How did Gauss derive the absolute value for the field strength using his mechanical system?

Answer

By analyzing the difference in oscillation period when the magnet was magnetized versus demagnetized

Gauss analyzed the oscillation period of the suspended magnet when magnetized compared to when it was demagnetized, correlating this change with the known mechanical properties of the magnet and suspension fiber.

How did Gauss derive the absolute value for the field strength using his mechanical system?
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