Splattering Cream across Tradition

The Royal Institution is a venerable organisation: dating back to 1799, it is situated in an amazingly impressive building on Albemarle Street in London. This was the road that became the original one way street in order to cope with the press of carriages depositing the eager public, who turned up to listen to the likes of Humphrey Davy and Samuel Taylor Coleridge give public lectures during the first years of the nineteenth century.

My first experience of the building was as an 11 year old, when I was fortunate enough to be given a ticket to the Christmas Lectures, given that year by Desmond Morris on Animal Behaviour. Hearing him did not turn me into a Zoologist, nor even make me determined to be a scientist of some other hue, but it certainly has stuck in my memory ever since (although I wouldn’t like to take a test on what he said) and I’m sure it involved a chimpanzee at some point.  Much more recently I used to watch the lectures with my own children on TV, and I have an abiding memory of watching my friend and colleague Tony Ryan, who gave the lectures in 2002 on Smart Stuff (ie soft matter, polymers etc) being chased round the lecture theatre by a penguin, although why he had a penguin there to do the chasing escapes me.

I’ve been in the building at various times over the years. It was the venue for one of the IOP’s Schools Lectures back in 1996, which several of us (Richard Jones, Ruth Cameron, Adrian Rennie and I) took around the country, the RI being one of the easier venues to reach from Cambridge. For the lecture we had a well-honed set of demonstrations, as we discussed polymers under the title of Building with Snakes; some of these demonstrations are still going strong.  Subsequently I’ve been there for various meetings, discussions, L’Oreal For Women in Science Awards and, most recently, for a discussion with David Willetts and Jenny Rohn in a debate hosted by Evan Harris, which took place in one of the elegant rooms on the ground floor.

Last week it was my opportunity to give one of their famous Friday Evening Discourses  –  lesser events than the Christmas Lectures, but requiring me (and the audience) to don evening dress and (just me) to produce a slew of demonstrations. It is no mean challenge to set up a series of demonstrations swiftly in that iconic lecture theatre, now equipped with purple plush seats, a great deal more comfortable than the hard wooden benches I recall from my first visits. To perform these experiments in a long gown just seems asking for trouble, but at least the RI kindly provided me with a white lab coat (albeit rather large) to protect my clothing. I think that was just as well.

The topic of my talk was Goo, and I definitely had plenty of messy stuff to get my hands stuck into and with which potentially to splatter my clothes. It is a topic that lends itself well to demonstrations to non-specialists, and I had little idea in advance what to expect of my audience. To be told it would consist of ‘members’ was not particularly informative (since anyone can pay their dues and become a member) when it comes to assessing what level of knowledge can be assumed. In the end, my audience may not have ranged quite from 8-80, but certainly from about 10 to over 70, and there was a group of 10 or more 6^th formers – I never gathered from which school – who were indeed in black tie as required (and a suitable dress for the solitary girl that I spotted amongst them).

Goo is not only good for sticky demonstrations, it also allows me to discuss some basic polymer physics and in particular polymer chain motion, known as reptation, as developed by those ‘inspirational gentleman’ Pierre-Gilles de Gennes and Sam Edwards I wrote about before. The way polymer chains move, entangle and so affect viscosity not only offer varied opportunities for entertaining show-and-tell, but also have important consequences for practical matters: the role of polymers is crucial in thickening up water for manufacturers to sell in more sophisticated forms – shampoo, cosmetics, manufactured foods etc.  In other words, reptation lies at the heart of homely matters such as why shampoo doesn’t simply fall straight off your hair.

Sam Edwards once moaned to me about the fact that Unilever was celebrating his theoretical ideas at their research centre – with a large poster about the toilet cleaner Domestos, which (as you will recall from the adverts) clings for longer than other brands. He felt being remembered for helping Unilever understand the way to go about thickening up a toilet cleaner was perhaps not the best claim to fame. Another scientist who also played his role in the story of reptation started off in the field of cold atoms – for which he won the Nobel Prize in 1997 – and ended up as Obama’s Energy Secretary. This was Stephen Chu who, in 1994 published the set of experiments which allowed the first direct visualisation of reptation, by using optical traps to twist and tie long fluorescently-labelled DNA chains, which then slowly unwound so that their trajectory could be directly imaged.

Goo as a topic, also allowed me to sneak in a bit of biological physics in the form of spider silk (have you seen this gorgeous example of what you can do with the silk from 1.2 million golden orb spiders?) and what  happens when you denature proteins by mechanical energy in the form of making a meringue from egg whites. At this point I moved on to real ‘cookbook’ stuff, separating the whites of several eggs and giving them a good whisk. It was as I moved on to whipping the cream that the goo really flew – as Gail Cardew (Director of Science and Education at the RI) remarked, she was glad she was sitting in the 3^rd row. I didn’t see the young, bow-tied youth in the front row and therefore in direct line of sight and cream, quail or flinch as I whipped away. Clearly he was made of sterner stuff – and still had the courage to ask me a question about snot at the end.

It was an interesting evening from my perspective, and I hope from the audience’s too. I was impressed by the wide-ranging questions (from plant science, to polymer characterisation, to snot, to the future, to cooking and to my personal research activities), not to mention exhausted by their enthusiastic curiosity at the end of a long day, during which I had also attended Anniversary Day at the Royal Society (where I attended their Council in the morning, having recently been elected back onto it). I have two regrets about the evening. Firstly, that I wasn’t given more time and opportunity to look around the building, its artwork and its archives, which are clearly fascinating.  And secondly, that the RI’s strong sense of tradition still requires formal evening wear – which seems beyond anachronistic when attempting to demonstrate science – and entails various ancient rites, such as that the speaker mustn’t start off their talk by saying ‘Good Evening’. I found this instruction merely made me unable to think of any other way to get going, in the way being told not to talk about gorillas makes all other topics vanish from the brain, and the directive certainly served to increase the butterflies in the stomach as I waited outside the lecture theatre for the clock to strike 8pm and the doors to be ceremonially opened.