CONTENTS.

PAGE
Preface vii
CHAPTER I.
The Eye [1]
CHAPTER II.
Simple Colours and their Mixture [15]
CHAPTER III.
Three Colour Sensations Possible [32]
CHAPTER IV.
The Young and Hering Theories of Colour Vision [41]
CHAPTER V.
General Aspect of Colour Blindness [58]
CHAPTER VI.
Colour Blindness exhibited by Colour Discs and exhibited by Luminosity Curves of the Spectrum [74]
CHAPTER VII.
Luminosity of Colours to Different Parts of the Retina [88]
CHAPTER VIII.
Luminosity of a Feeble Spectrum and the Limit of the Perception of Colour [98]
CHAPTER IX.
The Extinction of Light from the Spectrum [108]
CHAPTER X.
The Extinction of the Perception of Light by the Colour Blind [122]
CHAPTER XI.
Tobacco Blindness [137]
CHAPTER XII.
Examples of Colour Blindness due to Disease [148]
CHAPTER XIII.
The Holmgren Test for Colour Blindness [167]
CHAPTER XIV.
The Spectrum Test for Colour Blindness [180]
CHAPTER XV.
The Young and Hering Theories of Colour Vision Compared [187]
Appendix [201]
Index [229]