Main achievements
Invention
Seismometer
Seismometer structure
AD 132 (the first year of Yangjia) , Zhang Heng invented the earliest seismograph during his tenure as Taishi Ling, called the Houfeng seismograph. According to the "Book of the Later Han·Zhang Heng Biography": The seismometer is made of fine copper, with a diameter of eight feet, a protruding top cover, shaped like a wine bottle, and decorated with images of turtles, birds and beasts in seal script. There is a big pillar in the middle, with eight paths running beside it, which is used to shut down the engine. It has eight directions, and in each direction there is a dragon with a copper bead in its mouth. Under each dragon there is a toad corresponding to it. If an earthquake occurs in any direction, the copper beads contained in the dragon's mouth in that direction will fall into the toad's mouth, and the direction of the earthquake can be determined from this. After testing, it was in accordance with the established system, and it was as good as God. This has never happened since there were records in books. Once upon a time, when a dragon's message came out, the earth did not move, and the scholars in Luoyang blamed it for not believing it. A few days later, the messenger came, and sure enough, an earthquake occurred in Longxi, and everyone was convinced of its miracle. From then on, the imperial court ordered historians to record the places where earthquakes occurred.
As for the structure of the seismometer, there are two popular versions: Wang Zhenduo's model, that is, the "Du Zhu" is a cylinder shaped like an inverted wine bottle, and the mechanism that controls the dragon's mouth is around the "Du Zhu". This model has been basically rejected. Another model was proposed by Feng Rui of the Seismological Bureau, that is, the "Du Zhu" is a hanging pendulum (see Yuan Hong's "Later Han Dynasty"). There is a small ball below the pendulum, and the ball is located at the intersection of the "meter" shaped slides (i.e. "The Later Han Dynasty"). ("Guan" mentioned in the "Book·Zhang Heng Biography"), during an earthquake, the "Du Zhu" moves the small ball, and the small ball fires the mechanism that controls the dragon's mouth, causing the dragon's mouth to open. In addition, Feng Rui's model also changed the toad from facing the bottle body to facing away from the bottle body and acting as the feet of the instrument. The model has been simulated and tested, and the results are consistent with historical records.
There are frequent earthquakes in the world, but it was only after the 19th century that instruments could be used to observe earthquakes abroad. Houfeng seismograph is the ancestor of seismographs in the world. Although its function is still limited to measuring the approximate location of the epicenter, it surpasses the development of world science and technology by about 1800 years.
Armillary sphere
Leaking water to armillary sphere is a water-borne muddy phenomenon. Use a copper ball with a diameter of more than four feet. The ball is engraved with the twenty-eight constellations, Chinese and foreign star officials, the ecliptic equator, the north and south poles, the twenty-four solar terms, the permanent display circle, the permanent hidden circle, etc. to form a complete image, and then use a set of rotating machinery , combining the Hunyianxiang and the Clepsydra. The clepsydra water is used to control the muddy image so that it rotates synchronously with the celestial sphere to show the diurnal movements of the starry sky, such as the emergence and emergence of stars and the midheaven. It also has an affiliated mechanism, the Rui Lun Ming Cai, which is a mechanical calendar connected by a transmission device and the Universal Image. From the beginning of each month, one leaf grows every day; after half a month, one leaf falls every day. The two-stage clepsydra it uses is the earliest known record of a two-stage clepsydra.
Zhang Heng once wrote an article after creating the armillary sphere. The full text of this article has been lost. It was only in the Liang Dynasty that Liu Zhao made a large quotation when he annotated "Book of the Later Han·Lü Li Zhi" and passed it down to the world. Liu Zhao's note titled this passage "Zhang Heng's Armillary Sphere". Calling it the "armillary sphere" may be a simplification made by Liu Zhao. In ancient times, the naming of instruments was not strict. Although later generations standardized the term "armillary sphere" to specifically refer to observation instruments, before the Sui and Tang Dynasties, "armillary sphere" could also be used for performance instruments.
Rui Lun Pod
Rui Lun Pod is an automatic calendar ingeniously created by Zhang Heng. It imitates the characteristics of the pod of a strange tree in mythology. It relies on the action of running water. Starting from the first day of each month, one day One leaf appears, and by the full moon all 15 leaves have appeared, and then one leaf is put away every day, until the end of the month, and the cycle opens and closes. This myth tortuously reflects the progress of the astronomical calendar during the reign of Emperor Yao. Zhang Heng's mechanical device was inspired by this myth. It is said that "it waxes and wanes with the moon, rises and falls according to the calendar", and its function is equivalent to the date display in today's clocks.
Compass car
The compass car manufactured by Zhang Heng uses mechanical principles and gear transmission, and consists of a two-wheeled single-column car. A gear system with automatic clutch is used in the carriage, and a wood-carved immortal is placed on the upper layer of the carriage shell. No matter which direction the car turns, the outstretched arm of the wooden figure points to the south.
