On Physical Lines of Force

James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish scientist in the field of mathematical physics. His most notable achievement was to formulate the classical theory of electromagnetic radiation, magnetism, bringing together for the first time electricity and light as manifestations of the same phenomenon. He was a member of the Royal society of London.
In this book, the author derived the equations of electromagnetism in conjunction with a "sea" of "molecular vortices" which he used to model Faraday's lines of force. He made a parallel between the density of this medium and the magnetic permeability, as well as an analogy between the transverse elasticity and the dielectric constant. Read the book to know more about it!