Songwriting by numbers

Can a crowd write a song? That’s what an online experiment by computer programmer Brendon Ferris in the Dominican Republic is hoping to determine. Users are invited to vote on the notes of a melody, one note at a time, and the most popular choice secures the next note. The melody is selected to fit an anodyne chord sequence, and as far as I can make out the choices of notes are restricted to those in the major scale of C, the key signature of the composition. I’m not sure if the notes are allowed to stray out of the single octave range beginning on middle C (the New Scientist article provides very few details), but so far they haven’t. In other words, the rules are set up to ensure that this will be a pretty crappy song come what may, with all the melodic invention and vocal range of Morrissey (oh ouch, that’s not going to be popular!).

Even putting that aside, the experiment bears no relation to how music is composed. No one decides on a melody note by note, or at least not outside of the extremes of, say, total serialism, where everything is determined algorithmically. Neither do we hear a melody that way. We group or “chunk” the notes into phrases, and one of the most salient aspects of a melodic line that we attend to – it’s what infants first discern, irrespective of the exact relationships between successive pitches – is the overall contour. Does it go up or down? Is the pitch jump a big or small one? The melodic phrase is, in general, a single meaningful unit, and its musicality disappears once it is atomized into notes. The very basis of our musicality lies in our propensity to arrange sound stimuli into groups: to bind notes together.

But this doesn’t mean that the experiment is worthless (even if it’s worthless as music). It potentially raises some interesting questions (though as I say below, the answers in this case are highly compromised by the constraints). Will this democratic approach to making melody result in a tune that shares the characteristics of other conventional tonal melodies? In other words, can the crowd as a whole intuit the “rules” that seem empirically to guide melodic composition? It seems that to a certain extent they can. For example:

- the crowdsourced melody (to the extent that can be judged so far) exhibits the same kind of arch contour as many common tunes (think of “Ode to Joy” or “The Grand Old Duke of York”, say), rising at the start and then falling at the end of the phrase.

- the contours tend to be fairly smooth: an ascent, once started, persists for several notes in the same direction, before eventually reversing.

- the statistics of pitch jumps between one note and the next exhibit the same general pattern, within the limited statistics so far, as is seen for music pretty universally: that’s to say, there are more small pitch steps than large ones, with most being just zero, one or two semitones (especially two, since this corresponds to the distance between most successive note pairs in the diatonic scale). Here’s the comparison: the statistics for a sample of Western classical music are shown in grey, the thick black line is for this song:


But there are some anomalies, like those weird downward jumps of a seventh, which I suspect are a consequence of a silly restriction on the span of the allowed note to exclude the upper note of the tonic octave: you have to go back down to C because you can’t go up. So perhaps all we really learn in this case is totally unsurprising: people have assimilated enough from nursery rhymes not to be picking notes at random or putting rests in weird places, they have intuited some basic principles of harmony (so that we’re not getting B naturals against an F chord), and that if you permit only the blandest of note choices against the blandest of chord sequences, you’ll get a tune that is of no real interest to anyone.

That’s the opposite of what Ferris was hoping for. “My way of thinking was, if the crowd decides what the next note is, then there must be something there that appeals to the most people,” he has said. “The song should sound good to everybody.” But even if the rules weren’t so badly chosen, this totally misunderstands what music is about. What snags our attention is not the obvious, the consensual, the average, but the unusual, the unexpected. But that can’t be arbitrary: there are also rules of a sort that help to make the unexpected work and prevent it from seeming unmotivated. Whether the crowd could, if given the right options, find its way to that sort of inventiveness remains to be seen; I’d be astonished if it could do so note by note.

Something of this same nature was tried before, with more insight, by the avant-garde jazz musician David Soldier, who is the pseudonym of the neuroscientist David Sulzer at Columbia University. Sulzer wrote a song based on surveys of hundreds of people to discover what elements, such as instrumentation, tempo and lyrics they liked best. He called the result "Most Wanted Song". I haven’t heard it myself, but some people have described it as a sickly abomination, while others have said that it sounds a bit like Celine Dion. Which I suppose is the same thing.

Sulzer’s whole point is that trying to define the perfect song according to some kind of measure of popularity is liable to end badly. I think Ferris is discovering that too.

The cost of faking it

Here, a little belatedly, is my July column for Nature Materials, which considers the issues around bioprinting of fake rhino horn.

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Debates about distinctions between “natural” and “synthetic” materials date back to antiquity, when Plato and Aristotle wondered if human “art” can rival that of nature. Scepticism about alchemists’ claims to make gold in the Middle Ages weren’t so much about whether their gold was “real” but whether it could compare in quality to natural gold. Such questions persisted into the modern age, for example in painters’ initial suspicions of synthetic ultramarine and in current consumer confusion over the integrity of synthesized natural products such as vitamin C.

It is all too easy for materials technologists to overlook the fact that what to them seems like a question of chemical identity is for users often as much a matter of symbolism. Luxury materials become such because of their cost, not their composition, while attitudes to the synthetic/natural distinction are hostage to changing fashions and values. The market for fake fur expanded in the 1970s as a result of a greater awareness of animal conservation and cruelty, but providing a synthetic alternative was not without complications and controversy. Some animal-rights groups argue that even fakes perpetuate an aesthetic that feeds the real-fur market, while recently there has been a rise in real fur being passed off as faux – a striking inversion of values – to capture the market of “ethical” fur fans. The moral – familiar to marketeers and economists if less so to materials scientists – is that market forces are dictated by much more than chemical composition.

These considerations resonate strongly in the current debate over plans by Seattle-based bioengineering company Pembient to use 3D printing for making fake rhinoceros horn from keratin. The company hopes to reduce rhino poaching by providing a synthetic alternative that, by some accounts, is virtually indistinguishable in composition, appearance and smell from the real thing. It claims that 45% of rhino horn traders have said they would buy the substitute. How to interpret that figure, even taken at face value, is unclear: will it help save the rhino, or does it show that over half of the buyers value something more than material identity? In the black-market Chinese and Vietnamese medicines that use the horn, it is supposed to imbue the drugs with an essence of the wild animal’s vitality: it is not just an ingredient in the same sense as egg is a part of cake mix, but imparts potency and status.

The same is true of the tiger bone traded illegally for medicines and wine. Even providing the real thing in a way that purports to curb the threat to wildlife, as for example when tigers are farmed in China to supposedly relieve the pressure on wild populations, can backfire in the marketplace: some experts say that tiger farming has revitalized what was a waning demand.

Critics of Pembient’s plans – the company intends to print tiger bone too – make similar complaints, saying that the objective should be to change the culture that creates a demand for these products rather than pandering to it. There’s surely a risk here of unintended outcomes in manipulating markets, but also a need to remember that materials, when they enter culture, become more than what they’re made of.

Liquid-state particle physics

Here’s my latest column for Nature Materials.

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The ability of condensed-matter physics to offer models for fundamental and particle physics has a distinguished history. Arguably it commenced with the liquid-droplet model of the atomic nucleus formulated in 1936 by Niels Bohr, which provided a simple approximation for thinking about nuclear stability and fission in terms of familiar concepts such as surface tension and heat of vaporization. Since then, real materials systems have offered all manner of laboratory analogues for exploring fundamental physical phenomena that lie outside the range of direct experimentation: for example, the use of liquid crystals to mimic the topological defects of cosmic strings and monopoles [1], the representation of graphene’s electronic structure in terms of massless relativistic Dirac fermions [2], or the way topological insulators made from oxide materials might manifest the same properties as Majorana fermions, putative spin-½ particles that are their own antiparticles [3].

These cases and others supply an elegant demonstration that physics is unified not so much by reduction to a small set of underlying equations describing its most fundamental entities, but by universal principles operating at many scales, of which symmetry breaking, phase transitions and collective phenomena are the most obvious. It’s perhaps curious, then, that particle physics has traditionally focused on individual rather than collective states – as Ollitrault has recently put it, “on rare events and the discovery of new elementary particles, rather than the “bulk” of particles” [4]. One indication that bulk properties are as important for high-energy physics as for materials science, he suggests, is the new discovery by the CMS Collaboration at CERN in Geneva that the plasma of quarks and gluons created by a proton collision with a lead nucleus has emergent features characteristic of a liquid [5].

It was initially expected that the quark-gluon plasma (QGP) – a soup of the fundamental constituents of nucleons – produced in collisions of heavy nuclei would resemble a gas. In this case, as in an ideal gas, the “bulk” properties of the plasma can be derived rather straightforwardly from those of its individual components. But instead the QGP turns out to be more like a liquid, in which many-body effects can’t be neglected.

