The damage from oxygen is also one reason humans are made up of two sexes. Every cell in our bodies possesses tiny powerhouses called mitochondria, which are the locations where all the oxygen burning takes place. These mitochondria are at the forefront of all the free-radical damage, and it's crucial to make sure that the ones handed down to the next generation are free from the damage that comes with aging. A woman's eggs are born with her, and spend their lives using essentially no energy at all. Their mitochondria are kept in pristine cold storage, ready for the children to use, which is why eggs sit and wait to be fertilized rather than going off in search of a sperm.
Meanwhile, every time a man's sperm are regenerated, the mitochondria the new ones contain are a little older. They also use plenty of energy to swim along and find the stationary egg. But after that—and here's the clever part—the mitochondria from the sperm get jettisoned, like spent rocket stages. So every child inherits pristine mitochondria from its mother, and the aging clock doesn't start ticking until the fetus starts to form. If we had only one gender to play with, this couldn't happen. Hence the troubles, and glories, of romantic relationships between men and women are born in the chemistry of oxygen.
The lesson of oxygen shows that many things that are exhilarating have their own attendant dangers: making discoveries, making enemies, challenging the authorities, falling in love. Indeed, everything about our vigorous, dynamic lifestyles comes with its own terrible cost. For our agile minds, our strong bodies, our different sexes, for the power of movement itself, we have to accept the inevitability of old age and death. The oxygen in each breath you take brings you everything that's worth living for, but it will ultimately make you pay with your life. Within its chemistry lies the very heart of the human condition.
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Lavoisier didn't know the extraordinary ways that oxygen has shaped our world and our lives, but he did know that he had proved that the most essential and vibrant ingredient for life comes from the air. He had also discovered that we breathe to burn our body's fuel, something that came as a great surprise to scientists of the eighteenth century. Until that point, eating and breathing were considered wholly unrelated activities. And this led the fair-minded Lavoisier to an uncomfortable conclusion. "As long as we considered respiration simply as a matter of consumption of air," he wrote, "the position of the rich and the poor seemed the same; air is available to all and costs nothing."
Now, however, it was clear that when people worked harder and hence breathed faster, that meant they were also burning up more of their body's food. "By what mischance," he demanded, "does it happen that a poor man, who lives by manual work, who is obliged, in order to live, to put forward the greatest effort of which his body is capable, is actually forced to consume more substance than the rich man, who has less need of repair? Why, in shocking contrast, does the rich man enjoy an abundance which is not physically necessary, and which seems more appropriate to the man of toil?"
This was a good time to ask. Lavoisier and Laplace published their findings in a Memoir to the Royal Academy of Sciences in 1789, the year of the revolution. The reign of Louis XV's feeble grandson and heir, Louis XVI, had come to a violent end. The Bastille had fallen, and Paris was replete with the promise of change. Filled with optimism, convinced that his beloved France finally faced the prospect of real reform, Lavoisier wrote that one should not chastise nature for the "shocking contrast" that he and Laplace had uncovered. "Let us rather rely on the progress of philosophy and humanity, which unite to promise us wise institutions, which will tend to equalize all incomes, to raise the price of labor, and to ensure its just reward; which will obtain for all social classes, and particularly for the indigent, pleasure and happiness in greater abundance."
Over in England, Priestley continued to bicker with Lavoisier by mail about the existence or otherwise of phlogiston, but he, too, was thrilled by the fall of the Bastille. Taken together with the newly independent America, Priestley decided that the world faced "a most wonderful and important era in the history of mankind." "We may expect," he went on to declare, "to see the extinction of all national prejudice, and enmity, and the establishment of universal peace and good will among all nations."
If only their political instincts had matched their scientific ones! For as well as all those attributes that had enabled them to see in air what nobody had seen before—self-confidence, a certain tactlessness, fearlessness, refusal to take anything at face value, and a fervent curiosity—Lavoisier and Priestley had another thing in common. The French Revolution, which they each hailed with such delight, was about to destroy both of their lives.
JULY 14, 1791
BIRMINGHAM, ENGLAND
Two years to the day after the fall of the Bastille, the second anniversary of the beginning of the French Revolution, Joseph Priestley and his friends were preparing to celebrate. Priestley was no longer in the employ of the Earl of Shelburne. Eventually, his outspokenness had begun to embarrass the earl, who enjoyed the odd bit of revolutionary zeal but had realized that his own political ambitions were beginning to suffer from Priestley's diatribes. So Priestley had once again been forced to move, this time to Birmingham, to a house provided by his brother-in-law.
He wasn't too bothered by the change. Shelburne was still paying him a pension, and other patrons had stepped in to supply him with first-class scientific equipment to pursue his fascination with air. He had his library, his writing, his family around him, and the priceless company of other equally curious and indefatigable intellectuals: James Watt, inventor of the steam engine; Erasmus Darwin, grandfather of Charles, whose own declared aim was to "inlist Imagination under the banner of Science"; and Josiah Wedgwood, innovator with ceramics and founder of the famous china company that persists in England today, who was also the grandfather of Charles Darwin, since his daughter married Erasmus's son. These friends and enthusiasts met to discuss their ideas once a month, when the moon was full, to enable them to see their way home afterward. Thus they called themselves the Lunar Society, though when their ideas were at their wildest others were known to change that to "Lunatics Society." Priestley basked in the approval and stimulation of his newfound friends and sympathizers, and in some respects had never been happier.
