• Emily Rose Seeber

Primo Levi's The Periodic Table


At Science Live! with the Block 4s (Year 10), the chemist Andrea Sella reminded me about a book, one I read when I was about 16, in which the Italian chemist, Primo Levi, relays short stories about his life, linking each segment to an element on the Periodic Table. I remembered the book as being deeply moving; far more than the exposition about the elements that I had expected.

In this assembly, I’m going to take you through some of the ‘elements’ in Levi’s life, to find out what the elements can teach us.

Firstly, hydrogen. At this point in his life, in 1935, Levi was 16 years old. He was living in Turin, Italy where he had grown up, and where he lived for almost all of his life. Levi was a gifted scholar in all areas, but he was defined by his curiosity about the world around him; he was fascinated by matter; he was going to become a chemist.

His friend Enrico had stolen the keys to his older brother’s basic laboratory, and the pair snuck in to do some experiments. They ended up electrolysing some water.

"I put some water in a beaker, dissolved a pinch of salt in it, turned two empty jam jars upside down in the beaker; then found two rubber-coated copper wires, attached them to the battery’s poles, and fitted the wire ends into the jam jars. A minuscule procession of a bubbles rose from the wire ends: indeed, observing them closely you can see that from the cathode about twice as much gas was being liberated as from the anode. I wrote the well-known equation on the blackboard, and explained to Enrico that's what was written there was actually taking place. But Enrico was in a bad mood and doubted everything. "Who says that it's actually hydrogen and oxygen?’ he said to me rudely. "And what if there’s chlorine? Didn't you put in salt?’

"The objection struck me as insulting: how did Enrico dare contradict my statement? ‘Now we shall see,’ I said: I carefully lifted the cathode jar and, holding it with its open end down, lit a match and bought it close. There was an explosion, small but sharp and angry, the jar burst into splinters (luckily, I was holding it level with my chest and not higher), and there remained in my hand, as a sarcastic symbol, the glass ring of the bottom.

"We left, discussing what had occurred. My legs were shaking a bit; I experienced retrospective fear and at the same time a kind of foolish pride, by having confirmed a hypothesis and having unleashed a force of nature. It was indeed hydrogen, therefore: the same element that burns in the sun and stars, and from whose condensation the universes are formed in eternal silence."

Now we turn to the element potassium. Most of you will have seen potassium reacting with water, and be able to describe its chemical and physical properties in some detail. But here it is in a large quantity just for fun.

Levi did go to university to become a chemist. He passed the exams to start a year early, which was fortunate, because in October 1938 the Italian Racial Laws, discriminating against Jews, came into effect. Levi, who had already started at university was allowed to finish, but new Jewish students were not allowed to enrol. If he had not been ahead of his peers, he would have been unable to go.

Even so, he did not have an easy time. He was seen as different. He remarked later in life that the discrimination he experienced made him feel ‘like a Jew’, which was something he had never really felt before. Because of his heritage, he struggled to get a supervisor for his dissertation. He eventually ended up working for ‘the assistant’; an assistant professor in astrophysics who lectured him in his third year. He was tasked with purifying organic liquids enough so that the physicists at the Institute of Experimental Physics in Turin could compare the polarities of the liquids and see whether or not they were governed by the same laws as dilute solutions.

Molecules in many liquids have a dipole, this means they have a slightly positive charge on one side (due to a lack of electrons), and a slightly negative charge on the other end (due to the gathered electrons). Molecules which have a dipole are attracted in an electric field. You have probably seen the experiment before in which you hold a charged rod next to a stream of water, and the stream of water is bent towards the rod.

So, Levi set out purifying a range of organic liquids, including benzene, which is a ring of six carbon atoms surrounded by a ring of six hydrogen atoms. He distilled the 95% pure solution he started with once with great success. But the solution was still not pure enough.

"Now I had to distil a second time in the presence of sodium. I ransacked the entrails of the Institute in vain: like Ariosto’s Astolpho on the Moon I found dozens of labelled ampules, hundreds of abstruse compounds, other vague anonymous sentiments apparently untouched for generations, but not a sign of sodium. Instead I found a small vial of potassium: potassium is sodium is twin, so I grabbed it and returned to my hermitage."

So Levi put a pea-sized piece of potassium into the round bottomed flask with the benzene he was distilling, and carried out his distillation. After it was finished, he dutifully, in recognition of the viciousness of the element, speared it with a needle on a stick to remove it, wrapped the pea in paper and went and buried it outside in the courtyard.

When he came back, like a responsible chemist, he started to do the washing up. But when he went to wash up the round bottomed flask, it shattered directing a flash of flame at the window, the curtains caught fire, and the room filled with smoke. Levi tore down the curtains while choking to extinguish the fire. This wasn’t the washing up experience that Levi had anticipated. He approached the assistant, who reminded him that something must have been left in the flask, otherwise it would not have caught fire.