Shades of Bohr, indeed. But how many many-body terms are relevant? Earlier studies of the tiny blob of QGP formed in lead-proton collisions, containing just 1,000 or so fundamental particles, showed significant two-particle correlations [6]. But in an ordinary liquid, hydrodynamic flow produces coherent structures in which the motions of many molecules are correlated. The new CMS results show that the QGP also has small but measurable six- and eight-body correlations – suggestive of collective flow effects – that are evident in the variations in particle numbers with the azimuthal angle relative to the line of collision. The azimuthal variations indicate that this flow is anisotropic, and the CMS team proposes that the anisotropy comes from a hydrodynamic amplification of random quantum fluctuations of the colliding particles.

So exactly what kind of liquid is this? Since the strong force between quarks and gluons doesn’t diminish with distance, the QGP seems likely to be quite unlike any we know so far. But might it be within the wit of colloid scientists to tune inter-particle forces so as to create a simple laboratory analogue?

References
1. Davis, A.-C. & Brandenberger, R. Formation and Interactions of Topological Defects (Springer, New York, 2012).
2. Novoselov, K. S. et al., Nature 438, 197-200 (2005).
3. Fu, L. & Kane, C. L., Phys. Rev. Lett. 100, 096407 (2008).
4. Ollitrault, J.-Y., http://physics.aps.org/articles/v8/61 (2015) [here].
5. Khachatryan, V. et al. (CMS Collaboration), Phys. Rev. Lett. 115, 012301 (2015) [here].
6. CMS Collaboration, Phys. Lett. B 718, 795-814 (2013).

Added note: Jean-Yves Ollitrault reminds me that perhaps the best example of particle physics borrowing from condensed-matter physics is the Higgs mechanism, which was inspired by the model of conventional superconductivity.

Silence of the geronotologists

I was perhaps a bit cryptic in tweeting about my New Statesman piece on “the immortality business” (which I’m afraid I can’t put up here, but it should be online soon – and NS is always worth its modest cover price anyway). This is what I meant.

When I pester researchers for comments on a topic I’m writing about, I recognize of course that none is under the slightest obligation to respond. That they almost always do (even if it’s to apologize for being unable to help) is a testament to the extraordinary generosity of the research community, and is one of the abiding joys and privileges of writing about science – my impression is that some other disciplines don’t fully share this willingness to explain and discuss their work. Occasionally I do simply get no response at all from a researcher, although it is unusual that a gentle follow-up enquiry will not at least elicit an explanation that the person concerned is too busy or otherwise indisposed to comment.

That’s why my experience in writing this piece was so clearly anomalous. I contacted a large number of gerontologists and others working on ageing, explaining what I was trying to do with this piece. With the very few honourable exceptions named in my article, none responded at all. (One other did at least have the grace to pretend that this was “not really my field”, despite that being self-evidently untrue.) I am almost certain that this is because these folks have decided that any “journalist” contacting them while mentioning names like Aubrey de Grey wants to write another uncritical piece about how he and others like him are going to conquer ageing.

I can understand this fear, especially in the light of what I said in the article: some researchers feel that even allowing the immortalists the oxygen of publicity is counter-productive. But truly, chaps, burying your head in the sand is the worst way to deal with this. A blanket distrust of the press, while to some degree understandable, just takes us back to the bad old days of adversarial science communication, the kind of “us versus them” mentality that, several years ago, I saw John Sulston so dismayingly portray at a gathering of scientists and science writers. What researchers need to do instead is to be selective and discerning: to decide that all writers are going to recycle the same old rubbish is not only silly but damaging to the public communication of science. I would even venture to say that, in figuring out how to deal with the distortions and misrepresentations that science sometimes undoubtedly suffers from, scientists need help. While it is understandable that, say, IVF pioneer Robert Edwards should have bemoaned the way “Frankenstein or Faust or Jekyll… [loom] over every biological debate”, I see little indication that biologists and medics really know how to grapple with that fact rather than just complain about it. You really need to talk to us, guys – we will (some of us) do our very best to help.

Understanding the understanding of science

That the computer scientist Charles Simonyi has endowed a professorial chair at Oxford for the Public Understanding of Science seems a rather splendid thing, acknowledging as it does the cultural importance of science communication (which was for a long time disdained by some academics, as Carl Sagan knew only too well). Richard Dawkins was the natural choice for the first occupant of the position, and indeed it seems to have been created partly with him in mind.

When his incumbency ended and applications were invited for his successor, a few well-meaning folks told me “you should have a go!” I quickly assured them that I am simply not in that league. Little did I know, however, that should I have been overcome with mad delusions of grandeur, I’d not only have stood less than a cat’s chance in hell but would have been specifically excluded from consideration in the first place. The full text of Simonyi’s manifesto in creating the position is reproduced in the second volume of Dawkins’ autobiography, Brief Candle in the Dark. It doesn’t simply say, as it might quite reasonably have done, that the post is for academics and not professional science communicators. No, it goes out of its way to insult the latter. Get this, fellow science hacks:

“The university chair is intended for accomplished scholars who have made original contributions to their field, and who are able to grasp the subject, when necessary, at the highest levels of abstraction. A populariser, on the other hand, focuses mainly on the size of the audience and frequently gets separated from the world of scholarship. Popularisers often write on immediate concerns or even fads. In some cases they seduced less educated audiences by offering a patronizingly oversimplified or exaggerated view of the state of the art or the scientific process itself. This is best seen in hindsight, as we remember the ‘giant brains’ computer books of yesteryear but I suspect many current science books will in time be recognized as having fallen into this category. While the role of populariser may [may, note] still be valuable, nevertheless it is not one supported by this chair.”

OK, I won’t even get started in on this. Richard doesn’t reproduce this without comment, however. He says he wants to “call attention especially” to “the distinction between popularizers of science and scientists (with original scientific contributions to their credit) who also popularize.” It’s not clear why he does this, especially as the distinction is spurious for many reasons.

I might add that Simonyi also stipulates that “preference should be given to specialities which express or achieve their results mainly by symbolic manipulation, such as Particle physics, Molecular biology, Cosmology, Genetics, Computer Science, Linguistics, Brain research, and of course, Mathematics.” So stuff you, chemists and earth scientists. Actually, stuff you too, cell biologists, immunologists and many others.

It doesn’t much matter to the world that I find this citation offensive. I think it does matter that it displays such ignorance of what science communication is about. I would be much more troubled, however, if the chair were not currently occupied by such a profoundly apt, capable and broad-minded individual as Marcus du Sautoy. If it continues to attract incumbents of such quality, I guess we needn’t trouble ourselves too much about the attitudes of its founder and patron.

Dawkins and the Spotted Dick mystery

I have agreed, with some trepidation, to review volume 2 of Richard Dawkins’ autobiography, this one called Brief Candle in the Dark. I guess I figured it might be refreshing to return to the pre-God-bashing, pre-Twitter Dawkins, when he was rightly known primarily as our pre-eminent science communicator (who called out the idiocies of creationism). And on the whole it is: rather than appearing to be the polarizing caricature that Dawkins is often presented as today, he comes across so far in the book as simply a chap with appealing features as well as foibles, not least of which among the former being his touching generosity to students. Sure, there are Pooterish touches (note to editors: if I ever write anything autobiographical that includes the line “I think my speech went down quite well”, then I’m counting on you guys), but also a sense of the humane individual (not to mention the splendid writer) who these days it can be hard to discern behind all the controversy that surrounds him. I should add that I’m still only on page 50.

But there are also occasional glimpses of the Twitter-era Dawkins, springing out Hyde-like from the good Jekyllish doctor. I was particularly struck by a passage in which, apropos of nothing in particular, Dawkins tells us about a “care home for old people in England” at which a “local government inspector” banned the traditional pudding Spotted Dick from the menu on the grounds that its name was “sexist”. This looked to me for all the world like one of those apocryphal “PC gone mad” stories that the Daily Mail loves to run (and then occasionally retract a few weeks later in small print). Could it really be true?

Thee only item that comes up after a quick Google is one reported – well, what did you expect? – by the Daily Mail. There, the change in naming was not occasioned by a prudish, PC government inspector. The story says that staff in a council canteen were totally fed up with a few customers (one in particular) who kept on making lewd and childish remarks whenever Spotted Dick was on the menu, and so they decided to take matters into their own hands – with the extremely ill-advised idea of calling it instead Spotted Richard. A council official then rather shamefacedly decided to intervene and reverse this policy because it looked so silly (and because it was being reported as an example of political correctness). There was no mention of anyone finding the name sexist, nor of officialdom actually trying to be politically correct.

Some Twitter comments challenged Dawkins about this, and his response was that this was not the same story at all. Rather, the Spotted Dickgate that he heard was from “a personal acquaintance, personally vouched for,” and not the infamous Flintshire Spotted Dickgate. And that, it seems, is all we are going to get from him (though you might think he’d be curious about the parallels).

So you must make up your own minds, people. Was Dawkins’ acquaintance recounting what shows every sign of becoming an urban myth, or was this really a case of Spotted Dick strikes again? Can anyone, in any event, figure out how Spotted Dick could be construed as “sexist” – or even, to paraphrase Spinal Tap, as ”sexy”? The anecdote doesn’t really make sense.

