Attachment was only the beginning.
Nathan could not simply turn Red-Light's own defences loose upon the samples and call the result meaningful. His biology was not an ordinary human immune system, and the speed with which it could analyse and destroy a foreign organism would tell him almost nothing about how influenza survived in a normal patient. Instead he recreated narrower pieces of the environment an infected human cell might produce around itself, exposing both populations to comparable antiviral pressures while deliberately preventing Red-Light from doing what came naturally to it.
Peter's sample struggled.
Daniel's struggled as well.
But not quite as much.
Nathan repeated the experiment.
He adjusted the conditions and repeated it again, looking for the mistake that would allow him to dismiss what he had seen.
The mistake did not appear.
Some of Daniel's population continued functioning under conditions that inhibited Peter's more effectively. They were not invulnerable to the body's response and had not somehow escaped every mechanism a human host possessed to interfere with infection. Nathan rejected that interpretation immediately.
The difference was smaller than that.
It was also more believable.
Some variants simply endured the hostile environment a little better.
A little longer.
Enough to continue replication where another variant might fail.
Enough to leave more descendants.
Nathan ended the trial before Red-Light itself could begin adapting to the samples and ruin the comparison.
Perhaps ten seconds had passed in the room.
The young physician was still writing.
LeCount was still speaking to Whitaker.
Nathan had already found more than he wanted.
He looked towards Daniel.
Peter's infection had been dangerous. Nathan knew that better than anyone because he had watched it closely enough to decide intervention was justified. Daniel's had gone farther, not only through the lungs of the man lying on the table but, Nathan was becoming increasingly convinced, biologically as well.
The conclusion came too easily.
Nathan distrusted it for precisely that reason.
The samples had not been obtained under equivalent conditions. Peter's had come from a living child earlier in the course of illness, while Daniel's had come from the deep lung of a man dead after catastrophic respiratory failure. Selection might have occurred inside Daniel himself. The variants thriving in the deep lung might not represent what he had inhaled when he first became sick. Different tissues could favour different portions of the viral population, and Peter and Daniel might have been infected through separate chains with several unknown hosts between them.
Nathan had two patients.
That was not a trend.
It was barely the beginning of a question.
He forced himself to examine Daniel's population more carefully rather than allowing the elegance of the theory to seduce him.
Red-Light separated variants from the sample and tested them individually.
Some behaved almost exactly like Peter's.
Others did not.
The pattern emerged gradually rather than as one dramatic revelation. Certain variants attached to human respiratory cells more effectively but remained just as vulnerable once the cell's defences began working against them. Others showed little improvement in attachment yet continued replicating somewhat better under hostile conditions. A smaller fraction possessed advantages in both.
Nathan remained bent over the dish while a peculiar unease settled through him.
The virus had not completed anything.
That was what bothered him most.
Daniel had not been infected by some clean, perfected version of the organism in which every viral particle carried the same advantageous changes. His sample remained a crowd of related variants competing inside the same host. Some changes were useless. Others were almost certainly harmful to the virus itself. A few happened to make one part of infection easier, and an even smaller number combined useful traits.
The population was still sorting itself out.
There was no intention behind it, no intelligence searching deliberately for the best solution. Mutation produced possibilities and selection discarded most of them, leaving whatever happened to reproduce successfully enough to remain.
Daniel had died before the virus needed to become anything approaching perfect.
Nathan's eyes moved from the dish to the body on the central table.
That was the ugly simplicity of it.
The virus did not need perfection to kill him.
It merely needed to remain ahead of him long enough.
Nathan returned to the comparison and concentrated upon the interaction between the viral surface and the structures presented by human respiratory cells. Every cell presented structures to the world around it. Hormones recognised some, proteins bound to others, toxins exploited them and pathogens did the same. For a virus, finding the correct structure could mean the difference between brushing uselessly against a cell and gaining entry.
Peter's virus could find that structure.
Daniel's population contained variants that were becoming better at using it.
The thought sat badly with Nathan.
Worse, once entry had been achieved, some of Daniel's variants were marginally better at enduring the cellular response waiting on the other side. Not immune, not resistant in any absolute sense and certainly not unstoppable.
They did not need to be.
Evolution had never required perfection.
It required only that one variant leave more descendants than another.
Nathan withdrew his attention from the experiment and became aware again of the room around him. One of the older physicians had begun washing his hands. The troublesome lamp at the far bench flickered once and steadied. Whitaker was reading something LeCount had handed him, his spectacles pushed higher on his nose.
Nothing had changed.
That almost offended Nathan.
