Notes

CAESAR’S LAST BREATH NOTES

 


Chapter One

Air Speed

As noted, an average molecule of air at 72°F zips around at roughly a thousand miles per hour. That’s far faster than the molecules in liquids or solids move. But even in solids at extremely low temperatures, hundreds of degree below zero, atoms never quite sit still. They vibrate in place or, if bonded to other atoms, hinge and twist and pivot back and forth. So technically, it’s wrong to say that perpetual motion doesn’t exist. It does, on atomic scales.

Before you go telling people this at parties, though, remember that perpetual motion machines cannot exist, because you can’t harness this perpetual atomic motion to do work. Sorry.

p45

In the days after Mount St. Helens blew, students in colleges in eastern Washington dropped out by the thousands, fearing that if they stayed through finals they would catch something called pneumonoultramicroscopicsilicovolcanoconiosis, a lung disease that results from inhaling fine silicon particles. Readers of my first book, The Disappearing Spoon (a romp through the periodic table) might recognize this disease (a.k.a. “p45”) from the discussion of the longest word in the English language. It’s no match for the 1,185-letter, carbon-based word that appears on page 33 there, but it’s pretty good.

Coleridge

The reincarnation of Spirit Lake at a higher elevation always reminds me of Alph, the “sacred river” in Samuel Taylor Coleridge’s poem “Kubla Khan,” which forced itself upward after an earthquake nearly buried it and proceeded to devour Kubla’s pleasure dome.

Interlude 1A

Lake of Babel

Eyewitness testimony around Lake Nyos remained confused for other reasons as well, beyond possible hallucinations from carbon dioxide poisoning. The incredible linguistic diversity of the region—roughly thirty different languages are spoken there—made finding translators for difficult, and it’s not clear whether everyone’s original testimony got recorded accurately.

Venting Nyos

The pipe that vents CO2 from the bottom of Lake Nyos works as follows. There’s a pump at the top that starts the water flowing upward. This decreases the pressure at the top, allowing water from below to rise within the pipe. Eventually the CO2-rich water at the bottom of the lake starts to rise, and as it gathers momentum it whooshes out the top.

Chapter Two

More German Nitrogen Chemistry

Not long before Haber’s breakthrough in synthesizing ammonia, a German chemist named Wilhelm Ostwald developed a method to convert ammonia (NH3) into nitric acid (HNO3). However dandy this was—nitric acid is a vital industrial product, and Ostwald won the Nobel Prize for the work in 1909—manufacturers still needed a way to produce ammonia. Hence their asking Haber to try his hand at the job.

Bonds Beyond Three

Triple bonds generally bind atoms together more strongly than double bonds, and double bonds more strongly than single bonds, but that pattern doesn’t hold in all cases. Incidentally, the strongest bond in nature, stronger even than N≡N, is the C≡O triple bond, which is 14 percent tougher. Quadruple and quintuple bonds exist in some metals.

More on Manure

In addition to creating fertilizer, the composting of manure can produce a nitrogen-rich substance called saltpeter, a vital ingredient in gunpowder. As a result, governments that coveted gunpowder (i.e., all of them) coveted stores of manure as well. A few kings of England even appointed officials called petermen to collect manure, by force if necessary. Indeed, petermen had tyrannical powers to tear up floorboards in stables, evict people from their homes, and steal horses and carts to haul saltpeter around. People reportedly loathed petermen even more than taxmen, which is saying something.

Chinchas Weather

It basically never rains in the Chinchas for a few reasons. The prevailing winds blow from the east, and the Chinchas lie very near the Andes mountains along the South American coast, some of which reach 23,000 feet. Air cools significantly at such heights, so any moisture in it condenses out as rain or snow on the mountaintops, leaving little water behind. This creates a huge “rain shadow” along the coast, a penumbra that includes the Chinchas. In addition, a permanent high-pressure zone in the nearby Pacific Ocean fends off any rainstorms trying to muscle their way in from the west.

Another factor is a nearby current of cold ocean water that comes rushing up from Antarctica. Normally, air near the ground is warmer than the air above. Warmer air tends to rise, and as it does so, it carries with it moisture that precipitates out as rain. The current from Antarctica, however, cools the air near the ground, leaving it colder than the air above. This “temperature inversion” is more or less permanent, and it prevents the formation of rainclouds near the Chinchas because the moist air below can’t rise.

All of these forces conspire to eliminate rain there, and most people who live near the Chinchas don’t bother with roofs on their houses. Flies don’t exist there, since there’s nothing for them to snack on. Even bacteria are hard to come by. Archaeologists have found several perfectly preserved mummies in the Atacama desert on the mainland near the Chinchas, including mummies of children, since there’s nothing to decay them. As the crow flies, the Chinchas lie fairly close to the ultra-humid Amazon rain forest, but they might as well be on different planets.

Modern Starvation

Sadly, despite the Haber-Bosch process, people still starve today in certain parts of the world. But most experts blame that fact on political problems that disrupt food delivery or keep prices exorbitantly high. Human beings do grow enough food around the world to feed everyone who exists, at least for now.

German Arrogance

Haber wasn’t the only German scientist whose reputation suffered abroad. Shortly after the war started, a “manifesto” began circulating in Germany that laid the blame for the conflict, rather ridiculously, on the Allies, who had supposedly threatened the German people’s right to exist. Haber eagerly signed the document to show his support, as did Walther Nernst, Max Planck, and several leading artists, theologians, jurists, and historians. Meanwhile, the document horrified Albert Einstein, and scientists across the world learned the sad lesson that even the most brilliant artists and scientists are not immune to being brainwashed by propaganda.

The Timing of WWI

Because Haber’s ammonia process also helped Germany make more gunpowder, rumors have always circulated that Germany waited to start World War One until Haber and Bosch had worked out all the kinks. Most historians doubt this, however, since German military leaders were convinced they’d plow through the French lines in a few weeks. Bosch also disputed this idea. In his experience, the German military command was too stupid to grasp the importance of ammonia production. The timing of World War One was nevertheless suspicious.

Defending Bosch

The book mentions that, during World War Two, the Germany military surrounded Bosch’s synthetic gasoline plants with the best aircraft-defense system in Europe. It worked so well because gunners didn’t bother tracking and firing at individual planes. Instead they created overlapping firework bursts of shrapnel that covered every part of the sky, ensuring that the planes had no way to even approach the plants.