Alleged political correctness has of course become one of Dawkins’ bête noirs (bêtes noir?) – after all, it did for his good friend James Watson after Watson betrayed his racist views once too often, and it also came close to doing for his friend Tim Hunt (a much nicer man than Watson) after Tim said something stupidly sexist. Could it possibly be that it suited Dawkins to believe what he was told without feeling the need to inquire further?

If that’s so, it’s simply another example of the kind of confirmation bias that often leads scientists astray, as I discussed here. What is ironic is that this passage comes so soon after Dawkins has given us a rather nice account of the critical thinking that interview questions at Oxford aim to probe. But it’s one thing to be led to false conclusions in research by seeking out the answer you are already predisposed to find; it’s quite another to recycle an anecdote in a way that makes you sound like a ranter in the comments section of the Daily Mail website.

So pending a full disclosure of data and references, preferably in a major peer-reviewed journal, I propose we should avoid propagating the “Spotted Dick” meme, even if the inventor of memes himself repeats it. This has been a public service announcement.

Beckett's epic fail (again)

One of my esteemed colleagues recently finished a nice piece on careers in science by quoting Samuel Beckett: “Ever tried. Ever failed. No matter. Try again. Fail again. Fail better.” The sentiment is entirely laudable: you’ll get things wrong, but don’t be deterred – every time you attempt something and fail, you get a little better. Or something like that.

Yet whenever I see Beckett put to use this way, I can’t help thinking “Hmphrgh”. This is Beckett you’re quoting. Yes, Samuel Beckett. Does anyone believe that he was ever going to write a soundbite of fist-punching, keep-on-goin’ self-motivation?

The line comes, of course, from Beckett’s late work Worstward Ho. I say of course because that’s commonly acknowledged, but I wonder how many have seen or read Worstward Ho. It is, shall we say, opaque even by the standards of a master of opacity. Dense, you might say. Difficult. Now, I love Beckett and find him an intensely funny writer, but funny because of a wry bleakness that makes Will Self seem like a bouncing-bunny optimist. It’s a braver soul than me who will pronounce with certainty on what Beckett was driving at with “Fail better”, but I will bet a pint of Guinness that he did not intend this to be a boiled-down version of that pious little primary-school mantra “If at first you don’t succeed, try, try again.”

It’s wise not to get too po-faced and spluttery about this misappropriation, not least because Beckett would doubtless have appreciated the joke. We get the memes we seem to need, like the martyrdom of Giordano Bruno or the misuse of “deconstruct”, and I’d be a sad fool indeed to think that a blog comment is going to make the slightest difference in squelching them.

But it’s sad that the irony here is so seldom recognized. Indeed, what seems particularly sad is that the opportunity to take a more nuanced view of failure is bypassed by this bit of repurposed wisdom.

Mark O’Connell has a great piece on Slate, called “How Samuel Beckett became Silicon Valley’s life coach.” He says “What has happened here, I suppose, is that a small shard of a fragmentary and difficult work of literature has been salvaged from the darkness of its setting, sanded and smoothed of the jagged remnants of that context”. The result, O’Connell says, is that Beckett is pressed “into service as a kind of highbrow motivational thought-leader.” But in truth “his attitude toward success and failure was more complex and perverse than this interpretation suggests.” That’s surely true.

What, then, was that attitude? Maggi Dawn has a nice interpretation on her blog: “there is a sense in which claiming always to fail is comedy not tragedy. It releases us from the lie of success, frees us from the obligation to adopt its thin veneer, and allows us to do whatever it is we do for its own sake.”

My own suspicion is that Beckett was hinting at the glorious tragedy of our own self-delusion, in which we tell ourselves that we will eventually transform failure into success, and that the world really cares whether we do or not. We are not Steve Jobs but Harold Steptoe (and if you’re too young to get that allusion, you can thank me later for broadening your horizons), doomed forever to be making pathetic plans for betterment in a kind of frenzied desperation, forever glimpsing our cherished goal only to have it snatched from our grasp by the realities of our sad and miserable existence. And perhaps to realise that our only real hope of solace lies in accepting that Albert will always thwart our efforts, so that we might ask well celebrate failure and get drunk with the surly old sod.

But imagine trying to sell that in Silicon Valley.

Does anyone have any questions?

That I can be fairly relied upon to put my foot in it was confirmed after a talk I gave at the Royal Society last week. The Q&A seemed to be going well enough, but then the RS staff said “Well, we’ll have to bring it to an end there.”

“Oh, there’s just one more”, I quickly interjected, pointing out the chap at the end of the row with his hand up. What I didn’t know was that this fellow is a regular at RS events, where he apparently makes a habit of getting bolshy. The attempt to end the proceedings before handing him the mike was not an oversight but a tactful intervention – which I’d now undermined.

As the question began, I thought I could see a way to create a valid question out of what seemed like his skepticism about the way science is used (“delinquent science” was the term). But as he went on (and on), it became clear that this wasn’t a question at all but a rant about how science wastes taxpayers’ money making things that no one wants or needs, regardless of the consequences, and how the person who switched on the LHC didn’t give a damn whether it would make a black hole that would swallow us all, and – OK, you get the point. One of the organizers had to step in to halt the bitter diatribe.

I try to make a point of turning any question into a reason to say something that I hope will be of interest, even if the connection with the question itself is slender. That’s to say, I will try to answer questions as directly as I can, but when they aren’t really questions at all, or when they are questions about fairies or telepathy, I’ll try to move the discussion in what I hope is a useful direction. I have no problem with disagreeing with a questioner (and if, say, I was confronting a climate sceptic then I’d feel obliged to do so). But I would feel uncomfortable making my answer a put-down. Speakers are in a position of relative power in these situations, and so it seems only fair to try to engage with the issues raised rather than to dismiss, far less ridicule, them. The number of times I have been approached after a talk by someone saying “I have a stupid question, so I didn’t want to ask it in public…” makes me realize how many people, probably because of experiences at school, are extremely nervous about putting up their hand, thinking everyone will laugh at them. (I’m not sure that the questions which follow such a disclaimer have ever been stupid in any event – in my experience, people whose questions are genuinely of dubious value, for example when they serve only to showcase the erudition of the questioner, are rarely averse to asking them.)

So what did I do on this occasion? I waffled something about how modest the aims of most science is, and about the common contrast between the way a piece of work is presented to the public and what its real goals are. I don’t know, it was something to say, but it wasn’t terribly insightful. But I came away troubled. Not because I’d been attacked by the questioner, but because I felt I hadn’t dealt with it in the best way. So I asked my wife later – she being far more generous, perceptive and sensitive than I am – if she thought that on this occasion I should have answered more firmly – not by getting into the vague and paranoid issues that the questioner was, after a fashion, raising, but to say explicitly that they were not relevant here. I realized that what he had said was in fact rather rude – not to me (or rather, that aspect doesn’t greatly bother me), but to the audience, who hadn’t come to hear some aimless angry diatribe against science in general. Was it really right to be so tolerant and irenic in this situation? No, she said, it wasn’t. I had every right to deal with such a “question” with firm curtness – to say, perhaps, that I had trouble discerning any kind of question at all in his comments, and that I wasn’t going to launch into a general defence of what science is all about and why it is done. That’s all it would have taken.

I think she is right. Speakers have a responsibility to treat an audience with respect, but the reverse applies too – at least, in a situation like this. I see no reason why questions should not be challenging, even angry, when controversial subjects are being aired (mine certainly wasn't one such), but even then they need to be brief and to the point.

I wonder how others deal with situations like this? The likelihood of getting flaky or strange or irrelevant questions after a public scientific talk (“Do you think drugs allow us to see other dimensions?”) is of course fairly high. One can perhaps try, as I heard Adam Rutherford do recently, anticipate that by asking at the outset “Please try not to be mad”. (It didn’t work though, did it Adam? – the question above is one of those that followed.) But mad questions aren’t so much the issue (though of course one has to try to be sensitive to genuine mental-health issues here, and I’m not being facetious). Rather, what’s the best way of dealing with folks whose determination to mount a hobby horse, or push a particular point of view, or show off, leads them into confrontational or boring rudeness? Should one treat them the way stand-ups treat hecklers, with an acerbic put-down? Or by politely declining to answer the question? (“You know, I don’t think I can say anything very intelligent about that.”) Or with a brusque and magisterial Dawkinsesque dismissal? With attempted humour? (“What have you been drinking?”) When do you hold back, and when do you let rip?

[Postscript: Incidentally, I was awed by how, at a talk last week at the Royal Institution, Frank Wilczek was able instantly to cut to the physics core of left-field questions. Like this:
Questioner: [apropos supersymmetry] Does this have anything to do with wave-particle duality?
Me: [thinks] Um yeah, does it? Or are you just mouthing a buzzword you’ve heard?
Wilczek: Wave-particle duality is what makes this possible, because [I paraphrase] it's the bosonic picture of quantum fields that we’re hoping to unify with the fermionic nature of matter.
Me: [thinks] Well yeah, I knew that.]

