Chapter 1Breslau

Foreword

Roughly half the nitrogen atoms in your body arrived there through a reaction Fritz Haber worked out in a laboratory in Karlsruhe between 1907 and 1909.

That is not a figure of speech. Nitrogen is the limiting nutrient for plant growth; before Haber, the accessible supply came from Chilean bird excrement and from bacteria, and the world's population was approaching the limit of what those could feed. He found a way to take nitrogen out of the air.

On the afternoon of 22 April 1915, outside Ypres, some five thousand seven hundred and thirty cylinders holding about one hundred and sixty-eight long tons of chlorine were opened into the French line, and Fritz Haber was on the ground to watch it.

Almost every account of him is built around the gap between those two facts. Two Habers: the benefactor of humanity, and then the war criminal. A biography with a hinge in the middle.

This book argues that they were one act.

Both came out of the same laboratory, by the same method, and out of the same conviction. The method was the thing Haber was better at than anybody alive: take a reaction that works on a bench and force it to industrial scale. The conviction was one he stated all his life and never retracted — that in peacetime a scientist belongs to the world, and in war he belongs to his country.

There is a harder version of the argument and it is the reason Chapters 6 through 13 run continuously rather than splitting into a before and an after.

In August 1914 the Royal Navy closed the sea lanes and the Chilean nitrate stopped arriving, and German intelligence estimated that the army had months of propellant left. Haber and Carl Bosch converted the ammonia capacity to nitrogen compounds for munitions.

Without that conversion, the First World War ends inside a year.

So the machine that fed the world also kept the guns firing after the blockade should have silenced them. The bread and the gas extended the same war, and they came out of the same works at Oppau, and any structure that separates them has already conceded the argument.

I want to say clearly what this book does not do with that.

It does not convict him with hindsight. The German government's reading of the Hague Declaration was that a gas released from cylinders was not a projectile and was therefore not covered, and lawyers can and do argue about whether that reading was made in good faith. Haber maintained until his death that gas was the more merciful weapon and would shorten the war, and Chapter 13 puts that defense at its full strength before setting the casualty accounting beside it.

And it does not let him off. Chapter 11 is the twenty-second of April at length, slowly, from inside, because it is the hour on which the whole life turns. Everything before it is preparation and everything after it is a man defending it.

There is a chapter in this book that has to be quieter than the rest.

On the night of 1 to 2 May 1915, in the garden of their house in Dahlem, Clara Immerwahr took her husband's service pistol and shot herself in the chest. Their son Hermann, who was twelve, reached her first, and she died in his arms. Haber left for the Eastern Front the following morning.

Clara Immerwahr had taken a doctorate at Breslau in 1900, the first the university had awarded to a woman, and she had stopped doing science when she married. There had been a party at the house that evening and what was said at it is not recoverable. No note is known to survive.

Two readings circulate: the pacifist who could not live with what her husband had done at Ypres nine days earlier, and the scientist erased over fourteen years of marriage. This book names both, refuses to settle it, and does not narrate a scene that nobody wrote down.

Chapter 4 asks the reader to like that marriage before it goes, and does not foreshadow.

Three more things.

He was born in Prussian Silesia in December 1868 to a mother who died three weeks later and who was also his father's first cousin, and he was baptized a Protestant at Jena in November 1892 after failing in his father's business. Chapter 2 is about what a conversion buys in imperial Germany and what it quietly does not, and the answer arrives forty-one years later.

In April 1933 the Civil Service Law required the dismissal of Jewish employees. Haber, a decorated front-line officer, was personally exempt. His staff were not. He resigned rather than draw up the list, writing that for forty years he had chosen his collaborators by their intelligence and their character and not by their grandmothers.

He died in a hotel in Basel on 29 January 1934, at sixty-five, of heart failure, stopping to rest on his way to a laboratory in Rehovot that Chaim Weizmann had offered him.

And the last chapter belongs to his sons.

Hermann, in whose arms his mother died in the garden at Dahlem, killed himself in the United States in 1946.

Lutz, the son of the second marriage, became an economic historian and in 1986 published The Poisonous Cloud, the standard scholarly history of the gas war his father invented, written in a flat professional voice from beginning to end.

