Zhongzhou is also very developed in science and technology, taking the Eastern Han Dynasty as an example. At the end of the Eastern Han Dynasty, eunuch Cai Lun summed up predecessors' experience in Luoyang, Kyoto, and invented papermaking, which contributed to the spread and development of Chinese culture and world culture. Another example is Zhang Heng and Zhang Zhongjing in the Eastern Han Dynasty, who were famous astronomers and medical scientists in the history of China.

(1) Great astronomer Zhang Heng and his hometown Nanyang. Zhang Heng was born in Xi, Nanyang County (now Nanyang County, Henan Province) in the Eastern Han Dynasty. Zhang Heng was born in a noble family in Nanyang. Grandfather Zhang Kan was the prefect of Shu County. Zhang Heng has shown a talent for cleverness since he was a teenager. When he was young, he went to Luoyang, the capital city, and entered imperial academy. Although he is superior, he is calm and calm.

Zhang Heng especially likes astronomy, calendars, arithmetic and so on. When Emperor An of the Eastern Han Dynasty heard that Zhang Heng was good at arithmetic, he sent a rickshaw to take Zhang Heng to Beijing, appointed him as a doctor, and was promoted to Taishiling. During this period, Zhang Heng carefully studied the calendar and astronomical phenomena, created the world's earliest armillary sphere rotated by water power, and wrote mathematical works such as "Theory of Calculation Outline" and "Calculation through Network". In the first year of Yang Jia's reign (132), Zhang Heng also invented the Hou Feng seismograph, which was the first instrument in the world to determine the orientation of earthquakes. The seismograph is made of high quality copper with a diameter of 8 feet. It is covered and raised, and looks like a wine statue. The face is cast with the shapes of seal, mountain, turtle, bird and beast. There are eight dragons on the watch, and the taps are in all directions. Longkou is holding a copper pill, and there is a toad below, ready to take it. All kinds of organs are respected, and the organs are connected with Longkou. If there is an earthquake anywhere, the dragon facing the earthquake will spit out copper balls and fall into the toad's mouth, and the vibration will become louder and louder, reporting the direction of the earthquake to people. Although Yi Long started the engine, none of the other seven dragons moved. On one occasion, scholars in Beijing blamed the dragon engine facing west for not moving. A few days later, the postman came to report that there was an earthquake in Longxi. "Everyone was amazed." Since then, historians have observed seismographs recording earthquakes.

Zhang Heng also drew the first relatively complete star map of China, and made a compass car and an automatic memory drum car, which made great contributions to the development of science and technology in China and the world. Zhang Heng is also a writer and painter, and his works Erjing Fu, Sixuan Fu and Dunan Fu all have high literary value. In memory of Zhang Heng, the world scientific organization once named craters on the moon and planets in the universe after him.

Xia Village, Nanyang County, Henan Province, is Zhang Heng's hometown, with "the former site of Ping Zi" and Zhang Heng Memorial Hall. Zhang Heng's Tomb is in Little Shi Qiaocun, Nanyang County. The tomb is eight meters high and 79 meters in circumference, surrounded by octagonal flower walls. The great scientist Zhang Heng is buried here.

(2) Zhang Zhongjing and his hometown Nanyang. Zhang Zhongjing was born in Nanyang County (now Nanyang City, Henan Province) in the Eastern Han Dynasty. Since he was a teenager, he has been extremely smart, diligent in learning and good at thinking. Zeng studied under Zhang Bozu, a famous doctor in the same county. When Emperor Ling of the Eastern Han Dynasty, Zhang Zhongjing once "raised filial piety as the magistrate of Changsha", but at the end of the Eastern Han Dynasty, eunuchs were authoritarian, the court was fatuous, the officialdom was dark, and the people were in poverty. With the popularity of typhoid fever among the people, many people died, so he gave up his official position and retired to study medicine. Zhang Zhongjing extensively collected prescriptions, summed up the experience of the previous generation, and practiced medicine among the people. There are sixteen volumes of Treatise on Febrile Diseases (two editions of Treatise on Febrile Diseases and synopsis of the Golden Chamber adapted by Wang Shuhe, a famous doctor in Jin Dynasty), which summarize eight categories of TCM diagnosis, including yin and yang, exterior and interior, deficiency and excess, cold and heat, and the treatment methods such as sweating, vomiting, diarrhea, warming, Taoism and harmony.

The diagnosis and treatment method summarized by Zhang Zhongjing has become the criterion of TCM practice in later generations and made great contributions to the development of TCM. Zhang Zhongjing was called "medical sage" by later Chinese medicine.

Shortly after Zhang Zhongjing's death, people established a "medical shrine" in his hometown to commemorate this medical scientist who made great contributions to human health and Chinese medicine. The "medical shrine" is an ancient cemetery on the bank of Wenliang River in the eastern suburb of Nanyang City, which is divided into two parts. After entering the gate, there is a tower-shaped pavilion on both sides, which is 13 meters high and decorated with rosefinch paintings. Inside the gate, there is a stone screen door, with a biography of Zhang Zhongjing engraved on the front and a preface to Treatise on Febrile Diseases engraved on the back. The gallery in the courtyard is inlaid with a group of stone carvings of Zhang Zhongjing's life and 1 17 stone statues of ancient famous doctors in China.

Behind the stele gallery is the tomb of Mr. Zhang Zhongjing, the medical sage of Changsha Prefecture. Fiona Fang of Zhongjing Tomb is 33 meters long. Above it is a tomb pavilion with cornices and flowing corners, and behind it is a temple, a main hall and an east-west hall. There is a statue of Zhang Zhongjing in the main hall. The temple has the original woodcut edition of Treatise on Febrile Diseases and more than 10,000 volumes about Zhang Zhongjing's medical history, which was collected by Zhang Shaozu, the forty-sixth generation grandson of Zhang Zhongjing, during the Tongzhi period of the Qing Dynasty.

Zhang Zhongjing was a great Chinese doctor in the Eastern Han Dynasty. He first treated diseases with various Chinese medicines, and was called the originator of the cube. His Treatise on Febrile Diseases is regarded as a medical classic by later generations. Zhang Zhongjing became the founder of traditional medicine in China, and was called "the sage of medicine". At present, there is "Zhang Zhongjing Medical University" in Nanyang City, Henan Province. 1982, Chinese and foreign medical professionals held a seminar on Zhang Zhongjing's medical thoughts to study and commemorate this great Chinese medicine practitioner.