Zhang Heng’s seismograph was removed from the history textbook. Academician of the Chinese Academy of Sciences: Hanging pieces of meat on the beams of the house are better than this

Zhang Heng is a famous scientist, writer, mathematician and astronomer in the Eastern Han Dynasty. His research and monographs span many fields, and he is respected by the world as the "sage of science". In 94 AD, the 17-year-old Zhang Heng was well-known in the local area by reading a wide range of books and outstanding talents. Many local officials wanted to promote Zhang Heng as "filial piety", but they were all rejected one by one.

In Zhang Heng's view, it is not his life pursuit whether to stay in his hometown and continue to read the scriptures, explore knowledge, or step into an official career, get promoted and make a fortune. He wants to verify the reliability of knowledge through practice, test the uniqueness of truth, and explore more unknown scientific fields. During the study tour where Zhang Heng sought teachers and friends, he witnessed countless palace ruins and mountains and rivers.

personally experienced the local customs and product culture of the Guanzhong generation, and also had a richer understanding of the merchants, wealthy people, and people in the suburbs of Changan . The following year, the 18-year-old Zhang Heng visited the lively and bustling Luoyang , and he made friends with many aspiring young people who learned rich and five-cars and possessed special skills. For example, Cui Yuan, who is smart, studious, and proficient in astronomy and almanac; Wang Fu, who is sharp in writing, has a clear point of view, and is knowledgeable, and has written dozens of policy theories.

Zhang Heng learned a lot about astronomy, legislation, mathematics, and literature from these mentors and friends, laying a solid foundation for his future research in the field of science and technology as well as invention and creation. During the study tour, Zhang Heng did not forget to learn knowledge from ancient books. He learned about the prehistoric universe from the "Tai Xuan Jing" and developed a strong desire to explore the vast universe.

In this way, Zhang Heng read a group of books to enrich the basic knowledge, while personally observing, practicing and summing up experience, inventing many scientific instruments that benefit all mankind. among them,The story of Zhang Heng's invention of the seismograph has also been included in middle school history textbooks to encourage young people to actively explore the world of science. However, the seismograph has now been removed from the history textbook.

Academician of the Chinese Academy of Sciences Fu Chengyi pointed out sharply: "Using Zhang Heng's seismograph to detect earthquakes is better than hanging a piece of meat on a beam!" Why?

Zhang Heng invented the seismograph

Hou Feng Seismograph is the world's first earthquake detection instrument, and it is also one of the ancient great scientific and technological inventions. During the Eastern Han Dynasty, earthquakes occurred frequently in my country. The earliest earthquake recorded in the "Historical Records" was in 780 BC. The earthquake directly blocked three river channels and plundered the lives of hundreds of people. In order to predict earthquakes in time, we will effectively protect the safety and property of the people.

Since 126 AD, Zhang Heng, a Taishiling, has been collecting information and information on earthquakes across the country. After six years of experimentation and research, Zhang Heng invented the first instrument in the history of human civilization to detect the azimuth of earthquakes, the wind seismograph , which was more than 1,700 years earlier than Europe.

The appearance of the seismograph is recorded in detail in the Book of the Later Han Dynasty·Zhang Heng Biography, which provides textual evidence for the existence of the seismograph. The seismograph is made of a wellbore and looks like an ordinary wine bottle with a diameter of about eight feet. The seismograph is engraved with small seals and birds and beasts on the outside, and inside there is a pillar that connects eight directions and can trigger the switch.

The instrument is also inlaid with eight dragons with copper balls, and the base corresponds to eight toads with wide mouths. If the seismograph feels a shock, the copper ball in the dragon's mouth will fall and be caught by the toad below. At the same time, the seismograph will also emit a sound to remind technicians that an earthquake is coming, and people can judge the location of the earthquake based on the position of the dragon.

According to historical records, Zhang Heng's seismograph is more sensitive and accurate. In 138 AD, a major earthquake occurred in Shaanxi. At the same time, the dragon on the seismograph in Luoyang happened to protrude from the copper pill, and the position of the dragon was To the northwest where Shaanxi is located. After this incident, the people were convinced of the Hou Feng Geodynamic Device, and they all praised the magic and exquisiteness of this device.

