This book is an in depth study of early photomechanical processes to the beginning of the Twentieth Century. 159 processes and printers are identified with 114 of them being illustrated. Most of the processes have a detailed explanation of the methods used. There are a total of over 650 illustrations in color with photomicrographs to show the multiplicity of printing patterns. The author has been a student of the history of these methods for over 40 years.