The way you visually match color today is the result of Albert H. Munsell’s work nearly a century ago. In fact, modern day color theory and mathematical color system is based on Munsell’s theory of color. Learn more about Munsell’s groundbreaking work in his A Color Notation featuring a preface by his son, A.E.O. Munsell and an introduction by Royal B. Farnum, former director, Rhode Island School of Design (RISDI). This book is in the public domain and can be viewed here: A Color Notation by Albert Munsell.