Gunpowder

Gunpowder, also known as black powder, is the earliest known chemical explosive. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpeter). The sulfur and charcoal act as fuels, and the saltpeter is an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks. Formulations used in blasting rock (such as in quarrying) are called blasting powder. Gunpowder is obsolete in modern firearms, but is still used in antique firearms because modern propellants are too powerful and could break the already fragile barrels.

Gunpowder was invented in the 9th century in China, and the earliest record of a written formula for gunpowder appears in the 11th century Song dynasty text, Wujing Zongyao. This discovery led to the invention of fireworks and the earliest gunpowder weapons in China. In the centuries following the Chinese discovery, gunpowder weapons began appearing in the Muslim world, Europe, and India. The technology spread from China through the Middle East or Central Asia, and then presumably into Europe. The earliest Western accounts of gunpowder appear in texts written by English philosopher Roger Bacon in the 13th century. The hypothesis that gunpowder was used by ancient Hindus was first mentioned in the eighteenth century by some Sanskrit scholars. The most ardent protagonists were Nathaniel Halhad, Johann Backmann, Quintin Craufurd and Gustav Oppert. However, due to lack of sufficient proof, these theories have not been widely accepted.

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