When did China's compass come into use?

The invention and use of the compass was in the Warring States period. The earliest compass was actually Sina in ancient China. During the Spring and Autumn Period, working people in China discovered a kind of stone that can absorb iron during mining and smelting. This stone is a magnet. During the Warring States period, some people used magnets to make instruments to determine the direction. This is the earliest compass-Sina.

Compasses are often used in navigation, geodesy, travel and military affairs. The invention of the compass with physical direction indication has three parts, namely Sina, compass and magnetic needle, all of which belong to the invention of China. According to ancient mine records, it first appeared in the Cishan area during the Warring States Period.

Compass is the result of China ancient working people's understanding of magnet magnetism in long-term practice. As one of four great inventions of ancient china, its invention has played an inestimable role in the development of human science, technology and civilization. In ancient China, the compass was first used for rituals, etiquette, military affairs and divination, and to determine the orientation when looking at geomantic omen.

How to use a compass

1. When using the compass, we need to stay away from things that can produce magnets, such as cars, barbed wire, high-voltage lines, etc., and it is best to keep the distance above 10 meter, otherwise the accuracy of the compass results will be affected. In addition, the compass should be placed horizontally, otherwise it is easy to cause errors in the compass results.

When the compass is placed horizontally, the pointer will stop swinging, so that we can see the north-south direction accurately. If the compass can't accurately judge the north-south direction, it may be that the magnetic field interferes with the compass.