During the Jin Dynasty, Liu Zhiyun, the Shizhong, said, "Zhuanxu created the Hunyi, and the Yellow Emperor invented the Gaitian concept." However, both of these astronomical instruments are now ancient relics. Although they were said to have remarkable abilities as described in legends, their practical uses have been lost.
In the past, the enlightened rulers who led the nation during times of peace and prosperity made circular Gaitian diagrams, with constellations drawn on them. The North Star occupied the center of the circle, used to observe celestial phenomena. They divided the circle into 365 and one-quarter degrees to calculate the number of days in a year. The sun moves along the ecliptic, rotating from west to east, so they drew a circle to represent the sun's orbit. To clearly show the positions of the four seasons, they used different colors: blue for spring, red for summer, white for autumn, and black for winter. The last eighteen days of each season were denoted in yellow.
Although the Gaitian diagrams were well-drawn and looking up at the sky could show the positions of the stars, it was still not possible to accurately determine the length of day and night. Therefore, the Hunyi was created to replicate the movements of celestial bodies. Now, since the Kaihuang period, the realm has been brought together, and the Lingtai continued to utilize the iron Hun Tianyi from the Northern Wei period to track the changes in the seven celestial bodies (Sun, Moon, and five planets), arrange the positions of constellations according to the Gaitian diagrams, delineate the ecliptic and equator, and indicate the degrees of the twenty-eight lunar mansions. However, no one has made any improvements to the Hun Xiang since.
In the fourth year of the Renshou era, Liu Zhuo, a man from Hejian, presented the "Huangji Calendar" to the Crown Prince. The portion discussing the Gaitian concept read as follows:
Speaking of the celestial phenomena up above, people have been trying to understand it since ancient times, using instruments to measure it. Emperors also attached great importance to this topic. Back in the Han Dynasty under Emperor Wu, he tasked Luò Xiàhóng and Xiānyú Wàngrén with studying and creating the calendar. Later, Zhāng Héng picked up the research using a similar method to Luò Xiàhóng's. Although the instruments made by Luò Xiàhóng are no longer available, Zhāng Héng created one. In the Wu Kingdom, Lù Jì and Wáng Fān also worked on this matter, where Lù Jì took a slightly different approach and Wáng Fān's work was similar to Zhāng Héng's. During the Song Dynasty, there were Qián Lèzhī, and the Wèi Dynasty saw figures like Chāo Chóng, who also used copper and iron to create instruments. Though there were some size differences, the design principles were quite similar to Wáng Fān's. Look at Cài Yōng's "Yuè Lìng Zhāng Jù" and Zhèng Xuán's "Kǎo Líng Yào"; they both used Zhāng Héng's method, which still hasn’t changed today.
Although I’m just a small figure, I’ve thought about these things, looking into their calculation methods and discovering many inconsistencies. Some are off by thousands of miles, while others are off by a hair's breadth. If the celestial model is incorrect, then nothing else can be verified. Let alone the constant distances between the equator and the ecliptic, and the moon's movement, which are all tied to weather changes. If even the smallest detail is calculated incorrectly, then using incorrect data repeatedly will only lead to bigger errors, making it impossible to make sense of. This is all due to a lack of clear understanding of the principles, resulting in various schools of thought.
Take "Xuān Yè Lùn" for example; it has three interpretations, with four celestial models: flat, xīn, ān, and qióng, leading to confusion. There is only one principle for celestial movement, so how can there be seven different takes on it? Furthermore, using solar shadows to measure the height of the North Pole and then calculating the celestial globe, this celestial globe is like the human body—it's all interconnected, not something different. What’s proven right will be clear, while what’s wrong will come to light. How can we let the right principles get buried while the wrong ideas keep spreading? It's really a shame!
In the past, Cai Yong, while stationed at Shuo Fang, wrote to the court, saying: "With an eight-foot high instrument, one can measure the celestial phenomena in the universe. The ancients possessed this instrument, yet there are no existing texts that document it. I have always wanted to examine the instrument closely and carefully study its calculation methods, then write a book to explain it." At that time, Cai Yong was punished and stationed at the border, and his memorial was not approved. Even if it had been approved, he probably wouldn’t have been able to accomplish it. Cai Yong's talents did not match those of Zhang Heng, and Zhang Heng himself left no thoughts on it! Thus, without a book to accompany the instrument, one cannot understand the principles merely by observing it.
Now, I need to develop a new method to refine the existing armillary sphere. I will use the length of the sun's shadow at the two solstices to determine the altitude of the North Pole and the scale of the clepsydra, and I will also calculate the height of heaven and earth and the laws of the stars' movements. My methods are grounded in sound principles, supported by appropriate proportional coefficients. I aim to resolve the great doubts of contemporary scholars and verify a series of questions from ancient scholars, illuminating these doubts as if parting the clouds to reveal a clear sky. I have already organized these findings into several volumes, and once the data from the shadow measurements is more precise, I will present it to you.
According to the "Zhou Guan," it is recorded that on the day of the summer solstice, the shadow is one foot and five inches long. However, renowned scholars such as Zhang Heng, Zheng Xuan, Wang Fan, and Lu Ji find this claim to be quite inaccurate; they think the shadow differs by one inch for every thousand miles. They argue that if the sun directly shines on the South Dai River (where "Dai Ri" refers to the point of direct sunlight), which is about 15,000 miles away, then the length of the shadow should be the same, and the difference is only due to the height of the heavens. However, upon closer examination, this claim proves to be completely untenable! Saying the shadow differs by one inch for every thousand miles has no basis; it is purely speculation and utterly unreliable. Currently, in Jiaozhou and Aizhou, the summer solstice shadow is completely absent, and the distance to the point of direct sunlight is undoubtedly greater than ten thousand miles, even further south than the South Dai River. Therefore, the assertion that there is a one-inch difference for every thousand miles simply does not hold true.
Mr. Zhuo (pronounced: zhāo) proposed the 'Huntian' theory (or 'Harmonious Sky'), which is based on the principle of 'Dao.' The values of 'Dao' and 'Li' are variable; only by calculating the differences can accurate values be determined. Now is the Year of the Great Sage, a time of peace and prosperity, making it a perfect time to rectify various misconceptions. He suggested finding a water conservancy project expert and an arithmetic specialist to measure distances of several hundred 'li' in the plains of Henan and Beiping, ensuring perfect alignment in the north-south direction. Using a clepsydra for timing and a rope for measuring flat land, they could accurately measure based on the climatic conditions of the time and measure the length of the shadow on the same day. By calculating the ratio of the differences, the precise value of each 'li' could be determined. This way, nothing in the universe could conceal its form, and celestial phenomena would not escape calculation. This would represent a monumental achievement surpassing that of earlier scholars, dispelling doubts in people's minds! He also said not to dismiss a statement just because of who is speaking. Unfortunately, his suggestion was not adopted. It was not until the third year of the Daye era that the court finally ordered various provinces to measure the shadow, but by then, Mr. Zhuo had already passed away, and the matter was left unresolved.
The "Zhou Li" states that by using a soil gnomon to measure the depth of the land and observing the length of the shadow, one can find the central point of a geographical location. This is foundational to astronomy! The book also states: when the sun is in the south, the shadow is short, and the weather is hot; when the sun is in the north, the shadow is long, and the weather is cold; when the sun is in the east, the evening shadows are windy; when the sun is in the west, the morning shadows are often cloudy. When the sun is directly overhead, and the shadow is one foot and five inches long, this place is called "the center of the earth," where heaven and earth meet, where the seasons alternate, where winds and rains converge, and where yin and yang harmonize. Only in this way can all things flourish, ensuring the nation remains stable and prosperous.
