The four great inventions of ancient China include "movable type printing", "papermaking", "gunpowder" and "compass". What is related to Tianshui should be "papermaking" and "compass". Tianshui City is located in the southeast of Gansu Province. From June to September 1986, archaeologists from the Gansu Provincial Institute of Archeology visited the Western Han Dynasty Tomb in Matan, Tianshui. A geological map was excavated. The paper is 5.5 cm long and 2.6 cm wide. This newly discovered paper map of the Western Han Dynasty is the earliest paper object currently known. These are strong proofs that ancient China invented paper that could be used for writing and painting in the early Western Han Dynasty. The existence of papermaking was confirmed.

There is also a famous saying that says: "

The sky and the water are the same color, and boats and ships are coming and going. The only guide is the compass. Watching day and night carefully, without missing a beat, is the difference between life and death

" It means "In the vast and boundless sea, the skyline and the waterside are connected together. The compass is the direction of the ships and small boats in the sea. Pay careful attention to the direction of the compass day and night, and do not dare to deviate at all, because it is related to life and death." This is also related to "Tianshui", but the two "Tianshui" have completely different meanings. One refers to the city and the other refers to "the connection between sky and water". So it depends on which aspect you look at the word "Tianshui". Know which invention you are looking for