"I returned to the scene of the accident, and found fragments of the flask still on the floor: on one of them, by looking closely, one could see, barely visible, a tiny white fleck. I tested it with phenolphthalein: it was basic, it was potassium hydroxide. The guilty party had been found: adhering to the glass of the flask there must have remained a minuscule particle of potassium, all that was needed to react with the water I had poured in and set fire to the benzene vapours.

"The assistant looked at me with an amused, vaguely ironic expression: better not to do than to do, better to mediate than to act, better his astrophysics, the threshold of the Unknowable, than my chemistry, a mess compounded of stenches, explosions, and small futile mysteries. I thought of another moral, more down-to-earth and concrete, and I believe that every militant chemist can confirm it: that one must distrust the almost-the-same (sodium is almost the same as potassium, but with sodium nothing would have happened), the practically identical, the approximate, the or-even, all surrogates, and all patchwork. The differences can be small, but they can lead to radically different consequences, like a rail road’s switch points; the chemists trade consists in good parts in being aware of these differences, knowing them close up, and for seeing their effects. And not only the chemist’s trade."

Levi gained his degree in 1941, with top marks, having submitted three dissertations. However, his degree certificate stated the following ‘Primo Levi, of the Jewish race, had been conferred a degree in chemistry summa cum laude’. This essentially made it worthless in Facist Italy at that time. He struggled to find work as a chemist, and eventually labored in an asbestos mine extracting nickel from the waste materials under a non-existent identity.

Gold.

In September 1943, after the fall of Mussolini, Nazi troops moved in to occupy Italy. The rounding up of Italian Jews began. An estimated 7,500 thousand Italian Jews became victims of the Holocaust.

At this point, Levi and his intellectual Jewish friends scattered into the winds, many of them fled to join partisan groups in the mountains.

"We were cold and hungry, we were the most disarmed partisans in the Piedmont, and probably also the most unprepared. We thought we were saved because we had not yet moved out of a refugee buried under 3 feet of snow: but somebody betrayed us, and on the dawn of December 13, 1943, we woke surrounded by the fascist republic: they were 300 and we 11, equipped with a Tommy gun without bullets and a few pistols. As they came in I managed to hide in the stove’s ashes the revolver I kept under my pillow, and which in any case I was not sure I knew how to use: it was tiny, all inlaid with mother-of-pearl, the kind used the movies by ladies desperately intent on committing suicide."

Once taken away, Levi was questioned and threatened. He was told that he would either be labelled as a partisan and taken out and shot against the wall, or labelled as a Jew, in which case he would be taken to a collection camp. He admitted to being a Jew.

Why is this episode called gold?

While Levi is waiting to be taken to the collection camp, he meets another prisoner, who’s family have been panning for gold on the same stretch of the Dora for generations. When he is taken back to his cell he reflects:

"In the cell I was welcomed by the solitude, the freezing pure breath of the mountains which came through the small window, and the anguish of tomorrow. I listened - in the silence of curfew one could hear the murmur of the Dora, lost friend, and all friends were lost, and youth and joy, and perhaps life: it flowed close by but indifferent, dragging along the gold in its womb of melted ice."

Gold is an extremely unreactive element, it undergoes very few chemical reactions, and none that occur in nature. Levi’s arrest had no effect on gold. The war flooding through Europe had no effect on gold. The mass extermination of whole peoples had no effect on gold. Gold is unchanging. It is indifferent.

Levi worked with cerium in his final months in Auschwitz. He was one of only 20 Italian Jews in his shipment of 650 to survive the final 11 months of the death camp.

Levi approached life in Auschwitz as a chemist. He made observations, learned the rules, the layout, the geography. He also realised early on that he would need to learn how to speak German, so he did that. It seems from his writing that he maintained a kind of emotional distance from his experiences.

But while he was inside Auschwitz, Levi’s qualifications as a chemist allowed him to escape the hard manual labour in the winter, as he was accepted to work in the laboratory instead. While others died in the cold outside, he survived.

"We were not normal because we were hungry. To eat, to get something to eat, was our main stimulus, behind which, at a greater distance, followed all the other problems of survival, and even still father away the memories of home and very fear of death.

"I had made various attempts in the lab. I had stolen a few hundred grams of fatty acids, laboriously obtained by the oxidation of paraffin from some colleagues of mine on the other side of the barrier: I had eaten half of it and it really took the edge of my hunger, but it had such a nasty taste that I gave up the idea of selling the reminder. I had tried to make fritters with sanitary cotton, which I pressed against an electric hot plate; they had a vague taste of burnt sugar, but they looked so awful that I did not consider the marketable. I also forced myself to ingest and digest glycerin, basing myself on the simplistic reasoning that, since it is a product of the splitting of fats, it must after all in someway be metabolised and furnish calories: and perhaps it did furnish them, but at the cost of extremely unpleasant side-effects."

