"A Dynamical Theory of the Electromagnetic Field", published in 1865, is the third of James Clerk Maxwell's papers on electromagnetism, and the paper in which the original set of four Maxwell's equations first appeared.

Maxwell's classic is organized as follows:

Part I. Introductory
Part II. On Electromagnetic Induction
Part III. General Equations of the Electromagnetic Field
Part IV. Mechanical Actions in the Field
Part V. Theory of Condensers
Part VI. Electromagnetic Theory of Light
Part VII. Calculation of the Coefficients of Electromagnetic Induction

(Note: this is an exact facsimile of the original paper, in order to preserve the equations. It may be difficult to read on a small device.)