Elemental

by Tim James

  Right, on with the list.

  ELEMENT OF AGES

  Carbon is an obvious choice to kick things off. It’s so vital to our world it’s practically humdrum. Look around the room and probably 90 percent of things you’re looking at are either made from, extracted with, or powered by carbon. It is the element that has defined the ages of humankind.

  We’ve been around for hundreds of thousands of years, but what we call civilization began with manipulating metals. The Stone Age represented the primitive infancy of our species but it was the Bronze and Iron Ages that were the turning points.

  Before we mastered the art of metallurgy, the only metals we knew about were gold and occasionally silver, so all our construction materials, weapons, and tools came from bashing rocks together. Then at some point between 8000 BCE and 3000 BCE everything changed.

  Most metals in nature are bonded to oxygen, but oxygen forms better bonds with carbon. This means if we mix enough carbon together with our metal oxide (rock) and give the whole thing some energy (heat it), everything rearranges to carbon dioxide and pure metal. This technique, known as smelting, was the most important chemical reaction since fire itself.

  The early technologists, whoever they were, discovered that roasting rocks in the presence of charcoal produced metal. First, we began extracting copper and tin, giving us bronze. Then we learned how to get the fires hotter and started extracting iron, previously only found in meteorites.

  By the nineteenth century we were burning carbon itself as a fuel source, using it to run our combustion engines. Carbon has an advantage over other fuels because, rather than leaving unpleasant residues, it burns away to an invisible gas. Where’s the harm in that?

  Today, we still use coal for our power stations, so the electricity you use is most likely down to carbon too. It’s only in the past sixty years we’ve realized that all that CO2 has the awkward feature of absorbing infrared radiation, slowly heating the atmosphere as the decades tick by.

  On the plus side, carbon is also the basis of polymer chemistry. Take a long chain of carbon atoms, use hydrogen to make sure each one has the correct number of bonds, and if you tangle the ropey chains together you end up with a plastic.

  Imagine a world without plastic, metal, or widespread electricity and you begin to see why carbon is so important.

  Carbon’s versatility is a result of its location on the periodic table. It sits on the top row, making it a small atom capable of forming tight bonds, in the fourth column along, giving it four available bonding electrons.

  An element like fluorine is also on the top row but it is only one electron away from a filled shell, meaning it will form one bond and then stop. Carbon has four electron spaces, meaning it can form four links to other atoms, all of them strong.

  Other elements that form multiple bonds are usually too big for the bonds to be robust, so carbon has the best of both worlds, which is why we find it in everything from our cell membranes to our cell phones.

  It gave us the materials we use and the power to manipulate them, and now its presence in the air is threatening to knock our climate out of equilibrium. If there is one element that has turned the course of human history more than any other, it’s carbon.

  FOOD FOR AN EMPIRE

  At the start of the 1800s Britain’s armies were expanding across the globe. The Napoleonic wars were finishing, slavery was coming to an end, and the Empire was approaching its “golden age.” But the admirals and generals of this ruthless military machine were facing a problem. An empire is only as strong as its food supply. How do you get food to thousands of people, far away from where it’s being produced?

  The answer was discovered by a French inventor named Philippe de Girard who devised a method to vacuum-seal food in a tin can. After testing his invention on several British scientists, the idea was sold to the engineer Bryan Donkin who set about improving the method.

  Donkin was already a superb craftsman who consulted on the manufacture of Babbage’s difference engine and Telford’s suspension bridge, and was also the inventor of the humble pen. While the inventor of the pen is sometimes misattributed to John Loud in 1888, Donkin already had a patent in 1803.4 Let’s just get our pen history right, folks.

  By 1813, Donkin had designed a method to mold tin cans in such a way that food inside would be locked in without any air, meaning it could last for years and be transported as far as was needed.

  After Queen Charlotte sampled a tin of his corned beef and praised the taste, Donkin began manufacturing tin cans en masse and sold them to the Navy. Tin cans allowed countries to feed their armies during both world wars and today over forty billion are sold around the world annually.5 While many of these cans are made from steel today, it’s the tin plating that prevents irreversible rust.

  What also makes tin special is not what it does as a pure metal, but how it can modify other metals when they are mixed together, forming what’s called an “alloy.”

  Its softness is one of the reasons it is mixed with copper to make bronze. When alloyed with lead it forms pewter, the material most cutlery was made of until very recently. When mixed with a bit more lead you end up with solder, the “glue” used in electronics to join wires.

  Bell metal, used for making bells, is an alloy of tin with copper. Gunmetal used for making, well, guns, is an alloy of tin with copper and zinc. Terne, used to make roofing, is tin mixed with lead again. Ball bearings are usually made from tin with copper and iron. Galinstan, used for telescopes, is tin mixed with gallium and indium, and the list goes on. Tin is the great modifier of the periodic table.

  It’s not quite as prevalent as iron but it has the clear advantage of being rustproof and, because it’s easily extracted and manipulated, anyone can work with it from the richest monarch to the lowliest commoner. While armies and politicians might have prized elements like gold, tin has always been the element of the people. Not that gold hasn’t been important, too, mind you.

