When does Gengri mean?

Draw a day with dry branches, and there will be a seventh day when the word "Geng" is dry. The summer solstice is in the middle of the night, which means that autumn begins on the third Geng solstice after long summer.

In ancient China, time was recorded by combining heavenly stems and earthly branches. The number of heavenly stems is 10, which is A, B, C, D, E, Xin, Ren and Gui (guǐ), and the number of earthly branches is 12, which is Zi, Ugly, Yin, Mao, Chen, Si, Wu, Wei and Shen. Heavenly stems and earthly branches, Jia Zi, Yi Chou, Bing Yin, Ding Mao, etc. And cross it for sixty times, so it is called sixty flowers.

Extended data:

midnight

"Three Geng" is to meet three "Geng" characters, and the fourth Geng Day will be the first time. Because the number of heavenly stems is 10, there is a Geng Day every 10 day, such as Geng Zi Day, Geng Yin Day and Chen Geng Day. 365 days a year (366 days in leap year) is not an integer multiple of 10. One day this year is Geng Day, and next year is not necessarily Geng Day. Due to the uncertainty of Geng day, the date of accommodation is different every year.

Sanford

Three volts are divided into: initial volt, intermediate volt and final volt. The third Geng Day after long summer is the first day of first lodging, the fourth Geng Day is the first day of middle lodging, and the first Geng Day after beginning of autumn is the first day of last lodging. The first day and the last day are 10, and the days in between are not fixed. There are four Geng days between the summer solstice and beginning of autumn, with 10 in the middle and five Geng days with 20 days in the middle.

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