"The Book of Rites" also mentions that when establishing a country, one must consider hydrology and topography, and use wood to create a marker for observing the sun's shadow. They used a compass to draw diagrams, recording the length of shadows at sunrise and sunset. During the day, they would use the shadow at noon for calibration, and at night, they would use the North Star for calibration, thus determining the directions of east, west, south, and north. The ancient methods of measuring shadows using a sundial are described briefly in texts, and previous scholars' explanations were not clear enough. Zu Xun provided detailed annotations on these texts and developed a method for locating the geographical center. His method was as follows: first, observe the times of sunrise and sunset, note the times, and divide the time periods. Then, erect a marker on flat ground, referred to as the South Marker. When the sun is at its zenith, erect another marker at the end of the shadow of the South Marker, called the Middle Marker. At night, based on the position of the Middle Marker, observe the North Star, then erect another marker called the North Marker, aligning these three markers in a straight line. All three markers must be calibrated with a level. If the three markers form a straight line, it means that the location is exactly in the middle of the north-south direction. If the three markers are not in a straight line, it means that the location is off-center. If the Middle Marker is to the west, it means that the measurement location is west of the geographical center, indicating that you should look to the east; if the Middle Marker is to the east, it means that the measurement location is to the east of the geographical center and should be searched to the west. The location where the three markers align in a straight line is the geographical center. On the day of the Spring and Autumn Equinox, when the sun rises from the east, erect a marker to the east of the Middle Marker, called the East Marker, aligning the East Marker, the sun, and the Middle Marker in a straight line. As the sun begins to set, erect a marker to the west of the Middle Marker, called the West Marker, aligning the West Marker, the sun, and the Middle Marker in a straight line. If the three markers form a straight line, it means that the location is in the middle of the north-south direction. If the Middle Marker is slightly south, it means that the measurement location is slightly south in the east-west direction; if the Middle Marker is slightly north, it means that the measurement location is slightly north in the east-west direction. By adjusting the position of the north-south direction until all three markers can form a straight line in the east-west direction, that indicates the geographical center, positioned precisely midway in the east-west direction.
Legend has it that Duke Zhou used a gnomon (a device used to measure the angle of sunlight) to measure the sun's shadow in Yangcheng to determine the position of the sun and calculate the calendar. It is recorded in "The Grand Master of Ceremonies" in the Book of Rites: "Using the method of the gnomon, measure the depth of the earth, correct the length of the sun's shadow, to obtain the center of the earth. The sun's shadow measures one zhang three chi five cun on the winter solstice, and one chi five cun on the summer solstice, which is the sign of the convergence of heaven and earth, and the change of the four seasons. A strong kingdom can only be established when all things thrive and find stability." The sun, the essence of yang energy, is the most prominent celestial phenomenon. All things grow because of it, and the changes in seasons are determined by it. Observing the rise and fall of the sun's shadow, calculating the distance between heaven and earth, determining the direction, calculating the time, establishing leap months—there's no more straightforward way to do this.
However, the methods employed in ancient times were quite rudimentary, and their intricacies are difficult to fully understand. Scholars in later generations who studied astronomy had different results in their calculations. Ancient scholars noted: "During the summer solstice, erect an eight-foot high sundial in Yangcheng, and its shadow length is the same as the one measured by the gnomon." However, according to "The Canon of Yao" in the Book of Documents, it says: "The shadow measures one chi five cun on the summer solstice, and one chi three cun on the winter solstice." The "Verification of the Hexagrams in the Book of Changes" states: "On the day of the winter solstice, erect an eight-foot high sundial, observe the length of the shadow at noon, and predict the abundance or scarcity of the coming year. The shadow measures one chi four cun eight fen on the summer solstice, and one zhang three chi on the winter solstice." In the "Zhou Bi Suan Jing," it is written: "In the Chengzhou region, the shadow measures one chi six cun on the summer solstice, and one zhang three chi five cun on the winter solstice." In Liu Xiang's "Biographies of Eminent Women," it is recorded: "The shadow measures one chi five cun eight fen on the summer solstice, and one zhang three chi one cun four fen on the winter solstice, with a difference of two fen during the spring and autumn equinoxes." The "Four-Fold Calendar" of the Later Han Dynasty, the "Jingchu Calendar" of the Wei Kingdom, the "Yuanjia Calendar" of the Song Dynasty, and the calendar of the Ming Dynasty's Zu Chongzhi all agree with the results in "The Canon of Yao" in the Book of Documents. The capitals of the Han Dynasty, the Wei Dynasty, and the Song Dynasty were all different, but the results of the four calculations of the sun's shadow were the same. However, it is likely that the information in those astronomical almanacs is not entirely reliable. The shadow lengths during the spring and autumn equinoxes, as mentioned by Liu Xiang, were calculated using proportional reasoning rather than actual observations.
Look, the length of the sun's shadow can be estimated roughly, but even in the same location, the measurement results may vary slightly; in different regions, the length of the sun's shadow will certainly differ. This is probably because the ancient scholars' measurements were not precise enough, leading to discrepancies in their calculations. Now, I will simplify these complex records and present them here.
During the Liang Dynasty, Zu Cheng created a copper gnomon that was eight feet tall, with a gnomon connected below (the gnomon: an ancient instrument for measuring the sun's shadow). There was a groove on the gnomon to hold water in order to ensure it was level. It was then used to measure the variations in the length of the sun's shadow.
In the tenth year of the Daitong era of the Northern Wei, the Grand Historian Yu Guang used a nine-foot-tall gnomon to measure the sun's shadow in the Jiangzuo region. He measured the summer solstice's shadow to be one foot three inches two tenths long, the winter solstice's shadow to be ten feet three inches seven tenths long, the shadows at the beginning of summer and autumn to be two feet four inches five tenths long, and the shadows on the spring and autumn equinoxes to be five feet three inches nine tenths long. During the Chen Dynasty, the measurement methods of the Liang Dynasty continued to be used. The Emperor Shunwu of the Northern Qi moved the old measuring instruments from Luoyang to Ye City, and they were not recalibrated until the death of Emperor Wenxuan.
It wasn't until the seventh year of the Wuping era of the Northern Zhou that Gan Jingli recommended Liu Xiaosun and Zhang Mengbin to the later ruler. Liu Xiaosun and Zhang Mengbin recreated the gnomon to measure the sun's shadow to validate the accuracy of the solar terms. However, just as they began their work, the dynasty came to an end.
Starting from the Tianhe era of the Northern Zhou, many people began to study the calendar, measuring the sun's shadow at the solstices to test the precision of the calendar. After Emperor Gaozu ascended to the throne of the Sui Dynasty, the court discussed the need to reform the calendar. Zhang Zhouxuan, who was well-versed in astronomical measurements, stated that a lengthening of the sun's shadow was an omen of good fortune. The emperor ordered the relevant departments to carry out research, but there was no conclusion reached.
In the nineteenth year of Kaihuang, Yuan Chong became the Grand Historian. He wanted to complete what Zhang Zhi Xuan had not finished before. He submitted a memorial saying: "After the establishment of the Sui Dynasty, the length of the shadow gradually shortened. In the winter solstice of the first year of Kaihuang, the length of the shadow was 12.7 feet, and it continued to shorten thereafter. By the winter solstice of the seventeenth year of Kaihuang, the length of the shadow was one zhang, two chi, six fen, three minutes long. In the fourth year of Kaihuang, the winter solstice shadow measured in Luoyang was one zhang, two chi, eight fen, eight minutes long. In the second year of Kaihuang, the summer solstice shadow was one chi, four fen, eight minutes long, and it also continued to shorten thereafter. By the summer solstice of the sixteenth year of Kaihuang, the shadow was one chi, four fen, five minutes long. The winter solstice of the eighteenth year of Kaihuang could not be measured because of cloudy weather. The summer solstices of the first, seventeenth, and eighteenth years of Kaihuang were also unable to be measured due to cloudy weather. According to the Zhou Li, the shadow was measured with a gnomon, and the summer solstice shadow was one chi, five fen long. Zheng Xuan said: 'The winter solstice shadow is 13 feet long.' Now, the summer solstice shadow of the sixteenth year of Kaihuang is five minutes shorter than before, and the winter solstice shadow of the seventeenth year is three fen, seven minutes shorter than before. When the sun is nearer to the North Pole, the shadow is short and the day is long; when the sun is far from the North Pole, the shadow is long and the day is short. Now, the sun's path is currently closer to the North Pole. The Yao Dian says: 'The sun is short and the Pleiades are visible, marking the midwinter.' Based on the appearance of the Pleiades at dusk, it can be known that during the time of Yao, it was the middle of winter, and the sun was positioned ten degrees in the constellation of Virgo. According to the calendar calculation, during the winter solstice of the Kaihuang era, the sun was positioned eleven degrees in the constellation of Dipper, similar to that of Emperor Yao, both being relatively close to the North Pole. The Yuan Ming Bao says: 'The sun and moon move in their orbits, and the Xun Ji has its regularity. The Heavenly Emperor is revered, and the Holy King has accomplished his initial achievements.' Jing Fang's "Bie Dui" says: 'In the era of Taiping, the sun follows the upper path; in the era of Shengping, the sun follows the middle path; in the era of Bada, the sun follows the lower path.' Our great Sui Dynasty founding, heaven was moved, the shadows grew shorter, and the days grew longer. This is truly a rare occurrence in history!"
