Gunpowder
Gunpowder was invented by the Chinese in the eighth century AD.Early Chinese scientists discovered that they could make an explosive substancen by mixing sulphur,charcoal and saltpeter. Gunpowder was used in warfare and led to the development of many different kinds of weapons. For example, rockets carrying an explosive shell of gunpowder could be launched at enemy soldiers from a bamboo tube.
The Compass
The ancient Chinese noticed that certain kinds of metals, like iron ore, usually aligned themselves in a north to south position.
By the third century, they had started making the first, simple compassesby floating small pins of magnetic metal in bowls of water. By the eleventh century, the Chinese were using sophisticated compasses to navigate their ships at sea. In the West magnetism was not discovered until the fifteenth century. Until this time, European sailors were still navigating by the stars.