Gunpowder

Gunpowder became known in the West about the middle of the thirteenth century. The Franciscan scientist Roger Bacon mentioned it as something already widely known; this is his description of a firecracker:

“There is a child’s toy of sound and fire made in various parts of the world with powder of saltpetre, sulphur and charcoal of Hazelwood. This powder is enclosed in an instrument of parchment the size of a finger, and this can make such a noise that it seriously distresses the ears of men, especially if one is taken unawares, and the terrible flash is also alarming; if an instrument of a large size were used, no one could stand the terror of the noise and flash. If the instrument were made of sold material, the violence of the explosion would be much greater.”