Daniel Walsh had died. A room full of physicians was trying to understand why. Somewhere upstairs other patients were eating lunch, complaining about medicines and asking nurses when they could go home. Outside, Chicago's streetcars still had schedules to keep.
And in the middle of that ordinary morning Nathan had watched the infection changing.
He forced himself through the alternative explanations again.
Perhaps Peter and Daniel had acquired different branches of the virus before either entered hospital. Perhaps several transmissions stood between them. Perhaps Daniel's own lungs had imposed intense selection during his brief illness, favouring variants better suited to the deep respiratory tract. Perhaps the changes Nathan saw would disappear entirely in the next host.
He did not know.
That ignorance mattered.
None of those possibilities made the observation comforting.
Nathan's thoughts moved naturally towards Kansas.
Until that moment Camp Funston had been the next sensible destination in an investigation. Now it felt necessary. A military camp offered something Chicago could not easily give him: a concentrated outbreak among men who had slept, trained, eaten and worked within a connected environment, observed by physicians who had watched the illness move through them. If any useful material survived from those earlier cases, Nathan might be able to compare it directly. If no specimens remained, the clinical records could still tell him whether the disease had behaved differently there.
From Kansas his thoughts returned to France, to the reports that had troubled him before he ever crossed the Atlantic, and then back to Chicago. He was careful not to turn those places into a chain merely because his mind wanted one. They were points, nothing more, and he did not yet know whether a line truly connected them.
But between those points ran railways, troop trains and ships crowded with men being moved in numbers the world had never attempted before. Soldiers travelled from towns to camps, from camps to ports and from ports across an ocean. Workers moved between rail yards, factories and homes. Children filled classrooms and returned to families at the end of the day.
Influenza required no intention of its own when humanity had built such an efficient transport system on its behalf.
Nathan sealed Daniel's sample beside Peter's, each population enclosed separately and isolated from the surrounding Red-Light. Only then did he allow the fingertip that had touched the dish to become entirely ordinary again.
"Professor?"
Nathan looked around.
LeCount had come over to him.
"You've been staring at that lung for some time," he said, stopping beside the bench and following Nathan's gaze towards the specimen. "Something troubling you?"
Nathan almost laughed at the inadequacy of the question, though nothing humorous reached his expression.
"The speed," he replied, stepping away from the dish.
"Of the deterioration?"
"Of everything."
LeCount looked towards Daniel's open chest before returning his attention to Nathan.
Nathan could not tell him what he had just discovered.
Not yet.
There was no microscope he could place beneath LeCount's eye and say there. No stain, culture or ordinary experiment in this room could demonstrate within minutes what Red-Light had shown him.
That frustrated Nathan more than the secrecy itself.
Evidence nobody else could reproduce was not proof.
Still, the knowledge remained.
The infection in Peter and the infection in Daniel belonged to the same lineage, but the populations were not quite the same. Daniel's contained variants that attached more efficiently to human respiratory cells and tolerated parts of the host response better than Peter's had. The process was incomplete, mixed and still changing, but it was real enough that Nathan could no longer dismiss it.
He looked down at the dead man.
"You didn't have much of a chance, did you?" he murmured.
LeCount glanced towards him but said nothing.
Nathan's gaze moved towards the lungs.
The wetness looked different now.
Before, it had been pathology. Now Nathan could see something of the biological journey that had produced it. A virus had entered Daniel Walsh and copied itself over and over, and those copies had not all been perfect. Daniel's body had fought back. Fever had risen. Infected cells had attempted to make themselves hostile to further replication. Immune defences had attacked what they recognised and tried to contain what they could.
Under that pressure the viral population had continued changing, not because it wanted to and not because it understood the man it was killing, but because replication made errors and selection preserved whatever happened to work. Most changes would mean nothing. Some would make the virus worse at surviving. A few would help, and those successful copies would make more copies.
Given enough hosts, blind selection could look disturbingly like intent.
"How many influenza cases have you personally seen in the last week?" Nathan asked, turning towards LeCount.
LeCount took a moment to follow the change in subject. "Here?"
"Anywhere you've been consulted."
"Several. I'd have to go through the records to give you an exact number."
"Please do," Nathan said, and something in his voice made Whitaker look over from the main table. "Every severe respiratory case you can find. I want ages, dates of onset, occupations, addresses if they're recorded, when the breathing difficulty began and whether anyone around them was ill first."
LeCount studied him. "You think they're connected."
"I think we need to establish whether they are."
"That's not quite the same answer."
"It's the only one I can defend."
LeCount continued watching him for another moment before Nathan looked towards the specimens again.
"If anything has been preserved from earlier patients—sputum, lung tissue, anything useful—I want to know about that too."
