Fireworks have always been a source of mystery and nostalgia for many people. Perhaps its because we are generally introduced to these noisy and colourful displays when we are young and at a most impressionable age, after all being allowed to stay up late and go outside in the dark with the adults is pretty exciting stuff for a 4 year old. For me fireworks started with a few sparklers and the dads lofting up some bottle rockets. I then progressed to the larger, but still modest, shows held by the PTA at my local primary school.
In Japan fireworks, or “Hanabi”, are in a different league and are taken very seriously. Every summer usually around late July hundreds of major displays each with tens of thousands of explosions draw huge crowds. Fireworks in Japan have evolved technically over the generations into far more complex aesthetic endeavours than what I ever saw when I was child.Part of the reason that fireworks in Japan are so advanced maybe because they are seen as much a form of entertainment for adults as for children. In the past they were the exclusive domain of the upper class, rich daimyo’s would gaze at them as they floated on river boats, eating and drinking delicacies and being entertained by geishya. These days some of the most spectacular shows are the Hanabi Taikai, or competitive events where teams of pyrotechnics from around the country come together at live televised events to be judged on their technical and artistic merits.
At this level, fireworks no longer resemble the cylindrical rocket shaped crackers with a stick poking out the bottom, they are spheres made of papier-mâché and string pasted together. Inside the shell ‘stars’ are packed in with black powder to help ignite them. A firecracker-like bursting charge is inserted in the middle of the shell, and a fuse attached to it from outside the shell. If you’ve ever seen one of these shells up close or handled one the first thing that will impress you is the weight, they are almost completely filled solidly with powder and with diameters ranging from about 7 cm to well over a meter they can weigh up to and beyond 400Kg a piece!
The shells are launched through huge mortar-like tubes , up to 30Kg of black powder is needed to shoot the larger shells up to their explosion elevation of about 600m. To make the display last as long as possible, firework-makers have learned to use the largest grains of black powder in their stars as possible, and not to mix the powder’s ingredients too thoroughly. That way, the fuel inside the stars gets starved of oxygen slightly, making the combustion leaner, brighter and last longer.
While the Chinese remain the world’s largest producers of commercial fireworks, the Japanese have some of the most sought-after designs. Manufactures have an arsenal of various techniques they draw on to wow the crowds, such as pressing their stars, onion-like, with separate layers containing different colouring agents—so the display can change colour as the stars burn. And while the spherical design is also used elsewhere, the Japanese trick that foreign firework-makers have yet to master has more to do with the manufacture of the shell itself rather than the ingredients that go into it.Thanks to their paper making traditions, the Japanese know better than most how to paste layers of paper on the shell’s surface and how to dry the shell so its strength balances the explosive power of the firework’s bursting charge precisely.
I’ve come a long way since my sparkler days, but thanks to the amazing skill of the Japanese at this art form fireworks still have that magical quality they always had. What’s your favourite Hanabi Taikai? Tell us in the comments.