A brief discussion on the development from Sinan to compass and then to magnetic compass.

The emergence of Sinan

Sinan is a compass device that appeared more than 2,000 years ago. At that time, craftsmen polished and carved magnetic stones into spoon-shaped objects and placed them on a smooth plate with direction marks engraved on the edge of bronze. This magnetic spoon-shaped object would slowly rotate. When it stopped rotating, the handle of the spoon-shaped object pointed to the south, and the mouth of the spoon-shaped object pointed to the north. This is the early pointing instrument in my country - Sinan.
Sinan developed into a compass

After Sinan, in order to use the device indicating direction more conveniently, people gradually made the ancient compass, the compass car, and the compass fish based on Sinan, and improved it on the basis of the compass fish, installing the magnetic needle and the dial in a small container, forming a more practical and more widely used compass in ancient times. However, due to the limitations of ancient craftsmanship, the compass at that time was to grind the natural magnet into a magnetic needle for use. Affected by the magnetic declination, the ancient compass may not be completely pointing south.
Compass developed into magnetic compass

With the continuous development of technology and science, the change of transportation, and the improvement of people's demand for pointing, people later invented the magnetic compass. The early magnetic compass was a compass that placed the magnetic needle in a liquid, which could indicate the direction better and more stably. With the advancement of technology, the magnetic compass has now developed into one of the navigation equipment for small and medium-sized ships. Large ships are also equipped with special rudder magnetic compasses, standard magnetic compasses and other navigation aids.

Not only that, there are many types of magnetic compasses at present, including desktop magnetic compasses, small boat magnetic compasses, vertical reflection magnetic compasses, etc.
This is the process of the development of Sinan to compass, and then to the emergence of magnetic compass. People's improvement of an invention is often due to demand and the desire for more convenient use. The invention and improvement of navigation instruments such as Sinan, compass, compass, magnetic compass, and magnetic compass are also the reasons for people's demand for direction positioning and more convenient use.