According to ancient mine records, Sina (one of four great inventions of ancient china, the predecessor of compass) first appeared in the Cishan area during the Warring States Period.

According to Guangming Daily in March 1982, Cishan (in present-day Wu 'an, Handan City, Hebei Province) is the birthplace of the compass, one of the four great inventions in China.

According to ancient mine records, Geography of Ming Dynasty said: "There is a magnetic mountain in the southwest of Wu 'an County, Cizhou, which produces magnetite. "

The Ming Yi Award also said: "There is a magnetic mountain in the southwest of Wu 'an County, Cizhou, which produces magnetite. "

"Ancient Mine Records" also records the theory of "Ming Yi Governance": Cishan, 30 miles southwest of the county seat, is a primary mine, hence the name Zhou.

Cishan, the hometown of compass.

The hometown of compass:

The things about compass recorded in ancient books and the authors of ancient books are located in Zhao Yan Cultural District centered on Guhan.

Compasses in ancient China, recorded in the classic range, were all made of natural magnets.

According to pre-Qin classics, only Wu 'an Cishan (now Wu 'an, Handan City, Hebei Province) produced natural magnets.

During the Spring and Autumn Period and the Warring States Period, it was possible to create Sina, only the Zhao Yan Cultural District centered on Handan, and Wu 'an was probably the hometown of compass.

The function and significance of compass;

Compass is a simple tool to judge the direction.

The predecessor of compass is Sina, one of the four great inventions in ancient China.

The main component is a magnetic needle that can rotate freely on the shaft. The magnetic needle can be kept in the tangential direction of magnetic meridian under the action of geomagnetic field. The north pole of the magnetic needle points to the geographical south pole, which can be used to identify the direction.

It is often used in navigation, geodesy, tourism and military affairs.

The invention of compass is the result of our working people's understanding of the magnetism of objects in long-term practice. Due to productive labor, people came into contact with magnetite and began to understand its magnetism.

People first discovered the property that magnets attract iron. Later, the directivity of magnets was discovered. After many experiments and studies, a practical compass was finally invented.