The account does not balance. Half the nitrogen in a living human body passed through his reaction, and this book keeps that on the table the whole way through while it counts the dead.

Chapter 1 · Breslau

The life begins with a date and a subtraction. Fritz Jakob Haber was born on December 9, 1868, in Breslau, a Prussian city in Silesia, into a Jewish family in the merchant trade. Three weeks after the birth his mother was dead. Those two entries arrive in the record already fused, and no account of the man has ever been able to separate them, because there is nothing in between them to separate: no interval of ordinary family life, no first months to be remembered wrongly and fondly later, nothing but a birth and, immediately behind it, a death that the birth had caused. Everything a biography usually has to work with at this point — the mother's temperament, the name she used for the child, what she wanted him to be — is absent, and it is absent permanently. What survives is a structure. A woman went into a confinement and did not come out of it, and the thing she left behind was a son who would live sixty-five more years and spend a great many of them attempting, in ways he never once described in those terms, to be worth the exchange.

Her name was Paula. She was Siegfried Haber's wife and she was also his first cousin, which is the second fact of this life and is usually printed as a curiosity when it is in fact a piece of architecture. First cousins share a set of grandparents. The marriage therefore did not join two families; it folded one family more tightly into itself. When Paula died the widower did not lose a wife who had come to him from somewhere else, with a household of her own behind her, with parents who might take the infant for a season and raise him in a house where the loss was differently shaped. He lost a kinswoman. The mourners on both sides of the grave were the same mourners. Whatever was said about the death, and whatever was decided about the child, was said and decided inside a single connected family that had every reason to keep the arithmetic of it private and no outsider present who might have written it down. Which is, in the event, exactly what happened. Nobody wrote it down.

It is important to state at the outset what the record of this month does not contain, because the temptation to fill it is going to run through the whole book, and a biographer who yields to it here will yield to it later, in places where the stakes are chlorine. The cause of Paula Haber's death is not established by the sources this book rests on. There is no letter of hers here, no description of her by anyone who knew her, no account of her illness if she was ill, no report of what she said or whether she was conscious at the end, and no photograph that this book can put a claim on. She is a name, a relation, and an interval. A three-week interval, measured from her son's birth, is the entirety of what the documentary record fixes about her adult life. It would cost nothing to give her a deathbed here, a farewell, a look at the child. This book will not, because those would be inventions, and they are the kind of invention that reads as tenderness while quietly manufacturing a person out of nothing.

Consider what three weeks means for the child, since that is the only side of it the evidence permits. It means he had no memory of her. Not a faded memory, not a memory contested by later information — none. An infant of three weeks retains nothing. His mother was therefore never an experience he could revise; she was information, delivered to him at some later date by adults who had their own reasons for how they delivered it, and thereafter fixed. This is not a small distinction. A child who loses a mother in boyhood has a person to grieve and, later, a person to argue with in his head. A child who loses one at three weeks has a fact to carry. Fritz Haber carried a fact. And the fact, however gently it was given to him, had a structure that no gentleness could remove: the woman was alive, then there was a birth, then she was not. Whatever the household intended him to understand, that is the sequence any child eventually assembles for himself.

Siegfried Haber was a merchant in dyes and pigments, and he raised the boy. That trade is worth pausing on, because it is the first environment of the life and because it was not, as the later story is usually told, a world away from what the son became. A dealer in dyes and pigments sells color. He buys substances whose entire value lies in a property that cannot be established by looking at the sack — whether the color is what it is said to be, whether it is what it was last time, whether it will hold in the cloth or fade out of it, whether it has been cut with something cheaper. His stock is judged on purity and on performance, and both are commercial questions before they are scientific ones. He is a man whose living depends on the behavior of matter under conditions he does not control, and whose expertise is entirely applied. There is no theory in it. There is a price, a sample, a customer who will or will not come back.

