Great Song chemical incendiary manuals circulate

1247

Song military writers compiled the Wujing Zongyao and related texts with recipes for gunpowder mixtures, fire arrows, and flamethrowers. The manuals represent the earliest detailed gunpowder literature anywhere and mark the transition from alchemical curiosity to battlefield practice. The formulas described varying ratios of saltpeter, sulfur, and charcoal for different effects, from smoke screens to incendiary projectiles to crude explosive bombs.