Nernst’s Consolation

Although fairly jingoistic at the outset, Walther Nernst lost both of his sons during World War One and emerged from the conflict a chastised man. In a preface to a book he wrote in 1917, Nernst said, “In times of trouble and distress, many of the old Greeks and Romans sought consolation in philosophy, and found it. Today we may as well say there is hardly any science so well adapted as theoretical physics to divert the mind from the mournful present.”

Interlude 2A

Caveat on Fletcher

Another caveat about different types of gas cutting: In Fletcher’s process, pure iron melts. This differs from oxygen-cutting, because in oxygen-cutting a chemical reaction takes place first, forming various iron oxides. The iron oxides do melt at this point, but again, that’s different than the melting of pure iron. That distinction is worth making because while the end result is the same—a hole in the metal—the order of the steps differs, and the oxygen-cutting/slag-melting process take place far more quickly.

chapter three

Priestley’s Greatest Happiness

As another example of Priestley’s influence in politics, it was he, not Jeremy Bentham, who coined the phrase that soon became the ultimate goal of utilitarianism, to provide “the greatest happiness for the greatest number.”

Boyle vs. Hooke

Many historians argue that we should call the pressure-volume relationship for gases not Boyle’s Law, but Hooke’s Law, after Robert Hooke, the scientist who helped discover what the lungs do. Boyle was the classic gentleman-scientist—rich, well-connected, arrogant—and Hooke essentially worked for Boyle and others at the Royal Society in London, helping them carry out experiments. Boyle was no dummy, certainly. But he felt that it was his right to take credit for Hooke’s work, including both the volume-pressure law and the development of the air pump.

Ancient Elements

Depending on what sources you consult, the ancients knew of around a dozen pure elements: iron, copper, carbon, gold, silver, zinc, mercury, tin, antimony, lead, sulfur, and arsenic. Alchemists beginning in the mid-1600s then discovered a half-dozen more over the next century. But none of them were gases. The first elemental gas was discovered only in the 1760s, hydrogen. But several more quickly appeared after that: oxygen, nitrogen, chlorine.

Fixed Air

Joseph Black first created CO2 it by mixing limestone (CaCO3) with acids in 1754. In observing this process, he reasoned that the solid limestone had somehow released a gas contained inside it. (Hence Black’s name for carbon dioxide, “fixed air,” since the gas seemed fixed or trapped inside the limestone.) Given the paucity of chemical knowledge then, this wasn’t a bad guess. And as the explosives chapter shows, there is something in the idea that certain liquids and solids are simply gases waiting to be loosed upon the world.

Johnson on Priestley

In Life of Johnson, Samuel Johnson complains thusly about Joseph Priestley: “Of Dr. Priestley’s theological works, he remarked that they tended to unsettle everything, and yet settled nothing.” That seems like a fair criticism. Priestley did have a tendency to stir up trouble—both in science and religion—but without offering ideas to replace those that he rejected. For this reason his theology proved no more tenable for most people than his beloved theory of phlogiston.

Shielding Scheele

The book mentions that Lavoisier and Priestley once met and discussed chemistry over a meal in Paris. Curiously, Lavoisier also had contact with Carl Scheele, in the form of a letter in the early 1770s. In it Scheele described his experiments with fire-air and asked the great French scientist if he could help interpret them. No one knows whether Lavoisier ever saw or read this letter, but it was found among his wife’s things decades later.

Anaerobic Archaeology

In addition to multiplying like mad inside your mouth, anaerobic bacteria also thrive in certain lakes that lack free oxygen in their depths, like the Black Sea. This explains why many wooden ships, despite sinking several thousand years ago, have survived intact at the bottom of these lakes, because there’s nothing to decay them. The bodies of sailors who went down with them might still be intact as well.

Eating Light

The discussion of photosynthesis reminds me of a great line. In the 1980s it became something of a fad for people to play Mozart to their houseplants, to help them grow. Tim Plowman, a noted ethnobotanist, would always make fun of such people. “Why would a plant care about Mozart?” he’d say. “And even if it did, why should that impress us? They can eat light—isn’t that enough?”

Animals Before Oxygen?

I should point out that some scientists now question the tidy assumption that animals couldn’t have evolved without high levels of O2. In particular, they argue that sponges (the first animals) seem to have appeared in the fossil record when oxygen levels were just a few percent of what they are today. Regardless, complex animals definitely couldn’t have evolved without oxygen. Not to insult sponges, but unless our conception of “thinking” is laughably wrong, not much is going on upstairs there. In fact no animals with expensive tissues like muscles, eyes, and brains ever appeared before the oxygen boom a half-billion years ago, and then suddenly they were everywhere.

Priestley Conspiracies

After the destruction of his home, Joseph Priestley pleaded with the government for several months for restitution. While he waited, he also wrote a scathing account of the riots, accusing public officials in Birmingham of condoning if not outright inciting the violence. Some surviving evidence suggests he might be right.

Marat’s March

Ironically, because of some official posts he held in the French government, Antoine Lavoisier was obliged to march in a parade honoring his arch-enemy Jean-Paul Marat after the latter’s death, even though Marat despised Lavoisier and had done everything in his power to ruin him.

His Final Honor

Oddly, Lavoisier received his final scientific honor right before his execution, while jailed in probably the most squalid chambers he’d ever known in his life. It happened when an official from the Academy of Arts visited his cell and handed him a metal crown decorated with stars, in honor of his work. Under the circumstances it must have felt like mockery.

Chapter Four

Beddoes’s Early Inclinations

Thomas Beddoes seemed to have a predilection for medicine from a young age. At seven he watched his grandfather get thrown from a horse and puncture a lung on a pile of timber. Rather than scream or faint dead away, the boy found himself strangely calm, fascinated by the blood and the wound. Afterward he vowed to study medicine himself. But instead of focusing just on the physical side of medicine, his radical politics eventually led him to embrace its social aspects as well.

Art = Science

Even after he became the world’s most famous scientist, Humphry Davy confessed that he still considered himself a poet and storyteller deep down. Above all he wanted to astound people, and he didn’t much care whether he did that through stirring words or startling facts about nature. Beddoes wrote poetry, too, but not very well. He once bragged that he could compose a poem as fast as he could dash off a letter to a friend—which might feel satisfying, but isn’t exactly a recipe for immortal verse.

Speaking of poets, early in his career Davy used the prestige of his old nitrous buddy Samuel Taylor Coleridge to boost his own standing among the public. A few decades later Davy returned the favor and helped Coleridge, who’d gotten burned out with verse and had all but gone into hiding, to restore his name and reputation.

