In seismology, he invented the "seismograph", which is the first instrument in the world to measure earthquakes and directions, more than 700 years before Europe. In astronomy, he invented the "armillary sphere", which is the world's first large-scale astronomical instrument driven by water to observe stars. He wrote books such as Notes on the Huntianyi Instrument and Lingxian, drew a complete star chart, and put forward the scientific conclusion that "moonlight is born in the sun". In geography, he drew a complete topographic map and developed "back-bulging cart" and "pulling cart". In mathematics, he wrote The Theory of Calculation, and calculated the values of pi between 3. 1466 and 3. 1622. It is amazing that such an accurate calculation can be made over 1800 years ago. In meteorology, he created the "Hou Fengyi", which is an instrument to predict the wind and direction, more than 65,438+0,000 years earlier than the hyacinthus orientalis chicken in the west. In mechanics, his "single wood carving" is the earliest aircraft in the world, as well as plans (solar shadow devices) and activity calendars. In literature, he is a brilliant star in the history of China literature. The representative works "Tokyo Fu" and "Xijing Fu" are collectively called "Erjing Fu", which describes the prosperous scenes of Chang 'an and Luoyang in the Eastern Han Dynasty and satirizes the dissolute and shameless parasitic life of bureaucrats and nobles. Du Nan Fu vividly describes the social outlook, natural scenery and folk customs of Nanyang County at that time. In addition, there are more than 30 articles such as Return to Tianfu, Four Fu Xuan and Four Xi History. In art, he ranks first among the six famous painters in the Eastern Han Dynasty.
Jia Sixie, the author of Qi Yao Min Shu, was an intermediate official in the late Northern Wei Dynasty (386-535). The natural conditions described in his book show that he lived in Hebei or Shandong, and his masterpiece Chef was completed between 530 and 540. Besides, little is known about his life story.
Shen Kuo is proficient in astronomy, mathematics, physics, chemistry, biology, geography, agriculture and medicine; He is also an outstanding engineer, excellent strategist, diplomat and politician. At the same time, he is knowledgeable, good at writing and proficient in other people's calendars, music, medicine, divination and so on. Meng Qian Bi Tan, written in his later years, recorded in detail the outstanding contributions of working people in science and technology and their own research results, reflecting the brilliant achievements of natural science in ancient China, especially in the Northern Song Dynasty. Meng Qian's pen talk is not only an academic treasure house in ancient China, but also occupies an important position in the history of world culture.
Zhang Sui: During the Kaiyuan period, Emperor Xuanzong of the Tang Dynasty ordered Zhang Sui to preside over the revision of the calendar. In the practice of revising the calendar, in order to measure the positions of the sun, the moon and the stars in their respective orbits and master their laws of motion, Liang Lingzan and * * made the "Huntian Bronze Instrument" and "Zodiac Sky Patrol Instrument" for observing astronomical phenomena. The armillary sphere was made on the basis of Zhang Heng's armillary sphere in the Han Dynasty, with stars painted on it. The instrument runs on water, day and night, which is consistent with the sky. There are also two wooden statues, one beating the drum at all times and the other ringing the bell every morning, which are more accurate than Zhang Heng's "The Armageddon". The purpose of "Zodiac Navigator" is to directly measure the coordinate positions of the sun, moon and stars in orbit when observing celestial phenomena. Zhang Sui used these two instruments to study astronomy effectively.
Before Zhang Sui, astronomers, including great astronomers like Zhang Heng, thought that stars were stationary. However, Zhang Sui re-measured the positions of 150 stars with instruments such as "Huntian Bronze" and "Zodiac Sky Patrol Instrument", and repeatedly measured the degrees for 28 nights from the celestial north pole. So as to find the stars moving. According to this fact, Zhang Sui deduced that the stars on the celestial body must be moving. So he overthrew the previous conclusion that stars were motionless, and Zhang Sui became the first person to discover the movement of stars in China. Harley, a British astronomer (A.D. 1656―― 1742) also put forward the idea that stars move by themselves, but it was more than a thousand years later than Zhang Sui's discovery.
Zhang Sui is a scientist who attaches importance to practice, and the scientific method he adopted has a decisive role in his achievements. Zhang Sui and Nangong said that together with others, they measured the solar shadow with a benchmark and calculated the relationship between the position of the sun and the solar terms. Zhang Sui has designed and manufactured the "Complex Moment Diagram" astronomical instrument to measure the height of the North Pole nationwide. He used the data calculated by field measurement to overturn the inaccurate conclusion that "Wang Ji is a thousand miles away, but his shadow is an inch".
Zhang Sui's revised Dayan Calendar is an innovative calendar, which inherits the advantages and disadvantages of ancient astronomy in China and corrects its shortcomings and deficiencies. Therefore, great achievements have been made. The most outstanding performance is to correctly grasp the speed and changing law of the sun's movement on the ecliptic. Since the Han Dynasty, astronomers of all ages have believed that the speed of the sun running on the ecliptic is uniform and constant. Zhang Sui used unequal interval quadratic interpolation method to calculate the longitude difference between every two solar terms is the same, but the time interval is different. This algorithm basically conforms to astronomical practice and is a great progress in astronomy. Moreover, Zhang Sui's "Da Yan Li" calculates the degree of the ecliptic with the cubic difference of interpolation method, and also puts forward the scientific conclusion that the ecliptic will not return to its original place once a month, but will return once more than its original place. Dayan Calendar had a great influence on astronomy in China. Until the end of Ming Dynasty, historians adopted this calculation method and achieved good results.
Li Daoyuan loved the mountains and rivers of the motherland since childhood and was very interested in the study of geography. He read many ancient geography works, such as Shan Hai Jing, Yu Gong, Yu Benji, Li Zhouzhi, Geography of Han Dynasty, Water Mirror and so on. And feel that the contents recorded in these geographical works are not thorough and complete enough. He compared the geographical phenomena he saw with ancient geographical works and found that geographical phenomena changed and developed with the passage of time. In ancient times, the situation was very bleak, because the migration of tribes, the decline and fall of cities, the changes of rivers and the different names were all very complicated. If the geographical phenomena of these changes are not recorded in time, future generations will not be able to understand the geographical changes in history. To this end, he decided to take the water mirror as the blueprint and make an annotation for it. Around the first year of Xiaochang, 40 volumes of Water Mirror Notes were completed. In order to write Notes on Water Classics, Li Daoyuan made full use of the opportunity of serving as an official in various places, conducted on-the-spot investigations, investigated local geographical history and obtained first-hand information. Wherever you go, you must visit the ditch and cross the mountains and rivers. At the same time, collect local chronicles and read widely. Due to Li Daoyuan's full preparation, the contents of the note are extremely rich. Taking waterway as the key link, this paper describes in detail the ancient and modern history, geography, economy, politics, culture, social customs and historical sites of the area where the river flows, so as to achieve the purpose of "proving the land with water, that is, preserving the ancient land". In this way, Water Mirror Notes greatly surpassed Water Mirror in content and word count, and the number of rivers increased from 137 to 1252, with more than 20 times as many words as Water Mirror, reaching more than 300,000 words, making it an unprecedented geographical masterpiece at that time. Its achievements in geography mainly include the following four items.