Originally published in 1955, this textbook on electron optics was aimed both at scientists already engaged in research as well as scientists new to this field of study. The book has a threefold purpose: firstly, 'to relate the theory of electron-optical instruments and particle accelerators to classical optics and dynamics'; secondly, 'to set out general procedures which may be applied to the study of image-formation in electron-optical instruments and stability in particle accelerators'; thirdly, 'to apply these procedures to the analysis of the properties of the more important instruments and machines'. Chapters are detailed and range from 'The variational equation' to 'Uniform focusing in particle accelerators'. Diagrams are included for reference. This book will be of great value to scholars of the history of physics and electromagnetics.