Davy’s French

As a youth Davy took French lessons from an exiled priest in Cornwall, but according to legend he never bothered learning to speak the language; he simply wanted to read Lavoisier and other French chemists in the original.

Davy’s Desires?

Davy reportedly found the company of Beddoes’s twenty-four-year-old wife, Anna, far more congenial than that of Beddoes himself. In fact, rumors have always swirled that Davy and Anna saw quite a little bit of each other during their free time—more than was strictly proper. There’s no hard evidence that they ever consummated this affair, however, so I’ll have to content myself with simply passing along this centuries-old scuttlebutt.

Good For What Ails Ya

Beddoes, an experienced doctor, noticed one other unusual aspect of gas work: unlike with most medicines and tinctures and tonics—which usually tasted terrible and left the patient feeling rotten—patients actually looked forward to inhaling nitrous, since they felt so buoyant under its spell.

Speechless

Peter Mark Roget of thesaurus fame also visited Davy’s lab to huff ether. In contrast to most people, Roget had a wretched time: he grew terrified that the earth below his feet was about to reach up and swallow him, and he dropped the green silk bag of gas in panic. Historians have also found it ironic that Roget of all people struggled to come up with words to describe his experience later.

The Symphony of Consciousness

Here’s another analogy to help illuminate the relationship between brain waves, anesthesia, and consciousness. You can think of brain waves as a measure of disorder—which sounds bad but isn’t, not entirely. The brain waves of comatose patients are tidy and simple, like a philharmonic orchestra playing a warm-up note: it’s not unpleasant, but it’s not exactly taking advantage of the players’ talents. As the brain wakes up from anesthesia, the musicians can start playing scales and arpeggios, breaking up the monotony. Eventually different sections of the brain can communicate and jam together. When the brain wakes up fully, that’s the real music: it’s still structured, but there’s enough turmoil to keep things interesting. You don’t want the brain to stray too far into bedlam; that’s seizure territory. But there’s a sweet spot in there, and you can watch the brain settle into it as patients emerge from anesthesia.

Anesthesia and Global Warming

As I mention later in the book, nitrous oxide contributes to global warming. And while not nearly as abundant as carbon dioxide, each N2O molecule absorbs heat something like 298 times more efficiently. The most common anesthesias used in surgery today are even worse. A single molecule of desflurane equals 2,500 molecules of CO2. Thankfully desflurane and other gaseous anesthesias constitute a tiny fraction of the atmosphere, just one in every ten trillion molecules.

And as long as we’re here, I should note that there are some caveats to consider when discussing how bad certain molecules are for global warming. A methane molecule absorbs heat sixty times more effectively than CO2. But because methane degrades more quickly, its “global warming potential” is only twenty-five times higher. There’s a similar numerical discrepancy for other global-warming gases: you always have to take into account both how well they absorb heat and how long they last in the atmosphere. CFCs are particularly bad on both accounts.

Interlude 4A

Methane’s Talents

As mentioned, methane has a reputation as being the smelliest part of farts, even though it has no odor. But it is true that you can light methane—and therefore your farts—on fire. Pure methane burns with a pretty blue flame, much like a gas stove.

L’Affair Pétomane

Here’s what one sardonic newspaper reporter wrote about the L’Affair Pétomane. Mind the puns. “When the director of the Moulin Rouge heard of this escapade [i.e., him serenading someone in the gingerbread stall], he had the idea of going after him and bringing him back with some well-placed kicks in—his musical area; but … not wishing to damage the instrument, [the owner] has preferred the law to stick its nose into this affair.”

Chapter Five

Defending Aristotle

Poor old Aristotle takes a lot of guff today for his “nature abhors a vacuum” argument, but his reasoning wasn’t ridiculous. Like Einstein 2,500 years later, he believed that nature had an intrinsic speed limit. He also believed that friction alone was responsible for keeping objects from going too fast. Since vacuums lack air (and therefore lack friction), that would mean that objects within them could accelerate to infinite speeds, which he thought absurd. QED, vacuums cannot exist.

How Many Horses?

Regarding the Magdeburg experiments, you sometimes hear different numbers of horses involved—thirty, sixteen, twenty-four, etc. That’s because von Guericke ran the demonstration many times, and for whatever reason used different numbers of horses in each.

Early Watt

Prior to working at the university James Watt had run a shop that sold buckles, pistols, nutcrackers, alarm clocks, and other trinkets. He also sold musical accessories, even though he himself detested music as frivolous.

Machine Volition

The ability of Watt’s engines to monitor their own behavior and slow themselves down astounded his contemporaries, since it made the machines seem self-aware. A goggled-eyed William Wordsworth declared that such machines had “life and volition.”

A True Steam Engine?

Many historians of technology have pointed out that Newcomen didn’t build a true steam engine, because the steam itself wasn’t doing any useful work. Rather, air pressure and the piston’s own weight were what pushed it down. Similarly, the beam wasn’t driven by steam, either: the piston was connected to the beam only via a chain, remember, and chains can’t push. What made the beam drop on the other side was actually gravity, since it was attached to a counterweight. This discussion isn’t meant to slight Newcomen: there’s no shame in using natural forces like gravity and air pressure, and he certainly exploited steam in his machines to raise the piston up and reset the apparatus each cycle. But if you want to get technical, the gas itself wasn’t driving anything, unlike with Watt.

Watt on Water

Although he did so a few decades after the first-known discovery of this fact, Watt independently determined that water wasn’t an element.

Atmospheric Railways

In addition to building steam locomotives, entrepreneurs in England in the 1800s invented “atmospheric railways,” underground railroads that relied on vacuum pressure within tunnels to push trains forward. Although the idea never quite caught on, the trains were silent and smokeless, and they could reach speeds up to 70 mph.

Steam Timing

The Newcomen engine’s combined heating/cooling step, in addition to wasting energy, also wasted time, which meant that the engine ran slowly. Watt’s separate heating/cooling apparatus allowed him to run the engines more or less constantly—exactly the kind of power that rivers provided and that looms and other complicated machinery needed.

Horse Power

The classic unit of horsepower is just an average; at peak exertion, a horse can (shield your eyes if you abhor contradictions!) produce twenty horsepower of work. When measuring horsepower for the first time, Watt devised a task that involved pushing a twenty-four-foot millwheel around in a circle. He found that an average horse could drag a load of 180 pounds 2.5 times around the wheel every minute, which worked out to roughly 33,000 foot-pounds of force per minute.

