In the last, unfinished book that he had hoped would be his masterpiece, Gustave Flaubert invents two bumbling auto-didacts, Bouvard and Pécuchet, who decide to try their hand at every intellectual speciality the modern world has to offer. They investigate chemistry first in their unsatisfying sampling of the modern sciences, and are dismayed when they realize that they themselves are constituted of the same universal elements as all matter: ‘they felt a kind of humiliation at the thought that their persons contained phosphorus like matches, albumen like egg whites, and hydrogen gas like street lamps’.
They have characteristically got it completely wrong. It is the matches that contain our phosphorus and the street lamps our hydrogen, not the other way round, and we should feel a kind of thrill.
Epilogue
In 1959, Tom Lehrer provisionally concluded his catalogue aria of the elements (then 102 in number): ‘These are the only ones of which the news has come to Ha’vard / And there may be many others, but they haven’t been discarvard.’ Ten more have joined the list since then. It is unlikely that they will gain the cultural traction of their forebears. They are superheavy, radioactive and short-lived, and will never find ordinary applications. They must be made in such tiny quantities that there can be no question of characteristic colours and smells. But, like all the elements before them, they are universal, they are ours; they belong to us as much as the oxygen we breathe. They belong in the periodic table too, at least insofar as they add to the sequence denoted by atomic numbers. And yet, synthesized rather than discovered, made rather than found, they seem to count rather differently.
I wondered what it felt like to bring one of these strange entities into the world. Often, I’ve now come to realize, something revealed at the moment of its discovery will set the course of an element’s career in our culture. Chlorine’s bleaching power was appreciated at the outset; so were the rainbow colours of cadmium. But these new elements, so frangible and fleeting in their existence, could never hope to worm their way into lives like this. In many ways, they must remain unreal, even to those who first make them. Could the exhilaration felt by these discoverers be anything like that felt by William Ramsay and Morris Travers when they stood ‘for some moments spell-bound’ and watched neon first give forth its ‘blaze of crimson light’ or by Davy as he danced round the laboratory in ecstasy at the fiery sputtering of potassium? Did today’s scientists believe their elements were equal to these colourful performers? Unfortunately, they have failed to leave the compelling accounts of their predecessors: in order to get an answer to my question I would have to ask it directly.
I wanted to know, too, how far the periodic table could go. If it were on my bedroom wall now, should I make allowance with rows of empty spaces to accommodate future elements? If so, how many? One or two? A dozen? Hundreds? Not long before he died in 1999, Glenn Seaborg, who first found plutonium and the string of radioactive elements that follow it, gave a lecture in which he showed a table running up to an unnamed element number 168–half as far again as science has managed to push the inventory in 300 years. Was this just fancy, an old man’s hopeless dream? Seaborg seemed to disown the prospect even as he spoke: ‘We’ll do well to just go on up another half-dozen elements or so,’ he said. But then why show the image? Perhaps it was his way of reminding the audience that scientific discovery has a habit of changing the rules as it goes along. When the first ‘true’ chemical elements were identified, there was no way they could be construed as numbers five and six to complement Aristotle’s long-established foursome, earth, air, fire and water. They overturned that system completely and demanded a new one. When he drew up his list of thirty-three elements in 1789, Lavoisier likewise had no means of knowing how many others still lay undiscovered in their ores. In the mid nineteenth century, when the rate of discovery dropped away for a while almost to zero, some chemists may have begun to assume they now knew all the elements there were to know–but then the adventure was set in motion again by the invention of the spectroscope, which allowed many more to be identified by their characteristic flames. Dmitrii Mendeleev, despite making allowance for new arrivals, was still shocked to learn about the existence of the inert gases and the first radioactive elements. They slipped into his periodic table easily enough, even though he fought against their inclusion at first. Will Mendeleev’s design continue to be so accommodating? Or will some new element one day be found that exhibits such outlandish behaviour that the whole table must be broken up and remade?
