= History of polarization
Good overgrown section in the middle of <Fresnel>'s biography: https://en.wikipedia.org/w/index.php?title=Augustin-Jean_Fresnel&oldid=1064236740\#Historical_context:_From_Newton_to_Biot[].
Particularly cool is to see how <Fresnel> fully understood that light is somehow polarized, even though he did not know <electromagnetic theory of light>[that it was made out of electromagnetism], clear indication of which only came with the <Faraday effect> in 1845.
https://spie.org/publications/fg05_p03_maluss_law[]:
\Q[At the beginning of the nineteenth century the only known way to generate polarized light was with a calcite crystal. In 1808, using a calcite crystal, Malus discovered that natural incident light became polarized when it was reflected by a glass surface, and that the light reflected close to an angle of incidence of 57° could be extinguished when viewed through the crystal. He then proposed that natural light consisted of the s- and p-polarizations, which were perpendicular to each other.]