Nobel and Math

Legend has it that Alfred Nobel didn’t create a Nobel prize for math because of a personal grudge toward a mathematician. In reality, Nobel probably just found advanced mathematics too esoteric, too removed from everyday life. He probably snubbed basic biology for a similar reason.

Interlude 5a

One more clerihew

About Henry Bessemer:

“Corruptio optimi pessima!”

grinned Sir Henry Bessemer.

“Judicio vulgi demens!”

snorted Sir William Siemens.

(The first line means, roughly, “the corruption of the best is the worst of all.” The third line means, “judgment drives people mad.”)

A Near Miss for Mr. Bessemer

Bessemer’s father, Anthony, barely escaped Paris with his life during the French Revolution. He ran a bakery there, and a starving mob accused him of shaving his loaves—that is, of selling smaller-than-regulation loaves at regulation prices and pocketing the profits.

Bessemer vs. Kelly

If you look into the history of steel at all, you’re bound to come across an American named William Kelly, who supposedly invented the Bessemer process before Bessemer did. This isn’t a true example of Stigler’s law of eponymy, though, since Kelly never quite got the process to work. Kelly actually had no interest in steel when he bought his first foundry. He had merely purchased the land it was on because the acres happened to be near where his true love lived, and he wanted to show her father that he was a serious suitor. A few years later, when Kelly’s now-father-in-law heard his idea about making steel by blowing air into it, he referred the young man to a psychologist. Kelly proved so persuasive, however, than the shrink became a major investor. Anyway, rumors spread in later years that Bessemer himself had gone undercover in Kelly’s foundry to spy on the workings there. That never happened, but rival metalmongers did go incognito to steal steel ideas from Bessemer. A ruthless business.

Caveats on Bessemer Chemistry

The reaction of carbon and oxygen to form carbon monoxide not only removed impurities, it also released extra heat, which kept the iron liquid and easy to pour without the need for an external coal furnace. This cut down sharply on fuel costs and was a big reason Bessemer’s process succeeded.

In the chapter, I focused mostly on adding and removing carbon from iron, but Bessemer also faced major challenges removing other impurities from iron ores, like silicon and phosphorus. In fact, had other chemists not figured out how to rid his steel of these elements, the Bessemer process probably would have failed.

Finally, while Bessemer could and did make steel directly sometimes, he often found it easiest to ignite a runaway volcanic reaction with oxygen, strip the carbon out entirely, then add cheap carbon ores back in later.

chapter six

The Origins of Altitude Sickness

Chemist-balloonist Jacques Charles might well have been the first person in history to suffer from acute altitude sickness, although no one really knows. Possibly some of the more daring Tibetans throughout history beat him to it. And Robert Hooke in the 1600s had already suffered from the equivalent of altitude sickness when he immersed himself inside a vacuum chamber, and began pumping air out. He immediately fell sick with nausea and earaches.

Incidentally, many Tibetans seem to have a genetic mutation that protects them from the negative effects of living in the mountains. The human body naturally produces more red blood cells at higher altitudes. More red blood cells means the body can shuttle oxygen around more easily, which is the reason endurance athletes often train in the mountains. But the excess of blood cells also can contribute to clots. The Tibetan mutation reduces the chances of blood clots and thereby avoids this problem. Oddly, Tibetans seemed to have inherited this mutation from the Denisovins, a mysterious, Neanderthal-like species of humanoid that lived in Central Asia, among other places, and that interbred with humans as they spread east from Africa.

“Theoretical Flying”

As this chapter implies, the French dominated early aeronautical exploration, and for much of a decade the British Isles trembled in fear that Napoleon would invade England via balloon—a slow-motion ride of the Valkyries. That never happened, but Napoleon did use balloons to help conquer Egypt.

Ridiculously, the British scientist Sir Joseph Banks once tried to pooh-pooh the French superiority in the air by claiming that his country had a decided advantage in the all-important realm of “theoretical flying.” Meanwhile, mere “practical flying,” he said, “we may leave to our rivals the French.”

Highs and Lows

In May 1961, two Navy officers set a world record by ascending 113,740 feet (21.5 miles) in a hydrogen balloon, five times Charles’s height. It remains the highest altitude ever reached outside of space travel. The trip took ten hours, and exposed them to temperatures of –137°F and pressures roughly 1/200th of normal air pressure. (They made the flight in pressurized suits.) Sadly, one of the two men died during the stunt. He survived the ascent just fine, but during the pickup in the Gulf of Mexico, he fell while climbing into the rescue helicopter, got tangled in the balloon’s lines, and drowned when his suit filled with water.

The Real Gay-Lussac Law

Not to thumb my nose at another Joseph Gay-Lussac “discovery,” but just as Gay-Lussac was not the first person to discover the volume-temperature relationship in gases (that was Jacques Charles), he was not the first person to investigate the composition of high-altitude air. Two decades before Gay-Lussac did so, Henry Cavendish had examined a few vials of air captured during a high-altitude balloon flight. Like Charles and his gas law, however, Cavendish never published this work for some reason. If you were uncharitable, you might dismiss Gay-Lussac for simply rediscovering things that other people already knew. But it’s not his fault that they never published.

And Gay-Lussac did devise one gas law of his own. It says that when gases react chemically, they combine in small, whole-number ratios. That is, you always get something like 1N2+3H2à2NH3, with coefficients 1,3,2. You never get 2.71 or 4π or some other oddity. This provided, at least in retrospect, strong evidence for the existence of atoms, since it was individual atoms doing the combining here. John Dalton would later expand Gay-Lussac’s insights from gases to all matter and posit that all chemical reactions involve whole-number ratios.

Where Did the Nobles Go?

Based on the elemental composition of the sun (and by extension, the cloud of space gas that gave rise our solar system in the first place), Earth should have far more noble gases in its atmosphere than we do. The lack of these gases provides strong support for the theory that some sort of catastrophic impact occurred early in Earth’s history and boiled all these gases into space.

Blue Skies, Red Sunsets

The chapter explains why the sky above is blue, but the same general idea explains the reddish color of sunsets. In this case, the sun lies on the horizon, and the sunlight ends up traveling through more air on its way toward you. Traveling through more air means more scattering, and because of the geometry of the situation, with the rays coming right at you, only red and orange light gets through. In other words, the sky around sunsets isn’t blue because most of the blue photons get scattered away from your eyes. Dust from the ground and pollutants enhance this effect by scattering even more blue light.