At that time, the deposed commoner Yong, Prince Guang of Jin, had just been established as the crown prince, and Yuan Chong reported this to the emperor, which was quite timely. When the emperor went to court, he said to the officials, "The shortening of the shadow is a divine blessing! Now that the crown prince has just been established, the era should be changed, naming the year based on the shortening shadows." So, the 21st year of Kaihuang was changed to the first year of Renshou. After that, all construction projects and taxes were raised, justified by the shortening of the shadow. The crown prince led the officials to the gate of the palace to congratulate. In fact, the variations in shadow length are perfectly normal, but Yuan Chong and others took it as an auspicious sign, which drew criticism from many.
Wow, these ancient folks really studied shadows closely! Take a look at what's mentioned in these texts: "Kao Lingyao," "Zhou Bi," "Ling Xian," and Zheng Xuan's commentary on "Zhou Guan" all noted that the shadow on the ground varies by one inch for every thousand li. However, in the 19th year of Song Yuanjia (442 AD), the court sent people to Jiaozhou to measure the shadow, and on the summer solstice, the shadow measured three inches and two fen. He Chengtian measured the summer solstice shadow in Yangcheng to be one foot five inches. The distance from Yangcheng to Jiaozhou is roughly ten thousand li, but the shadow difference was one foot eight inches and two fen, which means there's a one-inch difference every six hundred li. During the Liang Datong period (535-546 AD), people measured the shadow of the summer solstice again, using an eight-foot high instrument, and the shadow was approximately one foot, one inch, and seven fen. In the Wei Dynasty, Xindu Fang commented in "Zhou Bi Four Arts" that in the first year of Yongping (68 AD), which was the seventh year of Tianjian in Liang (508 AD), the shadow measured in Luoyang and the one observed by Gongsun Chong with the ministers in the Secretariat on the summer solstice was one foot five inches and eight fen. The distance between Luoyang and Jinling is roughly a thousand kilometers, but the shadow difference was four inches, meaning there's a one-inch difference every two hundred fifty li. Just think about it: the actual distance traveled is definitely longer than the straight-line distance, and considering the ups and downs of mountains and rivers, and winding roads, the error is even greater. Therefore, the saying "one inch difference for every thousand li" might not hold true. Take a look at these measurement results; the differences are quite significant, so we need to study them closely.
Let's talk about how ancient people measured time. The use of water clocks for timekeeping began during the era of the Yellow Emperor, which was a remarkable invention used to distinguish between day and night. Later, a specific official position was established to oversee this matter; the "Keeper of the Water Clock," mentioned in the "Rites of Zhou," was responsible for this. Their method was to divide a day into one hundred segments of time, with daytime and nighttime each occupying half. During the winter solstice, daytime was forty "ke" long, while nighttime was sixty "ke" long; during the summer solstice, daytime was sixty "ke" long, and nighttime was forty "ke" long; during the spring and autumn equinoxes, both day and night lasted fifty "ke." The day began to brighten two and a half "ke" before sunrise, and it became dark two and a half "ke" after sunset, which adds up to five "ke" that were included in the daytime, referred to as "dawn and dusk." The water level in the clock changed with the seasons, and the difference in length between day and night between the winter solstice and the summer solstice was twenty "ke." Each difference of one "ke" was referred to as an "arrow." Starting from the winter solstice, there were a total of forty-one arrows. The daytime was divided into five segments: morning Chao, afternoon Bu, Zhong, evening Xi, and Yu; the nighttime was divided into five segments: Jia, Yi, Bing, Ding, and Wu; and there was also a segment during dawn and dusk called Xing Zhong. Each arrow corresponded to a specific time used to arrange people's work and rest.
After the establishment of the Han Dynasty, Zhang Cang continued the previous system, resulting in many gaps and mistakes. Later, Emperor Wu of Han studied astronomy and calendars in depth, using the water clock to measure celestial movements to address earlier shortcomings, but he still struggled to grasp the underlying principles. Liu Xiang recorded the timekeeping methods used during Emperor Wu's reign in "Hong Fan Zhuan": "Between the winter solstice and the summer solstice, there are approximately one hundred eighty days, with a twenty 'ke' difference between day and night." Generally, after the winter and summer solstices, the day-night difference changed by one "ke" every nine days.
During the reign of Emperor Ai of Han, the timekeeping method was modified to a system of 120 divisions for both day and night, but this system was soon discarded. After Wang Mang usurped the throne, this method was reinstated. In the early period of Emperor Guangwu, the method of adjusting the time by one division every nine days was also adopted, and it was incorporated into the "Jia Ling," referred to as "Changfu Loupin." It was not until the fourteenth year of Emperor He's Yongyuan era that Huo Rong presented a report stating, "The official calendar uses a method of increasing or decreasing one division every nine days, which does not align with actual celestial phenomena. Sometimes the error even reaches two and a half divisions, making it preferable to use the summer calendar's timekeeping method, adjusting the length of day and night based on the sun's movement in the north-south direction." The emperor then ordered the adoption of the summer calendar's timekeeping method.
This method calculates time based on the degrees the sun travels along the ecliptic and its distance from the celestial pole, increasing or decreasing one division for every two degrees and four minutes of arc. A total of forty-eight arrows were utilized for timekeeping, and this system remained in place until the Wei and Jin dynasties.
He Chengtian of the Song Dynasty, by observing the positions of lunar eclipses and the lengths of the sun's shadows, deduced the sun's movement patterns and found that it deviated by six degrees from previous calculations. He also discovered that by measuring the length of the sun's shadow on the winter solstice, the timing of the winter solstice was four days earlier than previously estimated. The earlier timekeeping tools had considerable errors, exceeding half a division, as daytime was longer during the vernal equinox and shorter during the autumnal equinox. This was all a result of an inaccurate understanding of the sun's movement patterns. Consequently, He Chengtian undertook to improve the timekeeping method and established a new system of water clocks, stipulating that during the spring and autumn equinoxes, both day and night would each be measured using fifty-five divisions.
During the early periods of the Qi and Liang dynasties, this system remained unchanged. By the sixth year of the Tianjian era under Emperor Wu of Liang, because the day and night were divided into one hundred kè allocated to twelve shichen, with each shichen containing eight kè and some leftover, it was changed to ninety-six kè, with each shichen containing exactly eight kè. By the tenth year of Datong, it was revised again to one hundred eight kè, a figure derived from the phrase "thirty-six qing for day and night" in the "Shangshu Kaolingyao," multiplied by three. Specifically, during the winter solstice, there were forty-eight kè for the daytime and sixty kè for the nighttime; during the summer solstice, seventy kè for the daytime and thirty-eight kè for the nighttime; during the spring and autumn equinoxes, sixty kè each for daytime and nighttime, with three kè for both early morning and evening. Previously, an official named Zu Chen compiled the *Loukeng*, which calculated the sun's movement speed based on celestial sphere theory, considering the distance and speed of the sun's ecliptic. During the Tianjia period of Emperor Wen of Chen, another official, Zhu Shi, was commissioned to create a water clock, upholding the ancient method of one hundred kè. The Zhou and Qi dynasties adopted the water clock method of the Wei dynasty, and during the grand periods of the Jin, Song, and Liang dynasties, one hundred kè was used to divide day and night.
In the early Sui dynasty, the *Loukeng* created by the Zhou dynasty's Yin Gongzheng and Ma Xian was in use. By the fourteenth year of the Kaihuang era, Sima Yuan Chong from Fuzhou presented a new timekeeping device—the gnomon water clock. This device measured the length of the sun's shadow, evenly divided into twelve shichen, to calibrate the speed of the water flow by observing the shichen and the scale that the shadow pointed to. Since the number of kè for each shichen varied, the scales also varied depending on the time. He calculated time using the arrow kè method, following the patterns of the solstices and equinoxes, as follows:
Winter solstice: sunrise at Chen and sunset at Shen, forty kè for the daytime and sixty kè for the nighttime. Zi, Chou, and Hai each have two kè; Yin and Xu each have six kè; Mao and You each have thirteen kè; Chen and Shen each have fourteen kè; Si and Wei each have ten kè; Wu has eight kè. The above outlines the arrow kè method revised after the fourteenth day.
Spring and autumn equinoxes: sunrise at Mao and sunset at You, fifty kè each for day and night.
At the fourth quarter of the Zi hour, the seventh quarter of the Chou hour and the Hai hour, the ninth quarter of the Yin hour and the Xu hour, the fourteenth quarter of the Mao hour and the You hour, the ninth quarter of the Chen hour and the Shen hour, the seventh quarter of the Si hour and the Wei hour, and the fourth quarter of the Wu hour. These adjustments to the sundial will take effect five days later.
