A long long time ago, or in fact a few drops of pitch ago, I was a med student at the University of Queensland. Our first-year course included physics – same lecture theatre every time, and that meant repeatedly walking past the cabinet containing what was to become one of my favourite physics experiments.
You don’t have favourite physics experiments? Your loss. And don’t go telling me you got a life instead.
Whatever life you get yourself, it’s not likely to outlast this experiment. And that’s one of the things I like about it. Whether or not it was meant to be about this in the first place, now one of the things it’s about – for me anyway – is slowness. And it’s a great reminder that all in the world around us might not be as it seems, and that it can pay to look more closely, and not live entirely by assumptions.
In 1927, Professor Thomas Parnell poured pitch into a funnel, gave it three years to set and then inverted it and clipped off the bottom. And then nothing happened, right? Because pitch sets solid.
Actually, no. it doesn’t. It might shatter if you hit it and we might use it to build roads, but it’s not solid – at room temperature, it’s a liquid with a viscosity about 100 billion times greater than water. Which means it flows. V e e e e r y s l o o o o w l y.
I love the experiment’s simplicity and its understated ambition. It’s just pitch in a funnel, but it’s two century long. It feels like the university declaring, while only in its teenage years, that it was here to stay. Maybe that’s in my mind rather than Prof Parnell’s, but maybe not.
I’ve always felt an attachment to it, and it seemed natural when sending Jon, my central character in Perfect Skin, to give Ash a tour of the campus, that it was one of the things he’d point out. So it ended up in the novel. And that part of the novel is now, I’m proud to say, part of the pitch-drop experiment. The text is reproduced in the cabinet.
Today I visited the pitch drop again, this time with Thomas Parnell III, grandson of the prof, and Professor John Mainstone, custodian of the pitch drop since 1961, my physics lecturer in 1981 and father to one of my fellow med students.
The pitch drop is suddenly back in the public eye because drop nine is about to fall. And this time we can all be in on it. No fall has ever been witnessed, despite the hours Prof Mainstone has put in, and despite the technology used last time. This time, Prof Mainstone is planning to leave nothing to chance, with three webcams in action, with separate power sources.
If the Guinness Book of Records had a category for slowest live streaming event in history, it would go to this page, where you can watch the pitch drop hanging tantalisingly and, perhaps, soon, watch it fall.
Part of me wants this drop too to evade us and keep the tradition going, but most of me wants Prof Mainstone to have his day. After 52 years, the man deserves to see it, and to glean from it something we don’t yet know about the science of pitch and extremely high-viscosity liquids. He has ideas about how the drop might separate, but none of us knows, yet. It turns out there is actually some physics at stake here. I might see metaphors galore in this thing, but it’s still a working science experiment.
So now’s your chance to be part of history. Some time soon it’ll fall and UQ is waiting for the first person to declare themselves a witness to it. Who wouldn’t want that on their CV?
After that, and a quick beaker change by Prof Mainstone, we can all relax until around 2026, when we get to do this all again.
Here’s how it appears in Perfect Skin, between drops seven and eight:
‘Let me show you my favourite thing here,’ I say to her, as though I’ll win the hand by playing an ace. ‘Well, maybe that’s creating a bit much of an air of excitement, but come and see it anyway.’
I take her across the Great Court, to the Parnell Building, to the display case just inside the door. The pitch experiment set up in the twenties by the university’s first physics professor. He mixed the pitch and sealed it until it cooled and was apparently set, then he upturned the funnel and began a 170-year demonstration that pitch isn’t solid. That it looks completely hard, but it’s still viscous and flowing. In the experiment it drips out of the bottom of the funnel, but years pass between drips.
‘I got my whole degree between the third last and the second last,’ I tell her. ‘It often falls on weekends, and no-one’s ever seen one fall. For the last year or so, it’s been about to go.’
‘So what was he thinking?’ Ash says. ‘He knew his physics. He must have known his great-grandchildren wouldn’t see the end of this experiment.’
I hold the Bean up to the glass, and she slaps it with her hands, and makes a noise that says she knows there’s something going on. Something in the case that I think’s worthy of attention.
‘So was that to demonstrate the virtues of patience? Showing me this?’
‘No. I’m not a demonstrator of virtues. It was me showing you something I liked.’
‘Good. I like it. It’s sort of like a very slow black lava lamp.’
‘This was about the speed Professor Parnell liked his lava lamps, I hear. The sight of grass growing used to really trouble him.’