CONTENTS.
[CHAPTER I.]
Sources of Light—Reflected Light—Reflection from Roughened Surfaces—Colour Constants p. 11
[CHAPTER II.]
A Standard of Light—Formation of the Spectrum by Prisms and by the Diffraction Grating—Wave-lengths of the principal Fraunhofer Line—Position of Colours in the Spectrum p. 17
[CHAPTER III.]
The Visible and Invisible Parts of the Spectrum—Methods for showing the Existence of the Invisible Portions—Phosphorescence—Photography of the Dark Rays—Thermo-Electric Currents p. 30
[CHAPTER IV.]
Description of Colour Patch Apparatus—Rotating Sectors—Method of making a Scale for the Spectrum p. 41