ABSTRACT
A number of crystals, pure liquids and solutions exhibit the properties: when a parallel beam of linearly polarized monochromatic light traverses these media the direction of vibration of the incident light is rotated through an angle in the plane of the wave. The angle is proportional to the thickness traversed. The rotation of the plate in its own plane, or the interchange of the two faces of the plate do not bring about any modification. A parallel beam of linearly polarized light illuminates a concentrated solution of sugar contained in a vertical tube which contains a slight precipitate of Ag2CO3. In monochromatic light, bright and dark regions are observed along the length of the tube. Transparent isotropic substances placed in a uniform field of magnetic induction show rotatory polarization for the light beams propagating parallel to the field.
