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Wrapping ideas and spectacle into the perfect Christmas present

A few years ago, I demonstrated the science behind buoyancy by attaching helium-filled balloons to a teenage girl and floating her off Alexandra Palace in north London. “It was boring,” she said, on returning to earth. “All we did was fly.”

Kids, eh? In the age of Harry Potter and the Xbox, it can be hard to thrill with mere reality. And yet the world’s increasingly synthetic nature has also created an appetite for unmediated experience—think of how attendance at live music has boomed as record sales have collapsed.

This is a hunger that educators of all stripes should be tapping into. When done well, there’s an immediacy and directness about a lecture that makes it the perfect vehicle for kindling insight.

That’s particularly true of my science, chemistry, because no other discipline is so suited to live performance. MRI images and telescope pictures are amazing, but there’s a machine between the viewer and the thing. There’s nothing like a chemical reaction for linking a scientific concept to a physical phenomenon.

In the spring, I learned that I was on the shortlist to give the Royal Institution’s Christmas Lectures. Ever since, my mind’s been whirring, thinking about the ideas I want to communicate, and the demonstrations that will convey them.

The RI asked me to prepare a proposal on the subject of the elements. It seemed a disappointingly stale topic. But the more I thought about it, the more excited I got. People know about the elements, but they often misunderstand them—this was a chance to really educate.


Given that I only had three lectures, I went back to the Greek idea of the elements, devoting one to each of earth, air and water. That left no room for a talk devoted to fire, but pyromaniacs can rest easy: no lecture will lack for combustion.

I also had to do a screen test. I decided to show how water expands when it turns to steam—the transformation that powered the industrial revolution and still generates most of our electricity. I used a transparent piston made of silica, which is heated to 300°C so that when you add a millilitre of water it evaporates more or less instantly.

It’s a beautiful thing and it must have done the trick, because in June I learned that I’d got the job. Since then, I’ve been throwing ideas at the RI and the BBC, who will screen the lectures. They have helped winnow the material and shape it into a narrative, while I’ve occasionally had to point out that the amazing thing somone saw on YouTube is not actually chemically feasible.

As of the last week of November, I’ve been in rehearsals full time, building and testing the demonstrations ahead of the first lecture on 11 December. On the day, there’ll be some capacity for retakes, but to pretend nothing ever went wrong wouldn’t be true to the science—and besides, audiences rather like a mishap.

There’s an art to creating a demonstration that entertains and amazes but also makes a point. It takes a long time to design and build the equipment—that silica piston took years, and eight or ten prototypes, to get right. But beyond that, it’s taken me years to understand how to package the idea inside the spectacle, so that it seems obvious. At its best, it’s almost as if the audience hasn’t realised that it’s learned something.

Chemistry, of course, is the science most closely associated with the RI. We’ll be nodding to the past—to the work of Humphry Davy, for example, who showed that sodium and chlorine were elements.

But if you thought that chemistry demonstrations hadn’t moved on since your schoolteacher lit up a magnesium ribbon, think again. We’ll be trying things that have never been filmed before. The Christmas Lectures are big shoes for any chemist to try to fill, but I think Faraday himself would be impressed by some of what we’ve got planned. We might even prompt a jaded teenager or two to raise an eyebrow.

The web has given the lecture new life. By fuelling the rise of geek culture, it’s made it more fashionable to be interested in ideas. And it’s shown there’s a huge audience for watching people talk about them, as illustrated by TED talks and by the RI Channel.

I’m fantastically lucky that these days, the Christmas Lectures give their presenter the best of all worlds—the chance to engage with a live audience, the chance to reach a mass audience on TV, and the chance to be viewed at any time by anyone with an internet connection. Now all that I need is for the equipment to work.

The Christmas lectures will be broadcast on BBC4 at 8pm on 26, 27 and 28 December. Photo: Paul Wilkinson