Researches in Colour Vision and the Trichromatic Theory

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. This work is divided into Part I. And Part II. Part I. Is elementary to some extent, and has been the subject of lectures to students. This part need not, of course, be studied by advanced workers, except so far as is necessary by the references made to it in Part II., where Colour Vision is the main subject. Paragraphs in square brackets may be omitted in reading.