Twenty-Four Solar Terms: Frost Descent

霜降，候雁南向，豺祭獸，霜大下，草未死。候雁南向，陽炁盡之候也。豺將食獸，必先祭也。草禾或為草木。晷長九尺一寸六分。太陽雲出，上如羊，下如磻石。霜降於兊直六三，六三兊爻為羊，又上直礪石之星，故上如羊下如磻石。○案：《初學記》作太陰雲出。

On the day of Frost's Descent, the geese wait for the season and fly south, the jackals arrange the game they have caught and perform a sacrifice, heavy frost falls, but the grass has not yet withered completely. Zheng Xuan explains: the southward flight of the geese is a sign of the waning yang energy. The jackals, before eating the game, must first arrange it and perform a sacrifice. Some versions of the text read 'grass and trees' instead of 'grass and grain'. The shadow measured by the gnomon is nine feet one inch and six parts. The clouds of the sun rise, with the upper part resembling a sheep and the lower part resembling a grinding stone. Zheng Xuan explains: Frost's Descent falls on the sixth line of the third position in the Dui hexagram. The sixth line is the Dui line and represents a sheep, and the upper position corresponds to the star of the grinding stone, so the upper part is like a sheep and the lower part is like a grinding stone. The editors note: The "Initial Learning" records it as "the cloud of Taiyin rises".

當至不至，萬物大耗，來年多大風，人足蹶陰脈虛，多病腰痛。霜降炁不至，則陽炁不伏，當死更生，故令物虛耗。六又互體巽，則暴發，來年即為大風也；又撓屈萬物，故令人患其腰痛也。未當至而至，人足蹶陰脈盛，多病喉風腫。陰炁早至而脅陽也，又互體離，離巽火得風腫。○案：《後漢書》注作多病胃脅支滿。應在榖雨，災期在趙。

At the time of the frost descent, if the cold weather does not arrive as expected, all things will suffer great losses, and the following year will have much wind, with people suffering from weakness in the foot's jueyin meridian and frequent lower back pain. Zheng Xuan explains: if the frost descent does not arrive, yang energy cannot retreat and conceal itself, and things that should wither will instead revive, causing great depletion of all things. The sixth line in the third position also has the mutual trigram of Xun, which will lead to sudden outbreaks, resulting in strong winds the following year. Wind damages and bends all things, hence causing lower back pain. If the frost descent arrives prematurely before its time, the foot's jueyin meridian will become excessive, leading to frequent throat swelling. Zheng Xuan explains: if the yin energy arrives too early and forces yang energy, and since there is also the trigram of Li, the fire of Li meeting the wind of Xun will cause swelling. The editor notes: the annotation in the "Later Han Book" states "many suffer from stomach and side fullness." The time of occurrence is around the time of Grain Rain, and the affected region is Zhao.

立冬，不周風至，始冰，薺麥生，賓爵入水為蛤。立冬應用事，陽炁生異，故不周風至。周達萬物之不及時者，時草死盡，惟薺麥生耳。賓爵入水為蛤，亦物應時之變候。晷長丈一寸二分。陰雲出接。立冬於兊直九四，九四辰在午，火性炎上，故接。○案：《太平御覽》引作「立冬不周風至，修宮室，完邉城，八風以時則陰陽正，治道成，萬物得以育生」，與此文異。

On the day of the Beginning of Winter, the wind from the northwest, the Wind of Not-Spreading, comes, and the water begins to freeze. The plant called ji and the grain called mai start to sprout, and the bird called bin qie enters the water and turns into a clam. Zheng Xuan explains: On the day of the Beginning of Winter, the yang energy begins to produce changes, so the Wind of Not-Spreading arrives. This wind reaches everywhere and benefits those things that have not yet caught up with the season. At this time, all grasses have withered, but ji and mai are still growing. The transformation of the bin qie bird into a clam is also a sign of how things change in accordance with the season. The shadow measured by the gnomon is one zhang, one cun, and two fen long. Dark clouds rise and connect with each other. Zheng Xuan explains: The Beginning of Winter is in the Dui trigram at the Nine in the Fourth line. The Nine in the Fourth line is at the position of Wu, which is the position of fire, which rises upward, so the clouds connect. The editor notes: The "Taiping Yulian" quotes it as "On the day of the Beginning of Winter, the Wind of Not-Spreading comes, and people repair their palaces and complete the borders of their cities. The eight winds come at the proper time, and yin and yang are in harmony, the way of governance is established, and all things are able to grow and be born," which is different from the text of this book.

當至不至，地炁不藏，立夏反寒，早旱晚水，萬物不成，人手少陽脈虛，多病溫心煩。未當至而至，人手少陽脈盛，多病臂掌痛。陰脈在內，故炁早至為病，令人掌及臂痛也。應在立夏，災期在魏。

At the time of the beginning of winter, if the weather does not arrive as expected, the earth's energy cannot be stored. Instead, it becomes cold at the beginning of summer. There is drought in the early period and flooding in the later period, leading to the failure of crops to mature. People suffer from weakness in the hand yang meridian, and are prone to warm diseases and irritability. If the weather arrives prematurely before its time, the hand yang meridian becomes excessive, leading to pain in the arms and palms. Zheng Xuan explains: the yin meridian flows internally, so if the energy arrives too early, it causes illness, resulting in pain in the palms and arms. The expected time is at the beginning of summer, and the area affected by disaster is in the state of Wei.