Dearth of Helium

Helium should actually be much more abundant than argon in the atmosphere, since many heavy elements (like uranium) produce the gas as a byproduct of radioactive decay. The problem is that helium is so light, and the average helium molecule escapes into outer space after roughly a million years. Argon outnumbers helium, then, largely because it’s heavier and sticks around.

Jules Janssen’s Wild Ride

Of the 2.5 million people under siege in Paris, the German army offered just one, astronomer Jules Janssen, free passage to leave the city. But after months of suffering in solidarity with his fellow Parisians, Janssen refused. He did want to leave, desperately, and travel to Algeria to view an eclipse; but he informed the Germans that he would take to the air instead, and soar over the siege in a hot-air balloon. The Germans grumbled good luck—and warned Janssen that they planned to shoot his balloon out of the sky, then shoot him when he landed.

Given their history with hot-air balloons, it’s no wonder the French turned to them during the siege of Paris in 1870. Not that they had much choice. The wily German chancellor, Otto von Bismarck, had tricked France into invading that summer of 1870 and routed its army, even capturing Emperor Napoleon III and exiling him. Bismarck then swatted aside the French defenses and marched on Paris, surrounding it in just five weeks. (Some historians call it the original blitzkrieg.) Planning to starve Paris out, Bismarck’s men blocked every road and river out and cut every telegraph line. Within weeks, people in the city were chopping down trees on beloved boulevards for firewood. They took to eating pets, then vermin, then animals in the Paris zoo. Diaries from these months talk of rat pâté; Victor Hugo compared his stomach to Noah’s ark.

Desperate to communicate with the outside, the government in Paris began sending up hot-air balloons, each one carrying several sacks of mail and a cage of passenger pigeons for return messages. With typical flair, the French named the balloons things like La Liberté and La Délivrance; they also honored several scientists: Archimède, Davy, Lavoisier. Parisians filled the balloons with gas intended for their streetlights, sacrificing their reputation as the City of Light for the greater good. Unlike normal balloon flights, these commando flights aimed to get as high as possible as quickly as possible and skip over the dreaded German artillery. Germans soldiers took potshots anyway and sometimes scored hits; the fleeing prime minister Léon Gambetta suffered a flesh wound in the hand. And even after clearing the lines the balloons were not out of danger, for a troop of Prussian horsemen would begin pursuing them like a foxhunt. Most balloons escaped, but several were swept out to sea and lost. Some got caught in easterly winds and blew backwards into Germany, at which point all passengers, human and otherwise, were executed as spies.

Janssen knew the risks he faced as he climbed aboard La Volta in December 1870. He’d had to toughen up early in life, starting when a nurse dropped him as a baby, breaking his foot and leaving him with a permanent limp. With a musician for a father, he couldn’t afford to attend college, so he worked at a bank by day and built an observation tower on his roof to learn astronomy by night. (Which all astronomers do, obviously, but you catch my drift.) After years of drudge work, he finally landed a spot on a scientific expedition to Peru, then almost died of dysentery. Undeterred, he made more trips abroad and did pioneering work on the atmospheres of Mars and the moon. At last, the French government sent him to observe a solar eclipse in India on August 18, 1868, the most important day of his life.

The 1868 eclipse splashed down near the Red Sea and swept through Central Asia. Janssen decided to observe it with a new instrument, the spectroscope, which broke down the light of the sun in a novel way. As the song says, the sun is a mass of incandescent gas, and hot, incandescent gases have a curious property: they emit sharp bands of light. All hydrogen atoms inside stars, for example, emit one bright red line, one soothing aqua one, and a few muted purples. Other chemical elements emit their own characteristic bands. These bands normally blend together in our eyes, but the spectroscope allowed scientists to tease them apart and study them. Astronomers could therefore pick out the elements inside the sun for the first time.

In 1868 Janssen focused his spectroscope on a neglected region of the sun, its corona, which consists mainly of geysers of hot gas. The glare of the sun normally overwhelmed these Old Faithfuls, but the moon conveniently dimmed everything during an eclipse, while still leaving the corona visible. During those precious few minutes of darkness, Janssen observed hydrogen bands in the corona, as he expected. But he also noticed other lines, including a bold yellow one—one so bright it startled him. The eclipse ended before he could conclude much, but he vowed to himself, “I will see that line again.”

Unbeknownst to Janssen, the English astronomer Norman Lockyer had built his own spectroscope and had spotted that same yellow line in October 1868. (This was months after the eclipse, but Lockyer had discovered a technique for focusing his spectroscope on the sun’s rim and studying the corona during daytime.) And unlike Janssen, Lockyer never shied away from leaping to conclusions. Most turned out to be wrong, but every so often he hit on something spectacular: it was Lockyer who realized that the pyramids in Egypt weren’t just tombs, for example, but astronomical instruments as well. So as soon as Lockyer saw that bright yellow line in the corona, he decided he’d discovered a new, extraterrestrial element, which he named after the sun—helium.

To stake his claim on helium, Lockyer dashed off a paper to the French Academy of Sciences in Paris. Janssen, meanwhile, lingered over his analysis, and when he too finally sent a paper to the Academy, the slow mail service in India delayed things more. So Lockyer’s paper not only arrived first, it got translated and typeset. A friend of Lockyer’s was in fact preparing to read the paper during a meeting in late 1868, establishing Lockyer’s priority forever, when the afternoon mail arrived. An intrepid clerk fished out Janssen’s letter and sprinted up to stop the meeting. Lockyer’s backers grumbled at this: the coincidence stretched the bounds of credulity. But the two men—now instant rivals—would have to share credit for helium.

Although no one could dispute the bold yellow line, many astronomers objected to the idea of a new element inside the sun. Much more likely, they argued, this line represented a common element behaving strangely in the sun’s extreme heat. So to beef up the evidence for helium, and prove that he deserved equal credit, Janssen arranged to visit Algeria on December 22, 1870, and observe the next solar eclipse. Life then intervened in the form of Otto von Bismarck, who put Paris in a stranglehold in September, dooming Janssen’s plans.

But two unlikely saviors emerged over the next few weeks. In the spirit of fair play, Norman Lockyer spearheaded a movement to secure safe passage for Janssen to leave the city. Even more surprisingly, Bismarck agreed. Was the German chancellor a secret star-gazer? More likely, he simply wanted to win some cheap, easy points in the international community. Janssen’s snubbing the safe passage, then, embarrassed Bismarck no little amount. He promised to shoot the astronomer down, vowing that any stars Janssen saw on his balloon flight would be his last.