He was also freer than ever to preach his uncomfortable, dissenting views. He had found a new position as minister in a local church, and divided his time most contentedly between studying air and writing about ways to ameliorate the lot of mankind. In particular, he continued to glory in the recent American and French Revolutions, which he felt demonstrated the beginning of the triumph of reason and merit over inherited elitism.
However, these events abroad were sending tremors of alarm through the English hierarchy, and a tide of patriotism was sweeping the country. In a climate such as this, it was tactless of Priestley to describe the prevailing establishment of church, monarchy, and aristocracy in England as a "fungus," which, he said, was sapping the juices of the country on which it parasitically fed. His was not a popular opinion among the loyal townsfolk of Birmingham, to whose ears Priestley's call for rational argument sounded more like treason. He was already used to seeing "Damn Priestley" scrawled up on the walls, and having small boys follow him in the street to repeat what their elders had evidently taught them. It didn't bother him much, because he was cheerfully conscious that it was undeserved.
But when his friends organized a dinner in honor of the French Revolution, rumors began to circulate that Priestley had called for the head of the king, and threatened to bomb the established Anglican churches, and later that same evening a rabble was roused. In an uncharacteristic burst of prudence, Priestley hadn't even attended the dinner. He was at home playing backgammon when there was a violent banging on the door and young men, breathless from running, stammered out their news. A mob had already smashed the windows of the hotel where the dinner had taken place and torched the church where Priestley preached. It was now heading for his house, hell-bent on murder
.
Priestley couldn't credit that he himself might be in danger. Who, after all, would want to hurt someone so evidently harmless? But he accepted that he might be subjected to some unpleasantness if he stayed, and he agreed to remove temporarily to the house of a neighbor. He calmly went upstairs, put a few papers and things of value where he thought no miscreants would find them, and left in the clothes he had been wearing. He told the servants to lock the doors, and if stones should be thrown to keep out of the way of the windows.
Priestley's son was less phlegmatic. He urgently did his best to secure the house, and doused every fire and every candle. At midnight the mob arrived. The weather was calm and clear, and from his neighbor's house barely a mile away Priestley could hear every shout and curse, every stroke of the implements used to break down the doors and windows. Next came the splintering sound of smashing furniture, followed by the shattering of glass. With increasing horror, Priestley realized that they were not just breaking the windows; they had started on his scientific instruments. His beloved laboratory had been one of the best equipped in Europe. Now, helplessly, he was witnessing its destruction.
Worse was to come. They were seeking a fire. They wanted to torch his library. Priestley listened in anguish as the mob sought, at first in vain, for a flame. Somebody shouted, offering a full two guineas for a lighted candle. Priestley thought of the diaries that he had been keeping almost every day for the past forty years, each with its own record of his state of mind, his hopes, and his intentions and prospects for the year ahead. He thought of the many notebooks containing the fruits of his reading almost since he had first learned to formulate his opinions. In his library, too, was every sermon he had ever written; his memoirs, which were to have been published after his death; every letter he had ever received, from dear friends and learned foreigners.
And he thought, too, of his books. It had been his custom to read always with a pencil in his hand, marking the passages that he wished to look back to, or that he thought would be particularly useful for some new endeavor. He would make an index to such passages on a blank leaf at the end of the book. His library, his precious library, contained not just books, but the chief fruit of his labor and judgment in reading them. The fate of all this rested on whether or not the mob now despoiling his house could lay their hands on a flame.
And then, from somewhere, somehow, they found one. What was first an orange glow reddened as the fire took hold. It burned every bit as brightly as the candle that had enchanted Priestley when he first thrust it into his dephlogisticated air. Fed by copious amounts of the oxygen that had already made him famous, its flames ripped through the pages on which he had explained their secrets. They showered incandescent debris over the fragments and shards that were all that remained of his glass retorts and beakers, experimental chambers, even the giant burning glass that had first revealed oxygen to the world. Everything was destroyed.
During the course of this long night, Priestley had been planning his next sermon, to be preached among the ruins of the meetinghouse using the text "Father forgive them, for they know not what they do." But when he felt the force of the mob's anger, he realized that all hope of reasoned arguments was gone. Harried constantly by fresh news of impending danger, he fled from this house to that, to London, and eventually to exile in America. He was safe there, and so was his family. But he was more than sixty years old and much of his life's work lay behind him, in ashes.