Perkin's purple: a journey around London

I have just presented one of BBC Radio 4’s Science Stories, a new series looking at episodes in the history of science. This one tells the tale of William Perkin’s purple coal-tar dye and how it changed the course of chemistry. That, of course, is the kind of grand and often contentious claim these programmes inevitably end up making, but I do feel that there is a case to be made for it here.

The initial plan was for me to take a journey across London, visiting the key locations en route: from Shadwell in the East End to the Royal College of Chemistry in the West End and then the site of the Perkins’ factory in Greenford Green on the outskirts of west London. In the end it didn’t quite happen that way, but I got a few pictures of some of the relevant locations as we recorded, and so wanted to include these here with the original draft of the script – it changed considerably, and I’m sure very much for the better, but this at least tells and illustrates the story. For more details, see Simon Garfield's excellent book Mauve, Tony Travis's authoritative The Rainbow Makers, and my own Bright Earth.

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“A reservoir of dirt, drunkenness and drabs” – that’s what Dickens called Shadwell, and I’m not sure that he wasn’t being affectionate. There’s not a lot of Dickens’ Shadwell left: whatever the bombs didn’t destroy during the war disappeared soon after in the slum clearances. But I can’t say that what took its place has added much to its appeal: all these ugly flats and traffic bollards.

But here’s the place I want. King David Lane. Just down here in the mid-nineteenth century there was a big old house at 1 King David Fort, but now it’s just a council block.


Visiting the site of William Perkin’s family home in Shadwell – on a very blustery spring day!

This was the home of the Perkin family, who were wealthy by the standards of Shadwell. George Perkin was a successful carpenter who could afford to indulge his son William’s passion for chemistry. William had a little home laboratory on the top floor of the house – just a simple place, with a table and bottles of chemicals, no running water, no gas. But when he was 18 years old and still a student, he discovered something here that for once justifies that awful cliché: it changed the world.

There’s a blue plaque here to back me up. “Sir William Henry Perkin, FRS, discovered the first aniline dyestuff, March 1856, while working in his home laboratory on this site, and went on to found science-based industry.”


The blue plaque marking the spot where Perkin discovered mauveine.

Listen to that again: “went on to found science-based industry”. In other words, what Perkin discovered led to the whole idea that industry might be based on science.

That’s an astonishing claim. What could this young lad have found that was so important?

Let’s start with a gin and tonic.

For the British army in India in the nineteenth century, this drink really was medicinal. The troops were issued with their bitter tonic water at daybreak, but the officers started taking this medicine on the verandah as the sun set, not just with a spoonful of sugar but with a splash of lime and a generous shot of gin.

You see, the bitter taste was due to quinine, the only effective anti-malarial drug then known. This stuff was extracted at great labour and expense from the bark of a Peruvian tree called the cinchona. The bark had been known since the seventeenth century to help treat and prevent malaria. No one really knew what was in it until two French chemists separated and purified quinine in 1820. With quinine to protect them, the Europeans were able to begin the colonization of Africa, the consequences of which are still reverberating today.

You really didn’t want to get malaria. Chills, convulsions, fever, vomiting, delirium, and quite possibly at the end of it all – death. But quinine cost a fortune. Peru was then just about the only place where the tree was found and the bark contained only tiny amounts of it. And the Peruvians kept a monopoly by outlawing the export of cinchona seeds or saplings. In the nineteenth century, the East India Company was spending about £100,000 every year to keep the officers and officials in the colonies healthy.

But what if, instead of extracting this stuff drip by drip from tree bark, you could make it from scratch?

What does that mean? Well, over the previous centuries, chemists had found how to take simple chemical ingredients and get them to combine to make entirely different chemicals: useful substances like soap, soda, bleach. Might they be able to make a complicated natural drug like quinine?

One man in particular had this dream of using chemistry to reproduce and even rival nature. He was a German chemist called August Wilhelm Hofmann, and many people, including Prince Albert, hoped that he’d be the savior of British chemistry. In 1845 Hofmann was appointed director of the Royal College of Chemistry in London, which had been set up at Albert’s request.


August Wilhelm Hofmann

So what do we know about Hofmann? Well, according to the sign that now marks the spot in Oxford Street where the Royal College of Chemistry used to stand [it’s next to Moss Bros, opposite John Lewis’s], he “inspired the young to do great things in chemistry, and relate them to both academic and everyday life.”


The plaque erected by the Royal Society of Chemistry to mark the former site of the Royal College of Chemistry in Oxford Street, London.

There were two aspects of everyday life that Perkin, walking down these streets in the mid-nineteenth century, couldn’t fail to have noticed. In the lanes and docks of Shadwell, Dickens said, everyone seemed to be wearing rough blue sailors’ jackets, oilskin hats and big canvas trousers. But up here in the fashionable West End, it wasn’t so different to the style emporiums of today: ladies wore the latest colours: yellow silks from France and fabrics printed in patterns of rich madder red and indigo. Those last two colours were plant extracts, and they faded after lots of washing and being out in the sun. But the yellow silk, which had graced the Great Exhibition in 1851, was coloured with a new dye that was made artificially – by chemistry.

And the stuff it was made of was a by-product of the other thing that distinguished the splendor of Oxford Street from the gloomy alleys of Shadwell: the street lights. They had brightened up the evenings since the start of the century, burning gas that was extracted from coal.

Left over from that process was a thick, smelly tar called, naturally enough, coal tar. At first it seemed to be just noxious waste, and was often just dumped into streams. But then folks figured out that coal tar might be useful. Charles Macintosh used it to make waterproof raincoats. And if you distilled it, then you could extract a whole range of chemicals, like coal itself primarily composed of carbon. They often had an acrid smell – aromatics, the chemists called them. One was carbolic acid, also known as phenol. You remember that stinky old coal-tar soap? That’s phenol you were smelling, and it was in there to act as a disinfectant, one of its main uses since the 1850s.

But phenol was also the starting ingredient for the yellow silk dye that rich ladies bought from Lyon. Yes, this coal tar had some valuable stuff within it.

No one knew that better than August Hofmann, who had become pretty much the world expert on coal-tar compounds. So when William Perkin enrolled at the Royal College of Chemistry in 1853, pretty soon he found himself working on coal tar.

And when Hofmann set Perkin the challenging task of trying to make synthetic quinine in 1856, the coal-tar compounds seemed like good materials to start from.

We need to do some chemistry now. But don’t worry. I’ve got a Scrabble set to help me. You see, molecules are like poems: you have to get the words in the right order. Each word is a cluster of letters, and we can think of each letter as an atom. Making molecules is like stringing together these letters in an order that has some meaning. Now, some molecules, like polythene or DNA, really are a lot like strings of atoms. But others have other shapes. Benzene, for example, which is at the heart of all the coal-tar aromatic compounds, is a ring of six carbon atoms, each with a hydrogen atom attached. I take all six C’s for carbon – and yes, this isn’t exactly a regular Scrabble set – and put them in a ring.

But the problem was that in Perkin’s day no one knew that molecules have shapes like this, with atoms in particular arrangements. All they knew was the relative amounts of each kind of element, like carbon and hydrogen, a substance contained. Benzene was equal parts of carbon and hydrogen, rather like a G&T is one part gin to three parts tonic water.

So then, what Hofmann and Perkin knew about the element cocktail that is quinine was that it is twenty parts carbon, to twenty four of hydrogen, two of nitrogen and two of oxygen.

What gives quinine its meaning – what lets it cure malaria – is its particular arrangement of these atoms. But Perkin knew nothing about that. His strategy – so crude that in retrospect it was obviously hopeless – was, roughly speaking, to take a compound that had half of these amounts – ten parts carbon and so on – and try and stick them together, as if mixing up these two piles of letters is going to miraculously give them the same meaning as quinine.

It’s not surprising he didn’t succeed. When he did the experiment at home one night, instead of colourless quinine he got a red sludge.

He could have been forgiven for just flushing it down the drain. But he was too good a student for that, which is why Hofmann had made Perkin his personal assistant.

Instead, he thinks, well, what seems to be going on here? Let’s try the same reaction with another two identical piles of letters, rather like the ones before but a bit simpler. And so he goes through the same procedure with a different coal-tar extract, one of Hofmann’s own favourites: a compound called aniline.

Well, this time the result is even worse. Now the gunk is black. Even so, Perkin keeps going. He dries the stuff and swills it around in methylated spirits.

And now at last, something nice. It dissolves to turn the liquid a beautiful purple.

Here Perkin thinks of those fine ladies of Oxford Street in their bright silks. He knows that the textile industry is hungry for new dyes. And so takes a piece of white silk and dips it into the liquid, and when he pulls it out the colour has stuck fast to the fabric.

