Pierre Curie built a sensitive torsion balance to measure
the magnetization of paramagnetic bodies.
The torsion balance was invented by John Michell
and used by Henry Cavendish to measure the density of the earth,
and by Charles-Augustin de Coulomb to derive the inverse-square law.
Pierre Curie also showed that above a certain transition point,
known as the Currie temperature,
a ferromagnet loses its intrinsic magnetization.
Above that temperature, however,
it still responds as a paramagnet to an external magnetic field.
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