The fourth volume of Continuum Physics is devoted to the exposition of field theories for bodies which possess inner structure that can interact with
mechanical and electromagnetic fields. The purpose here is a thorough and
precise presentation of exact continuum theories on materially nonuniform
or nonsimple bodies (bodies composed of single, dipolar, and deformable
elements) that can respond to short- and long-range interparticle loads and
fields. Most of these theories have acquired their present definitive forms dur-
ing the last decade or so, even though basic ideas and certain limited or
approximate developments on some of these theories can be traced back to
the turn of the century. With the explosive developments that have taken
place during the last decade. continuum physics is now very rich, and the
impossible dream of bridging the gap between classical phenomenological
physics and atomic and molecular physics is in sight.