In France, Lavoisier had problems of his own. He had no particular reason to fear the revolution; indeed he had hailed it. Though extremely wealthy, he was no aristocrat, and he had long bemoaned the foolish way his country had been run, for the sole benefit of a privileged, and in his opinion often worthless, hereditary elite. The Ferme Générale's contract for tax collection had been cancelled by the National Assembly a few months earlier, but Lavoisier had already made his fortune, and had neither the need nor the desire to continue his work there. Instead, his problems—at least at first—stemmed more from the energy that he felt obliged to pour into attempts at social reform.
As one of the most highly educated and progressive minds in the country, Lavoisier felt bound to devote virtually all his time to public service. He became chief financial adviser to the government, introducing a highly efficient system of bookkeeping into what had been the murky fog of national finance. He drew up detailed reports on the agricultural and industrial prospects of the country and demonstrated, in what one contemporary called a "calcul très patriotique" (highly patriotic calculation), that the nobles had composed barely 3 percent of the population. With all these activities, no time remained for him to pursue his many scientific ideas, and he much regretted his own beloved, and now neglected, laboratory.
But worse trouble lay ahead for Lavoisier in the form of an old enemy, Jean Paul Marat. Marat's life story was an unfortunate one, full of desires that he could never quite fulfill. Employed as a medical officer by an infamous royal aristocrat, the Comte d'Artois, he had plenty of opportunities to witness the privileges of wealth firsthand, but remained frustratingly unable to experience them for himself. The same went for science. He desperately wanted to make his name as a man of science, and once, years earlier, had presented a treatise to the French Royal Academy. In it, he declared that a candle goes out in an enclosed space because the air becomes dilated by heat, and eventually smothers the flame. Lavoisier, a leading light of the Royal Academy, had been contemptuous of this work. It was not only wrong; worse than that, it was sloppy. Lavoisier, who required precision in all things, ensured that Marat's treatise was rejected, and he himself made sure that Marat was prevented from claiming the approbation of the Academy when he wrote up his work.
Marat never forgot. And now, in the early years of the Revolution, when little had yet changed in the lives of the poor people of Paris, Marat had become the spokesman for the mob. Finding himself at last in a position of power, he saw his chance for vengeance. He began to denounce this Lavoisier, "son of a land-grabber." In particular, he focused on one of Lavoisier's least popular achievements. In his position as a Fermier Général, Lavoisier had had a wall built around Paris. Typical of his mindset and reminiscent of his scientific experiments with air, it was a superbly efficient and accurate way to seal off the city and then catalog every item that entered or left, to calculate the appropriate taxes. Marat's criticism of this was brilliant in its irony. He declared that this wall, built by the man who had given the world oxygen, had blocked the city's supply of air.
Lavoisier failed to see the danger. He made no effort to escape from Paris until the heat died down, nor did he seek to defend himself from Marat's foolish accusations. The world had always been good to him. Rational and scientific arguments had always prevailed, and Lavoisier saw no reason that should change. But, like Priestley, Lavoisier was relying on reason at a time when reason had temporarily lost its grip. For the Revolution had turned on itself. In this new time of Terror, a whisper was all it took, and Lavoisier found himself abruptly imprisoned, along with many of the other former Fermiers Généraux, without even knowing the charge.
The trial took place on May 8, 1794. Acts of accusation had arrived the night before, one for each prisoner, but candles were forbidden and it was too dark in the prison to read what later proved to be ludicrously trumped-up charges. The counsel appointed to defend Lavoisier didn't show up for the trial, and it probably would have made little difference if he had. The judge, one Pierre-André Coffinhal, was already famous for his barbarity, and for his love of playing to the crowd. After condemning a former fencing master to death he is said to have declared: "Well, old cock, parry that thrust if you can." He glibly refused to allow Lavoisier's carefully penned statements, or those of his friends and supporters, to be read before the court. He encouraged the jury to laugh uproariously at anything the accused tried to say. Several of the former Fermiers were unexpectedly whisked away partway through the proceedings; a word spoken somewhere in the right ear by the r
ight person had earned them a last-minute reprieve. No such word came for Lavoisier. The bust of Marat stared down at him throughout the trial. When the verdict came, it was a formality. He and the rest of the remaining Fermiers had been found guilty of the capital crime of plotting against the Republic. A final plea for a two-week stay of execution to enable Lavoisier to complete some scientific work that would be of great value to mankind was dismissed by the judge in the now-famous words: "The Republic has no need of savants. Justice must take its course."
There was no more time for arguments. Lavoisier was taken immediately into an anteroom, where his hands were tied behind his back and his hair cut off at the nape of his neck. Next he was squeezed into a tumbrel with the other condemned prisoners, to make the short journey to the Place de la République. Lavoisier was the fourth to be executed, immediately after his father-in-law. The whole operation took about a minute: Mount the steps to the scaffold, lay your head on the block, listen as the blade rattles back upward, ready to begin its descent. As the blade fell, Lavoisier took his final breath of the vital air that would make him famous. "It took them only an instant to cut off that head," said a friend and fellow thinker, astronomer Joseph-Louis Lagrange, when he heard the news. "And a hundred years may not produce another like it."
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An Ocean of Air Page 7