In the early days, the centennial system was adopted, that is, day and night were divided into a balanced centenary, starting from sunrise and counting until the next sunrise. A day has 12 hours, and an hour is 8.3 minutes. A 24-hour day and night is 100 minutes, which is equivalent to 1440 minutes now, and each moment is equivalent to 14.4 minutes now.
In the Han Dynasty, it was changed to 120, and in the Southern Dynasty, it was changed to 96, 108. After many twists and turns, it was not until the introduction of European astronomical knowledge in the late Ming Dynasty that the reform of 96 engraving books was put forward and made it a formal system in the early Qing Dynasty. An hour is eight-quarters of an hour. One hour is two hours, and each moment is equivalent to 15 minutes now.
Extended data:
The origin of the word "hour":
In ancient China, the method of "dripping water from a copper pot" was used to measure time, and one day and night were divided into twelve hours, namely, Zi, Ugly, Yin, Mao, Chen, Si, Noon, Wei, Shen, You, Xu and Hai, which correspond to the twenty-four hours today. From eleven to midnight, it's ugly from one to three, Yin Shi from three to five, and so on.
One hour in ancient times is equivalent to two hours today. So when clocks and watches were first introduced into China, some people called an hour "Da Shi" and an hour in the new time "Shi". Later, with the popularity of clocks and watches, the word "big hour" disappeared, but "hour" has been used to this day.
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