Some 1600 years ago, as an alchemist was once again trying to find the secret of immortality, the furnace he was working with suddenly exploded, and he was seriously burned. But the accident eventually led to another Chinese invention － gunpowder.
一千六百多年前，當煉丹道士在鑽研長生不老的藥時，煉丹爐曾有一面忽然爆開，火舌猝不及防地撲上道士的臉和手，煉丹發生了意外，也使中國發明瞭：火藥。火藥是在晉朝時被煉丹術士偶然發現的，他們由經驗得知，某些藥物化合，就會引起燃燒爆炸。