On the day of the summer solstice: the sun rises at the first quarter of the Yin hour and sets at the first quarter of the Xu hour, with sixty quarters during the day and forty quarters at night. At the eighth quarter of the Zi hour, at the tenth quarter of the Chou hour and the Hai hour, at the fourteenth quarter of the Yin hour and the Xu hour, at the thirteenth quarter of the Mao hour and the You hour, at the sixth quarter of the Chen hour and the Shen hour, at the second quarter of the Si hour and the Wei hour, and at the second quarter of the Wu hour. Nineteen days later, adding or subtracting a quarter, the sundial is adjusted again.
Yuan Chong didn't understand the relationship between the Northern Wei celestial sphere, the ecliptic, and the North Star at all. He only relied on his own cleverness to arbitrarily change the previous regulations, and in practice, it was not accurate at all. In the seventeenth year of Kaihuang, Zhang Zhouxuan used the Northern Wei celestial sphere to calculate and found that during the spring and autumn equinox, the sun did not rise and set due east and west, but slightly to the north. This result was similar to what He Chengtian calculated; both of them found that the sun rose at the third quarter of the Mao hour and fifty-five minutes and set at the fourth quarter of the You hour and twenty-five minutes. The daytime time measurement showed fifty quarters and eleven minutes, and the nighttime showed forty-nine quarters and forty minutes, with a difference in time between day and night of one-sixtieth of forty quarters. In the fourth year of Renshou, Liu Chao submitted the "Huangji Calendar," which calculated the speed of the sun's movement and accurately determined the dates of the twenty-four solar terms. On the day of the spring and autumn equinox, it was about eighty-eight days from the winter solstice and about ninety-three days from the summer solstice. On this day, there were fifty quarters each for day and night. Based on the Northern Wei celestial sphere and the ecliptic, he verified that on the night of the winter solstice, it was fifty-nine quarters plus one eighty-sixth of a quarter, and during the day it was forty quarters and fourteen minutes; on the day of the summer solstice, it was fifty-nine quarters and eighty-six minutes during the day, and forty quarters and fourteen minutes at night; between the winter solstice and the summer solstice, the difference in day and night duration was nineteen quarters and one seventy-second of a quarter. The time measurements calculated by Zhang Zhouxuan and Liu Chao were not actually adopted. Notably, their methods and systems were recorded in the calendar and, after being tested over time, were very detailed and accurate.
During the reign of the Daye era, Geng Xun made an ancient water clock and presented it to Emperor Yang of Sui by using a dripping method to fill it with water. The emperor liked it very much and instructed Geng Xun and Yu Wenkai to create a more precise timepiece using the refined technique employed by the Northern Wei Taoist Li Lan during his practices. They were to carry it with them at all times.
He also made a sundial water clock that measured time based on the changes in the sun's shadow, which was set up beneath the drum tower in front of the Qianyang Hall in the Eastern Capital, where the official in charge of timekeeping was located. Geng Xun also made a portable water clock that could be placed on a horse, allowing the emperor to check the time whenever he traveled. Using a sundial to measure the sun's shadow and a water clock to keep time, both of these tools are essential for understanding the laws of heaven and earth and mastering time.
The methods of making sundials and water clocks have changed significantly from ancient times, so I have outlined the differences between them and supplemented earlier records.
The North Star and the Six Hook Chen Stars are all located in the Purple Palace. The North Star, also known as Beichen, with its pivotal star, serves as the axis of the heavens. While the stars in the sky are in constant motion, the sun, moon, and stars alternate in their shining, the North Star remains stationary. It is said, "It stays in its position, and the other stars revolve around it." Jia Kui, Zhang Heng, Cai Yong, Wang Fan, and Lu Ji all believed that the North Star is the pivot of the heavens and is an immovable point. Zuxian used instruments to observe and discovered that at the end of the pivotal star, there was a little over one degree.
Among these five stars of the North Star, the dimness of the middle star indicates the emperor's negligence in handling state affairs; the dimness of the star on the right signifies danger for the crown prince. The Hook Chen Star is the rear palace, the residence of the empress, and the emperor's seat. The four stars to the north are known as the Female Imperial Palace, representing eighty-one concubines. The star at the mouth of the Hook Chen Star is called the Heavenly Emperor, and its spirit is known as the Yaopo Treasure, which governs all deities and contains the map of all gods. The four stars surrounding the North Star are referred to as the Four Assisting Stars, which aid the North Star in issuing decrees.
The nine stars above the Celestial Emperor are called Hua Gai (华盖), resembling an umbrella that covers the Celestial Emperor's throne. Above them, nine stars are aligned in a straight line, called Gang. The five stars below the Hua Gai are known as the Five Emperors' Inner Court, which is the place where the emperor resides, emphasizing orderly governance. If a guest star encroaches upon the throne of the Purple Palace, the ministers will be in danger. The six stars next to the Hua Gai and Gang are called Liu Jia (六甲), which can be used to distinguish between yin and yang and to calculate the solar terms; thus, they are beside the emperor to issue edicts and announce seasonal changes.
The star located east of Polaris is called Zhu Xia Shi, tasked with recording errors. In ancient times, there were left and right court historians, which this symbolizes. The star north of the Zhu Xia Shi is called Nv Shi, a low-ranking female official tasked with relaying messages. Thus, during the Han Dynasty, there were court historians. The nine stars of the Chuan She are above the Hua Gai, near the Milky Way, representing the residence of guests, indicating the entrance of the Hu people into the Central Plains. If a guest star approaches it, caution is warranted against treacherous envoys, also foreshadowing the Hu people plotting rebellion.
The five stars south of the Chuan She in the Milky Way are called Zao Fu, overseeing horses and carriages, also known as Si Ma or Bo Le. If this star vanishes, horses will become exceedingly valuable. The nine stars in the west of the Milky Way resemble a hook, known as Gou Xing; if they extend out, an earthquake will occur. The Tian Yi Xing, located south of the star on the right side of the Purple Palace gate, is the deity of the Celestial Emperor, overseeing warfare and capable of foreseeing both fortune and disaster. The Tai Yi Xing, located very close to the Tian Yi Xing, is also a deity of the Celestial Emperor, overseeing sixteen deities, capable of predicting disasters such as wind and rain, droughts, wars, famines, and plagues in various countries.
The Purple Microcosm consists of a total of fifteen stars, seven in the west and eight in the east, all north of the Big Dipper. The brightest star in the center is called Zi Wei Xing, which is the seat of the Celestial Emperor and the residence of the Son of Heaven, governing the commands of the realm and various institutions. Other stars, such as Chang Yuan Xing, Tian Ying Xing, and Qi Xing, act as the guardians of the Zi Wei Xing, much like the ministers of the Son of Heaven. If a military coup occurs in the palace, the Qi Xing will stand upright, signifying that the Son of Heaven will personally lead his troops into battle.
Under the eastern wall, there are five stars called the Celestial Pillar Stars, which oversee the governance and education of the nation and serve as the place for issuing decrees. On the first and fifteenth day of each month, the court announces decrees at the position of the Celestial Pillar Stars for all officials to know. This is similar to the tradition in the "Book of Rites," where decrees are hung on the first day of the first month. In the southeast direction inside the palace gate, there are five stars called the Chancellor Stars, responsible for collecting various information and providing counsel to the emperor day and night, symbolizing the acceptance of counsel, akin to the ancient dragon totem. To the west of the Chancellor Stars, there are two stars called the Yin De and Yang De Stars, responsible for disaster relief efforts for victims. On the inner left side of the palace gate, there are two stars called the Great Justice Stars, responsible for judging cases. Outside the palace gate, there are six stars called the Heavenly Bed Stars, symbolizing the emperor's sleeping quarters, serving as a resting place. Outside the southwest corner, there are two stars called the Inner Kitchen Stars, responsible for the dietary needs of the harem, overseeing banquets for the empress and crown prince. Outside the northeast corner, there are six stars called the Heavenly Kitchen Stars, responsible for overseeing royal feasts.
The Big Dipper, along with a guiding star to the north of the Northern Wall, is the axis of the seven governing stars, the cornerstone of yin and yang. Therefore, as they traverse the sky, they govern the four cardinal directions, dominate the change of seasons, and balance the energy of the five elements. The first four stars of the Big Dipper are known as Xuán Jī, and the last three stars are called Yù Héng. They also symbolize commands and represent the celestial chariot of the Heavenly Emperor, embodying the meaning of movement and change. The Big Dipper, from the first to the seventh star, is respectively called Tian Shu, Tian Xuán, Tian Ji, Tian Quan, Yu Heng, Kai Yang, and Yao Guang. The first four stars are the Dipper, and the last three stars are the Ladle. In ancient beliefs, Tian Shu represents the heavens, Tian Xuán represents the earth, Tian Ji represents humanity, Tian Quan represents time, Yu Heng represents music, Kai Yang represents law, and Yao Guang represents the stars.