So, at this point in our tale Primo Levi is desperately looking for something that he can sell to buy food to survive.

Cerium is a lanthanide, one of the metals left off of periodic tables used at IGCSE. It is soft enough to be cut with a knife, and is silvery white. It was discovered in 1801, the same year as the asteroid Ceres, from which it gets its name. And Levi chanced upon an iron-cerium alloy in the lab formed into little rods, which could be used to make the flints for cigarette lighters.

"While our companions slept, we worked with the knife, night after night. The scene was so sad you could weep: a single electric light bulb weakly lit the large wooden hut, and in the shadows, as in a vast cave, the faces of other men were visible, wracked by sleep and dreams: tinged with death, they worked their jaws furiously, dreaming of eating. Many of them had an arm or a naked, skeletal foot hanging over the side of the bunk, others moaned or talked in their sleep.

"But we two were alive and did not give way to sleep. We worked for three nights: nothing happened, nobody noticed our activity, nor did the blanket or pallet catch fire, and this is how we won the bread which kept us alive until the arrival of the Russians and how we comforted each other in the trust and friendship which united us."

Levi returned to Turin after Auschwitz. It took him a long time to walk there, he was one of the millions of displaced people wondering the roads of Europe. And he became an industrial chemist, got married and had children. Despite his academic promise, Levi never had the opportunity to become an scholar and pioneer in the field of Chemistry: his Jewishness had prevented it before the war, and his need for an income prevented it afterwards.

Levi wrote about his experiences in the death camp in his first book If This Is a Man which was published in 1947. It did not sell well initially. People were not ready to hear about what happened in the death camps. Denial of the Holocaust was rife in Italy as ordinary people struggled with their guilt.

Years later, Levi was working in a paint and varnish factory as an industrial chemist, when he had the opportunity to speak to one of the German chemists he had met at Auschwitz. His company were having trouble with their German suppliers of a vanadium compound, and he recognised the name and poor chemical pronunciation of the chemist, Dr Müller. They began a private correspondence about their experiences in the lab at Auschwitz. They had met three times, and on the second, Müller had given him permission to shave on a Thursday as well as a Monday.

Neither his nor Müller’s memories of their meetings matched up. Levi struggled to forgive the complicated, sympathetic, flawed man he was in correspondence with.

A pity, he was not a perfect German, but do perfect Germans exist? Or perfect Jews? They are an abstraction: the transition from the general to the particular always has stimulating surprises in store, when the interlocutor without contours, ghostly, takes shape before you, gradually or at a single blow, and becomes the Mitmensch, the co-man, with all his depth, his tics, anomalies, and incoherences.

Like the element that had spawned their ‘reunion’, Müller was a complex character. Vanadium is a transition metal. When it bonds it forms complexes with different numbers of molecules arranged around the vanadium centre. This gives the vanadium complex different colours. Vanadium can also take many oxidation states; it can be 2+, 3+, 4+ and 5+, which also changes the colour it expresses. Changes in unobservable electrons, have an observable effect.

Sadly, Primo Levi died of an apparent suicide in 1987, throwing himself down a stairwell. He had suffered with bouts of depression throughout his life. In fact the only period that he did not suffer was during his imprisonment.

So what can we learn from The Periodic Table?

  • Be curious about the world around you. Indulge those curiosities constantly. Levi never stopped being curious.

  • Be wary of the ‘almost-the-same’; the hidden differences may lead to radically different consequences. There appears to be very little difference between pride in your own culture, and the denigration of the ‘other’, but there is an important distinction.

  • The material world is much more everlasting than the living. Look after the living.

  • Observe. Observe. Observe. Your observations come together to give you wisdom. Levi would not have survived in Auschwitz without his scientific training, he would not have collected the skills to survive (learning German, building up a knowledge of how the place functioned), and he would not have put himself forward to take the exam which allowed him to work in the lab instead of outside in the winter.

  • Do not be surprised if, when you go from the general to the particular, you are surprised by what you encounter. Today the ‘other’ is often discussed in generic terms, ‘women’ do this, ‘Muslims’ do that, ‘Europe’ thinks something else. The general does not exist.

  • Miniscule changes underneath the surface have significant influence over what is expressed to the world. People, like vanadium, are changed by what is unobservable; their expressions, what they put on show for the world, are the result of all sorts of other things that we cannot see. So we should not judge too harshly.

For the Google Slides click HERE.

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© 2017 by Emily Rose Seeber.