1. The Origin of the Electromagnetic Theory.The electromagnetic theory of light, now for many years in universal acceptance, was proposed and developed by James Clerk Maxwell about the year 1865* By elimination, from his classical differential equations, of the electric current Maxwell has obtained, for the " vector potential" 51,+ a differential equation of the second order which in the case of a non-conducting isotropic medium has assumed the form*/*^=v% .... [M]where v2 is the Laplacian (Maxwell's - v*» borrowed from Hamilton's calculus of quaternions). Maxwell's coefficients, the " specific inductive capacity " K, and the magnetic " permeability " ft, are not pure numbers. Let c be the ratio of the electromagnetic unit of electric charge to the electrostatic unit of charge. Then Maxwell's coefficients are such that, for air (or vacuum),K = 1, /* ="-5, in the electrostatic system, K = ft, = 1, in the electromagnetic system.G* Phil, Tram., 18G5, p. 150 et saTable of Contents CONTENTS; page; 1 The Origin of the Electromagnetic Theory 1; 2 Advantages of the Electromagnetic over the Elastic; Theory of Light 5; 3 Maxwell's Equations Plane Waves 16; 4 Reflection and Refraction at the Boundary of Isotropic; Media; E in Plane of Incidence 22; 5 Reflection and Refraction ; E _L Plane of Incidence Note; on the Transition Layer 28; 6 Total Reflection 31; 7 Optics of Crystalline Media : General Formula and; Theorems 35; 8 The Properties of the Electrical Axes of a Crystal 41 i, Optical Axes 43; 10 Uniaxial Crystals 45; Index r* 47; viiAbout the Publisher Forgotten Books is a publisher of historical writings, such as: Philosophy, Classics, Science, Religion, History, Folklore and Mythology.Forgotten Books' Classic Reprint Series utilizes the latest technology to regenerate facsimil