Some say that the first star of the Big Dipper is the Zhengxing, representing virtue and benevolence and symbolizing the emperor; the second star is the Faxiang, representing punishment and justice and symbolizing the empress; the third star is the Lingxing, representing disasters; the fourth star is the Zhi star, representing divine justice and punishing the unjust; the fifth star is the Shaxing, representing the center and aiding in the punishment of criminals across the four directions; the sixth star is the Weixing, which symbolizes the provisions in the heavenly granary; the seventh star is the Buxing, also referred to as the Yingxing, representing the military. Some also say that the Big Dipper represents the seven elements of heaven, earth, fire, water, wood, metal, and earth, as well as the seven vassal states of Qin, Chu, Liang, Wu, Zhao, Yan, and Qi.
It is said that in the sky, the leading star of the Big Dipper, which consists of four stars, symbolizes the nobleman's prison, representing divine justice! The auxiliary star revolves around the Kaiyang star, helping the Big Dipper fulfill its duties. It is in charge of emergencies and righteousness, correcting improper behavior, and is considered a symbol of the prime minister. If the Seven Luminaries (the sun, moon, and five planets) shine brightly, the country will prosper; if they do not shine, the country will suffer. If there are many stars surrounding the Big Dipper, the nation will enjoy peace; if there are few stars within the Big Dipper, the common people will fear their rulers, and there will be many lawsuits in the country. If there are no stars for twenty consecutive days, it signifies great disaster. If the auxiliary star shines but the Big Dipper does not, the officials will be strong and the monarch weak; if the auxiliary star does not shine but the Big Dipper does, the monarch will be strong and the officials weak. The handle of the Big Dipper, which includes the three southern stars and the leading star, all represent the Three Excellencies of State, responsible for promoting education, regulating the Seven Luminaries, harmonizing yin and yang, and managing state affairs.
Wenchang Star, along with the six stars in front of the Great Bear's Kuixing, represents the six celestial treasuries, responsible for gathering and calculating the heavenly principles. The first star is called Shangjiang, the Grand Marshal, in charge of military power; the second star is called Cijiang, akin to the Minister of Personnel, overseeing the left and right; the third star is called Guixiang, similar to the Minister of Rites, in charge of ceremonies and education; the fourth star is known as Silu and Sizhong, similar to the Minister of Justice, responsible for rewarding merits and promotions; the fifth star is called Siming and Sigui, equivalent to the Grand Historian, in charge of eliminating disasters; the sixth star is called Sikou, equivalent to the Ministry of Justice, assisting in managing the judiciary. This first star is located in front of the Great Bear's Kuixing, near the inner steps. If it shines brightly and evenly, it is an auspicious omen from heaven.
To the north of Wenchang Star lies a cluster of six stars known as Neijie, the palace of the Heavenly Emperor. There is also a star called Xiangxing, to the south of the Great Bear. This Xiangxing oversees all officials, responsible for the nation's education, assisting the emperor, stabilizing the country, and handling various affairs. If it shines, it is a sign of good fortune. The Sun Guard Star, to the west of Xiangxing, represents generals and ministers, in charge of vigilance and military defense. If it is abnormal, war will break out. The four stars in the northwest are known as Shixing, representing those subjected to corporal punishment. The Tianlao Star, a cluster of six stars located below the Great Bear's Kuixing, serves as the prison for nobles, responsible for overseeing faults and crimes, curbing tyranny and debauchery.
Ah, Taiwei is the emperor's palace, the seat of the Five Emperors, and also the abode of the Twelve Lords. The stars surrounding it represent the Nine Ministers. It is said that Taiwei resembles a scale, and a scale is mainly used to measure fairness. It also represents the heavenly court, responsible for handling various matters, supervising rewards and punishments, with the stars receiving the heavenly mandate, and the gods assessing the seasons, dealing with various issues, and resolving various difficult problems. The two stars in the south among those stars are called the Gate of Duan. The star on the east is called Left Law Enforcement, similar to the Tingwei (an ancient judicial officer); the star on the west is called Right Law Enforcement, similar to the Yushi Dafu (an ancient inspector). Law enforcement serves to expose wrongdoers and their misdeeds. To the east of Left Law Enforcement lies the Left Yemo, and to the west of Right Law Enforcement is the Right Yemo. The four stars on the east are: the southernmost star is designated as the Upper Minister, the star to its northeast is the Sun Gate; the second star is called the Second Minister, the star to its northeast is the Zhonghua East Gate; the third star is called the Second General, the star to its northeast is the East Taiyin Gate; the fourth star is called the Upper General. These four stars are referred to as the "Four Assistants." The four stars on the west are similar: the southernmost star is designated as the Upper General, the star to its northwest is the West Sun Gate; the second star is called the Second General, the star to its northwest is the Zhonghua West Gate; the third star is called the Second Minister, the star to its northwest is the West Taiyin Gate; the fourth star is called the Upper Minister. They are likewise known as the "Four Assistants." If the stars on the east and west flicker or shake, it signals that the lords are conspiring to rebel. If the positions of the law enforcement stars change, the punishments will become harsher. If the moon and the five stars offend the central palace (the center of Taiwei Palace), punishment will ensue; if the moon and the five stars enter the orbit of Taiwei, this will be an auspicious sign.
The three stars outside the southwest corner are called Mingtang, which is the place where the emperor handles state affairs. The three stars to the west of Mingtang are called Lingtai, which is an observation platform mainly used to observe celestial phenomena, examine auspicious signs, and predict disasters. The star to the northeast of the law enforcement officials is called Ye Zhe, in charge of receiving guests. The three stars to the northeast of Ye Zhe are called San Gong Nei Zuo, which is the venue for court meetings. The three stars north of San Gong are called Jiu Qing Nei Zuo, overseeing various affairs. The five stars to the west of Jiu Qing are called Nei Wu Zhu Hou, who serve the emperor without returning to their fiefs. If the rituals of Bi Yong, the ancient site of the emperor's lectures, are perfected, then the stars of the lords in Tai Wei Palace will shine brightly.
The central star in Tai Wei Palace is known as Huang Di Zuo, which governs the deity of the central axis. If the emperor's actions align with the will of heaven, cease in accordance with the will of the people, and remain impartial, then the five emperor positions in Tai Wei Palace will radiate brightly. If Huang Di Zuo does not shine brightly, the monarch must seek wise advisors for assistance; otherwise, he will lose power. Some also say that if the five emperor positions in Tai Wei Palace appear dim and dark blue-black, it foretells the emperor's impending loss of the country. There are also the four emperor positions, which are four stars flanking Huang Di Zuo. The eastern star represents the deity of Cang Emperor's spiritual might; the southern star symbolizes the deity of Chi Emperor's wrath; the western star is the god of the Bai Emperor's summons; the northern star is the god of the Hei Emperor's light and record.
Speaking of the heavens, the star near the North Star is called "Tai Zi," representing the emperor's heir, and the star next to the Tai Zi is called "Cong Guan," meaning attendants. The star in the northeast direction of the emperor's seat is called "Xing Chen," specifically referring to the emperor's favored minister. Looking at the four stars of "Ping," they are located inside the palace gate, close to the officials responsible for law enforcement. The term "Ping" refers to the shielding of the royal palace. The law enforcement officials are mainly responsible for supervising and impeaching; if the ministers show respect to the emperor, these stars will shine brightly and thrive.
Next are the fifteen stars known as "Lang Wei", located in the northeast direction of the emperor's seat, also referred to as "Yi Wu", which represent the positions of Lang officials. During the Zhou Dynasty, the positions included Yuan Shi, while in the Han Dynasty, they included Guanglu, Zhongsan, Jianyi, Yilang, and San Shu Langzhong; all these official titles fall under the category of Lang officials. Some say this is akin to the modern-day Shangshu. The primary responsibility of Lang officials is to defend and protect. If these stars are bright, it suggests that ministers may pose a threat to the emperor, or, according to some, that external forces may stir up trouble. If these stars are incomplete, it indicates that officials may die in the future, and the emperor's favored ministers could also face execution. If a guest star appears here, it could signal a rebellion among the ministers. Further north, there is a star named "Lang Jiang", which is responsible for inspecting the army and overseeing military affairs. Another star, "Wu Ben", is located to the west and north of Taiwei Yuan, near Xia Tai, which oversees the cavalry officers responsible for guarding the palace.
