...Chou and Wei clash Ox and Goat; Northeast and Southwest.

Square Water: Chen, Xu, Chou, and Wei belong to the Central Earth

original: "方水 辰戌丑未屬中央土". The phrase "Square Water" likely refers to the layout of a specific mnemonic diagram. The text confirms that the four "intercalary" branches—Chen (Dragon), Xu (Dog), Chou (Ox), and Wei (Goat)—are associated with the Earth element and the center.

◯ Formula for Determining the Twelve Hours

In traditional China, a day was divided into twelve two-hour periods, each named after an Earthly Branch. This mnemonic helps a person identify the time by observing natural cues like animal behavior or the sun's position.

Midnight is the hour of Zi 11 PM – 1 AM,
Cock-crow is the hour of Chou 1 AM – 3 AM,
Daybreak is the hour of Yin 3 AM – 5 AM,
Sunrise is the hour of Mao 5 AM – 7 AM,
Meal-time is the hour of Chen 7 AM – 9 AM,
Near-noon is the hour of Si 9 AM – 11 AM,
Noon is the hour of Wu 11 AM – 1 PM,
Sun-slanting is the hour of Wei 1 PM – 3 PM,
Late afternoon is the hour of Shen 3 PM – 5 PM,
Sunset is the hour of You 5 PM – 7 PM,
Dusk is the hour of Xu 7 PM – 9 PM,
Deep sleep is the hour of Hai 9 PM – 11 PM.

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◯ Formula for Fixing the Hour of the Tiger

The Yin hour (Tiger, 3–5 AM) was the traditional start of the working day. Because the length of the night changes with the seasons, the "watches" (geng) and "points" (dian) used to measure the Yin hour also shift throughout the year.

In the first and ninth months, it begins when the fifth watch's second point is reached.
In the second and eighth months, it ends at the fifth watch's fourth point.
In the third and seventh months, the level light of dawn marks the Yin hour.
In the fourth and sixth months, the Yin hour is no different from sunrise.
In the fifth month, the sun is already thirty feet high original: "三丈", a traditional measurement of height in the sky.
In the tenth and twelfth months, it is at the fourth watch, second point.
In mid-winter the eleventh month, it reaches all the way to the start of the fourth watch.
This is the timing of the Yin hour that you must remember.

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◯ Method for Determining Sunrise and Sunset

This section provides a guide for where the sun rises and sets according to the compass directions (using the Eight Trigrams and Ten Stems) throughout the year.

In the first and ninth months, it rises at Yi East-Northeast and sets in the Geng direction West-Southwest.
In the second and eighth months, it rises at the Rabbit East and enters the Rooster's field West.
In the third and seventh months, it rises between Kui and Jia Northeast/East and enters the Xin region West-Northwest.
In the fourth and sixth months, it rises at Yin Northeast and hides in the Dog direction Northwest.
In the fifth month, it is born at Gen Northeast and returns to Qian Northwest.
In mid-winter, it rises at Xun Southeast and enters the Kun direction Southwest.