By December, the French had already launched dozens of balloons, most of them stitched together by dressmakers working in the idle central train station. They were awfully rickety outfits, made of cheap calico and designed to last for one flight only. To complicate matters, Janssen and his co-pilot, a sailor, had exactly 0.0 hours of flying experience between them. Janssen nevertheless limped up to the basket on December 2, climbed in, checked over his astronomical equipment, and at 6 a.m. ordered the men holding the ropes to let go.

As they shot upward in the dark, Janssen could see nothing beneath them but small hearth fires, tiny volcanoes erupting across Paris. A few minutes later, the silence was broken by the rifles of the Prussian horseman, who created their own tiny explosions of orange below. Thankfully, the gusting dawn winds pushed Janssen and his co-pilot beyond their pursuers, and the two men relaxed. But as they drifted, they realized that the dawn winds weren’t letting up. That they were, in fact, increasing—buffeting the basket and pushing them faster than expected. Pretty soon they could see the Atlantic Ocean looming. They began a desperate attempt to lower themselves, and after five hours and 225 miles, they crashed down in a field just miles short of the cold sea. They were immediately surrounded by farmers, who served the famished aeronauts their first square meal in months, a feast of roast chicken, butter, and eggs. A few days later Janssen relayed a secret message to the escaped prime minister of France—he’d been acting as a spy after all. He then raced off for Algeria.

And all for naught. After months of siege and weeks of travel, he arrived in Algeria exhausted but eager—and found the skies overcast. “Shut behind a cloud-curtain,” as one historian remarked, “more impervious than the Prussian lines.” There would be no eclipse, no observations, no yellow lines.

It’s enough to make you groan aloud. Such a lofty escape, such a deflating denouement. But Janssen took solace in two things. One, that Lockyer, in Sicily, suffered the same fate. Two, that other astronomers, at other sites, did glimpse the sun’s corona that day and confirmed his yellow helium line. And although no one knew what helium was until William Ramsey isolated it on earth in 1895, Janssen and Lockyer still get credit for its discovery today. No doubt it was Otto von Bismarck’s least favorite element.

After the disappointment with the eclipse, Janssen continued his pioneering work on the atmospheres of other planets. This work was based on the idea that, as light shines through a gas, the gas will absorb certain bands of color. Imagine a rainbow, and then imagine that someone comes along with some ink and a brush and blacks out a stripe here, a stripe there. That’s an absorption spectrum. And each element once again absorbs light in a characteristic way.

Absorption spectrums can reveal something else as well—the presence of molecules, clusters of multiple elements. Depending on its shape, every different molecule in existence absorbs light of specific colors, which allows astronomers to detect the presence of those molecules on distant planets.

Janssen was especially interested in detecting water on other planets. So he made a 121-foot-long tube, filled it with steam, and began shining white light through it, until he knew exactly what colors disappeared when water vapor was present. He then limped to the top of Mt. Etna in the late 1860s and the Himalayas in the early 1870s and examined the spectrums of the moon and Mars. The moon seemed like a planetary desert, with no water whatsoever. Mars, though, Mars looked different. Mars seemed to have traces of water. And after he checked this work against the 121-foot tube, Janssen made a leap worthy of Lockyer. Mars, he announced, was humid. Mars had water. It was the most spectacular discovery Janssen would ever make.

It was also bogus. Mars has not had water vapor in its skies for billions of years, and no one quite knows how Janssen concluded otherwise. Maybe he confused water’s signature with that of another, similar gas. Maybe some random mist in both Italy and Nepal bollixed his readings. Maybe he was simply human, and saw what he wanted to see deep down.

Regardless, this is one of those false “discoveries” in the history of science that, while wrong, ended up pushing science forward. However misleading in its details, Janssen’s work enlivened the imagination of astronomers worldwide, and set off a fury of speculation about the atmospheres of other planets, work that continues today. Of course, what astronomers really wanted to know was what the atmospheres of those distant planets implied about their habitats—including whether they harbored life. And even today, gases remain the best clue available for judging the prospects for life on other planets. More uncomfortably, those distant atmospheres are the only clues we humans have for determining where we might find refuge someday if we succeed in destroying our own air—a decision we may face sooner than we expect.

Interlude 6a

The Reason for Coal

England invested so much money in coal-gas lighting in the early 1800s in part because England had destroyed many of its forests in previous centuries, and therefore relied far more heavily on coal than other European countries did.

chapter seven

Other Poisons

Milk, cottage cheese, eggs, and leafy green vegetables proved the most contaminated foodstuffs during the time of heavy nuclear testing, but they were hardly the only items that scientists monitored worldwide. The Saturday Evening Post gave the following partial list: “cucumbers and string beans from Thailand, hazelnuts from Sicily, cinnamon and yellow hens’ eggs from China, tea from India, wheat from Syria, the Congo, and Minnesota, cheeses from Denmark, Jordan , and Tanganyika, rhubarb and Brussels sprouts from Schleswig-Holstein, red perch from the North Sea, buffalo bones from Ceylon, human bones from many places, baby teeth from St. Louis, and reindeer bones from Little Delta, Alaska.” The story then added that “reindeer bones, by the way, had an unusually high strontinum-90 content.”

Xenotransplantation

The fact that pigs have human-like organs also makes them good candidates for xenotransplantation, wherein doctors grow human-compatible organs inside other species, with an eye toward using them in donations.

Not So Able

With the Able test, no one quite knows why the bombers missed the bright-orange target ship so badly, but the man who dropped the atomic bomb on Hiroshima, Fred Tibbets, has a theory: because he wasn’t involved. In his autobiography Tibbets claimed that he got squeezed out of the Bikini run by colleagues, who envied his fame and skill. Before the Bikini run, the military held a dive-bombing competition in New Mexico, with the winner getting the honor of the Bikini drop. Tibbets says his team won, dropping their bombs an average of just three hundred feet from the targets. But a general stepped in and had the judges throw in a fudge factor called “ballistic winds,” supposedly to take into account the gales over the South Pacific. Under these new rules, Tibbets’s team ended up last.

The winning then proceeded to prove their incompetence by fouling up a training run—not only tearing the tail off their B-29 but killing a colleague named David Semple in the process. (Semple soon became the Dave of Dave’s Dream, the plane that dropped the Able bomb.) Tibbets also claims that he caught an error in the bombing team’s calculations on the morning of the Bikini drop, but the team refused to change their numbers. In all, Tibbets says he wasn’t surprised they missed so badly.