"Why?"
"Because Daniel may not be representative."
LeCount's eyes moved towards the body. "And if he is?"
Nathan did not answer immediately.
His mind had already moved beyond the basement room into a city of more than two million people. Railways ran from Chicago in every direction. Troop trains crossed the country. Men from Camp Funston moved elsewhere, and men from elsewhere moved into Funston. Soldiers crossed the Atlantic by the thousands, carrying letters, equipment, bacteria, viruses and every other invisible passenger human movement had always transported.
If the organism were adapting to human hosts while moving through them, then every successful transmission offered another opportunity for variation. Most mutations would accomplish nothing. Some would cripple the virus and disappear with the cell in which they arose. Others would vanish with the patient carrying them.
But a change that made attachment to human respiratory cells easier could move onward.
One that allowed replication to continue a little longer against the body's attempts to suppress it could move onward as well.
If both advantages appeared together in the same lineage, that lineage could compete more successfully against everything that lacked them.
Daniel's sample had shown Nathan no finished transformation, only a population leaning under pressure towards whatever helped it survive in human beings.
That was enough.
"If Daniel is representative," Nathan said at last, "then I need to get to Kansas."
Whitaker had moved close enough to hear him. "Tomorrow?" he asked, adjusting his spectacles.
Nathan shook his head.
Whitaker frowned. "You said tomorrow."
"I've changed my mind."
"When?"
Nathan looked towards the clock mounted high on the tiled wall, then back towards Daniel.
"As soon as I can arrange the train."
Whitaker stared at him. "What happened in the last five minutes?"
Nathan could not answer truthfully.
So he gave them the portion of the truth ordinary medicine might eventually be able to test.
"I looked at those lungs," he said, nodding towards the table, "and realised I no longer want to know only what this disease is doing."
LeCount waited.
Nathan glanced towards the preserved tissue.
"I want to know whether it's changing."
The room continued around them, but for a moment neither physician answered. The younger doctor kept writing, an instrument touched porcelain at the basin and somewhere beyond the door an attendant laughed briefly at something before remembering where he was and lowering his voice.
LeCount looked from Nathan to Daniel. "Changing in what sense?"
"I don't know yet," Nathan replied, and the honesty irritated him while remaining necessary. "Severity. Tissue preference. The speed at which pulmonary involvement develops. Perhaps nothing at all. But we're watching an illness move through a large number of people, and I don't want us to make the mistake of assuming the thing we identify today will behave exactly the same tomorrow simply because we've given it the same name."
Whitaker frowned thoughtfully. "You think the organism itself may vary between cases."
"Every organism varies. The question is whether any of that variation matters."
"And Kansas can answer that?"
"Kansas can give me an earlier point of comparison," Nathan replied. "For now, that's enough."
LeCount glanced towards the preserved tissue. "If I find earlier specimens?"
"Keep them. Label everything—patient, date, site of collection, stage of illness if you can establish it. Don't combine anything."
LeCount gave him a dry look.
Nathan raised one hand slightly. "Forgive me. Occupational anxiety."
"Apparently," LeCount replied, and the faintest hint of humour returned to his face.
Nathan went to retrieve his coat.
He slipped one arm into it before stopping.
Daniel remained on the table.
Twenty-seven years old. Freight clerk. Sister named Anna. He had asked for water and told them he could not breathe.
There was something obscene about how ordinary those final words were. Nathan had heard them before. Every physician had. A patient struggling for air possessed very few original ways to describe the experience.
Daniel's lungs had given the words a physical form Nathan doubted he would forget.
Nathan returned to the table.
LeCount did not ask why.
He looked at Daniel's face rather than the opened chest.
"I'm going to find out where this came from," Nathan said quietly, the words meant for a man who could no longer hear them.
His gaze lowered towards the ruined lungs beneath the electric light, their cut surfaces still shining with blood-stained fluid.
"And what it's becoming."
For another moment Nathan remained there while the postmortem room carried on around him. The young physician turned a page in his notebook. LeCount quietly asked for another container. Whitaker retrieved his own coat from the hook near the door. Water ran briefly at the basin and stopped.
He gathered his medical case and followed Whitaker towards the corridor, carrying Daniel Walsh's name with him and, hidden far more deeply, a microscopic piece of the thing that had killed him.
Peter had survived where Daniel had not.
There were likely many reasons for that difference, and Nathan had no intention of insulting either man by pretending he understood all of them after a single morning.
But he knew something now that he had not known when he watched Peter disappear into the Chicago crowd.
The difference was not only in the patients.
Something in the influenza was changing as well.