This is the atmosphere the son grew up breathing, and it is the atmosphere of his working life. Haber never became a discoverer in the pure line. His method, in the laboratory at Karlsruhe and afterward in the institute at Dahlem, was to take a reaction that worked on a bench and force it to industrial scale — to make somebody's chemistry enormous, and useful, and salable. He was not the man who found the principle. He was the man who made the principle produce. The house he was raised in ran on precisely that distinction: nobody in a pigment warehouse cares why a color holds, and everybody in it cares whether it does. It would be too much to say that Siegfried Haber's trade determined his son's, and this book does not say it. It says only that when Fritz Haber later chose the applied over the pure, and chose it with a consistency that looks like temperament rather than circumstance, he was choosing something he had known since before he could name it.

There is a second inheritance in that warehouse, and it is the one this book is named for. A merchant keeps accounts. His trade is quantities — weights bought and weights sold, what a thing cost against what it fetched, what is owed and by whom — and his world is one in which every transaction carries a number and the numbers are expected to come out even at the end of the year. A child raised over a business of that kind absorbs a proposition too basic ever to rise to the level of belief: that things can be counted, that what is owed can be stated, and that an account left open is a fault in the bookkeeping rather than a condition of life. Fritz Haber would go on to apply that proposition to soil, to explosives, to the ocean, and at last to the human lung, and in every one of those applications it worked, in the narrow sense that the arithmetic came out. What nobody appears to have given him, in that house or in any of the institutions he entered afterward, was the idea that certain accounts are not of a kind that can be settled at all. The first one he was handed was of exactly that kind. He was three weeks old when he received it, and he was still carrying it in Basel.

Of the relationship between the two of them in the Breslau years, the record is meager and the temptation is enormous. The sentence that wants to be written is that Siegfried raised a son he could not look at without seeing the cost. It is a good sentence, it may well be true, and it is an inference rather than a finding: no document produced in that household says it, and none says the opposite either. What can be stated without inventing anything is smaller and still worth stating. The house contained a widower, a motherless boy, and a piece of knowledge about how the second had produced the first. Whatever accommodation those three things reached, they reached it in private, and nobody present had any reason to record it.

A reader is owed the shape of the evidence at the start of a book like this one, so here it is. For the Breslau years the outward facts are good: the date, the place, the family, the trade, the death and its interval are all documented, and this book has not had to guess at any of them. The interior is inference — all of it, without exception, and the inference is being made at long remove by people with theories. Any biography of this man has to proceed at this point by reasoning backward from the adult to the child, and this one is going to do the same, because there is no other route available. The difference between an honest version of that procedure and a dishonest one is not the reasoning. It is whether the book tells you it is reasoning.

That principle has a practical form, and it should be stated here because it will matter most at the worst moments of the story. This life has places in it where the record simply stops. There is a death in the middle of it that nobody has ever explained and for which no note is known to survive. There is a promotion whose date the German scholarship and the English accounts do not agree on, and the meaning of the man's most famous act moves depending on which is right. There is a casualty count for which the older accounts give figures several times higher than the ones modern scholarship supports. At each of those places this book intends to stop where the evidence stops and say so on the page — to set out the readings that are on offer, to grade them, and to decline to choose between them where choosing would mean inventing. This will be unsatisfying in exactly the places a reader most wants satisfaction. That is what the evidence is like. A biography that never admits ignorance is not telling you about its subject; it is telling you about its author.

So: the reasoning. What is unusual about Fritz Haber is not that he lost his mother, which was common, and not that he did not get on with his father, which is commoner still. It is that his existence and her death were the same event, and that this was not a secret in the family but a plain and unmentionable fact — the sort of thing everyone knows, nobody says, and the child works out on his own at whatever age children work such things out. There is no villain in it. Nobody blamed him; there is no evidence anyone did, and it would be a slander on a dead household to suggest it. That is precisely what makes it durable. An accusation can be answered. A debt that nobody has ever presented, to a creditor who died before the debtor could see her face, cannot be answered, cannot be settled, and cannot even be argued about, because to raise it would be to accuse the family of an unkindness it never committed.