The Ji-Li Drum Cart
The Ji-Li Drum Cart created by Zhang Heng is a machine used to calculate mileage. According to the "Annotation of Ancient and Modern Times": "The cart has two floors, and there are wooden figures on it. The lower floor beats drums after traveling for one mile, and the upper floor beats bangles after traveling for ten miles." The manufacturing method of the drum car is the same as that of the compass car, and the principle of differential gear used is more than 1800 years earlier than the West.
Flying Solo Wood Sculpture
Zhang Heng made Solitary Wood Sculpture, which imitates the gliding wing design of birds soaring high in the sky.
Topographic Map
Zhang Heng also studied geography and drew a topographic map based on his research and inspection experience. The third volume of "Records of Famous Paintings of the Past Dynasties" written by Zhang Yanyuan of the Tang Dynasty says: "Heng tried to make topographic maps, which still existed in the Tang Dynasty."
Calendar
Zhang Heng once participated in the 2nd year of Yanguang reign of Emperor An of the Han Dynasty ( There was a great calendar discussion in AD 123. According to the "Book of the Later Han Dynasty·Lü Li Zhi", Zhang Heng was the minister at that time. The cause of this great discussion was that some people, based on superstitious concepts such as prophecies and disasters, criticized the more scientific "Sifen Calendar" of the Eastern Han Dynasty that was in use at that time, and proposed that the "Jiayin Yuan Calendar" which was suitable for prophecies should be used instead. Some people started from the view that Emperor Wu of the Han Dynasty "repelled the barbarians and expanded the territory and enjoyed the country for a long time" and believed that we should go back and adopt the "Taichu Calendar".
Zhang Heng and another minister, Zhou Xing, criticized and challenged the above two opinions, leaving the proposers of these two wrong opinions either speechless or wrong in their answers, thus contributing to preventing the retrogression of the calendar. During the discussion, Zhang Heng and Zhou Xing also studied many years of astronomical observation records, compared them with the theoretical calculations of various calendars, and proposed an appraisal. They believed that the "Nine Ways of Law" was the most precise and recommended its adoption. Indeed, the numerical values ??of the length of the tropical year and the length of the synodic moon in the "Nine Paths Method" are more precise than those in the "Taichu Calendar" and the Eastern Han Dynasty's "Four Points Calendar". [16]
Furthermore, "Nine Ways of Law" admits that the speed of the moon is uneven, while other calendars at that time only calculated based on the uniform speed of the moon. Therefore, the conjunction and lunar calendar calculated by the "Nine Ways of Law" are more consistent with astronomical reality than other calendars at that time. However, if calculated according to the "Nine Ways of Law", it is possible that there will be three consecutive 30-day big months, or two consecutive 29-day small moons, etc. According to the calendar arrangement that people have been accustomed to for thousands of years, the big and small months have always been connected. At most, two big months have been connected once every 17 months, and there have never been three big months connected, let alone two small months. connected phenomena. Therefore, the phenomenon of connecting three big months or two small months brought about by the "Nine Ways of Law" is difficult for people with conservative habits to accept. In this way, Zhang Heng and Zhou Xing's suggestion to adopt the "Nine Ways of Law" was the most reasonable and progressive one at the time, but it failed to pass in this great discussion. This is a loss in Chinese history. The adoption of uneven monthly movements into the calendar was delayed for more than half a century. It was not until Liu Hong's "Qianxiang Calendar" that it was officially adopted for the first time.
"Ling Xian" is Zhang Heng's representative work on astronomy, which comprehensively reflects Zhang Heng's achievements and development in astronomy. The original text was quoted by Liu Zhao's annotation in "Book of the Later Han·Tianwen Zhi" and passed down to the world. The key points of astronomy introduced in the article are as follows:
Zhang Heng believes that the universe is infinite and the movements of celestial bodies are regular; moonlight is the reflection of sunlight, lunar eclipses are caused by the earth covering the sun, and the moon orbits the earth and rises and falls. . He recognized certain laws of the movement of the sun (should be the revolution of the earth), and correctly explained the causes of long nights in winter, short nights in summer, and the causes of day and night at the vernal and autumnal equinoxes. He pointed out that there were 2,500 stars that could be seen in the Central Plains, which was slightly closer to what people know today. After observing the movement of certain celestial bodies, he came to the conclusion that the length of a day is 365 degrees and one quarter, which is consistent with the value measured in modern times that the earth takes 365 days, 5 hours, 48 ??minutes and 46 seconds to orbit the sun. Not much different.
