Was Gunpowder Invented on Purpose?

For centuries, Chinese alchemists had been mixing various compounds, looking for an elixir that would unlock the key to eternal life. At some point during the late Tang dynasty, around 850 AD, these alchemists mixed saltpeter -- the oxidizing agent known today as potassium nitrate -- with sulfur and charcoal, and accidentally discovered gunpowder. Their explosive invention led to the creation of new and highly effective weapons, from fiery arrows in the early days, to the later development of rifles, cannons, and grenades. Gunpowder has also been used over the centuries for non-military purposes, such as fireworks for entertainment, and in explosives used in mining and tunneling.

An explosive discovery:

• The Song dynasty (960–1279 AD) is known to have beaten back invading Mongols with “flying fire” -- arrows fixed to tubes of gunpowder that were ignited and sent rocketing across enemy lines.
• The Mongols also felt the sting of more advanced gunpowder-based weapons over the following century, as the Chinese perfected the first cannons and grenades.
• Gunpowder remained something of a secret weapon for the Chinese until the 13th century, when the science was passed along the ancient Silk Road to Europe and the Middle East.