  ALL THAT GLITTERS

  The color of gold has led many cultures throughout history to worship it, often associating it with the sun (silver being linked to the moon). It arises because gold has large gaps between the atomic orbitals, so visible light loses a lot of energy when it strikes. The highest energy colors like violet, blue, and green are absorbed into the metallic surface while the yellows and oranges are bounced back out. Cesium and copper also have yellow/orange hues, but nothing compares to gold.

  As we saw in Chapter 3, gold was essential to discovering the nucleus and therefore modern chemistry itself. It was used because it’s the most malleable metal available, so soft that 28 g would be enough to make a wire stretching nine times the height of Everest.6

  This ease in molding, as well as its shine, has also led to its use in jewelry since prehistory, not to mention the fact it doesn’t tarnish. While other metals will gradually react with oxygen, gold will gleam forever.

  It’s also a very rare metal. If you were to collect all the gold deposits in the world it would total around 170,000 tons. That would barely fill three Olympic-size swimming pools.7

  This combination of malleability, rarity, permanence, and beauty are what make it so precious. Gold can be traded anywhere in the world, regardless of local custom, because everyone values it.

  In Finland the skins of squirrels used to be acceptable as money, and up until the twentieth century Ethiopia used blocks of salt.8 Money is different wherever you go, but gold is revered everywhere and always has been, making it the only true international currency.

  Alexander the Great led the Greek army to conquer the Persian Empire—the largest in the world—in order to steal their gold. Julius Caesar did the same thing to western Europe. So did King Ferdinand of Spain, sending his conquistadors to rip gold from the Americas (and we all know how that story turned out).

  The first gold coins were used in China during the sixth century BCE, but by the 1800s every large country in the world (apart from China, ironically) was usin
g a gold standard for international as well as domestic business.

  Owing to its rarity and weight, though, gold coins are far from practical so banks began printing contracts that corresponded to a certain amount of solid gold. This was the invention of modern money itself.

  KNOWLEDGE AND POWER

  Some of the elements have a split personality. The same substance can be of great benefit to the world, but also the cause of endless pain. No other element can lay claim to having enlightened so many or killed so many as lead.

  Once extracted from its ore, lead is a dull metal with three important properties: density, meaning it’s hard to break, malleability, meaning it can be bent, and corrosion resistance, meaning you can have it in contact with water.

  The Romans carried out lead mining on a grand scale because they used it for pipes and waterworks. Iron is no good because it rusts so lead was used at a rate of thousands of tons per year. The very notion of water straight to people’s homes hadn’t been explored properly until the Roman plumbing system. Even the word plumber comes from the Latin word for lead, plumbum, because piping specialists were plumbum experts. That’s why it has a silent “b.”

  Because of its toxicity, some people have speculated that leadpoisoning contributed to the decline and ultimate defeat of the Roman Empire.9 This seems unlikely, however, as lead poisoning was already a known malady and water doesn’t usually dissolve enough to reach dangerous levels.10

  It’s possible that boiling grape juice in huge lead vats may have caused lead poisoning in some of the aristocracy, but this is speculation at best. It’s unlikely that lead caused the collapse of Roman civilization, but don’t worry, it’s still responsible for millions of deaths every year.

  In thirteenth-century China, it was realized that a small tube of gunpowder could launch a projectile at high velocity when it exploded—the invention of the gun. The technology spread to European armies and the best metal for making bullets turned out to be lead—not only because it’s readily available and easy to manipulate, but because it is so dense that once it is fired from the barrel it keeps going in a straight line. No other metal allows us to shape it so well while being dense enough to hold its trajectory.

  Nobody knows how many bullets are manufactured in the world today but the number is probably in excess of ten billion a year: enough for one bullet per person. It’s hard to think of a weapon that has caused more death than guns firing lead bullets.

  But lead has also done wonders for us. In 1440 Johannes Gutenberg was looking to find a way of quickly conveying information to people. Up until then, every text and book had to be copied by hand. If a machine could be rigged to do the job, books could be produced in a matter of days rather than months.

  The result was his printing press, only achievable thanks to lead (alloyed with a little tin). Because lead was so malleable, it could be carved into the precise shapes of block letters. Other metals could be molded too, but lead’s density meant hammering it repeatedly onto a page wouldn’t cause it to wear away.11 The same characteristics that help lead kill are those that help it educate.

  DRINK IT DOWN

  People are living longer these days. Obviously a good thing. The only downside is that we’re more prone to age-related disease. This has led to a lot of hoo-ha and fear-mongering about the apparent rise of cancer and heart disease. I’ve heard everything blamed from GMO foods to (perversely) chemotherapy drugs themselves, but it really comes down to cold numbers.

  Humans die. Sorry to break that to you. Our bodies are fragile and they aren’t built to last. The older you get, the less you tend to function and the more likely you are to die from something like cancer or heart disease. The only reason we’ve seen an apparent rise in these deaths is because people are lasting long enough to die from them. Age-related illness has existed as long as the human body; it’s just that most people tended to extinguish before they got that far.

