All ancient abbreviations.

In ancient times, a day and night was divided into twelve hours, namely:

Zi, Ugly, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu, Hai. Every hour is equivalent to two hours in modern times.

The ancients named each time according to the time of animals in the zodiac. 23 ~ 1 point, 1 ~ 3 points, 3 ~ 5 points, 5 ~ 7 points, 7 ~ 9 points, 9 ~ 1 1 point, at noon,1~ 6544.

Extended data:

Background at that time:

The ancient working people divided a day and night into twelve periods, and each period was called an hour. Twelve o'clock can refer to either a day or any time. Twelve o'clock was created by the ancient working people in China according to the natural laws of the sun, the changes of the sky and the daily production activities and living habits.

This is the twelve-hour system used in the Western Zhou Dynasty. In the Han Dynasty, it was named Midnight, Crow, Pingdan, Sunrise, Food Time, Horn, Japan-China, Sundial, Sunset, Dusk and Man's Decision. It is also expressed by the twelve earthly branches, and it is the child time from 23: 00 to 1 at midnight, the ugly time from 1 to 3: 00, and the Yin Shi time from 3: 00 to 5: 00, which are recursive in turn.

Twelve o'clock consists of twelve specific time nouns. People can find the source of these words from the ancient books of China in the pre-Qin period. Before the Han Dynasty, these appellations were different. Until the early Han Dynasty, China implemented the taichu calendar Law. "Twelve o'clock a day, the main branch is the subject."

The twelve o'clock calendar is unique and has a long history. It is an outstanding contribution of the Chinese nation to the astronomical calendar of mankind and one of the splendid treasures of Chinese culture.

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