Who can tell me what it feels like to discover an element today, and how many more such discoveries there are likely to be? For this, I need to track down the surviving discoverers of the newer elements and their successors who are still trying to find yet more, for building the periodic table is a continuing project. Although I trained as a chemist, I am mildly shocked to find I do not know their names. Cosmologists and geneticists familiar from over-exposure in the media, yes. But these chemical pioneers, no. One reason is that they are so thin on the ground. This is not simply due to the attenuated rate of discovery–down from an element every year or two through most of the nineteenth century to one every three years in the twentieth–but also to the fact that elements now tend to be discovered in batches by a few groups of researchers. This leaves fewer winners to claim the glory even if they are so inclined.
Seaborg’s colleague and successor, and the only individual who can rival his record, is Albert Ghiorso. He joined Seaborg’s team at its wartime base in Illinois as part of the Manhattan Project in 1944 and by 1971 could claim to be the co-discoverer of the elements numbered 95 to 105, including lawrencium, rutherfordium and dubnium. When it came to element number 106, Ghiorso was moved to ask his mentor what he thought of the name ‘seaborgium’. Seaborg–who can hardly have thought the day would never come–pronounced himself ‘incredibly touched. This honor would be much greater than any prize or award because it was forever; it would last as long as there are periodic tables. There are just over a hundred known elements in the universe, and only a handful of these are named after people.’ Ghiorso still has a desk at the Lawrence Berkeley National Laboratory at the age of ninety-three. I write to him with my questions. But he does not respond.
After seaborgium, the laurels for the discovery of the following six elements go to the Institute for Heavy Ion Research at Darmstadt in Germany. The senior scientist at the centre during the 1980s and 1990s when these discoveries were being made was Peter Armbruster. This time, I am in luck. When I speak to Armbruster, however, he shrugs off any glory. ‘I didn’t discover them. I always worked with a group.’ But he surprises me by revealing that discovery can still be pinned down to that primal moment when something new irrupts into the senses. In 1981, he and his team of nuclear physicists were trying to make element number 107. The laboratory was still using noisy printers rather than silent computer screens to display results. As the equipment recorded the disintegration of the short-lived atom, ‘we heard a burst of clicks’. Were those clicks any less marvellous than new light in a spectroscope?
The synthesis of these superheavy elements is in principle a matter of simple addition. Uranium is the heaviest naturally occurring element in the periodic table. Seaborg and Ghiorso had made the next elements in the sequence by bombarding targets of uranium–and then plutonium, americium and so on–with much lighter particles in the hope that some of them would stick and so form a still heavier new element. The difficulty with this–and it grew all the time–was that the targets themselves were already unstable. This increased the chance that the bombardment would simply produce a shrapnel of small high-energy fragments and no heavy atoms at all. Armbruster’s breakthrough was to see that if he used atoms of certain middleweight elements as his missiles, he could go back to using stable targets. Element number 107, bohrium, was made by firing chromium atoms at a target of bismuth; 112 by forcing together atoms of lead and zinc. Because the new element survives for a few seconds at most before decaying, it must be detected
not by direct observation, but by measuring the energy of its decay particles and determining the composition of the stable nucleus left behind. From this information, it is possible to calculate the atomic number of the new element that must have existed during the brief moment before the decay. Discovery in these cases is not a matter of eureka moments and apples dropping on heads. The pleasure is more like that felt by the archaeologist who is able to work out from a few shards what an ancient pot must have looked like.
Though the explorers of this far region of the periodic table are physicists, they share the chemists’ urge to describe their new elements and to make compounds from them. They are motivated in this not by some soft-headed nostalgic wish to follow in the footsteps of earlier element discoverers, but by sound scientific principles. Armbruster’s group has succeeded in making compounds such as bohrium sulphate and hassium tetroxide, working with just a few atoms of these elements. This, however, has been enough to prove their chemical analogy with the elements directly above them in the table, thereby demonstrating the continued validity in these uncharted waters of Mendeleev’s organization of the elements. ‘There were speculations that Mendeleev’s table might break down with heavier elements,’ Armbruster explains. ‘The effect of relativity on inner-shell electrons moving at close to the velocity of light would mean that ordinary quantum mechanics would no longer apply. But we found that hassium really behaves like iron and that element 112 is like mercury.’