"Chang Chen" seven stars, shaped like a broom, located north of the emperor's seat, serve as the garrison for the imperial guard, Wubei, symbolizing a powerful army. If these stars shake, it means the emperor will lead the army personally; if the stars shine brightly, it means the army is strong; if the stars are dim, it means the army is weak. "San Tai" six stars, paired together, starting from Wenchang and extending all the way to Zhaoyao and Taiwei. Some refer to this as the heavenly pillar, representing the ranks of the three officials. In the sky, it is called "San Tai," responsible for promoting good governance and issuing decrees. The two stars to the west of Wenchang are known as "Upper Tai," responsible for overseeing destiny and longevity; the two central stars are referred to as "Middle Tai," responsible for the ancestral temple; the two stars in the east are called "Lower Tai," responsible for salary and military, tasked with promoting good governance and preventing evil. Some also say that "San Tai" is the ladder in the sky, which the Taiyi god will walk up and down. There is also a belief that "San Tai" is the platform, with the upper stars representing the emperor and the lower stars representing the empress; the middle stars representing the three officials and lower officials; and the lower stars representing scholars and commoners. This symbolizes the harmony of yin and yang and the orderly functioning of all things. If any of these stars behave unusually, their meanings must be interpreted to forecast good or bad fortune. As long as the ruler and subjects are harmonious, the country can be stable. Finally, the four southern stars are known as "Nei Ping," responsible for law enforcement and judicial matters. The star north of the Middle Tai is called "Da Zun," representing the imperial family; the star south of the Lower Tai is called "Wu Ben," representing the garrison officials. These stars in the sky are remarkable, representing earthly matters. Consider the "She Ti Liu Xing," located south of the Dipper, responsible for the changing seasons and foretelling fortunes and misfortunes. The She Ti star acts like a great shield, protecting the emperor's throne and symbolizing the nine officials of the court. If the She Ti star shines brightly, the three officials can operate freely; however, if any guest stars approach the She Ti star, the emperor must exercise caution and be more restrained.
Looking further west, there are three stars called "Zhou Ding" (周鼎), which is crucial to the nation's rise and fall. In the middle, there is a prominent star, situated between the Sheti star, symbolizing the heavenly king's throne, serving as the pillar of heaven that oversees the nation's economic matters. North of the "Di Xi" stars, three stars known as "Di Xi" can be found, representing the court's banquets and various ceremonies. North of the "Geng He" star, there are three stars called "Geng He," resembling a long spear in the sky; some say it is the blade of heaven, symbolizing the Hu people's army. If the "Geng He" star shifts, it indicates that troops may be mobilized or a funeral is imminent. If the "Geng He" star disappears, the nation will face the threat of war.
North of the "Geng He" star, there is a star called "Zhao Yao," which is said to resemble a spear and shield, also symbolizing Hu soldiers. Its omens are akin to those of the "Geng He" star. Between the "Zhao Yao" star and the Dipper's ladle of the Northern Dipper, there is a place called "Tian Ku." If the "Zhao Yao" star moves from its position, it heralds a favorable omen of a full national treasury. If the "Zhao Yao" star shines brilliantly yet is misaligned, then the Hu people will refrain from paying tribute. If the "Zhao Yao," "Tian Dong," "Geng He," and "Bei Dou" stars all align, then the Hu people will come to pay homage to China.
To the north of the "Zhaoyao" star, there are two stars called "Xuange," which carry a similar connotation to "Zhaoyao." Some say they represent the northern tribes. If a comet moves to the "Xuange" star, the Hu tribes will suffer a great defeat. To the east of the Big Dipper's ladle, there are three stars called "Tianqiang," also known as "Tianyue." These are weapons bestowed by heaven, positioned on the left side of the Purple Forbidden Enclosure to defend against foreign enemies. To the north of the "Tianqiang" star, there are three stars called "Nuchuang," representing the affairs of the harem and women. Further north, there are five stars called "Tianban," which act as the vanguard in imperial campaigns, symbolizing hidden military strength, conflict, and punishment, also used to defend against foreign enemies. Both "Tianqiang" and "Tianban" are prepared for times of great upheaval. If any of these stars disappear, the country will face turmoil.
Speaking of the heavens, to the east, there are seven stars called "Fukuang," shaped like a basket for mulberry leaves, symbolizing the encouragement of silkworms. Further east, there are another seven stars called "Qigong," located to the east of the Zhaoyao star. These symbolize the heavens, similar to the ancient Three Dukes, overseeing the seven administrations (the seven types of governance in ancient times). In front of the "Qigong," there is a formation of nine stars known as "Guansuo," which is a "prison for the downtrodden," similar to a jail. Some call it "Liansuo," "Yunying," or "Tianlao," all of which pertain to law and the suppression of riots. Within this "prison," there is a star called "Men," indicating whether the prison gate can be opened. If all nine stars shine brightly, the world's prisons will be overflowing; seven stars shining indicates a minor amnesty; five stars shining indicates a major amnesty. If these stars begin to move, axes will be needed; if the center is empty, it will signal a change of dynasty. According to the "Book of Han," there are a total of fifteen stars in this area.
Next, to the east of the "Northern Dipper" is the "Celestial Record" formed by nine stars, representing the nine ministers (senior officials in ancient times). This "Celestial Record" governs the natural order of the universe, handling various disputes. If it shines, there will be an increase in lawsuits; if it dims, government affairs will descend into chaos, national discipline will break down, and if it scatters, disaster may strike, potentially causing earthquakes and landslides. Further east, there are three stars that make up the "Weaving Maiden," who is a celestial maiden overseeing precious things like fruits, silk, and treasures. If the emperor is filial, the deities will be pleased, and the "Weaving Maiden" star will shine brightly, ushering in peace across the land. If the nearby star known as "Rage Corner" shines, the cost of fabric will increase.
To the east, there are four stars called "Jian Tai", like a platform by the water, governing sundials, water clocks, and music. To the west, there are five stars called "Nian Dao", which is the route for emperors' recreation, connecting the Southern and Northern Palaces of the Han Dynasty. Between the "Left and Right Corners" there are two stars called "Officials of the Level Path". To the west of the "Level Path," there is a star called "Jin Xian", responsible for recommending talents. Two stars to the north of Jiao Xiu are called "Tian Tian" (Heavenly Field), and six stars north of Kang Xiu are called "Kang Chi". "Kang" is a boat, "Chi" is water, governing the flow of arrivals and departures. One star north of Di Xiu is called "Tian Niu", responsible for the dew. In the middle of Fang Xiu, there is a star called "Year", guarding it and ensuring the balance of yin and yang. To the west of Fang Xiu, there are two stars in a north-south arrangement, called "Tian Fu", responsible for the royal carriages and horses, like the "Jin Che" and "Gong Che" mentioned in the "Book of Rites". They are also responsible for sacrificial rites. Four stars each of Dong Xian and Xi Xian, to the north of Fang Xiu and Xin Xiu, are the paths of the sun, moon, and five major stars. The gate of Fang Xiu is used to prevent moral decay. It's favorable when the stars shine, but unfavorable when they dim. If the moon and five stars offend it, a conspiracy may arise. Three stars each of Dong Xian and Xi Xian, in a north-south arrangement, are called "Punishment Stars", responsible for atonement. There is also a star called "Jian Bi", in the northeast of Fang Xiu, near Gou Qian, responsible for managing passes and gates.
The Celestial Market, located in the northeast of the Fang and Xin constellations, consists of twenty-two stars. It governs the affairs of weighing and gathering people and is also referred to as the Heavenly Flag Court, primarily overseeing executions. The stars of the Celestial Market shine brightly and are vibrant; if they are bright and plentiful, the year will yield a good harvest; if the stars are few and dim, the year will yield a poor harvest. If Mars lingers in the Celestial Market, there will be the execution of disloyal ministers. There is also a saying that if the Angry Star (Horn constellation) stays in the Celestial Market, it will result in ministers killing their sovereign. If a comet sweeps across the Celestial Market, it indicates a need to relocate markets or even move the capital. If a guest star enters the Celestial Market, it will spark large-scale wars; if the guest star leaves the Celestial Market, a noble will die. The six stars in the middle of the Celestial Market, near the Grain constellation, are known as the Market Tower and Market Office, regulating market prices and measurements. Among them, the Yang star symbolizes wealth, while the Yin star symbolizes gems. If these stars undergo changes, divination will be performed based on their respective domains. The four stars in the northern section of the Celestial Market are known as the Heavenly Measures, governing measurements; the two stars northwest of the Heavenly Measures are referred to as the Market Stalls, overseeing goods such as treasures and jade; the two stars on the inner left side of the Market Gate are called the Carriage Stalls, regulating the area where numerous merchants congregate.
