Greek fire
The impression made by Greek fire on the western European Crusaders was such that the name was applied to any sort of incendiary weapon, including those used by Arabs, the Chinese, and the Mongols. However, these mixtures used formulas different from that of Byzantine Greek fire, which was a closely guarded state secret. Byzantines also used pressurized nozzles to project the liquid onto the enemy, in a manner resembling a modern flamethrower.