Jean Baptiste Biot
(April 21 1774
-February 3 1862
) was a French physicist
who in the early 1800s
studied the relationship between electrical current and magnetism (see Biot-Savart's Law
), as well as the polarisation of light passing through chemical solutions.
He was the first person to discover the optical difference of mica, and therefor the mineral biotite was named after him.
In 1804 he made a hot-air balloon ascent with Joseph Gay-Lussac to a height of five kilometres in an early investigation of the Earth's atmosphere.