In the Celestial Market, there is a star called Emperor's Throne, located in the center of the Celestial Market, to the west of the Waiting Star, symbolizing the Heavenly Court. If the Emperor's Throne star shines brightly and radiantly, it foretells good fortune for the emperor, and government decrees can be implemented smoothly; if the Emperor's Throne star is weak and dim, it foretells bad omens, often suffered by high-ranking officials. There is also a star called the Waiting Star, located in the northeast of the Emperor's Throne, responsible for monitoring the shifts in Yin and Yang. If the Waiting Star is bright and large, it indicates strong officials and submission of foreign tribes; if the Waiting Star is faint and dim, it means the country is stable; if the Waiting Star vanishes, it signals the monarch's fall; if the Waiting Star moves, the monarch will be restless. The Four Eunuch Stars are located in the southwest of the Emperor's Throne, representing former convicts serving the monarch. If these stars are weak and dim, it is auspicious; if they are bright, it is dangerous, not their usual state, suggesting that eunuchs may encounter difficulties. The Five Dipper Stars are situated south of the Eunuch Stars, responsible for measurements. If the Five Dipper Stars tilt upwards, it indicates that the weights and measures of the world are not unified; if the Five Dipper Stars tilt downwards, it indicates a bountiful harvest. The Ancestral Two Stars are located in the southeast of the Emperor's Throne, representing the royal officials. If a comet stays near the Ancestral star, or if the Ancestral star loses its color, disasters will strike the Ancestral officials; if a guest star stays near the Ancestral star and moves, there will be changes among the emperor's relatives; if a guest star stays near the Ancestral star for a long time, nobles will die. The Ancestral Star Two Stars are located to the east of the Waiting Star, symbolizing the emperor's blood relatives and loyal ministers. If a guest star stays near the Ancestral Star, internal strife will arise within the royal family. The two stars in the northeast of the Celestial Market are called Bo Du and Tu Si, responsible for textiles and butchery, respectively. The Four Tianjiang Stars are found north of the Tail Mansion, responsible for the Taiyin. If the Tianjiang star is incomplete, the rivers and passes of the world will be blocked; if the Tianjiang star is bright and shaky, there will be floods and wars; if the Tianjiang star is uneven, horse prices will increase; if Mars stays near the Tianjiang star, a new king will be established; if a guest star approaches the Tianjiang star, the river will be severed.
In the sky, there is a constellation called Tianjiao Eight Stars, located to the west of the Southern Dipper. It governs closures, akin to a door lock. There is also a constellation called Jianxing, consisting of six stars, located to the north of the Southern Dipper, also known as Tianqi, which acts as the capital's checkpoint in the heavens. Jianxing is associated with strategic planning, the celestial war drums, and the heavenly war horses. The two stars to the south are the celestial warehouses; the two stars in the middle are the marketplace and the armory; the two stars above are ornaments on the flagpoles. Between the Southern Dipper and Jianxing is the Three Lights Avenue. If these stars are in turmoil, people on earth will endure hardship. If the moon's halo envelops them, dragons may emerge, and cattle and horses will fall ill. If the moon and the five planets conflict with them, ministers will scheme against each other, and subordinates will plot treachery; it will also lead to blocked passes and major floods. The four stars in the southeast are called Dog Country, representing the Xianbei, Wuwan, and Wozhu tribes. If Mars stays there, there will be turmoil among foreign tribes; if Venus retrogrades and stays there, Dog Country will experience internal strife; if a guest star invades there, notorious bandits will arise, and even the king could be slain. The two stars to the north of Dog Country are called Tianji, which regulate the passage of time.
The Tian Bian Jiu Xing is located to the north of the Jian Xing. These stars represent officials responsible for the market, overseeing the stalls and shops in the market, similar to managing the market register, which allows them to know what precious goods are available. If these stars shine brightly, it is a good omen; if a comet invades them, food prices will rise, and prisoners will rebel. The He Gu San Xing and Qi Jiu Xing, found to the north of the Qian Niu Xing, represent the celestial war drums, overseeing the military drums and armory. Some refer to these as the Three Martial Stars, representing the three generals of the emperor. The largest star in the middle represents the Grand Marshal, while the star on the left represents the Left Marshal, and the star on the right represents the Right Marshal. The Left Marshal Star is to the south, thus it is tasked with defending the passes, repelling foreign enemies, and signaling war and strategy. The Qi Xing serves as the flag of the Tian Gu, acting as a symbol and emblem. The Left Flag Jiu Xing is to the left of the drum. If the war drum stands straight and shines bright, with a yellow hue, it will signify good omens; if it is crooked, there will be military disasters. If this star exhibits turbulence, horses will become costly; if it becomes turbulent, there will be war; if it appears curved, the commander risks making mistakes and losing the upper hand. If the flag star is ominous, a rebellion is likely to ensue. At the flag's end, four stars are arranged from north to south, known as Tian Fu, with 'Fu' meaning drumstick. If these stars do not shine brightly, it may result in inaccuracies in timekeeping. They are near He Gu; if the Fu and Gu are aligned properly, they are all utilized for drumming. The Li Zhu Wu Xing, located north of Xu Nv, represents the palace of Xu Nv Xing and symbolizes female stars. If these stars are out of alignment, the harem will descend into chaos. If a guest star disrupts them, the harem will face peril. If these stars are in harmony, the harem will remain peaceful; if issues arise, such as a guest star intruding, the harem is sure to face turmoil and significant events will unfold.
The two stars to the north of the Void are called the Star of Life, the two stars further north are called Si Lu, the next two stars further north are called Si Wei, and the two stars at the very north are called Si Fei. The Star of Life governs rewards and punishments and can eliminate disasters; Si Lu increases lifespan and blessings, hence it is located north of the Six Celestial Lords. If one offends Si Wei, it leads to arrogance and indulgence in behavior, ultimately resulting in failure; Si Fei, on the other hand, is known for enforcing laws with bias.
North of the Void is a star cluster known as the Hulu Stars, which governs schemes, the harem, and food crops. When bright, it indicates a bountiful harvest; when dim, it signals a poor year, resulting in diminished influence in the harem. If these stars behave abnormally without reason, mountains will tremble, and valleys will overflow. Nearby is a star known as the Failed Gourd, which pertains to agriculture.
The Nine Stars of Tianjin are like a bridge that connects all directions. If one star is unprepared, the routes through Tianjin become obstructed. When the stars are bright and active, war erupts like quicksand, leading to countless casualties and chaos. If they are dim and uneven, horses become as worthless as death. If the Tianjin star disappears, water-related disasters will occur, or water bandits may rise to power.
To the east near the river, there are seven stars called the Chariot Office, which govern vehicles and officials. Southeast of the Chariot Office, there are five stars called the Human Star, which stabilize the populace and bring distant people to submission. Some also call it the "Reclining Star," which primarily serves to prevent promiscuity. South of the Human Star, there are three stars called Internal Analysis, and southeast, there are four stars called Chuju, which oversee military supplies. If the guest star enters these constellations, war will break out, and grain from across the country will be requisitioned.
To the north of Tianjin, there are four stars arranged like a balance, called Xizhong, the ancient official in charge of vehicles.
It is said that there are twenty-two stars in the sky arranged in the shape of a soaring serpent, located to the north of the Ying Shi star. This Tian She star governs waterborne insects. If this star shines particularly brightly, this is not a good sign, indicating that trouble is coming; if a guest star approaches it, a flood is sure to come, and the harvest will definitely be poor.
Furthermore, there are five stars called Wangliang, located to the north of the Kui star, in the middle of the Yellow River, symbolizing the emperor's carriage and the imperial officials. Four of these stars are called Heavenly Steed, and next to them is a star called Wangliang, also known as Tianma. If the Wangliang star moves, it signifies galloping horses and many carriages. Some also say that the Wangliang star is a bridge in the sky, governing wind, rain, and waterways, so sometimes people use it to divine the fortune of bridges. If the Wangliang star moves, it indicates war; others say it means a horse is sick. If a guest star approaches it, then the bridge will be impassable.
The star in front is called “Ce,” which is the whip of the horse that drives Wangliang, governing the emperor's coachman, located right next to the Wangliang star. If it shifts to behind the horse, it signifies "galloping horses," signaling that carriages will be everywhere.
Then there are the Ge Dao Six Stars, in front of Wang Liang Xing, which is the celestial road. It stretches from the Zi Wei Palace all the way to the Yellow River, serving as the pathway for celestial beings. Some say that the Ge Dao Xing governs travel, being the road for the emperor to visit other palaces. Others say that the Ge Dao Xing can ward off disasters and atone for sins. There are also those who refer to it as Wang Liang Qi or Zi Gong Qi, which is most feared to be disturbed, as the flag star is used by the army.