  Death is always unpleasant but I would say age-related illness is a fair price to pay for a life expectancy in the eighties. During the mid-1800s, life expectancy was forty-two, mainly because people died in childhood, bringing the average down.12 The only reason we enjoy a higher number today is simple. It has little to do with a gluten-free diet or a Pilates class. It’s because we have defeated the world’s number-one killers. We don’t die of infection anymore.

  In the 1340s, hundreds of millions of people died from bubonic plague. Between 1817 and 1917, an estimated thirty-eight million died from cholera.13 Measles and smallpox have been responsible for more deaths worldwide than any war you care to mention and don’t get me started on polio or malaria.14 In many parts of the globe, these diseases are still rampant, but in the West we are fortunate because we have eradicated them. Quite frankly, dying from old age is something for which we should be grateful. Many are not so lucky.

  The reason we aren’t seeing epidemics breaking out every year is down to two things: vaccination and element number 17, chlorine.

  The first widespread use of chlorine was during the First World War when the German chemist Fritz Haber introduced it as a chemical weapon. In 1915, he oversaw the installation of five thousand canisters of it along a 7-km distance at the western front and, when the wind began blowing the right way, Haber ordered the canisters be opened.

  Chlorine is a thick green gas that rolls along the ground like a liquid. Carried by the wind, the chlorine was dragged toward the British Army and flooded their trenches, asphyxiating and blinding thousands of men.

  According to Hermann Lutke, on May 1, 1915, a party was being held in Haber’s honor to praise his simple but effective use of chlorine chemistry. A few hours after the party, his wife Clara (a noted pacifist) took Haber’s service revolver into the garden and shot herself in the chest, dying moments later in her son’s arms.15 In this context, chlorine has a similar reputation to lead but, just like lead, it can be put to a far better use.

  Because it is lethal to biological organisms, if handled correctly it can be used to kill the pathogens that would otherwise be lurking in our water supplies.

  The average person in the US and the UK uses around 340 liters of water a day and it has to be clean in order to stop the spread of disease.16 Even toilet water has to be potable because if it contained anything harmful it could get airborne during flushes.

  There are a few alternatives to chlorination, such as bubbling ozone through the water, but chlorine is the main choice for every European country and the whole of the United States.

  It works because chlorine dissolves to form hypochlorous acid, HOCl, which is lethal. That’s what kills you if you are unfortunate enough to inhale it as a gas. It’s easy to remove from water, though, so if we pump it into our drinking supply it will kill everything, after which we remove the excess with carbon charcoal.

  While adding fluoride to the water has caused controversy (largely because it was implemented before long-term studies were finished), nobody objects to chlorine. It’s the main reason you aren’t currently dead.

  THE SILVER SCREEN

  Any writer of non-fiction, no matter how objective they claim to be, will be writing with bias, putting their own personal views into things, often without realizing it. And by the way, don’t you just hate celery? Almost all of recorded history has been the result of eyewitness accounts and people’s memories, which makes things hard to verify.

  That changed in 1717 when a German chemist named Johann Schulze left a bottle of silver nitrate and chalk on his windowsill. Schulze placed the bottle down absentmindedly and, when he picked it up a few minutes later, was shocked to find it had turned brown. Except for a thin white line suspended in the liquid.17

  He looked out the window to see what could have reacted with his solution and noticed a piece of thread hanging across the window in exactly the same shape as the white line inside the bottle.

  Where the sunlight hit the silver nitrate it made it go dark, but where something had obscured the sun, the liquid remain
ed white. Schulze had taken the very first photograph and it was a liquid. Considering Henri Becquerel’s radioactivity discovery, it’s strange how many times leaving a jar lying around has led to a monumental realization.

  Silver atoms can be bonded to nitrate molecules in solution, but given a bit of energy they can separate and form solid metal. A lump of solid silver glistens brilliantly but powdered silver is a dark brown, showing exactly where the light has hit it.

  It was a French inventor named Joseph “Nicéphore” Niépce who realized that putting silver compounds onto a piece of paper and focusing images with a pinhole camera would create a black-and-white copy of what was being projected. In 1829 he used this technique to capture the world’s first proper photograph from his bedroom window, View from the Window at Le Gras, taking eight hours of exposure time.

  At least, that’s the official story. In 1777, another scientist had already discovered that you could trap silver-solution images on a piece of card using ammonia. This scientist also figured out the cause of the phenomenon but never pursued the research, denying himself the title of being the inventor of photography. That scientist (and I’m not making this up) was none other than Carl Scheele.

  Over the following century we discovered other silver chemicals that reacted faster than nitrate and, by using lenses, we were able to intensify the light, creating instantaneous images of particular moments. We didn’t have to rely on word-of-mouth or written accounts to store information anymore: silver allowed us to capture pictures of things as they truly were.

  Historians disagree over who took the idea of photographs and strung them into movie reels, but the patent for the first film camera seems to have been filed by one Wordsworth Donisthorpe in 1876.18 He used it to film a few seconds of Trafalgar Square and started the movie industry, which we still call “the silver screen” after the element involved.