So what now? Perkin manages to get hold of the name of a dye works in Scotland and he sends them a piece of his purple-dyed silk. When the reply comes a few months later, it must make his heart beat faster:
“If your discovery does not make the goods too expensive it is decidedly one of the most valuable that has come out for a very long time. This colour is one which has been very much wanted in all classes of goods and could not be had fast on silk and only at great expense on cotton yarns… the best lilac we have… is done by only one house in the United Kingdom… and they get any price they wish for it, but… it does not stand the tests that yours does and fades by exposure to air.”

So there it was: Perkin had a potential new dye on his hands.

But remember what the man had said: “If your discovery does not make the goods too expensive”. Well, aniline was expensive. If this dye was going to succeed, Perkin had to find a way of making it cheaply – which meant, on an industrial scale.

He realized that he wasn’t going to be able to do that while he was still a chemistry student. So he told Hofmann that he was quitting. But Hofmann had made the young man his protégé, and as Perkin recalled many years later, “he appeared much annoyed”. What was his best student thinking of, abandoning a promising career in pure research to go into industry? As Perkin recalled,
“Hofmann perhaps anticipated that the undertaking would be a failure, and was very sorry to think that I should be so foolish as to leave my scientific work for such an object, especially as I was then but a lad of eighteen years of age.”

The funny thing is that purple was already fashionable even before Perkin discovered his aniline dye. From the 1830s a purple dye called murexide became popular, though probably its fans had little idea that it was made from Peruvian bird droppings. Another purple dye was made from an extract of lichen. In the year that Perkin made his discovery, the Pre-Raphaelite Arthur Hughes painted his picture April Love, showing a young woman in the kind of long flowing purple dress then in style. The French, who even at that time called the shots in fashion, had a word for these rather pale purples. It was what they called the purple-flowered mallow: mauve.


April Love (1856), by Arthur Hughes.

But he did leave, and when he couldn’t find a backer for the factory he proposed to build, his father George put up his life savings, even though he’d never wanted William to become a chemist in the first place. William’s older brother Thomas chipped in to help too.

Now they had to give aniline purple a catchy trade name. Perkin thought of the famous royal purple of Rome, originally made in the Phoenician city of Tyre from a substance extracted a drop at a time from shellfish. Why not call it Tyrian purple?

But it didn’t catch on. Soon enough the aniline dye he’d intended to call Tyrian purple had become synonymous instead with the colour mauve.

There was nowhere suitable in the East End for the coal-tar dyeworks of Perkin & Sons, and in the end they found a meadow right over in Greenford Green, near Harrow, northwest of London, conveniently close to the Grand Junction Canal. In less than six months, a factory was turning it into purple for the dyers of Great Britain.

Well, I can’t say that the industrial estate in Greenford Green is much of an improvement on the faceless modern development in Shadwell. But I guess it wasn’t any better in Perkin’s day. His dyeworks grew quickly, and it looks pretty grim in old engravings and photos, with its tall chimneys belching smoke and toxic nitrous fumes. He found a way to make aniline cheaply on the site from benzene, sulphuric and nitric acid, so goodness knows what the factory’s chemical vats spewed into the canal. The chemical process was dangerously explosive, and none of the Perkins had any experience with industrial-scale chemistry. It’s a wonder the whole place didn’t go up in smoke.


A photograph of the Perkins’ dyeworks in Greenford Green.

The last traces of the old factory were destroyed in 1976, but there’s a blue plaque here to mark its place… and here it is. “William Henry Perkin established on this site in 1857 the first synthetic dye factory in the world.”


The blue plaque at Greenford Green where the original coal-tar dye factory of Perkin and Sons once stood.

It became so much the rage in London that it even drew comment from Dickens in 1859:
“As I look out of my window, the apotheosis of Perkin’s purple seems at hand – purple hands wave from open carriages – purple hands shake each other at street doors – purple hands threaten each other from opposite sides of the street; purple-striped gowns cram barouches, jam up cabs, throng steamers, fill railway stations; all flying countryward, like so many migrating birds of purple Paradise.”

Perkin’s Greenford Green factory marks the end of the beginning – for aniline dyes and for the entire synthetic chemicals industry.

Perkin & Sons couldn’t get the French patent rights for their mauve, and within a year French and German companies started to make it too. Soon the coal-tar dyes were everywhere – not just purple but green, red, blue, black. The liberation of colour had arrived, and fashion became positively gaudy.

Bright colour – once the preserve of the rich – could be worn in all walks of life. Gone was the colour-coding of social hierarchies that had existed since the Middle Ages. Colour became a matter of individual expression.

What began as a stroke of serendipity in Shadwell was now becoming an exact science. Chemists came to understand that the particular arrangement of atoms in a molecule determines what it does – what, as I said earlier, the molecule means. And what it does might include which colours it absorbs and which it reflects, when light shines onto it.

So on the one hand, it became possible to make new colours to order. By carefully studying aniline dyes, chemists in the late nineteenth century could predict from the architecture of these compounds what colour they were likely to have. This is now the entire business of synthetic chemistry: constructing molecules with particular atomic arrangements and therefore particular properties.

On the other hand, if there was a substance found in nature that had useful properties – like quinine, say – then if you could figure out the shape of its atomic framework you had a chance of working out how to make it synthetically, perhaps more cheaply than harvesting it from plants.

But what became of the natural dyes, such as indigo and madder? They didn’t go out of fashion; instead, synthetic chemistry re-invented them. Getting these substances pure and in large amounts was costly and labour-intensive, and indigo plantations in India were the British Empire’s most lucrative business in all of Asia.

But as chemists came to understand that molecules were made of atoms linked together into particular architectures, they turned themselves into molecular architects who could even aspire to construct the molecules of nature. They figured out how, from simple ingredients like coal-tar substances, they could string together atoms to make the very molecules that gave indigo and madder their colours.



The molecular structures of indigo (top) and alizarin (bottom), which gives madder red its colour.

When two German chemists figured out how to make synthetic madder red in 1868 from the coal-tar compound anthracene, William Perkin quickly figured out how to do it more cheaply and on an industrial scale. By 1873 he’d got rich enough from this and other dyes to sell his company and return to pure research.


The blue plaque in Victory Place, near Elephant and Castle in southeast London, showing where the dyeworks of Simpson, Maule and Nicholson was situated. The company was established here in 1853, and in 1860 it began to manufacture aniline red dye, known also as magenta. Three years later they marketed an aniline violet, discovered by August Hofmann, that offered Perkin’s mauve some stiff competition. In 1873 William Perkin sold his dye company to the firm that Simpson, Maule and Nicholson had become, called Brooke, Simpson and Spiller. I was terribly excited when I discovered this plaque on my usual cycling route into London; I suspect I was the only person who could say that for a good many years.


Portrait of William Henry Perkin, painted in 1906 by Arthur S. Cope.

Perkin’s main competitor for synthetic madder was the German chemicals company BASF. If you’re like me, the name BASF will put you in mind of cassette tapes. But that’s just an example of how the dye companies diversified into other areas, because BASF stands for Badische Anilin und Soda Fabrik: the aniline and soda makers of Baden.

In 1877 one of their academic consultants, the German chemist Adolf Baeyer, worked out how to make indigo from the coal-tar extract toluene. BASF was soon producing it by the hundreds of tons. Within just a few years the price of indigo plummeted and the colonial plantations were put out of business, which the British government declared a national calamity.

Doesn’t this then make the chemist a kind of modern Prometheus? If you can control the shapes of molecules, what can you not create?

These colour manufacturers now pervade our language, our material world, our history. ICI, Hoescht, Agfa, Novartis – all began with dyes. In 1925 some of the major German dye companies merged to form the notorious cartel IG Farben, a force powerful enough to dictate its terms to Hitler. The diversification into pesticides left IG Farben with the patent for the poison gas Zyklon B, which it licensed for use in the concentration camps.

The diversification of the great dye companies into areas like pharmaceuticals had begun by the late nineteenth century. The coal-tar dyes themselves showed the way. In the 1870s the German physician Paul Ehrlich began to use the dyes for staining cells, which made them easier to see and distinguish under the microscope. He found that some dyes actually killed the microorganisms they stuck too.

That sounded useful. In 1909 Ehrlich discovered an arsenic-containing dye that would destroy the microorganism responsible for one of the most feared and deadly afflictions of the day: the disease that dare not speak its name, syphilis. Other coal-tar dyes worked as antibiotics.

Before this time, most drugs were, like quinine, extracts from natural sources, mostly from plants – like the extract of willow bark called salicylic acid that had long used as a painkiller. In 1897 a chemist at the German dye company Bayer turned phenol into a compound related to salicylic acid but which worked even better. The company started selling it under a trade name: aspirin.

To make sense of the science behind all this, chemicals companies couldn’t just any longer rely on hiring the services of academics. They started to employ their own chemists, who could design products like drugs based on a rational understanding of how the molecules needed to be shaped, and what they would do.

