How did ancient people measure the total area of China?

In ancient China, the area was estimated, and no one really knew how big it was at that time.

Trouble, thanks!

According to historical records, as early as more than 1,000 years ago, maps were born in China. Hanshu. There are "Suburbs and Heroes".

Yu collects the gold of Jiumu, casts Jiuding, like Kyushu". There is "Zuo Biography": "Cherish the virtue of the summer side, distant pictures, tribute gold and nine herds, cast tripod statues, and prepare for all kinds of things, so that the people know the traitor."

It means that in the heyday of the Xia Dynasty, people from afar drew pictures of landforms, features and beasts, and the governor of Kyushu gave the map and some metals as gifts to Xia Yu, and Yu accepted the "gold of nine herds" to cast the tripod, and cast the paintings painted by people from afar on the tripod, so that the people could distinguish various things from these pictures. The phrase "prepared for all things" in the text clearly indicates that it was a diagram for shepherds and travelers. Unfortunately, when the original logistics was transmitted to the Spring and Autumn Period and the Warring States Period more than 2,000 years ago, it was destroyed due to the war and was lost.

According to the Song Dynasty thinker Zhu Xi, the later "Classic of Mountains and Seas" evolved from the Jiuding image of the Xia Dynasty, and it was also a primitive map. On the "Five Tibets and Three Classics" of the "Classic of Mountains and Seas", mountains, water, animals, plants, minerals, etc. are drawn, and the directions in the Tao are noted, which is a more standardized map form. From this, it can be said that China already had primitive maps in the Xia Dynasty.

In 1986, the map unearthed from the Qin tomb in Fangmatan in Tianshui, Gansu Province, China, is the earliest physical map found in China so far. A total of seven maps have been unearthed at Fangmatan. They are painted on four wooden boards of equal size.

According to the argument of relevant experts, it was drawn in the late Warring States period around 300 B.C., which is more than 1,300 years earlier than the earliest hand-me-down map preserved in China by actual measurement - "Huayi Map" and "Yu Trace Map" in Xi'an Stele Forest, and about 300 years earlier than the Western Han Dynasty map unearthed in Mawangdui, Changsha, Hunan Province in 1973. The map includes the Weishui basin northwest of Boyang Town, Tianshui, Gansu Province, and part of the water system around Fangmatan. There are 82 annotations on the map about place names, rivers, mountains and forest resources.

What is striking is that today's Weishui tributaries, as well as many canyons in the area, can be found on the map, which corresponds to the record in the book "Notes on the Book of Water". The distribution of plants and the natural environment of the various forest trees indicated in the map, such as thistle, cypress, phoebe and pine, are basically the same as those in today's Weishui area. Experts believe that the excavation of the map provides physical evidence for the development of cartography literature in China's pre-Qin period.

The Taishi Prison is a department that specializes in drawing maps and measuring areas! But in ancient times, it was impossible to be so accurate that it was based on estimates!

According to history, there was no approximate map of China's area until the Kangxi reign of the Qing Dynasty. Until then, the boundaries had been determined by approximate boundaries and boundary markers.

Originally, it was the ruler who sent n people to form teams to explore the area and draw a map. Later generations can refer to the literature and drawings left by their predecessors, and each dynasty and generation is constantly contributing to measurement and correction. This is a territorial issue, which every ruler does not ignore.

"Diameter one week and three times" (Han Zhao Shuang's "Notes on the Calculation of the Zhou Dynasty") or "diameter one circumference three" is the basic method of converting the circumference and diameter of the ancient Chinese. This is expressed by the formula, which is c=3xd. This method was still in use during the Kangxi era.

The technique says: The diameter is multiplied by itself, three, four and one", which is the method of calculating the area of the circle expressed in the ancient Chinese arithmetic book. Meaning:

Arithmetic: The area of a circle is multiplied by the diameter of the circle (i.e., the square of the diameter), multiplied by three, and finally divided by four. "In terms of the formula, it is s=3*d 4;

"Step", as an ancient unit of length, the number of steps in the past dynasties is different. According to the relationship between the ancient Chinese "step ruler method": 1 step 6 feet, 1 mile 180 zhang, 1800 feet 300 steps.