Description
The Compass, called Sinan in an ancient times, the main component is a magnetic needle mounted in the shaft. The magnetic needle can rotate freely under the action of the natural geomagnetic field and keep in the tangential direction of the magnetic meridian. The north pole of the magnetic needle points to the geographical south pole. A performance can discern the direction. The compass is the result of the ancient Chinese working people's understanding a magnetism in long-term practice. As one of the four great inventions in ancient China, it's invention played an inestimable role in development of human science, technology and civilization. In ancient China, the guide was first used in ritual, ceremonial, military, and divination and feng shui to determine orientation.