This, then, is what science-based industry is all about. It’s what the pharmaceuticals industry looks like today.

All the same, the revolution that Perkin began is in some ways still just getting started. We now know that there’s more to the way a drug works than just a good fit with the biological molecule that it aims to latch onto, like a lock and key. But we still can’t always fully understand or predict how a given drug will behave: you can’t be sure of designing it at the drawing board. Instead, most drug discovery still relies on trial and error, on shuffling molecular fragments into many different shapes and then seeing which ones work best.

What’s more, synthetic chemistry still has plenty of problems to solve: scientists struggle to put together some of the complicated molecules that nature produces. And even if they succeed, the route is often too long and too expensive to be useful in industry. This is why chemical synthesis is still as much an art as a science.

But Perkin is now regarded as one of its finest early stylists: a man who first gave us a glimpse of what might be possible if we can get clever enough at molecular architecture. And for that we have to thank the colour purple.

Against big ideas

Sam Leith’s comment on the trend in non-fiction publishing is spot-on, and Toby Mundy’s analysis of it typically insightful. (And I’m not saying that just because you’re the new director of the Samuel Johnson prize, Toby – though, you know, congratulations and all.) Sam echoes my impression, though I suppose as someone published in the UK by Bodley Head (rightly exonerated here as a noble exception) and in the US by the University of Chicago Press, I would say this. It is good to have critical reviewers around, like Steven Poole and Bryan Appleyard, who will challenge this Gladwellization of non-fiction, but I fear they’re fighting against the tide. Sam’s complaint about the way the mainstream trade publishers seem mostly interested in books that offer a single “big idea” that explains everything about being human/history/the brain/the economy/the internet/the universe (until the next one comes along) is very well founded. Life is not just complex (in which case “complexity theory” would explain it all right?) but complicated. So are most areas of science. So are people. We need ideas and narratives that help us unravel the threads, not ones that pretend it is all just one big rope. This seems especially problematic in the US, where it feels ever harder – outside of the university presses – to publish a serious discussion of any topic rather than an airport book in which the subtitle tells you all you need to know. It’s very reassuring to hear that being published there by a university press there is increasingly a guarantor of substance.

The many truths of Tim Hunt

Blimey. That Tim Hunt then. It feels like any single point of view is not enough; I need a superposition of states here. I read Athene Donald explaining that, however much we can and should deplore his comments, he’s not a bad chap, and I think yes, that was very much my experience of Tim when I was on a judging panel with him: I liked him, found him not at all bigoted or oppressive or objectionable. Comparisons with Jim Watson are unfair – I think it is clear he is not that kind of person. Athene seems right to be saying, let’s not make it all about Tim, we need to focus on measures that will rid science of the blight of sexism that still evidently afflicts it.

Then I read responses and comments by Jenny Rohn, Margaret Harris and Deborah Blum, and I think yes, we mustn’t offer up feeble “he’s just a different generation” excuses and give a basically decent chap a break for making a stupid blunder. There is too much of this sort of low-level crap going on in science all the time, and when it comes from someone in a position of such authority and influence then we need to come down hard on it.

I can’t help feeling a bit sorry for Tim, seeing how genuinely distraught and despairing he seems. Christ, the man is human, and not a monster. And yet I can’t help feeling, you bloody fool, what really did you expect? And I don’t know quite what to believe anyway. Do we accept this as a bone-headed attempt at a joke, or do we believe that Tim passed up the chance to say later that of course he didn’t truly think these things? Do we believe rumours that Tim had form for this kind of thing, or accept the testimony of friends and colleagues that they’ve never seen him previously behave in a sexist manner?

The world can’t possibly need someone else saying “Here’s what we should do about Huntgate.” (I’m glad that’s not a word. Forget I wrote it.) But. Well, I’d simply like to offer a fee suggestions:
1. We stop name-calling and belitting of anyone who, while condemning the remarks, differs slightly from our own view of what is the appropriate way to deal with them. There’s no obvious right answer to that. What’s needed is discussion. (Obviously, this excludes London mayors who think Tim was merely pointing out some well known gender differences, and who in any event reckon it is OK to make off-the-cuff jokes about “piccaninnies”.)

2. We agree that denouncements of “politically correct witch hunts” are beside the point. People on Twitter will say horrid and unfair things about Tim Hunt because people on Twitter do that. Why cares (aside from the fact that it’s intrinsically nasty)? I see no reason to call the responses of, say, UCL, a witch hunt, let alone a “politically correct” one (unless your view is that it is trendy political correctness to show disapproval of sexism and want to distance yourself from it).

3. Tim’s situation has been worsened by the timing. People are frankly and rightly sick of the sexism that exists in science. When I think that my girls, were they to choose careers in science, might have their prospects damaged by bias, harassment, and exclusion, I want to take a hammer and smash up a lot of Pyrex. Actually I think I will encourage them to do it themselves (I suspect they’ll be quite good at it). I’m not saying that Tim got worse than he deserved for this reason, but just that it’s a part of the explanation for what happened.

4. We follow Athene’s action points, and use this sad affair positively to make change happen.

5. We stop making excuses. We can all make mistakes and say thoughtless things, for sure, but having an attitude that fundamentally opposes discrimination of all sorts and recognizes it when we see it in so obvious a manner as this is not bloody hard, whether you are 17 or 70. Science is, frankly, a bit crap at this. It tolerates obnoxious fools for too long, on the grounds that they once did some good science. (I’m not talking about Tim here.) It doesn’t just tolerate them, it excuses them. I don’t give a toss how good your science is, if you don’t behave decently and respectfully then you should expect to get no respect in return.

But here’s what gives me great hope and comfort: I’m not sure science is going to be this way much longer. It’s going to take time and effort, but it will change. I am buoyed by the fact that the ambassadors for science these days (and here I’m qualified only to talk about the UK) are people for who “jokes” about women scientists (no, “girls”) falling in love and crying and working in segregated labs aren’t just objectionable but utterly bloody weird. People to whom it would never occur to say or think such an outlandish thing no matter how “confused” or “nervous” or jet-lagged or drunk they were. People like Athene Donald, like Monica Grady, Alice Roberts, Maggie Aderin-Pocock, Brian Cox, Jim Al-Khalili, Mark Miodownik, Ed Yong, Andrea Sella. Certain older members of the science-communication fraternity (I use the word advisedly, and mention no names) might just purse their lips and mutter about witch hunts and the waste of scientific eminence. But their time is over.

Christiaan Huygens - the first astrobiologist?

Necessarily cut from my piece in Nautilus on water and astrobiology was a paragraph of very early history, in which Christiaan Huygens anticipates this whole debate with eerie prescience. I hope it’s worth filling in that bit of the story here.

Galileo had looked at the moon and saw not the smooth, featureless sphere that Aristotelians believed in but mountains and valleys, their rugged topography picked out by the raking light of the Sun at the boundary where light meets darkness. Within just a couple of decades, writers and philosophers were starting to imagine journeying to this new world, much as Columbus had travelled to the Americas. The natural philosopher John Wilkins gave a factual account in his Discovery of a World in the Moone (1638), while the French soldier and writer Cyrano de Bergerac penned a satirical account of spaceflight in The States and Empires of the Moon, published posthumously in 1657. By the end of the century, scientists were starting to speculate about what the environments of these other worlds might be like.

In his posthumously published 1698 book Cosmotheoros, Huygens asserted that plants and animals on other planets must derive their “growth and nourishment” from “some liquid principle”. But he realized that water would freeze on Jupiter or Saturn, and so “Every planet therefore must have its waters of such a temper, as to be proportion’d to its heat”: Jupiter’s and Saturn’s “waters” must have a lower freezing point, and those of Venus and Mercury a higher boiling point. In other words, it isn’t too fanciful to say that Huygens was speculating that life on other planets might use non-aqueous solvents.

In my Nautilus article I veer towards the notion that there might be non-aqueous solvents for life. In my more technical article for the book Astrochemistry and Astrobiology (eds I. W. M. Smith, C. S. Cockell & S. Leach; Springer, Heidelberg, 2013), I equivocate rather more. It seems to me that this kind of Socratic dialogue (to be absurdly grandiose about it) is the best way of approaching the problem: one can make both cases, and it is hard to adduce any clear evidence at this point for which of them we should prefer. This is what I say in that latter piece:

“Attempts to enunciate the irreducible molecular-scale requirements for (as opposed to the emergent characteristics of) something we might recognize as life have been rather sporadic, and are often hampered by the difficulty of looking at the question through anything other than aqua-tinted spectacles. From the point of view of thinking about non-aqueous astrobiological solvents, a review of water’s roles in terrestrial biochemistry surely raises one key consideration straight away: it is not sufficient, in this context, to imagine a clear separation between the ‘molecular machinery’ and the solvent. There is a two-way exchange of behaviours between them, and this literally erases any dividing line between the biological components and their environment.