I ask Armbruster about names. The naming of elements is a chemists’ preoccupation, the nuclear physicist points out. Adding a proton to an atomic nucleus transmutes it into a different chemical element one unit heavier; adding a neutron merely converts it into a heavier isotope of the same element. To the physicist, it seems unfair that it is only the former that warrants a new name. Notwithstanding this, Armbruster has been involved in many naming decisions. Until 1992, he tells me, it was the discoverer’s right to choose a name, but this has changed in response to the priority disputes of the Cold War so that claimants are now only permitted to put forward names as suggestions. I detect a slightly shamefaced tone when Armbruster excuses his team’s naming of elements 108 hassium (after the federal state of Hesse) and 110 darmstadtium. The official justification is that it completed a nesting geographic set along with europium and germanium (Darmstadt, Hesse, Germany, Europe), and was a fitting response to Seaborg and Ghiorso’s earlier naming of americium, californium and berkelium (an event which prompted the New Yorker to quip that if only the researchers could now find universitium and ofium their work would be complete). ‘This bad tradition was established by Berkeley. We wanted to do it for Europe,’ says Armbruster. It seems that nationalism begets nationalism. But there is a more subtle patriotic subtext here too–an historical reassertion of Germanic strength in nuclear physics. For Armbruster’s favourite of the six elements he has helped to name is number 109, meitnerium, named after the partly Jewish Austrian physicist Lise Meitner. Working in Berlin, and then in Stockholm and Copenhagen in exile from the Nazi regime after 1938, Meitner was one of the discoverers of nuclear fission, the process whereby atomic nuclei split to release massive amounts of energy. (Her work also demonstrated why the elements heavier than uranium could not be stable.) Meitner achieved this in the face of Nazi persecution and discrimination against women wherever she went. ‘I was convinced that she was a very important part of nuclear physics in the twentieth century,’ says Armbruster. ‘And she had all the disadvantages you can have.’
By chance, I speak to Armbruster a few days after he has submitted his proposal for the name of element number 112 to the International Union of Pure and Applied Chemistry, the organization in charge of ratifying chemical nomenclature. IUPAC requires each new element to have a name that is easily pronounced and a memorable chemical symbol. The choice for 112 has apparently been narrowed down from thirty suggestions, some Germanic, some Russian, reflecting the make-up of the team that did the research. Their previous discovery, element number 111, was named roentgenium after the German discoverer of X-rays, Wilhelm Röntgen. Armbruster won’t be drawn on what he has recommended this time, but indicates that patriotism is not the inspiration. ‘I did everything to ensure that we do not continue with German scientists and German towns,’ he tells me.*
The scene of the most recent element strikes has shifted to Russia. At the Joint Institute for Nuclear Research in Dubna, Yuri Oganessian leads the team that has synthesized elements numbers 114 and 116 (odd-numbered elements are harder to obtain, for reasons to do with nuclear stability). He offers a more personal insight into the quest. ‘The work is very difficult, since the probability of a new element nucleus formation is exceedingly small. Very often we get nothing. It may take years,’ he says. ‘It is not difficult to understand the emotions of the researcher.’
I ask about the distinction between ‘finding’ and ‘making’ elements. This excites Oganessian: ‘I’d put the question more rudely: why in general do we discover elements?’ What, as he puts it, is the need, having synthesized darmstadtium, say, the nineteenth element following uranium, to synthesize a twentieth? Why go on? His answer goes to the heart of what science is about. The discoveries are important less as trophies and more for what they tell us about the wider world. In Seaborg’s heyday, the theoretical model of the atomic nucleus suggested that the catalogue of elements was essentially finite, and that beyond a certain threshold of instability it would actually be impossible to synthesize newcomers. However, advances in theoretical physics during the 1960s then indicated that there might in fact be ‘islands of stability’ clustered around certain atomic numbers higher up the table. This new understanding has stimulated the hunt for elements that it would have been madness to go after before–and is presumably what encouraged Seaborg to speculate on a periodic table up to atomic number 168. ‘Only at the beginning of the present century have we managed to change the method of synthesis and produce elements with atomic numbers from 112 to 118, and prove that the theoretical hypothesis is a reality,’ says Oganessian triumphantly.
