  This paper is mostly a collection of ideas already published by various
authors, some of them even a long time ago. Its intention is to bring the
reader to know some rather unknown papers of different fields that merit
interest and to show some relations between them the author claims to have
observed. In the first section, some comments on old unresolved problems in
theoretical physics are collected. In the following, I shall explain what
relation exists between Feynman graphs and the teleparallel theory of Einstein
and Cartan in the late 1920s, and the relation of both to the theories of the
incompressible aether around 1840. Reviewing these developments, we will have a
look at the continuum theory of dislocations developed by Kroener in the 1950s
and some techniques of differential geometry and topology relevant for a modern
description of defects in continous media. I will then illustrate some basic
concepts of nonlinear continuum mechanics and discuss applications to the above
theories. By doing so, I hope to attract attention to the possible relevance of
these facts for `fundamental' physics.