The key questions here are, then, necessarily vague. But the more we understand about the biochemical aspects of water, the less likely it seems that another solvent could mimic its versatility, sensitivity and responsiveness, for example to distinguish any old collapsed polypeptide chain from a fully functioning protein. It is perhaps this notion of responsiveness that emerges as the chief characteristic from a survey of water’s biological roles. It can be manipulated in three dimensions to augment the influence of biomolecules. It can receive and transmit their dynamical behaviours, and at the same time it can impose its own influence on solute dynamics so that some biomolecular behaviours become a kind of intimate conspiracy between solute and solvent. This adaptive sensitivity seems to facilitate the kind of compromise between structural integrity and reconfigurability that lies at the heart of many biomolecular processes, including molecular recognition, catalytic activity, conformational flexibility, long-range informational transfer and the ability to adapt to new environments. It is easy to imagine – but very hard to prove! – that such properties are likely to be needed in any molecular system with sufficient complexity to grow, replicate, metabolize and evolve – in other words, to qualify as living.

In these respects it does seem challenging to postulate any solvent that can hold a candle to water – not so much in terms of what it does, but in terms of the opportunities it offers for molecular evolution. This is by no means to endorse the dictum of NASA that astrobiologists need to ‘follow the water’. But hopefully it might sharpen the question of where else we might look.”

Set for chemistry: a longer view

It seems quite a lot of folk liked to hear about the old chemistry sets that I discussed in my article in Chemistry World. It was certainly a blast writing it. I didn’t mention, because she asked me not to quote yet, that Rebecca Onion has also been looking into this topic – I hope it’s OK to say now that she'll shortly be publishing something rather wonderful on it. In any event, I thought it would be worth putting up the full original article here. The images are, except where indicated, all courtesy of the Chemical Heritage Foundation, and I reckon that their exhibition in the autumn is going to be fabulous.

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As you’re reading Chemistry World, I bet you had a chemistry set. Maybe you tinkered with a substantial rack of test-tubes containing compounds that would now be considered daring: potassium permanganate, sodium thiocyanate, perhaps supplemented with stronger stuff bought at the chemical supplier’s or “borrowed” from school: nitric acid, lumps of sodium under oil. Younger readers might have been denied such pleasures, having to be content with litmus paper for measuring soil pH. Today’s sets are likely to be more about “kitchen chemistry” or “colour chemistry”, using nothing more hazardous than bicarb and food dyes.

The content, appearance and aspirations of your chemistry set age you as much as your choice in music. When I recently got to look at the marvelous collection in the vaults of the Chemical Heritage Foundation in Philadelphia, I was struck by how these alluring boxes encode social narratives. They reflect changing perceptions of chemistry and science as a whole, shifts in the social strata of the target consumers, in attitudes to gender and in the objectives of science education. “Chemistry sets and science kits contained much more than vials of chemicals, test tubes, and microscopes”, says art historian and independent curator Jane E. Boyd, who is curating an exhibition of the CHF’s sets that opens in October. “Their colourful boxes and cases also held manufacturers’ ambitions for success and prestige, parents’ hopes and anxieties for the future lives of their sons and daughters, and children’s own desires for fun and excitement.”

What were these sets for? Are they toys? Were the meant to educate or to amuse? Why were they produced, and for who? And why do they seem – I’m sure it isn’t just me – to pack such a nostalgic punch?

The magic of chemistry

Chemical sets aimed at children started to appear from around the 1830s. One of the earliest was the “No. 1. Youth’s Laboratory, or Chemical Amusement Box”, produced in 1836-7 by the chemist Robert Best Ede. It contained “more than 40 Chemical preparations and appropriate apparatus, for enabling the enquiring youth… to perform above 100 Amusing and Interesting Experiments with perfect ease and free from danger.” These cabinets were luxury items: Ede’s was mahogany-cased and sold for the tidy sum of 16 shillings. Historian Melanie Keene of Cambridge University has shown, while the contents of the nineteenth-century cabinets were quite ambitious in their chemical scope, containing such compounds as potassium “superoxalate”, “prussiate” and “bi-chromate”, the emphasis of the booklets was on making chemistry “familiar”, with reference to household items such as soap or candles [1].


Robert Best Ede’s “Portable Laboratory”, c.1836. Wellcome Library, London.

It wasn’t until the second half of the nineteenth century that toy manufacturers began to make commercial sets as educational tools tailored for the affluent middle classes. The intended audience is clear from one of the CHF’s earliest items, a Chemcraft set sold around 1917 by the Porter Chemical Company in Hagerstown, Maryland, one of the major manufacturers of chemistry sets in the USA throughout most of the twentieth century. Like Ede’s set almost a century earlier, it is housed in a handsome wooden box with the ingredients kept in elegant little wooden bottles. The lid shows a well-bred young lad in suit and tie, hair neatly gelled, bending over his little burner under the watchful eye of his father.



Alongside but independent of the chemical cabinets, science popularizers of the nineteenth century produced how-to manuals describing experiments for children using household ingredients. Ede’s earliest cabinets were intended to accompany the popular 1823 book on chemical experimentation, Chemical Recreations by John Joseph Griffin – but Ede’s company later sold them independently with its own bespoke pamphlet. These two traditions of the cabinet and the booklet merged, so that when the cabinets became available to a wider “toy” market at a slightly cheaper price from the 1900s, the accompanying instruction manual became indispensible.

Both the early chemistry sets and the experimental booklets had a strong link to the tradition of “performative chemistry” that developed during the nineteenth century. Dramatic chemical demonstrations were a hallmark of the public talks at the Royal Institution given by Humphry Davy and Michael Faraday in the early part of the century. “These performances were intended to make chemistry ‘familiar’, as enticements to active practical investigations that could be carried out in the home”, says historian of science Salim Al-Gailani of the University of Cambridge, who has made one of the few detailed studies of chemistry sets [2]. He says there is a clear link between publications such as Faraday's book of his RI lectures, Chemical History of a Candle (1861), the penny-pamphlet handbooks, and later chemistry-set manuals.

Chemistry displays, lodged somewhere between music-hall spectacle and public education, were refined at institutions such as the Royal Polytechnic Institute in London, where lecturers like John Henry Pepper wowed audiences with chemical magic. Pepper, best known for devising the illusion of “Pepper’s ghost” used in performances of Hamlet and A Christmas Carol, went on to set up his own Theatre of Popular Science and Entertainment at the Egyptian Hall in London, the home of Victorian stage magic, and took his show on tour in the USA and Australia. Some stage magicians were even contracted to write popular treatises on chemistry.


A chemical manual from c.1894, in which the link to stage magic is clear. (Harry Price Library, UCL)

This link between stage magic and the early chemistry sets is personified in Albert Gilbert, the founder of the A. C. Gilbert Company of New Haven, Connecticut, which was the main US rival to Porter’s Chemcraft and became one of the biggest toy firms in the world. Gilbert was a stage magician, and he founded his company in 1909 to supply materials for magic shows, marketed under the brand Mysto Magic.

The early Chemcraft sets reflect this association too, promising “Mysterious experiments in chemical magic.” There were hints of a connection with alchemy, for example in the suggestion that the deposition of copper onto iron was a kind of transmutation. The manuals offered tips on how to stage a magical demonstration, combining practical instruction with the misdirection and sleight-of-hand methods of the magician. This dabbling with the old imagery of alchemy was sometimes filtered through racial stereotyping that seems shocking now. One Chemcraft manual suggested that the performer dress as some sort of Oriental fellow, like a “Hindu prince or Rajah.” And he would need an assistant “made up as an Ethiopian slave”, with “his face and arms blackened with burned cork”. He should be given “a fantastic name such as Allah, Kola, Rota or any foreign-sounding word.”

“The influence of ‘natural magic’ continued to shape the iconography and pedagogical function of chemistry sets well into the twentieth century”, says Al-Gailani. Even one of the CHF’s most recent sets, from around 1994, was marketed under the “Mr Wizard” brand, harking back to the American television show Watch Mr Wizard produced and presented by Don Herbert from 1951 to 1965. Herbert aimed to demonstrate the science behind the everyday, and he revived the show (and the brand) from 1983 to 1990 as Mr Wizard’s World for the children’s channel Nickelodeon.


Still revealing the magical secrets of nature in the 1990s?

While children might delight in the prospect of mysterious thrills, the parents who forked out for these sets were more likely to be persuaded by the idea that they would be educational and improving. Chemistry experimentation was often presented in the late nineteenth century as morally virtuous: as Griffin put it, “Chemistry is a subject qualified to train both the mind and the hands of young people to habits of industry, regularity, and order”. Such manuals stressed cleanliness, dexterity and common sense – a stark contrast to the “diabolical sorcery” that one might find promised in magic-themed chemistry. The early twentieth-century makers of chemistry sets sometimes tried to reconcile the contradictions by suggesting that they were demystifying the stunts still then being pulled off by mediums and spiritualists. As one Gilbert manual put it in 1920, “We explain how they are performed by purely natural means.”