What does a person do with an obligation of that kind? He does not grieve it, because he has no one to grieve. He converts it. He becomes useful. And because the original account can never be closed — no quantity of usefulness discharges a life — the payments do not stop and they do not stay the same size. They escalate. This is the pattern that runs through everything that follows in this book, and it is the reason the Breslau chapter is not a formality. Look ahead at the shape of the career and what stands out is not brilliance, of which there was a great deal, but scale, which is a different quality altogether and a more revealing one. When Haber solved a laboratory problem he was not finished until the solution was feeding a continent. When his country needed a weapon he did not deliver a proposal; he buried cylinders along a front and stood on the ridge to watch. When Germany was ruined and owed money it could not pay, he did not decline the problem as absurd; he sent expeditions to sea to strain gold out of the ocean. In each case the response is not proportionate to the request. It is proportionate to something else, something the man never named and possibly could not have.

The honest objection to all of this has to be put on the page too, and put fairly. A great many children in that century lost their mothers to childbirth, and the overwhelming majority of them did not grow up to change the chemistry of the planet. The childhood cannot be the cause. Loss on its own explains nothing, because loss on that scale was ordinary and Haber was not. What a beginning like his can supply is not force but shape — not the drive itself, but the direction the drive took and the peculiar impossibility of satisfying it. Plenty of ambitious men want to be first. Haber wanted, all his life and in a way that made even his admirers uncomfortable, to be needed, and to be needed by something large enough to be worth the price of him. It was never going to be a discipline. It turned out to be a country.

Hold the ending of the story next to its beginning for a moment, because the rest of this book is the distance between them and the reader should know how far it runs. The infant of December 1868 became the man whose reaction pulled nitrogen out of the air and put it into the soil, so that roughly half the nitrogen in a living human body has now passed through it — a claim that belongs to Vaclav Smil and to the peer-reviewed work that followed him, and that this book will support in its proper place rather than assert here. He also became the man who stood on a ridge north of Ypres on April 22, 1915, and watched 168 long tons of chlorine roll downhill into the French line. Those are not two men; that argument is the reason this book exists. And in 1933 the country he had served past the point of his own marriage and his own conscience informed him that he was a Jew, and he left it, and he died on January 29, 1934, at sixty-five, in a hotel in Basel, on his way to a laboratory in Palestine he never saw.

One further fact belongs to the birth rather than to any later chapter, although every later chapter turns on it. The family was Jewish. That is an entry in the record of December 1868 and nothing more complicated than an entry, and it is set down here without commentary, because what it cost, what it could be traded for, and what it turned out in the end not to be tradable for at all is the business of the chapter that follows and of the chapter, far away at the other end of this book, in which a decorated front-line officer of the Imperial army is informed by his own government of something he had spent a working life declining to be. In Breslau it was simply a description of a household: a merchant family, in the Jewish community of a Prussian city, in a kingdom that had opinions about both halves of that sentence.

He was still in Breslau until 1886. The standard reckoning of the life closes the childhood there and opens the next phase with his going away to study, which is the business of the chapter that follows this one. What he took out of the city with him cannot be inventoried, because nobody inventoried it. What can be said is that he left a place where his family was known, where his father's business had a name over it, where his mother's kin were his father's kin, and where every adult he had grown up among had been present, in some capacity, for the event that opened his life. He would not, in the whole of the rest of it, live anywhere so thoroughly accounted for.

There is a last thing about Breslau that has nothing to do with him and everything to do with reading his record now. The city is not called Breslau anymore. The Silesia he was born into is not the Silesia on a current map, and a researcher who wants the surviving municipal and university papers of his birthplace writes to the archive of the University of Wrocław, in Poland, under a name the city did not carry when he was alive. This is not a flourish. It is a working condition of the book, and it belongs at the front of it. The country Fritz Haber spent his life proving himself to did not keep the ground he was born on, did not keep him, and did not, in the end, keep its own name for the place. He served a Germany that did not survive him in the form he served it.

The book takes its title from a formula he wrote much later, in the middle of the gas war: a concentration multiplied by a duration, resolving to a constant. It was the first formula the science of killing was ever given, and it is characteristic of him in every respect — practical, clarifying, coldly useful, and monstrous in a way its author appears never to have felt. That formula is the reason the subtitle of this book contains the word arithmetic. But the accounting starts earlier than the war, and it starts in Breslau, with an entry made in the first month of a life: a woman's life on one side, a child on the other, and an equals sign nobody in that family was ever going to write down. He spent sixty-five years paying into an account that could not be balanced. The final chapter of this book will find it still open.