So are recent discoveries any different from those that have gone before? Oganessian denies it. Each one is a prize in itself, but it also says something about how much further the project can go, perhaps appearing to set a new limit on the number of elements that can exist, or alternatively throwing open new doors of possibility. Its greater significance lies in the contribution it makes to the broader mission of science–the increase of human knowledge. ‘Synthesis of a new element is not the end in itself. The efforts of researchers have always been directed to the search for something more important than just filling in the squares of the periodic table. I want to believe that such a motivation doesn’t have any exceptions.’
Oganessian and his colleagues have now set their sights on the difficult element number 117. If it turns out to have the properties of a halogen, it will be further proof of the genius of Oganessian’s compatriot, Mendeleev. If it doesn’t, then it will set chemists wondering anew. ‘It looks as if it is going to be one of the most difficult experiments ever carried out.’
Notes
The pagination of this electronic edition does not match the edition from which it was created. To locate a specific passage, please use the search feature of your e-book reader.
Part One: Power
16 ‘high degree of sensuous’: Veblen, 129.
16 ‘it is the only’: Pliny, 295.
16 ‘long enough to encircle’: Quoted in Chevalier and Gheerbrant, 441.
17 ‘could be completely’: Pliny, 287.
17 ‘The first person’: Pliny, 287.
17 ‘The second crime’: Pliny, 292.
17 ‘symbol of perversion’: Quoted in Chevalier and Gheerbrant, 442.
22 ‘hard, rebellious quartz’: Clemens, 233.
26 ‘in an entirely uncommercial’: Shaw, 8.
26 ‘the cost of extraction’: Herrington, 8.
27 ‘with production in the best’: Herrington, 58.
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28 ‘That gold inwardly taken’: Wilkin, 338.
28 ‘Gold of all the Metals’: Geoffroy, 281.
29 ‘Any fool would know’: Quoted in Wilson, 221.
33 ‘Three months later’: Weeks and Leicester, 397.
38 ‘as shamefully announced’: Quoted in McDonald and Hunt, 156.
54 ‘ochreous stain’: Ruskin, 189.
70 ‘the great burning glass’: Knight, 101.
70 ‘A candle will burn’: Faraday, 106. Faraday appears to have made an error in his estimate of the amount of carbonic acid, as 548 tons is equivalent to roughly 1,200,000 pounds.
72 ‘At some point’: Seaborg, 52.
74 ‘honest-to-God’: Seaborg, 72.
74 ‘Our microchemists isolated’: Seaborg, 99.
74 ‘We briefly considered’: Seaborg, 72.
74 ‘entirely coincidental’: Seaborg, 72.
74 ‘Each element has’: Seaborg, 72.
75 ‘We thought our little’: Seaborg, 72.
75 ‘the UPPU club’: Bernstein, 122.
75 ‘When the husbands’: Seaborg, 94.
76 ‘Plutonium is so unusual’: Quoted in Bernstein, 105.
79 ‘This would be super’: Bernstein, 158.
85 ‘reinforcers’: Quoted in Gillispie.
87 ‘knows everything that happens’: Quoted in Gordin, 245.
88 ‘Symbolic action’: Quoted in Gordin, 245.
90 ‘We thought it fitting’: Seaborg, 155.
92 ‘In mercury the hands’: Cocteau in a conversation recorded with André Fraigneau, trs. Vera Traill (London, n.d. [?1952]).
94 ‘The Chinese have probably’: Needham, vol. 13, 143.
100 ‘As nature produces metals’: Roberts, 34.
Part Two: Fire
118 ‘Take a Quantity’: Quoted in Derham, 187.
Periodic Tales Page 37