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Carriacou Diary: Jonathan Hare

Day 28 — Fireworks

Awoke to a cold today so feeling a little tired and run down. This morning Mike B and I discuss the plan for our part in the next three days of filming. On the odd moments of rest during the day Mike seems v. tired and far-off. The plan is that Mike B will make the basic ingredients for the gunpowder today while I will make some scales to measure out the ingredients and also an electronic ignition/detonating device so that we can safely set the fireworks off.

Jonathan explains the physics involved in fireworksGunpowder has three main ingredients: salt peter (potassium nitrate), sulphur and charcoal. The charcoal is made by burning wood with limited air so that it carbonises rather than forming carbon dioxide and burning. The sulphur was given to us. Mike B made the salt peter in an amazing and wonderful way. It's great when you can get such an important thing from crap — and that's exactly what he did!

The finely granulated gunpowder components are to be mixed in exact ratios. As the ratios are fairly simple ones, it is easy to construct a simple set of scales for measuring out the quantities using a balance system of pans and different positions on the scale balance arm. In this way you don't need to measure the exact weight of each ingredient, just the exact ratio of weights between them.

Mike B not well in the afternoon and stays in bed. I made up a very large detonating plunger (like ones you see in the films for detonating dynamite!) which was simply a switch but looked the part! This was used to send power to a wire that would run along at some length to the firework. At the end of the wire was fixed a small amount of very thin wire which, when the switch was pressed would glow red hot, burn out and set light to the powder/firework.

Kathy, Mike L and Ellen start to make up their musical instruments. We all seem to be working in the same area this time and so I can actually get to see what they are doing. With the other programmes I won't see what they had done until it is shown on TV!

Kathy talks about the maths of a resonant column of air with which she can calculate the size required to give a specific musical note. In principle, by blowing over a piece of pipe cut to the correct length one can get the correct note. Mike L has an interesting idea. He tries to use the air flow caused by the updraft from a candle to 'blow' the tubes and produce the note. He cuts up some heavy steel tube and tries them out on the flames. The suspended tubes sound wonderful when they are hit but really weird when flames run! Quite magical though with all the sound, fire and smoke. These experiments seem to cheer him up though as I don't think the music challenge would be his first choice. I was told by one of the locals that when he was young they used to make model sailing boats and they used to fix a lighted candle into the boat and make use of the draft to power them along.

I try out the detonator with pieces of thin wire to show that it glows — Kate seems to love the idea and has a cartoon-like expression of power when she presses that plunger! I also make up a five-way switch which might be useful to move from one firework to another on the last day.

Day 29 — Fireworks

Today needs to be gunpowder-making day and Mike B is on the case. He actually makes it from wee-soaked soil. The bacteria in the soil apparently forms nitrates (eventually to be salt peter) which can be extracted. He makes his first batch of salt peter which not only crystallises but when a piece of paper is dipped into it and dries, acts as blue touch paper! A really great piece of chemistry and done on TV too!

Jonathan working on the fireworks Mike B and I need to fill in COSH safety forms. Angie makes up batches of gunpowder after Mike has shown that it is possible from scratch. I make up a 'blasting' extension lead so that we are as far as possible away from the fireworks when they 'go up'. We have a meeting about safety and then we all get together to decide on what piece of music the 'band' will play with their instruments.

In the afternoon I start to make up bangers (squibs, thunder crash, call them what you will!) and experiment with various different designs. Mike B, Kate and I have fun testing these out — in old military-style fashion! The first one fizzed and wheezed a bit, the second made a good bang, the third after a delayed start was loud. In fact they were so loud that the soundman was unable to record them! So we had to make another couple of test runs just to make sure he could record them! Mike B makes up a Roman candle for testing but it does not work. Find out that it was made from a new batch of gunpowder which was a little damp. The humidity here is a problem as is the torrential rain that falls every few days if only for a few minutes.

My cold has fully come out, nose streaming all day. I feel tired at nights but in the day the adrenaline keeps me going I think.

Day 30 — Fireworks

Get up at 5.30 as usual. Last night I slept straight through — the first time since being here. I think it was the Beechams Powders I took. Still very tired though, so after breakfast I go back up to my room and have a lie down. I think I must have fallen asleep because when I get up next the hotel is very quiet. I go downstairs and there is no one around — the buggers have gone without me!

Kate tests the detonating deviceStart to walk the 1/2 mile or so to the lime factory and eventually Sandra comes up in the 4 x 4 and picks me up. Go into town to collect a few provisions and then head back to the factory.

Day starts by making up four bangers (well, five but I had to test one!) and then working with Mike B and Angie to try and make best use of the time and powder available. Start working on the rockets while Mike B works on the Roman candles. Do a couple of tests on the Roman candles which went really well, considering they were in the sunlight too! Drew gets some amazing camera footage of the rockets taking off — great! (he was very pleased also).

After lunch and a safety talk, gloves and face goggles are put on and we all get together to make up as many fireworks as possible. I ask Mike L if he can make me up a Catherine wheel from one of the spare rockets. By the end of the afternoon we have about 8 Roman candles, 6 sparklers, a Kathy wheel and two rockets. Mike B starts to set up troughs made of bamboo to fill with alcohol (rum) to form a burning backdrop and frontdrop to the bonfire session. Ellen, Kathy and Mike L set up the band nearby.

Jonathan talks pyrotechnics with the two MikesAs the evening light faded the most weird weather started to come in. We had reports that a tropical storm was in the area off Grenada and I think we were lucky that we missed the worst of it but now the tail ends were rolling around. The sky went an amazing pink-red colour instead of becoming dusk. Where the sun was setting blue sky could be seen and every so often lightning flashed about — totally surreal!

When it was dark enough the band played the tune — Ode to Joy and then Mike B and I started the fireworks. The Roman candles and the rum-filled bamboo gutters were spectacular and amazing. Some of the candles were lively enough to start off their neighbours without Mike B having to light them. The sparklers worked well but my rockets failed to light even with a sparkler right up the middle! The Catherine wheel was a great surprise and worked like a dream, I was so happy for Mike L. In the end Angie knocked up a super duper little rocket and we ended on a high with a dog-legged trajectory!