On the invention and creation in han dynasty.

Agriculture, handicrafts and commerce in China developed rapidly in Han Dynasty, and the first peak of social and economic development appeared in the initial development period of feudal society. There are six main reasons for this. First, China's feudal unification was formed in the Han Dynasty, with social stability and political clarity, which provided a good social environment for social and economic development. Second, the rulers in the early Han Dynasty learned the lessons from the death of Qin Dynasty, implemented the policy of recuperation and encouraged the development of production. Third, the Han Dynasty attached importance to the development of water conservancy, and formed a nationwide irrigation network, with obvious characteristics of farmland water conservancy areas. Fourth, reforming production tools and popularizing advanced production technology are conducive to the development of agriculture. Fifth, the progress of science and technology in Han Dynasty created important conditions for social and economic development. Sixth, the communication and contact between the Han nationality in the Central Plains and the people of all ethnic groups in the border areas are getting closer and closer, which has promoted the economic and cultural exchanges between ethnic groups and regions.

So, what are the typical inventions in the Han Dynasty?

First, mathematics.

When it comes to mathematics in the Han Dynasty, I have to mention Zhou Pian and Nine Chapters of Arithmetic. Zhou Bi Su 'an Jing, formerly known as Zhou Bi Su 'an Jing, is one of the ten books of Calculation Jing. It is the oldest work on astronomy and mathematics in China, which was written in 1 century BC, mainly explaining the theory of covering the sky and the method of four seasons calendar at that time. In the early Tang Dynasty, it was stipulated as one of imperial academy's teaching materials, so it was renamed Zhou Kuai.

The main achievement of Zhou pian Shu Jing in mathematics is the introduction of Pythagorean theorem, which records a dialogue between Shang Gao and Zhou Gong. Shang Gao said: "... so fold the moment, tick three, fix four, and cross the corner five." Meaning: When two right-angled sides of a right-angled triangle are 3 (hook) and 4 (chord) respectively, the radius angle (chord) is 5. In the future, people will simply say that this fact is "three strands, four chords and five". According to this allusion, Pythagorean theorem is called quotient height theorem.

Nine Chapters Arithmetic is a mathematical monograph written by Zhang Cang and Geng Shouchang in ancient China. It is the most important of the ten calculation classics, written in the first century A.D. Nine Chapters of Arithmetic is very rich in content, summarizing the mathematical achievements in the Warring States, Qin and Han Dynasties. At the same time, Nine Chapters Arithmetic has its unique achievements in mathematics. It not only mentioned the problem of score at the earliest, but also recorded the problem of surplus and deficiency at the earliest. It is a comprehensive historical work and the most concise and effective applied mathematics in the world at that time. Its appearance marks the formation of a complete system of ancient mathematics in China.

Second, the astronomical calendar

The achievements of astronomical calendar in Han Dynasty are quite good. During the period of Emperor Wu of the Han Dynasty, astronomers formulated China's first complete almanac, taichu calendar, and began to take the first month as the beginning of the year. In the exploration of space, the sunspot record in the Western Han Dynasty is recognized as the earliest sunspot record in the world, which is very valuable, because it was not until modern times that Galileo observed sunspots with telescopes, and our ancestors knew about the existence of sunspots without any telescopes at all.

Zhang Heng made the earliest scientific explanation for the solar eclipse in the Eastern Han Dynasty. He also invented the seismograph with eight directions. There is a dragon with copper beads in every direction, and there is a toad under each dragon. If there is an earthquake on both sides, the copper beads of Longkou in that direction will fall into the toad's mouth, so that the earthquake direction thousands of miles away can be detected, which is 1700 earlier than that in Europe.

In addition, Zhang Heng also inherited the achievements of Langzhong people in the Western Han Dynasty and invented the armillary sphere to demonstrate the "armillary sphere" of celestial bodies.

Third, medicine.

When it comes to medicine in the Han Dynasty, we have to mention Huangdi Neijing, which is an early and important medical document in China. The appearance of Huangdi Neijing laid the foundation of Chinese medicine theory. In addition, among the famous medical works in the Han Dynasty, Shennong's Herbal Classic, the first complete pharmacological work in China, and Zhang Zhongjing's masterpiece Treatise on Febrile Diseases and Miscellaneous Diseases were compiled in the Eastern Han Dynasty.

Among medical scientists, two doctors are famous all over the world. One was Hua Tuo, a famous doctor in the Eastern Han Dynasty, who was good at surgery and invented Mafengsan more than 600 years earlier than the West. The other is Zhang Zhongjing, a famous doctor in the Eastern Han Dynasty, known as the "medical sage".

Fourth, handicrafts.

Paper-making, the ancestor of paper, began to use silk floss and hemp in the Western Han Dynasty, while Cai Lun improved paper-making in the Eastern Han Dynasty and formed paper in the modern sense. Papermaking has become one of the four great inventions in China. To some extent, with paper, there is human civilization.

Jacquard is widely used in silk weaving industry, which can weave exquisite patterns and has high dyeing technology.

In the iron smelting industry, Du Shi, the magistrate of Nanyang in the Eastern Han Dynasty, invented the water drain (iron treatment tool) for blast ironmaking, which saved manpower and improved smelting quality. It was more than 1000 years earlier than Europe, which also made iron weapons replace bronze weapons in Han Dynasty. The technology of casting money is mature, such as three baht and five baht.

The Han Dynasty was also the first time that China invented porcelain firing. During this period, distillation, hydraulic mill, the prototype of modern horse yoke and abdominal belt, lacquerware, reciprocating piston bellows for metallurgy, etc. Also invented. The painting techniques in this period are unique, such as the silk paintings unearthed in Mawangdui, and all kinds of daily necessities are complete, such as the bronze mirror known as the "magic mirror of Han Dynasty".

By the Han Dynasty, the technology of cooking salt was also constantly improved, and distilled liquor appeared, and the brewing level was also perfect.

Waterproof compartments, multiple masts and stern rudders were adopted in the shipbuilding industry in Han dynasty, and compasses began to be used.

Verb (abbreviation of verb) agriculture

Promote cattle self-breeding and field substitution. According to Records of Hanshu Shihuozhi, at the end of Emperor Wu of the Han Dynasty, Zhao was chosen as the captain to search for Li, and A Compendium of Tong Jian recorded his method. Substitution method is also an ancient farming system improved and popularized by Zhao State-rotation system.

In the Western Han Dynasty, there were also plowing fields (turning over and breaking up the soil), plowing fields (sowing tools) and two cows carrying poles. New irrigation tools such as water rafts appeared in the early Eastern Han Dynasty, and unicycles, waterwheels and suspension bridges appeared in the late Han Dynasty.

I am a civilized person, and my country is boundless!