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[Diagram of the Life, Death, Directness, and Reversal of the Five Elements]
The verse states:
Wood, Fire, Earth, Metal, and Water—the Five Elements—cycle endlessly, mutually generating each other.
Water, Fire, Metal, Wood, and Earth—the Five Thieves (referring to the relationships of mutual restriction)—cycle endlessly, mutually restricting each other.

[Diagram of the Attribution of Heavenly Stems and Earthly Branches to the Five Elements]
The verse states:
Jia and Yi (Heavenly Stems) along with Yin and Mao (Earthly Branches) belong to Wood, stored in the East;
Bing and Ding belong to Fire, located in the South;
Geng and Xin belong to Metal, attributed to the West;
Ren and Gui belong to Water, in the North;
Wu and Ji belong to Earth, flourishing during the four seasons, positioned in the Center.

[Diagram of the Twenty-Four Solar Terms]
Five days constitute one "Hou" (pentad), and three Hou make one "Qi" (term). Whether it is a large month, small month, or intercalary month, calculations are based on the calendar's solar term intersections. The cold, heat, warmth, and coolness of the four seasons peak in the last month of each season, yet differ from the central position by more than thirty days.
Lichun (Start of Spring), Yushui (Rain Water), Jingzhe (Awakening of Insects) are the solar terms of spring; Chunfen (Spring Equinox), Qingming (Clear and Bright), Guyu (Grain Rain) follow.
Lixia (Start of Summer), Xiaoman (Grain Buds), Mangzhong (Grain in Ear) are the solar terms of summer; Xiazhi (Summer Solstice), Xiaoshu (Minor Heat), Dashu (Major Heat) succeed them.
Liqiu (Start of Autumn), Chushu (Limit of Heat), Bailu (White Dew) are the solar terms of autumn; Qiufen (Autumn Equinox), Hanlu (Cold Dew), Shuangjiang (Frost Descent) follow.
Lidong (Start of Winter), Xiaoxue (Minor Snow), Daxue (Major Snow) are the solar terms of winter; Dongzhi (Winter Solstice), Xiaohan (Minor Cold), Dahán (Major Cold) are deduced.

A day consists of daytime and nighttime totaling twelve Shi (two-hour periods), evenly distributed within a day. Therefore, the wise established copper water clocks where dripping water lifts an arrow; the arrow is divided into one hundred Ke (quarter-hours) for measurement. Regardless of the brightness or darkness of the sun and moon, this measure cannot be escaped. Thus, there are one hundred Ke intervals in a day. The Six Qi govern a year, so each Qi governs sixty days and eighty-seven and a half Ke. From this, we know that the timing of Qi transitions varies. Hence, this diagram is established to clarify this.
Due to the difference in day length between winter and summer, day and night shift relative to each other, and the times of sunrise and sunset vary. However, they ultimately total one hundred Ke, while the Ke of Qi transition remain fixed. In the Jiazi year, the First Qi begins at the first Ke of the water leak (early Yin hour) and ends at eighty-seven and a half Ke (mid-Zi hour). The Second Qi begins again at eighty-seven and six-tenths Ke and ends at seventy-five Ke (four Ke past mid-Xu hour). The Third Qi begins again at seventy-six Ke and ends at twenty-six and a half Ke (mid-You hour). The Fourth Qi begins again at sixty-two and six-tenths Ke and ends at fifty Ke (four Ke past mid-Wei hour). The Fifth Qi begins again at fifty-one Ke and ends at thirty-seven and a half Ke (mid-Wu hour). The Sixth Qi begins again at thirty-seven and six-tenths Ke and ends at twenty-five Ke (four Ke past mid-Chen hour). This is called the annual cycle of the celestial sphere, with remaining Ke entering the initial Ke of the Yichou year. Turning thus to the Wuchen year, the First Qi begins again at the first Ke of the water leak; this constitutes a small cycle of four years. Therefore, the Qi converges in the Shen, Zi, and Chen years due to this. For Si, You, and Chou years, the First Qi all begins at twenty-six Ke. For Yin, Wu, and Xu years, the First Qi all begins at fifty-one Ke. For Hai, Mao, and Wei years, the First Qi all begins at seventy-six Ke. Since the Qi all begin at the same Ke, they are called "San He" (Three Harmonies), and the meaning derives from this. Taking fifteen small cycles as one great cycle results in sixty years.