From 7: 00 to 9: 00, it is smog time. It is said that dragons can fly in the clouds, and only in the fog will they "see the head but not the tail". However, the dragon is a legendary animal, or an "artificial animal" pieced together by people with "parts" of several animals. Not in reality. Only in fog can people have the illusion of dragons. In this way, the dragon will "appear" in the morning fog. When the dragon is associated with Chen Shi, there is the "Chen Long".
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 basic stereotypes are named. 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.
At twelve o'clock, the twelve-point regimen of Huangdi Neijing is integrated into people's daily life through timing tools, reminding people of scientific regimen at any time and letting everyone know how to use Huangdi Neijing to carry out regimen and popularize scientific regimen, which is undoubtedly of revolutionary significance for improving people's physique and improving people's quality of life.
12 hour is equivalent to 24 hours and 2 hours per hour. It is clearly pointed out in the New Tang Calendar that "the ancient calendar divides the day and begins at midnight", and the midpoint of midnight, that is, today's zero hour (24: 00), is the beginning of the day.