they have invented the compass, paper, porcelain and silk cloth and the abascus, junks, canal locks, paper money, playing cards, printing devices, gunpowder, hello kitty, computers, china, rockets,...
In 9th century china when a cook mixed potassium nitrate, also known as saltpeter, sulfur, and charcoal. Instead of burning it exploded, so it was used to make fireworks, which explode.