  In December 1907, Minkowski expressed the Maxwell equations in the very
beautiful and compact 4-dimensional form: lor f=-s, lor F^*=0. Here `lor', an
abbreviation of Lorentz, represents the 4-dimensional differential operator. We
study Minkowski's derivation and show how these equations generalize to their
modern premetric form in the framework of tensor and exterior calculus (valid
also in general relativity). After mentioning some applications of premetric
electrodynamics, we turn to Minkowski's discovery of the energy-momentum tensor
of the electromagnetic field. We discuss how he arrived at it and how its
premetric formulation looks like.
