This technique is based on the traditional Chinese time measurement system and the current version of the "traditional Chinese calendar" which is also used in numerology and Feng Shui arrangements.

In this time measurement system years, months, days, and watches (2-hour periods) are marked by two ordinals — one of the 10 Heavenly Stems (representing phases of the descending Heavenly energy cycle) and one of the 12 Earthly Branch (representing phases of the receiving Earthly energy cycle). In this text we will use a simplified notation “sNbN”, whereas sN is the stem number,  bN is the branch number.

As many things in China, the characters of these two cycles may be attributed to Yin or Yang principle:

Combinations of the signs from these two cycles used sequentially form a new sexagesimal cycle used in Chinese calendar. Thus, the 1st year of the 60-year cycle becomes jia-zi, the 2nd year is yi-chou, the 3rd year is bing-yin, etc. When we reach the end of a component, we start from the beginning: The 10th year is gui-you, the 11th year is jia-xu (restarting the Celestial Stem), the 12th year is yi-hai, and the 13th year is bing-zi (restarting the Terrestrial Branch). Finally, the 60th year becomes gui-hai.

Combinations of the signs from these two cycles used sequentially form a new sexagesimal cycle used in Chinese calendar. Thus, the 1st year of the 60-year cycle becomes jia-zi, the 2nd year is yi-chou, the 3rd year is bing-yin, etc. When we reach the end of a component, we start from the beginning: The 10th year is gui-you, the 11th year is jia-xu (restarting the Celestial Stem), the 12th year is yi-hai, and the 13th year is bing-zi (restarting the Terrestrial Branch). Finally, the 60th year becomes gui-hai. The cyclic naming is applied to years, months, days and day watches. There are more detailed cycles, but for medical purposes we use these four.

Approximately since II century BC the signs of the first group (Denary cycle) were named "Celestial Stems", the signs of the second group (Duodenary cycle) - "Terrestial Branches".

It is customary to number the 60-year cycles since 2637 BC, when the calendar was supposedly invented by the Emperor Huangdi. In that year the first 60-year cycle started.

The twelwe 'watches' of the day are marked by "Terrestial Branches". The arrows show tendencies of the Yin-Yang ratio during the 24 hours.

In the traditional Chinese medicine the signs correlate with the Ba Gua and Wu Xing systems, mark date and time, substances and parts of the human body, the Qi channels and movements of the energy and are widely used for description of general algorithms

The twelwe watches of the day mark periods of rise and declining of Qi in the twelve main channels of the human body.

*** In the traditional Chinese time measuring system the 24 hours are divided into 12 watches in a more complicated way, and the data shown is absolutely valid for the periods close to the vernal and autumnal equinox. In other times of the year watches' length is not equal: in winter night watches are longer and day watches - shorter, and vice versa in the summer. The sunrise is always happen in the middle of the MAO watch, sunset - in the middle of the YOU, noon falls on the middle of the WU, midnight - on the middle of the ZI.

Correlation of the parts of the human body with the Celestial Stems

*** However, the date/time according to the Chinese calendar is accurate for China only, and correction is needed for other parts of the world!