Who invented Si Nan?

Sinan’s invention is the result of the long-term understanding of the magnetism of objects by the working people of ancient China. The specific inventor cannot be verified due to the long history.

According to the "Ancient Mine Records", Sinan first appeared in the Cishan area of ??Hebei Province during the Warring States Period. According to modern archaeologists' speculation, a spoon-shaped object was carved out of natural magnetite and placed on a smooth plate with directions engraved on it. The direction could be identified using the function of a magnet guide. The only physical object found so far is in Chengdu, Sichuan. It is the ancestor of the compass used today.

The south pole (S pole) of the magnet is ground into a long handle, placed on a smooth mirror-like base made of bronze, and then cast with directional engravings. When the magnetic spoon stops rotating on the chassis, the handle of the spoon points in the direction of true south, and the mouth of the spoon points in the direction of true north. This is traditionally considered to be the world's earliest magnetic guide instrument, called Sinan. Among them, "Si" means "finger".

Extended information:

Sinan's shortcomings:

The emergence of Sinan is a practical application of people's understanding of the polarity of magnets. However, Sinan also has many shortcomings. Natural magnets are difficult to find and are prone to loss of magnetism due to impact and heat during processing.

So the magnetism of Sinan is relatively weak, and the contact point between it and the ground must be very smooth, otherwise it will be difficult to rotate due to excessive rotational frictional resistance, and the expected guiding effect cannot be achieved. Moreover, Sinan has a certain size and weight and is very inconvenient to carry. This is the main reason why Sinan has not been widely used for a long time.

Baidu Encyclopedia - Sinan (ancient Chinese identification instrument)

People's Daily Online - Magnet From Sinan to Super Energy Storage King