The answer is the magnetic compass and gunpowder.
The magnetic compass and gunpowder were first developed under the rule of Chinese dynasties.
In fact, the compass and gunpowder were identified as part of the FOUR GREAT INVENTIONS OF CHINA. The other two were paper making and printing.
The magnetic compass was greatly used throughout Chinese history. They would use a magnetic needle that would be place floating in bowl of water. The magnetic needle was called ""south-pointing fish" because it aligns itself to the south.
The gunpowder was discovered in the 9th century but its explosive potential was perfected in mid-14th century.
