LECTURE IV.

Chromatic Phenomena produced by Crystals in Polarized Light
The Nicol Prism
Polarizer and Analyzer
Action of Thick and Thin Plates of Selenite
Colours dependent on Thickness
Resolution of Polarized Beam into two others by the Selenite
One of them more retarded than the other
Recompounding of the two Systems of Waves by the Analyzer
Interference thus rendered possible
Consequent Production of Colours
Action of Bodies mechanically strained or pressed
Action of Sonorous Vibrations
Action of Glass strained or pressed by Heat
Circular Polarization
Chromatic Phenomena produced by Quartz
The Magnetization of Light
Rings surrounding the Axes of Crystals
Biaxal and Uniaxal Crystals
Grasp of the Undulatory Theory
The Colour and Polarization of Sky-light
Generation of Artificial Skies.


LECTURE V.

Range of Vision not commensurate with Range of Radiation
The Ultra-violet Rays