For several years Pasteur revolved all the possibilities in Mitscherlich's observations and, finally, came to the conclusion that there perhaps existed in the paratartrates, as prepared by Mitscherlich, two different groups of crystals, the members of one of which turned the plane of polarization to the right, the other to the left.
"Makers of Modern Medicine"
James J. Walsh
All these latter substances turn the plane of polarization.
"Makers of Modern Medicine"
James J. Walsh
He studied the questions of interference and polarization, and determined the approximate velocity of light.
"A Budget of Paradoxes, Volume II (of II)"
Augustus de Morgan