1 Introduction.- 1.1 Physical Aspects of Field Dynamics.- 1.2 The Mathematical Formalism.- 1.3 Maxwell's and Einstein's Equations.- 2 The Electromagnetic Field of a Known Charge Distribution.- 2.1 The Stationary-Action Principle and Conservation Theorems.- 2.2 The General Solution.- 2.3 The Field of a Point Charge.- 2.4 Radiative Reaction.- 3 The Field in the Presence of Conductors.- 3.1 The Superconductor.- 3.2 The Half-Space, the Wave-Guide, and the Resonant Cavity.- 3.3 Diffraction at a Wedge.- 3.4 Diffraction at a Cylinder.- 4 Gravitation.- 4.1 Covariant Differentiation and the Curvature of Space.- 4.2 Gauge Theories and Gravitation.- 4.3 Maximally Symmetric Spaces.- 4.4 Spaces with Maximally Symmetric Submanifolds.- 4.5 The Life and Death of Stars.- 4.6 The Existence of Singularities.