Literature
Zhang Heng made a huge contribution to the history of the development of Han Fu. During his career as a fu writer, he comprehensively inherited the Fu ideas and expression techniques of previous generations of Fu masters. The big fu is based on Sima Xiangru's "Zixu" and the more recent "Er Capital Fu" by Ban Gu. For seven styles, Bu Meicheng's "Qi Fa" and Fu Yi's "Qi Ji" were used as "Qibian"; while for Wen Fu, "Ying Jian" was based on Dongfang Shuo's "Answering Guests" and Ban Gu's "Answering Guests". Others include "Nandu Fu" inspired by Yang Xiong's "Shu Du Fu"; and "Wu Fu" based on Fu Yi's "Wu Fu". Although the above examples are all simulations, and their achievements vary, they do demonstrate artistic creativity to varying degrees. What's even more outstanding is that Zhang Hengng was able to integrate and creatively use "Guitian Fu" to realize the main body of Han Fu from spreading out the prose, adding extravagance, and focusing on objects to overwhelm emotions, to fresh, refreshing, short and simple. The transformation of conciseness and situational interaction has opened up the creative era of lyrical poems and injected great vitality into narrative poems. Most of Zhang Heng's works show the denial and criticism of reality. He explores the mysterious philosophy of life and also explores a living space that is consistent with his ideals and personality [17]. The representative works of Zhang Heng's Fu have always been recognized as "Er Jing Fu", "Si Xuan Fu" and "Guitian Fu".
"The Literary Mind and the Carving of Dragons" states that "Ziyang (Yang Xiong) Ma (Sima Xiangru) Zhang (Zhang Heng) Cai (Cai Yong), Chong Sheng Li Ci, such as the Song Dynasty painting Wu Ye, carved shape The engraving method, the beautiful sentences and the profound words flow together, and the unexpected meaning and elegant rhyme are both expressed." [18] It is also known as "Zhang Heng is Tongzhu, Cai Yong is elegant, and the literature and history are elegant, so the bamboos and cypresses are different from each other. "Tongzhen, gold and jade are of different qualities and are all treasures." [19]
Zhang Heng once wrote "Executes of Zhou Officials", and Cui Yuan believes that there is no difference with the explanations of other Confucian scholars. He also wanted to follow Confucius's "Yi" to correct the defects of "彖" and "Xiang", but it was never completed. His poems, fus, inscriptions, seven-character works, "Lingxian", "Yingjian", "Qibian", "Xungao", "Xuantu" (one work "Xuantu") and other works, ***32 articles. [20]
"Han Shi" contains nine poems. [21] "Sui Shu·Jing Ji Zhi" contains 14 volumes of "Zhang Heng Collection", which has been lost for a long time. Zhang Pu of Ming Dynasty compiled "Zhang Hejian Collection", which was included in "Collection of One Hundred and Three Masters of Han, Wei and Six Dynasties". Volumes 52-55 of Quanhou Hanwen include his poems, poems and memorials.
History
During the reign of Emperor Yongchu of the Han Dynasty (107-113), Liu Zhen, the visitor servant, Liu Fanjun, the school secretary, and others compiled the "Han Ji" in Dongguan. Therefore, after studying the etiquette of the Han family, Shangshu asked Zhang Heng to participate in the discussion. When the two of them passed away, Zhang Heng sighed and wanted to complete the matter. When he was appointed as a minister, Shangshu asked Dongguan to collect and inspect the relics and make every effort to repair them. There are also more than ten things recorded by superiors Ma Qian and Ban Gu that are inconsistent with the classics. It is also believed that the original biography of Wang Mang should only record the usurpation of the throne. As for chronicling the year and recording disasters and auspiciousness, it should be renamed "The Original Records of the Empress of the Yuan Dynasty". The people had no objections to the idea that Emperor Gengshi was on the throne.
Emperor Guangwu was originally a general of Emperor Gengshi, and he came to the throne later. The Gengshi reign should be built before Guangwu. I submitted letters several times, but none were accepted. Most of his later writings were not detailed in classics, which was a pity for the people at the time.
Liu Xie once commented on this in "Wen Xin Diao Long": "Zhang Heng was a historian, but he was confused and moved to Gu. After Yuan Ping, he wanted to establish a record, which was also very wrong. Looking for a son Although Hong is a hypocrite, he should be the heir of filial piety; the son is sincere and humble, but he will inherit the body of Emperor Ping; two sons can be remembered, so why should there be two queens?"
Thoughts
Eastern Han Dynasty Prophecy The study of Confucianism became popular in the world. After the founding of the Eastern Han Dynasty, Confucian scholars strived to learn from it and even attached it to monstrous words. Zhang Heng believed that the plan was illusory and not the way of a sage. Therefore, Shangshu believed that "the prophecies of the country are false and are not the law of the saints." He also believed that "these are all deceiving the world and disregarding the customs... It is better to collect the prophecies of the country. They are forbidden." Jian Bozan called Zhang Heng "the Outline of Chinese History". An anti-prophecy thinker. ”
Mechanical
Zhang Heng mastered superb mechanical technology. It is said that he also made two magical artifacts at that time. One is a machine with three wheels that can rotate; the other is a wooden sculpture that can fly in the sky.