There is only one Fu Lu Xing, located south of Ge Dao Xing, which serves as an alternative route. It acts as a backup for Ge Dao Xing; if anything happens to Ge Dao Xing, it can step in. Some say it is called Tai Pu, governing wind and rain, and also has the meaning of attendants.
Finally, to the north of Dong Bi Xing are ten stars known as Tian Jiao, which oversee horse management, akin to modern relay stations, overseeing the transmission of orders, setting up relay stations, and running day and night, depicting their swift movements, racing against time like water dripping from a leaky jug.
The twelve celestial constellations are known as Tian Jiang Jun, located to the north of Lou Su, overseeing military matters. The largest star at the center is the Grand General of Heaven; the smaller stars around it are his soldiers and officials. If the light of the Grand General's star trembles, it signifies that war is imminent; the Grand General must go to battle. If the light of the smaller stars is dimmed, that also indicates war. To the south, there is a star called Jun Nan Men, which regulates army movements.
There are eight Tai Ling stars situated north of Wei Su. Here, 'Ling' refers to a tomb. The star in Tai Ling that resembles a curled tongue is called Ji Jing, overseeing significant funerals. If the central star of Ji Jing vanishes, it means someone is destined to die in the feudal states, the common people will endure many illnesses, and there will also be wars, resulting in food shortages; if fewer stars appear in the center of Ji Jing, food will be distributed. If this star shines brightly, it indicates that civil engineering projects will be constructed. The star in the middle of Tai Ling is called Ji Shi; if it shines brightly, it signifies that deaths will be as numerous as mountains.
There are nine stars in the Tian Chuan constellation, located to the north of the Tai Ling star, in the Yellow River. One of them is called Zhou Xing, responsible for ferry crossings, overseeing transportation issues as well as water and drought disasters. If this star is not in the Han River basin, the ferry crossings on the Yellow River will be disrupted. If the four central stars shine evenly and brightly, the world will enjoy peace; if they don't, it will lead to war or death. If the guest comet moves in and out of the Tian Chuan constellation, there will be flooding and war. The central star of the Tian Chuan constellation is called Ji Shui, specifically responsible for forecasting floods. The two stars to the west of the Mausoleum are called Tian Jie, the path of the sun, moon, and stars, overseeing the conditions at the passes and bridges. The star to the west of Tian Jie is the moon. The six stars of the Juan She constellation, located in the north, oversee people's speech and can indicate if someone is speaking ill. If these six stars are curved, it is a good omen; if they are straight and turbulent, disputes will arise. The central star of the Juan She constellation is called Tian Chan, responsible for witch doctors.
The Big Dipper consists of five stars, while the Three Enclosures consists of nine stars, all located north of the Dipper. The Big Dipper is where the Five Emperors reside, which govern the emperor's five weapons and the abundance or scarcity of the five grains. The largest star in the northwest is known as Tianku, which governs Jupiter and the state of Qin. The star in the northeast is known as Yu, which governs Mars and the states of Yan and Zhao. The star in the east is known as Tiancang, which governs Saturn and the states of Lu and Wei. The star in the southeast is known as Sikong, which governs Venus and the state of Chu. The star in the southwest is known as Qingsu, which governs Mars and the state of Wei. If any changes occur among these stars, predictions of fortune or misfortune are made according to the states they govern. The Three Enclosures, which are named Sanquan, Xiu, and Qi, indicate the emperor has received heavenly favor if the Big Dipper shines brightly and evenly. If both the Big Dipper and the Three Enclosures shine brightly, grand ceremonies can be held. There are five stars in the center of the Big Dipper, collectively known as Tianhuang. South of Tianhuang, there are three stars known as Xianchi, which means "fish pond." If the moon and five stars enter Tianhuang, wars may break out, roads may be blocked, causing chaos and potential dynastic changes. If Xianchi shines brightly, dragons may fall dead, and beasts may harm people, as if preparing for war. In the sky, there are many stars, each overseeing earthly matters. For example, the six stars south of the Big Dipper, referred to as "Kings," predict the rise and fall of vassal states. The five stars to the west, known as "Li Shi," may indicate impending war if Venus or other wandering stars appear. The eight stars to the north, referred to as "Eight Valleys," oversee the harvest of grains, where the disappearance of one star signifies a poor harvest.
There is also a "Tian Guan Xing," south of the Wuche Star, also referred to as "Tian Men." The sun and moon both pass through here, overseeing border matters and regulating access. If the "Mangjiao" star appears, it also indicates a war is coming; if the five stars gather here, it would be catastrophic, and many prominent figures would perish.
In front of the Dongjing Constellation, the four stars are called "Siguai," specifically overseeing the changes in the heavens, earth, sun, moon, and stars, as well as anomalies of birds, beasts, plants, and trees. If a wise ruler knows these omens, they will quickly cultivate virtue and accumulate blessings in hopes of peace. The nine stars northwest of the "Siguai" star are called "Zuoqi," representing the hierarchy of rulers and ministers. The four stars west of the "Zuoqi" star are called "Tiangao," symbolizing lofty platforms and pavilions that offer distant views. The star west of the "Tiangao" star is called "Tianhe," overseeing the demons and spirits lurking in the mountains and forests.
The South River and North River each has three stars flanking them, sandwiched beside the Dongjing star. The "Tiangao" star, also known as the celestial gateway, manages passes and bridges. The South River star, also known as Nanshu, Nangong, Yangmen, Yuemen, and Quanxing, rules over fire; the North River star, also known as Beishu, Beigong, Yinmen, Humen, and Hengxing, rules over water. The sun, moon, and five stars usually move between these two rivers; if the stars in these two rivers are troubled, then China will go to war. The three stars of the South River are also called "Queqiu," symbolizing the view beyond the palace gates.
The five stars north of the Dongjing star are called "Wuzhuhou," and they oversee the evaluation of officials, urging people to exercise caution and prudence, and also manage yin and yang, monitor gains and losses, and even discern the emperor's thoughts. These five stars represent the Imperial Tutor, Imperial Friend, Three Dukes, Scholar, and Court Astrologer; these five individuals frequently assist the emperor in decision-making. If these five stars shine brightly and are nourished, the realm will enjoy peace; if they appear dim and lifeless, calamities will follow.
The three stars to the south of the "Five Dukes" are called "Heavenly Zun," which oversees the supply of food and drink; the "Accumulated Fire" star is to the east of the "Accumulated Water" star and manages the kitchen supply; the "Water Level" star is to the east of the Dongjing star and oversees water resources. If a guest star moves to Mercury or Mars, it could cause trouble, and rivers would flood as a result.
It is said that there are the Seventeen Stars of Xuanyuan in the sky, north of the Big Dipper. This Xuanyuan is the deity of the Yellow Emperor, the incarnation of the Yellow Dragon. It oversees the harem and symbolizes the ranks of civil officials. One of the stars is called Dongling Star, also known as the Star of Authority, which oversees thunderstorms. The largest star to the south symbolizes the main female figure. Counting north, the first star represents the concubine; counting north again, the next star represents the general; the remaining stars are all concubines and similar figures. The small star next to the main female figure represents the female officials. The small star to the left represents the minor officials, specifically the family of the lesser consort; the large star to the right represents the major officials, which represents the family of the empress dowager. These stars should ideally be yellowish, small, and bright.
To the right and below the Xuanyuan star, there are three stars called the Wine Flag, which serves as the banner for the wine officials, overseeing the court banquets and food. If all five stars were to gather near the Wine Flag, then there would be grand banquets in the world, with plenty of wine, meat, and treasures given to the dukes and noble families. To the south of the Wine Flag, there are two stars called Heavenly Minister, which symbolize the prime minister. To the west of the Xuanyuan star, there are four stars called Zhao, which symbolize beacon fires, representing border alarms.
To the north of the lamp, there are four stars called Nei Ping. The four stars of Shaowei are located to the west of Taowei, representing the ranks of scholars and officials. Some say it represents a hermit, or the assistant of the emperor; others say it is a councilor, while others say it is in charge of guarding the palace gates. Specifically, the southernmost star represents a hermit, the second star represents a councilor, the third star represents a scholar, and the fourth star represents a gentleman. If these four stars appear large and yellow, it indicates that a wise man will be recommended. If the moon and the five stars come near here, the hermit and the female protagonist will face misfortune, and the prime minister will be replaced. There are four stars to the south, called Changyuan, representing the borders of the nation and the nomads. If Mars appears in this position, the nomads will invade the Central Plains; if Venus comes here, the nine ministers will plot.
