*The group of weak automorhisms of a family of equivalence relations
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Otto H. Kegel (Albert-Ludwigs-Universität Freiburg)

A permutation of the set S is an automorphism of the equivalence relation E on S if it leaves all the equivalence classes of E invariant; it is a weak automorphism with, with respect to a family F of equivalence relations if there is a member E of F for which it is an automorphism. - If F is a directed set of equivalence relations then the set of of weak automorphisms is a group acting highly transitively on S. - If S is countable and if F consists of sufficiently "smooth" equivalence relations then the group (and F) may be - in a way - described (classified) by Steinitz numbers.