This tension, says Boyd, is just one of the “many contradictions inside these eye-catching boxes: between dreams and reality, structured learning and free exploration, mysterious magic and rational science, safety and danger.” The boxes in which the kits were housed sent out contrasting messages about what home chemistry was all about. Many show the experimenter as a young scientist, in the time-honoured chemist’s pose of holding up a test-tube or flask of coloured liquid. Some offer a futuristic, utopian vision of science as saviour, perhaps with the tubes of a chemicals plant hovering in the background. “Experimenter today, scientist tomorrow”, promises a Chemcraft manual from 1934.


A brave new world promised by Chemcraft.


“Experimenter today, scientist tomorrow”

Toys for the boys

The imagery throughout is decidedly male. “Manufacturers’ expectations and assumptions about masculinity are particularly apparent in chemistry set marketing copy in the United States in the twentieth century”, says Al-Gailani. He points out that, after the Second World War, chemical experiments that might earlier have been presented as “magic”, such as invisible ink, would instead be likened to the crime-sleuthing associated with the FBI, “an institution that was immensely influential in defining and popularising the predominant ‘all-American, square-jawed’ masculinity of the post-war era”. Chemistry was not just a male but a manly affair. The disheveled “mad scientist”, while beginning to feature in movies, is nowhere to be found here – instead, the young experimenter is smartly dressed and well disciplined, accustomed to following instruction (manuals). If he obeyed the rules, a chemistry set wasn’t just a recreational pursuit but a preparation for a career in science.

Did girls get a look in? A British Lott’s set from around 1915 claims that it is for both boys and girls, and reassuringly places the home chemistry lab in what looks rather like a domestic kitchen, albeit with (highly questionable) periodic tables on the walls. But if girls did chemistry, it was with a view to preparing them for their obligations in “mother’s kitchen”, not the laboratory. As a Chemcraft manual put it in 1933 “in the home, the housewife who knows nothing of the chemistry of the foods she prepares or the materials which she uses daily is handicapped”. The man who knows no chemistry is handicapped too, the manual adds – but strictly in the professional, not domestic, domain. It was the father’s duty to inculcate such knowledge in his son in preparation for a life of work, just as the mother should educate her daughter in the chemistry of cooking and domestic chores.


A Lott’s chemistry set made in England, c.1915


For boy’s only?

When Gilbert finally produced a set specifically for girls in the late 1950s, fetchingly decorated in pastel pink, it is not exactly a “chemist’s set” at all. Instead it reminds the girl who squints into a microscope, while her big sister looks on encouragingly, that all she can aspire to is to use her natural domestic skills to become a “lab technician”.


…or for girls too (if they don’t aspire too high)?

Keeping safe

By the 1970s things seem to have improved a little. Both girls and boys, as golden-haired and wide-collared as David Soul, feature on the lid of Johnny Horizon’s chemical set, although the girl seems to be reduced to looking on adoringly as her brother (boyfriend?) does the measuring and pouring. Yet this is no longer marketed as a chemistry set: in the post-Silent Spring era it is now an “Environmental Testing Kit”. “Is the air around you polluted?” it asks. You can examine river waters for contamination too, and the set promises that you and your family “will be able to do more about our environmental problems.”


A chemistry set post-Silent Spring.

How times change. What would those who bought the Johnny Horizon kit have made of Chemcraft’s offering from the late 1940s, which includes “safe experiments in atomic energy”, including – probably my favourite element (literally) of the entire CHF collection – uranium ore and a “radio active screen”? The latter is incorporated into a “spinthariscope”, a device first invented by the chemist and entrepreneur William Crookes in 1903, which uses a zinc sulfide phosphor screen to reveal the scintillations of alpha particles.


Home experiments in atomic energy, c. 1948.

Compare this with the Tree of Knowledge Chem-Science set from around 2000-2005, which – despite offering standard experiments such as the bicarb-vinegar volcano and litmus testing – assures the buyer that the “35 fun activities” contain “no chemicals”.


The Tree of Knowledge Chem-Science set (c.2000-2005) takes no risks.

If you’re inclined to bewail this apparent taming of home chemistry for kids, bear in mind that social anxieties about safety are nothing new. A concerned parent wrote to the Times in 1903 warning that “the placing in the hands of young boys of such ingredients as chlorate of potash, sulphur, &c., must always be deprecated as a temptingly dangerous proceeding”. (If only we could have responded by saying “Yes, that’s the point.”)

“The idea that the sets used to have terribly dangerous materials in them, and then these gradually got nanny-stated out, isn’t fully supported by the sets themselves”, cautions CHF curatorial assistant Elisabeth Berry Drago. “Even the earliest sets contained fairly innocuous stuff: things that were corrosive, or shouldn’t be inhaled, but not intrinsically deadly or dangerous.”

Compare, for example, the contents of the Lott’s chemistry set from around 1915 with those of a 1965 Skil Craft set (see Box): there was rather little change over five decades. “The ads and print material demonstrate that a concern for safety and toxicity was not a late development, but something that was very much a part of the context from early on”, says Drago. “Even in 1917 the onus is on safety.” The Porter Chemcraft set from that era insists that it is “Perfectly safe” and “Contains no poisonous or otherwise harmful substances”. Yet there was probably more concern about the sources of heating than about the chemical ingredients. Early chemistry sets contained Bunsen burners, Drago says, while later even “alcohol lamps with open flames are not considered child-safe any more.”

This wasn’t simply a matter of changing perceptions of what was hazardous, but also of who was to blame: as medical historian John Burnham of Ohio State university has argued3, there was an increasing tendency over the course of the twentieth century to switch the responsibility for child safety from parents (particularly mothers) to manufacturers and the “engineering” of the childhood environment. If manufacturers were to be held responsible for accidents, they weren’t going to take any risks.

“There is no doubt that contents of today's chemistry sets are far tamer than they were a few generations ago”, says Al-Gailani. But he is not convinced that this is the only or even main reason behind the much lamented “decline in popularity of the chemistry set.” To understand that, he says, “we need a much better understanding of wider shifts in the toy industry, especially the perceived profitability of scientific toys, and the place of chemistry in popular culture.” He thinks that the perception that the chemistry set should play a role in drawing children into science “has a lot to do with the iconic status of the chemistry set in writing about scientific careers and nostalgia for a less risk-averse era” – that it’s a story we tell, but not necessarily the right or complete one.

Smells and stinks

The chemistry set today is rarely marketed with the sobriety of the past. It emphasizes science as fun – smelly, disgusting, tactile and visual. We will surely one day be judged for this, for better or worse. There are certainly dangers in suggesting that chemistry is going to be relentlessly fun and entertaining, selling itself on stinks and bangs, as UCL chemist Andrea Sella argued when accepting the Royal Society Faraday Prize for communicating science this year.

But those sensual delights are harder to procure anyway when the range of chemicals permitted in a chemistry set is constrained. One alternative – some will see as a poor one, lacking the true tactile and aromatic sensations of chemistry – is the CHF’s Chemcrafter app, tellingly displayed in a 1950s visual style.


The chemistry set of the future? The Chemcrafter app from the Chemical Heritage Foundation.

Yet the questions confronting manufacturers now are in some ways not so different than ever they were. Should chemistry be made to feel exotic or familiar? Are chemistry sets about fun or sober instruction, and how far can the two be combined? Should they be marketed at the children (and which children?), or their parents? Whatever answers we find will say a lot about us.


Totally gross: chemistry sets today.

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Box: What’s in the Box?

In circa 1915, the British Lott’s Bricks Chemistry Set No. 5 contained the following:
“Alum powder, ammonium carbonate, ammonium chloride, borax, calcium carbonate, charcoal (powdered), Congo red, copper sulfate, iron filings, iron sulfate, lime, manganese dioxide, potassium bichromate, potassium permanganate, potassium iodate, potassium iodide, potassium nitrate, “Sky blue”, sodium bicarbonate, sodium bisulfate, sodium carbonate, sodium nitrite, sodium thiosulfate, strontium nitrate, sulfur and zinc.”

In 1965 the Skil Craft Chemistry Set contained these ingredients:
“Ammonium chloride, gum arabic, cobalt chloride, sulfur, calcium chloride, sodium silicate solution, phenolphthalein solution, tannic acid, sodium ferrocyanide, manganous sulfate, sodium thiosulfate, ferric ammonium sulfate, sodium salicylate, borax, sodium bisulfate, and aluminum sulfate.”



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References
1. M. Keene, Ambix 60, 54 (2013).
2. S. Al-Gailani, Stud. Hist. Phil. Sci. 40, 372 (2009).
3. J. C. Burnham, J. Soc. Hist. 29, 817 (1996).

The Chemical Heritage Foundation’s exhibition Science at Play: 100 Years of Chemistry Sets and Science Kits runs from October 2015 to September 2016 in Philadelphia.