Wang Zhenduo restores the Hou Feng Seismograph

With the change of times, the Hou Feng Seismograph has long been lost, and the archaeological team has not found any cultural relics related to the seismographs. In the history books. Therefore, many experts and scholars have questioned the authenticity of seismographs. In order to prove the effectiveness of the seismograph, in 1951, Wang Zhenduo, director of the Museum of Cultural Heritage Bureau, perfectly restored Zhang Heng's straight-pole seismograph model according to the ratio of 1:10.

In fact, in 1934, as a graduate student in history, Wang Zhenduo had the idea of ​​restoring seismographs. In 1936, he roughly designed the shape of the seismograph according to the description of "The Book of the Later Han Dynasty", and drew the model of the seismograph. It refers to the principle of "dangling pendulum" published by British seismologist Milne in 1883.

After the founding of New China, my country urgently needed to copy a batch of ancient artifacts to promote traditional Chinese culture. As the curator of the museum, Wang Zhenduo set out to restore the seismograph and replaced the pendant pendulum principle with the principle of the upright rod. In 1952, Wang Zhenduo's re-engraved Zhang Heng Seismograph was published on People's Pictorial, and then it was included in the history textbooks of primary and secondary schools, which became the common memory of several generations of teachers and students.

Chinese and foreign experts questioned the Zhang Heng seismograph

After the Zhang Heng seismograph was restored, it caused an uproar at home and abroad.However, while everyone is immersed in the joy of reappearing ancient objects, experts and scholars at home and abroad have raised questions about the existence and functionality of seismographs. Since 1969, seismologists in Japan, the United States, and Austria have successively published papers criticizing Zhang Heng's seismograph.

In 1972, the Japanese earthquake expert Sugeno directly proved the unreasonability of the "upright pole principle" through calculations. In 1983, experts from the United States and the two countries fundamentally denied the "upright pole principle" and believed that Wang Zhenduo's model was flawed and could not effectively predict earthquakes.

In 1984, the American academician Bolt pointedly pointed out that Wang Zhenduo's reproduced seismograph model is simple, rough in appearance, and fuzzy in working principle. The model's sensitivity to earthquakes is not even as high as human sensitivity to earthquakes. Moreover, according to It is impossible to judge the location of the earthquake from the direction of the drop of the copper pellets in Longkou.

In addition to the sharp condemnation of foreign experts and scholars, in 1976, Fu Chengyi, an academician of the Chinese Academy of Sciences, also relentlessly pointed out that "the meat under the beam is better than that!" criticism of the thesis and the monograph. The public ridicule is nothing but the most embarrassing thing is that in 1988, Nara, Japan showed this seismograph. The narrator at the time was unable to verify the sensitivity of the seismograph, and could only use a wooden stick to poke the copper bead in the dragon's mouth into the toad's mouth. Once this matter spread, the whole world began to question my country's ancient science and technology.

Although the reissue version of the seismograph has been questioned, many experts and scholars still persist in exploring the mystery of Zhang Heng's seismograph. For example, Feng Rui , a professor of the Chinese Academy of Sciences, calculated that the lowest intensity of earthquakes that occurred in Longxi during the Eastern Han Dynasty was five. At this time, the ground shaking was obvious, and even dull people and animals could sense it. This situation is completely contrary to the record in the "Hou Han Shu" that "a dragon stimulates, but the earth does not move".

If you want to achieve the effect that people do not respond and the seismograph is sensitive,The inverted stick in the instrument must be up to two meters tall and not exceed 1.5 mm in diameter. Obviously, Wang Zhenduo did not reach this point at all, so it can be confirmed that the restored seismograph cannot detect earthquakes.

Concluding remarks:

In 2004, Henan Museum and the Seismological Network Center jointly released a new subject to study Zhang Heng's model and produced a new restoration model. The subject has been awarded to experts and scholars in various fields. Recognition. However, because Wang Zhenduo's re-engraved seismograph model has received greater suspicion, the content related to Zhang Heng's seismograph has been removed from the history textbook, which is also to ensure the rigor of the textbook.

Although the seismograph has been questioned by scholars at home and abroad, we should not obliterate all Zhang Heng's contribution to the Chinese civilization. The continuous innovation and progress of China's science and technology is indispensable to the active exploration of ancient scientists. We should have the most basic respect and recognition for the research results of predecessors.