This slender book opens a path through Maxwell’s massive Treatise on Electricity and Magnetism that attains two important objectives: first, in Maxwell’s own words and mathematics, it presents an overview of the revolutionary field theory of electricity and magnetism, from the most basic phenomena to the complete theory; and second, it shows, using additional original papers by Maxwell, how the four Maxwellian equations familiar to later physicists emerge from the more discursive general theory. The final part of the path, leading from the Treatise to the equations, passes, surprisingly and delightfully, through Maxwell’s presentation of the wave theory of light as a direct consequence of electromagnetic field theory. Maxwell’s numerous clear physical examples and illustrations, and Howard Fisher’s lucid explanatory notes, allow even those without a knowledge of calculus to understand the general features of electromagnetic theory, as Maxwell himself developed it.