Uranium Gas

Again, to make an atomic bomb, scientists had to isolate uranium-235 atoms from uranium-238 atoms, which in turn required converting this metal into a gas, since gases are the only state of matter where the atoms have enough freedom to separate themselves. And the easiest uranium gas to make—just mix some uranium yellowcake with nitric acid and hydrofluoric acid—was uranium hexafluoride, UF6. Manhattan Project scientists called this gas “hex” for short—which was fitting, since it was a cursed gas, so aggressive that it made even some of Fritz Haber’s chemical weapons look like pussycats. Hex reacts with water, with rubber, with grease—it even chews through solder. Manhattan Project scientists had to invent Teflon just to keep some sensitive pieces of equipment safe from hex; otherwise it would have destroyed everything in its vicinity.

Paris Is for Rays

Cosmic rays were first discovered atop the Eiffel Tower. Before 1909, scientists believed that only special atoms like uranium could produce radioactivity. But that year, a French scientist climbed the Eiffel tower with a radiation detector and heard it clicking like crazy. Scientists assumed the activity must be coming from the sun, but they found the same readings during an eclipse, and could only conclude that these mysterious new rays were somehow coming froooom spaaaaaaaace. Scientists now know that cosmic rays consist mostly of protons and other atomic fragments that originate in distant stars, perhaps supernovae. The Earth’s magnetic field shields us from the brunt of them, but several Apollo astronauts (who left the shelter of our magnetic field) reported seeing fictitious streaks of light as the rays struck their retinas and excited rods and cones there.

Radioactive Neurons

You’ve probably heard about carbon-14 in the context of carbon dating, a process that archaeologists use to date organic remains. But the addition of carbon-14 to the atmosphere in the 1950s and 1960s had an unexpected side benefit for another branch of science.

Neuroscientists have been sparring for decades over whether the adult brain can grow new neurons. Several studies suggested yes, but those opposed to the idea always picked the experiments apart, and the matter remained controversial—until a few scientists in Sweden realized that radioactivity could clear the matter up. Imagine someone born in 1930. As her body developed, her liver and spleen and other organs would have used mostly regular carbon atoms to build and repair those tissues, because regular carbon atoms are much more common. But as soon as radioactive testing started, the level of carbon-14 in those organs would have jumped dramatically. The question was whether this same thing happened in the brain. According to traditional thinking, no, since the brain didn’t make new cells. But once scientists started looking, they discovered that brain cells were just as radioactive as liver and spleen cells were. And because our 1930 baby was born before atmospheric testing began, these carbon-14-rich neurons had to have been born in her adulthood. QED.

Oddly, though, the human brain appears to make new neurons only in one area, the hippocampus. This contrasts with most adult mammals, who make new neurons in both the hippocampus and the olfactory bulb (i.e., the smell center). Overall, it seems that adult humans make around 1,400 new hippocampal neurons every day, and this activity continues at least until the fifth decade of life, perhaps longer. Unfortunately, roughly that many neurons also die every day, so we don’t come out ahead.

Discrediting Lucky Dragon

The Japanese tuna fisherman aboard the Lucky Dragon got blasted with even stronger radiation than the islanders did, both because they were closer to the epicenter and because they got caught in strong winds coming from the bomb site, with radioactive “snow” falling so thick over their boat that they left footprints as they walked. The snow also contaminated their food and cigarettes, and they ingested even more radioactivity when they consumed them.

Adding insult to injury, the United States then accused the fishermen of being Communist spies intent on stealing U.S. nuclear secrets. U.S. officials also claimed at various times that the fishermen really weren’t suffering as badly as everyone was claiming—and that if they were getting sick and dying, it was their own fault, since they’d trespassed into the forbidden zone around Bikini. (As the U.S. government well knew, this wasn’t true; the boat was actually fourteen miles outside the zone.) When Japan protested—calling the accusations “outrageous and insulting”—U.S. officials assured the world that the Japanese were just overly “sensitive” about nuclear weapons, given Hiroshima and Nagasaki and all that. (You don’t say.) In sum, U.S. officials were so paranoid about the prestige of their nuclear weapon program that they were willing to lie out of every orifice to discredit, downplay, or dismiss any political fallout from Bravo.

chapter eight

Storm King Consolation Prize

The U.S. government never took up the Storm King’s plans to regulate rainfall over the east coast by starting huge forest fires in Appalachia, but in the mid-1800s it did set up a series of weather stations across the vast, unorganized middle of the continent. (To justify the venture financially, weather rangers also agreed to keep an eye out for locusts and Indians.) The spread of telegraph lines between the stations then allowed meteorologists to collect weather reports from several locations at once and see larger weather patterns for the first time.

When to Cut Your Hair

Fun fact: depending on the humidity, your hair can shrink or stretch by as much as two percent. So if you’re looking to get the most bang for your buck in the barber’s chair, wait until it’s wretchedly humid outside before you go, since your hair will be longest then.

The Shape of Raindrops

Incidentally, raindrops aren’t shaped like might you think, like a classic teardrop. Tiny raindrops are spherical. And as drops grow larger and the air pressure on them increases, they become flatter, more like a hamburger bun.

Langmuir’s Boast

Irving Langmuir once bragged that his cloud-seeding experiments could release more energy per ounce of starting material than nuclear weapons could. That is, while it took several pounds of plutonium to make a nuke, he could supposedly wring the same amount of energy from a storm cloud with 1/1000th of an ounce of silver iodide.

Hit ‘Em Where It Hurts

The Savannah debacle in 1947 killed off most interest in weather control in the United States, but the brutal hurricane seasons of 1954 and 1955—including Hurricane Hazel, which caused $308 million in damage (almost $3 billion today) and sent 98-mph winds whipping through Washington, D.C.—helped convince several landlubbers in Congress to resurrect weather modification programs.

Sky-Embossing

The pilots for Project Cirrus practiced their seeding skills on sheet clouds several miles wide, and they found the work a blast. It was like inverse sky-writing. That is, rather than leave puffs of white behind them, the chemicals they dumped would carve letters and shapes into clouds—reverse-embossing them with giant L’s and ovals and Greek letters. It sure beat the bombing runs they’d been training for before.

