Kami-Seinaiji, Achi Village, Nagano Prefecture

　Seinaiji has passed on the tradition of “wabi” (Japan’s traditional fireworks) through handmade fireworks that have now decreased in number. National Theatre Okinawa has recreated five units of karakuri fireworks but the fireworks used were not “wabi.” Fireworks of the Ryukyu Kingdom and the Edo period were made of (1) potassium nitrate, (2) sulfur, (3) charcoal, and (4) iron powder. The color and momentum are changed by changing the composition. Because iron powder in particular makes fireworks burn longer, when it is used in fountain fireworks, sparks fly up high and fall on the ground without dying out, creating fountain-like long trajectories..
　However, since iron powder is rust-prone, it has to be made in the morning and used on that evening. Since we couldn’t make them ourselves because there is no firework factory in Okinawa and gunpowder cannot be transported by air, we couldn’t use fireworks made using iron powder. That is why a karakuri mechanism was sent to Nagano Prefecture in October of 2024 to mount fountain fireworks made in Kamiseinaiji on to it and to conduct a combustion experiment. Although the mechanism was hidden by smoke because the day was windless, the fireworks drew soft, beautiful curves like in the drawings in the Hibanahou Nikki.