How did the ancients know the dates and solar terms?

In ancient China, there were township officials in the village.

There is a secretary in the county, and these two levels of officials are state officials. The subordinates of the township officials are Li Zheng, Chang Bao and Jia Chang.

It is stipulated that ten households are one and ten households are one.

Li Zheng, Chang Bao, Jia Chang. . . Responsible for the daily management of residents and the masses, convey the instructions of the county and the village, and tell the feelings of the masses below.

The anchor in the county is superior to the country and the government, Bo,

The superior of Governor Bo of the state government is the Qintian Supervision Bureau, or Tianjian Supervision Department. Its staffing and tasks are as follows:

This department is dedicated to making calendars. They stipulate that there are four seasons in a year, which are performed alternately, and then distributed at different levels, only to the people, because the calendar comes from the imperial court, also known as the imperial calendar.

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