小雪，陰寒，熊羆入穴，雉入水為蜃。雉入水亦為蜃蛤。晷長丈一尺八分。陰雲出而黑。小雪於兊在九五，九五兊爻得坎炁故黒。當至不至，來年五榖傷，蠶麥不為，人心主脈虛，多病肘腋痛。未當至而至，人心主脈盛，人多病腹耳痛。九五坎爻故耳病也，辰在申炁得故腹痛。○案：此注疑有脫誤。應在小滿，災期在魯。

On the day of Xiaoxue, the weather is gloomy and cold, with bears and badgers retreating into their dens, and wild pheasants entering the water to transform into clams. Zheng Xuan explains: wild pheasants entering the water become clams. The shadow measured by the gnomon is one zhang, one chi, eight fen long. Dark clouds rise and appear black. Zheng Xuan explains: Xiaoxue corresponds to the Dui trigram at the Nine in the Fifth line. The Nine in the Fifth is the Dui line but receives the energy of Kan, hence the black color. If the Xiaoxue phenomenon occurs when it should, then the next year's grain will be damaged, silkworms and wheat will not mature, and the heart's main pulse will be weak, leading to frequent pain in the elbows and armpits. If it arrives prematurely before it should, the heart's main pulse will be excessive, causing frequent abdominal and ear pain. Zheng Xuan explains: the Nine in the Fifth is the Kan line, hence ear diseases; the Chen position is in Shen and receives its energy, hence abdominal pain. The editor notes: this annotation may have omissions or errors. The expected time should be at Xiaoman, and the area affected by disaster should be in Lu.

大雪，魚負冰，雨雪。負冰，上近冰也。雨雪者，明不復雨水。晷長丈二尺四分。長雲出黑如介。大雪於兊直上六，上六辰在已，得巽炁為長，始分或如介未聞。○案：古書作陰雲出而分。

On the day of a heavy snowfall, fish swim near the ice layer beneath the surface, and snow falls from the sky. Zheng Xuan explains: the term "negative ice" refers to fish rising to the surface and coming close to the ice. The mention of "rain and snow" indicates that rain will no longer fall afterwards. The shadow measured by the gnomon is one zhang, two chi, four cun. Long clouds rise, dark in color like armor. Zheng Xuan explains: heavy snow occurs at the upper sixth line of the Dui trigram. The upper sixth position corresponds to the hour of巳, receiving the energy of Xun, hence the long shape of the clouds. As for the saying "beginning to divide" or "like armor," there has not been a clear explanation yet. The editor notes: the ancient book by Sun氏 states "dark clouds emerge and divide."

當至不至，溫炁洩，夏蝗生，大水，人手心主脈虛，多病少炁五疸水腫。未當至而至，人手心主脈盛，多病癰疽腫痛。盛陽之炁早至結，則為癰疽。冬萬物孚甲，炁早至故多疽而痛。應在芒種，災期在衛。

The time for heavy snow has arrived but has not come, causing warm air to escape externally. In summer, locust plagues occur, and great floods happen. The pulse of the palm of the hand becomes weak, leading to frequent shortness of breath, five types of jaundice, and edema. If the heavy snow arrives prematurely before its due time, the pulse of the palm of the hand becomes excessive, leading to frequent abscesses and swellings. Zheng Xuan explains: excessive yang energy arriving too early and stagnating leads to abscesses. In winter, all things are covered with their outer layers, and excessive yang energy arriving too early causes frequent sores and pain. The time of occurrence is at Mangzhong, and the affected region is Wei.

聖人仰取象於天，俯取法於地，以知陰陽精所應。精，晷及雲炁也。應者，應人君政之進退。故日者，眾陽之精也，天所以照四方，因以立定。二十四炁始於冬至，終於大雪，周天三百六十五日分之。

The sage looked up to observe the patterns of heaven and looked down to study the principles of earth, in order to understand the subtle interactions between yin and yang. Zheng Xuan explained that "jing" refers to the sun's shadow and clouds, and "ying" means the response to the ruler's policies and decrees. The sun is the essence of all yang, used by heaven to illuminate all directions, thus establishing the measures and regulations. The twenty-four solar terms begin with the winter solstice and end with major snow, distributing the 365 and one fourth days of the celestial cycle among them.

一陰一陽分之，各得八十二日有竒；分為普，得九十一日有竒。四正分而成八節，節四十五日二十一分。八節各三分，各得十五日七分，而為一炁也。分滿三十二為一日。令備，或為復。言陰陽四時八節二十四炁各如其分之日數，令備為一歲。備，足也。復備同義，說者以為疑字耳，言備或為復。人自以為法度焉。二十四炁其復合於晷應，其法皆先復之二日左同右。

According to the division of yin and yang, each gets eighty-two days and some extra; according to the division of the four seasons, each gets ninety-one days and some extra. The four cardinal trigrams are divided into eight solar terms, each solar term being forty-five days and twenty-one parts; each solar term is further divided into three parts, each part being fifteen days and seven parts, thus forming a solar term. When the parts amount to thirty-two, it counts as one day. Zheng Xuan explained: "To make complete." Some versions read "To make return." This means that yin and yang, the four seasons, the eight solar terms, and the twenty-four solar terms each follow their respective number of days, to make a complete year. "Complete" means sufficient. "Return" and "complete" have the same meaning, and commentators think that "return" might be a mistaken character, hence it is said that "complete" or "return" can be used. People use these as their standards. The verification of the twenty-four solar terms with the shadow length is recombined, and the method is to start two days earlier, with the same amount on both sides.