A paper by David Brewster is read to the Royal Society, belatedly announcing his discovery of what we now call the biaxial class of doubly-refracting crystals. On the same day, Augustin-Jean Fresnel signs a "supplement" (submitted four days later) on reflection of polarized light.

Sir David Brewster was a British scientist, inventor, author, and academic administrator. In science he is principally remembered for his experimental work in physical optics, mostly concerned with the study of the polarization of light and including the discovery of Brewster's angle. He studied…