As for wood carvings, "Mozi Lu Wen" records: "Gong Shuzi whittled bamboo and wood to make magpies. When they were completed, they flew and stayed there for three days." "Liezi·Tangwen" and "Han Feizi· "Wai Chu Shuo" records that Mozi himself also made a wooden kite that could fly. These wood magpies or kites are probably a bird-like kite. It cannot be other aircraft equipped with power machines, such as today's aircraft. Because at that time it was impossible to have a power machine that could run continuously for one or even three days. Zhang Heng’s wood carvings are probably also kind of kites. However, the Northern Song Dynasty's book "Taiping Yulan·Jiu Min Jiu" quoted a paragraph from "The Biography of Scholars" and said: "Zhang Heng tried to make a wooden bird, using feathers as a feather, and using a machine in his belly, it could fly several miles." Here it says " "It can fly for several miles". Therefore, some authors in the past considered it to be an aircraft-like aircraft. However, the power machine installed on the aircraft must be light enough and powerful enough, and the aircraft itself must have a certain shape suitable for taking off and rising, etc. None of these conditions could be achieved in Zhang Heng's era. Therefore, even if Zhang Heng's woodcarvings really "operate a machine inside the belly," then the machine will not be a power machine, but a control mechanism installed on the kite and controlled by wires to fly.
There have been different opinions since ancient times regarding machines with three wheels that can rotate on their own. Wang Yinglin, a scholar of the Southern Song Dynasty, believes that it is a kind of drum car. This kind of car uses a set of gear trains to transmit the movement of the axle when the cart rotates to the arm of a wooden man, so that it beats the drum when it passes one mile. This idea does not seem to be consistent with the meaning of "three wheels can rotate". The action of drumming is generally not regarded as turning. Another opinion is that it is a guide car. Wang Xianqian of the Qing Dynasty quoted "Book of Song·Book of Rites·Zhi" in "Anthology of Later Han Shu·Zhang Heng Biography": "The compass was first made by Zhou Gong, and Zhang Hengshi re-created it" (Note: This is an excerpt from "Book of Song··Zhi·Li", in fact Not the original text). Therefore, the image of the compass is more consistent with the word "rotation", because no matter how the wheels below rotate, people on the car can only see the fingers of the wooden compass turning south automatically.
In short, Zhang Heng is very skilled in mechanical technology. "Taiping Yulan·Jiu Min Jiu" quoted Ge Hong of the Jin Dynasty's "Baopuzi": "The Wood Sages: Zhang Heng and Ma Jun are also." Gao Sisun's "Wei Lue" also said that "Zhang Heng and Ma Zhong are the wood saints" Holy'. "
Mathematics
"Book of the Later Han Dynasty" mentioned that Zhang Heng once wrote a book called "Suan Wang Lun". This book was lost as late as the Tang Dynasty, so much so that Li Xian, the prince of Zhanghuai in the Tang Dynasty, suspected that Zhang Heng had not written this book, but calculated it because "Lingxian" was in the Internet world, so it was called "Lingxian Suanwang Lun". From Liu Hui's annotation on question 24 of Chapter 24 of "Nine Chapters on Arithmetic Shao Guang", we know that there is the so-called "Zhang Heng's calculation". Therefore, it should be affirmed that Zhang Heng wrote a mathematical work. From this annotation by Liu Hui, we can know that Zhang Heng named the cube as prime and the sphere as hun. He has studied the circumscribed cubic volume and inscribed cubic volume of the ball, studied the volume of the ball, and also set the value of pi as the square root of 10. This value is relatively rough, but it is the first Chinese theory to calculate the value of π. . In addition, if according to Qian Baocong's collation of "Lingxian": "The diameter (of the sun and the moon) is one-seven hundredth of the day's circumference, and its breadth is one-two hundred and thirty-two", then the value of π at that time was equal to 730 /232=3.1466, which is more precise than the square root of 10. However, Qian Baocong's collation does not seem to be consistent with Zhang Heng's original figures.
Painting
Zhang Heng believed that painters like some unrealistic things because they can use them to fictionalize and imagine. He said in an epigraph during the reign of Emperor Shun of the Han Dynasty: " For example, he is like a painter, who hates pictures of dogs and horses but loves to create ghosts. His sincerity is difficult to describe, but his hypocrisy is endless." [26] Zhang Heng's paintings are no longer extant. The "Records of Famous Paintings in the Past" by Zhang Yanyuan of the Tang Dynasty calls him "extraordinary talent." , clever in nature, good at painting, and "Zhang Heng wrote "Topographic Map", which still existed in the Tang Dynasty.
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