What is the main achievement of Meng Qian's pen talk (please, get it quickly)

, "Meng Qian's pen talk"-the coordinates in the history of science in China.

Meng Qian Bi Tan was written by Shen Kuo in the Northern Song Dynasty, and was praised as "the coordinate in the history of science in China" by Dr Joseph Needham, a British scholar.

Meng Qian Bi Tan is a comprehensive scientific masterpiece written in the genre of notes, with a total of 30 volumes, involving mathematics, astronomy, calendar, meteorology, geology, geography, physics, chemistry, metallurgy, water conservancy, architecture, biology, medicine, pharmacology and many other fields. Among them, there are precious and faithful records of scientific and technological achievements at that time, as well as the author's insights through concentrated practice and in-depth research.

In terms of calendar, Meng Qian Bitan put forward the "Twelve Qi Calendars". According to the solar terms, the big month is 3 1 day, the small month is 30 days, and there is no leap month. This calendar, which completely unifies the four seasons and 24 solar terms and 12 months, is especially suitable for agricultural production.

In geology, Meng Qian Bitan recorded the nature and use of the earliest oil in the world, and used the name of "oil" for the first time. Shen Kuo thought that "oil is born in the ground at most" and predicted that "this thing will be popular in the world".

In physics, Meng Xi Bitan first put forward the theory of magnetic declination in the world. Shen Kuo believes that the compass "can guide, but it is often slightly to the east, not completely to the south". The book also discusses the "echo" phenomenon, that is, the * * vibration in acoustics; The principles of pinhole imaging and concave-convex mirror are also explained scientifically.

Geographically, Meng Xi Bitan pointed out that the dangerous landform of Yandang Mountain is "a huge valley with huge cliffs, unlike other mountains", which is the result of running water scouring. The book also correctly explains that the North China Plain is formed by the sediment contained in turbid streams such as the Yellow River, Zhanghe River, Hutuo River, Zhuoshuixi River and Sanggan River.

The advantage of Meng Qian Bi Tan is that it describes the inventions and creations of many working people. Such as Buyi Bi Sheng's movable type printing; Wood sutra written by carpenter Yu Hao; Three-stage construction method of skillfully plugging the mouth by river managers; Cizhou (now Cixian County, Hebei Province) steelmaking, Huainan re-brake, Suzhou-Kunshan shallow water embankment construction method and so on.

Meng Qian Bi Tan comprehensively reflects the scientific and technological level in ancient China, especially in the Northern Song Dynasty. It is a very important masterpiece in the history of science and technology in China and occupies a place in the history of science and technology in the world.