Say Bonfire night with flowers?

Bonfire Night is upon us and it’s one of the busiest nights of the year for us pyros. I get to spend the best part of a week working knee-deep in mud and living out of a van. However, for the discerning pyrotechnician, creating a fireworks display is a real science-art mash-up in which the night sky becomes our canvas.

We use science to entertain huge crowds. We fire colours and effects in different parts of the sky and at various heights. We use a range of effects and pace to create a contrasting and stunning sequences. As a scientist and a performer, I love all this. I love the fact that I can be creative by using some pretty fundamental bits of science.

So with this in mind, when I was approached by Interflora to help create a world first – a fireworks display made from real flowers… well, you would, wouldn’t you?

Sounds crazy? Actually, there are some very logical links. Firstly, creating a firework display is not dissimilar to arranging a spray of flowers.The way a florist balances colours and creates patterns in the bouquet.

Multi-coloured peony aerial shells.

In fact, several firework arrangements are known as bouquets. And it’s not without coincidence that there has long been a historic connection between fireworks and flowers with many of our most popular aerial effects, such as peony, dahlia and chrysanthemum, also being the names of everyday garden flowers.

The aim of the project was literally to turn history on its head, with flowers exploding to look like the fireworks that are named after them.

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The footage looks impressive, but in order to achieve what we wanted there were a number of questions we needed to answer. Firstly, we didn’t know if creating this display would even be possible; would the delicate petals burn, be scorched or shredded by the burst or lift charges? The rapid acceleration could damage them. And if they did survive the pyro, would the petals flutter or hang in the air long enough to look like a real firework display to the naked eye?

Petals are really delicate and so to achieve these results we couldn’t use anything too powerful. For example, a CO2 blaster or a “mine” effect could rip the petals apart.

With a bit of experimenting, a team of pyrotechnicians, lighting technicians, a camera crew and a super slow motion camera, we got there.

And in true Tosh-style, here’s the ‘making of’ video:

Exploding petals isn’t footage I’d ever seen before, but it worked! It looks cool and is most definitely a quirky take on the firework-flowers link. I hope you like it.

There’s more information about the project on the Interflora website.

Live stream presentation

Regular followers of my musings and Twitter posts will know that I love live events. It’s what I do in addition to presenting. Last weekend, I presented the live broadcast of the National Twelve Bell Striking Competition. Yes, it’s a rather niche event, but amongst the 30,000 or so campanologists out there, it’s the equivalent of the world championships (despite the misleading title).

At just-under seven hours, it’s the longest live session I’ve done and I’ve received mountains of positive feedback since.

The podcast files can be found here.


Bangs for the sake of bangs?

I was prompted to write this article in response to a number of comments on social media channels in the past 24 hours about pyrotechnics and explosions in chemistry outreach and science communication activities.

In case you’ve just arrived from an external site, I’ll declare my interest at the outset: I am a pyrotechnician as well as a science presenter. I am a physics graduate, not a chemistry graduate, but I use chemistry and rely on it in a lot of my work. I should also add that I broadly agree with the arguments against explosions for the sake of explosions – chemistry is far more elegant and a much broader subject and one shouldn’t attempt to represent it by a single type of demonstration… or a demonstration at all, as some may argue.

I do not wish to reduce the debate to “are pyrotechnics and explosions per se good or bad?” A little of everything in moderation and used appropriately, works well. By appropriate, I mean not including a bang just for a cheap audience thrill and “getting them on side”. I’ve seen so-called “whizz-bang” lectures that are a cluttered collection of exothermic, brightly-flashing, smokey reactions with little or no structure and, quite frankly, they bore me. I’ve also been fortunate to see some very clever lecturers and teachers build suspense, with even some of the quietest of demonstrations (the first time I saw Nylon being made springs to mind).

The challenge of a presenter or lecturer is to present a broad range of demonstrations representing different aspects of the subject. This is true for many subjects and not just chemistry.

However, I am concerned at some of the paraphrased comments and questions I’ve seen flying around on social media networks today about how pyrotechnics could be perceived as a “terrible tool for chemistry outreach”.

Pyrotechnics and pyrotechnic-type demonstrations (including explosions and stoichiometry demonstrations) cannot and should not be used as standalone representations of chemistry. It’s far too narrow an application. I think most people would agree on that. But let’s not forget that they do indeed represent valid and real applications of chemistry. I know post-doc chemists who have worked in pyrotechnics R&D and I spend a lot of time in muddy fields using their products.

Pyrotechnic devices (as we call them in the industry) are tools. Any tools or devices can be used correctly, but they can also be misused. Misuse could be downright dangerous or irresponsible use (e.g as a weapon). It could also be including a bang or flash in a lecture for the sake of it because it’s chemistry and that’s what the audience expects to see. Overuse is a misuse.

Audiences expect it because over the years we’ve allowed the bangs to become the main stars of our demonstrations and have hence allowed the perception to develop.

I am regularly asked to present lectures about the science behind professional firework displays and stage effects. My area of interest is how both chemistry and physics underpin the range of visual and aural effects, not to mention how we make it all happen with technology, engineering and maths. I’m absolutely clear from the outset that I’m presenting a very specific application of the sciences. The main aim is to highlight how Science, Technology, Engineering and Mathematics (STEM) play important roles in the creative and entertainment industries – pyrotechnics being just one aspect of this broader industry.

Matthew Tosh demonstrating an application of chemistry

© Matthew Lord 2013 |

In most of my lectures, I only include one actual explosion and its primary purpose is to demonstrate a physical principle; i.e. that of a supersonic shockwave. Yes, it’s loud and the maximum pressure is selected to match the size of the venue and age of the audience. I won’t lie; it’s a great demonstration and I really enjoy doing it. It usually features in a series of demonstrations relating to reaction rates and rates of energy release. However, if I’m not doing anything about shockwaves, then I rarely include an explosion.

The colour chemistry can get very detailed, depending on the age of the audience I’m talking to. It’s a great way of demonstrating aspects of physical chemistry, electron energy levels and competing emission spectra. Pyrotechnic whistles are fascinating, but bizarrely illustrate more physics than actual chemistry.

I’m trying not to sound too defensive. I am obviously biased towards pyrotechnics as I’ve been working with them for over seven years. My passion for them is driven by the fact that there is a wealth of chemistry and physics at play behind the scenes.

Chemistry cannot be communicated with pyrotechnics alone, but to badge them broadly as a terrible tool for chemistry outreach is misleading.

If deploying carefully selected pyrotechnic effects and demonstrations helps open a young person’s mind to some of the possibilities and wider applications of the STEM subjects and why it is important to get a good GCSE grade (or equivalent) in these subjects, then I will have achieved my aim as a science presenter.

A terrible tool? I’d argue that it is the operator who is at fault, not the tool.