Meddlesome Monks

In addition to washing out roads and bridges, the officials in charge of Project Popeye hoped that dumping rain on southeast Asia would help disperse crowds of Buddhist monks, whose constant protests were becoming a real public-relations problem. The monks would sit placidly through most attempts to break them up, even tolerating tear gas. But they tended to run inside and hide during rainstorms.

Quotes on Rainmaking

Here are two of my favorite quotes from the annals of rainmaking, one ridiculous, one scary. In one case, scientists were arguing that rainmaking really does work. They added, however, that “why some experiments yielded increases [in rainfall] while others decreases in rainfall is not known.” That kills me. The obvious answer, of course, is that the experiments weren’t doing anything. Indeed, their own words give the game up: they basically admit that there was no correlation between doing an experiment and an increase or decrease in rainfall. It’s a little like me claiming that I really can control coin flips with my mind—then admitting I’m not sure why I sometimes get more heads and sometimes more tails. It’s because I’m not actually influencing anything.

The other quote involves the major lesson that the military drew from Project Popeye. Even though they got no new weapons from their research, and few real insights into weather science, they did make the important discovery that “one can conduct covert operations using a new technology in a democracy without the knowledge of the people.” Yikes.

Richardson’s Obsession

Lewis Fry Richardson, who dreamed up the grandiose, stadium-sized weather forecasting center mentioned in the book, had an interesting reason for volunteering for war service. As a Quaker and pacifist, he declared himself a conscientious objector to all war in the early 1900s. In fact, he was so opposed to military work that he resigned from the British Meteorological Office when the British military took it over in 1910. But when World War One broke out, he said found that his “intense objection to killing people” was overridden by “an intense curiosity to see war at close quarters,” and off he ran to France.

As an ambulance driver Richardson treated not only French and British soldiers, but German prisoners of war. It was considered the decent thing to do. That said, Richardson did subject the prisoners to some abuse: an idealist through and through, he insisted on trying to teach them Esperanto in the hospitals, and would not let up no matter how much they begged him to stop. (Such treatment is now outlawed by article 3.14.159 of the Geneva Conventions.)

First Satellite

The drum-shaped weather satellite TIROS, launched in 1960, became the first spacecraft to send pictures back to Earth. It was 42 inches in diameter, 19 inches high, and weighed 270 lbs., mostly aluminum and stainless steel. It had 9,200 solar panels to power it. Before the debut of satellites, meteorologists had to send planes out looking for hurricanes—there was no other reliable way to find them.

Interlude 8a

Speed of Sound

Sound travels fast in air (772 miles per hour at 72°F), but it travels faster still in liquids like water, since the molecules relaying the message have much less distance to travel before they knock into their neighbors. Sounds zip along at even faster speeds in close-packed solids, reaching 7,200 m.p.h. in gold, and 27,000 m.p.h. in diamond. For some perspective, light in a vacuum travels at roughly 180,000 miles per second.

chapter nine

Martian Civilization

In addition to his books and newspaper articles on Mars and its extensive “canal system,” Percival Lowell also started a popular lecture series on Martian civilization. One newspaper wrote of the events that “the streets nearby were filled with carriages, as if it were grand opera night.”

Absorption and Emission

Again, light-emission spectrums show single, discrete lines of color at certain points, while light-absorption spectrums have single, discrete lines of color missing from certain points. And as you might have guessed, the places that the lines go missing in an absorption spectrum are the same places where the lines appear in emission spectrums. They’re kind of like photograph negatives in that way, and if overlaid onto each other, they would produce a perfect rainbow with no gaps.

The full explanation of why gas molecules absorb and emit light requires quantum mechanics: basically, when electrons orbiting the nucleus of an atom absorb light, they jump to higher energy levels. When those electrons lose this energy and drop back from the excited state to the ground state, they emit photons of light. And because electrons can jump only between well-defined energy levels, they can absorb and emit only specific colors of light.

Where CO2 Comes From

It follows like night from day that, as carbon dioxide levels rise worldwide, oxygen levels must necessarily decrease. Why? Because the two O’s in CO2 have to come from somewhere, and O2 is that somewhere. Mind you, we won’t actually run out of O2 (not even close), but it’s still disconcerting.

In case you’re wondering, the following countries emit the most CO2 each year: China (28 percent of the world’s total), the United States (14 percent), the European Union (10 percent), and India (7 percent). As for the activities that produce CO2, it breaks down as follows: burning coal (43 percent of the total), burning oil (33 percent), burning natural gas (18 percent), and making cement, of all things (5.5 percent).

Bad Joke

The idea of spewing sulfur into the upper atmosphere to cool the planet started with a Dutch scientist named Paul Crutzen, who won the Nobel prize for his work on ozone. He later said he proposed the idea to shock world leaders, and goad them into curbing the emission of greenhouse gases. But politicians aren’t known for their sense of shame, and several of them welcomed Crutzen’s suggestion as an escape hatch—a way to mitigate the worst effects of climate change without having to make any difficult choices. Indeed, this is exactly why some people worry about geoengineering: as an economist would say, it has a large “moral hazard” attached to it.

The Dream of Tsiolkovskiy

The first person to appreciate the promise of hydrogen and oxygen as rocket fuel was Konstantin Tsiolkovskiy, a deaf science teacher at a girls school in Russia, who developed the idea around 1903. He settled on the H2/O2 mix because it burns at a high temperature, and because both gases (especially hydrogen) weigh so little, which allows the exhaust to come screaming out the backside at high speeds. This velocity in turn produces the biggest push of momentum, which is the vital thing for making rockets go. NASA began using Tsiolkovskiy’s recipe in rockets in 1963, and it worked every bit as well as he’d dreamed.

Air Elsewhere

I’ve heard people worry aloud that our lungs might shudder or collapse if they breathed in the oxygen on a different planet. After all, wouldn’t the gas be somehow different there? In truth, there’s nothing to worry about. Oxygen is oxygen is oxygen—an atom here is the same as an atom anywhere in the universe, and the same goes for every other element.

The rules change a little, though, when atoms start combining into molecules. As anyone who has ever taken organic chemistry probably remembers, most biochemicals come in several varieties. These sometimes include mirror images of each other—a “right-handed” and “left-handed” version of the same basic structure. And if we tried to eat food made of proteins or sugars of the “wrong” handedness, our bodies would starve, unable to digest them. But oxygen gas is simple, just two atoms yoked together, so our cells can handle it. Same with water and even booze—you’d get just as drunk at the Mos Eisley Cantina as you would at the watering hole down the street from your place right now.