  We introduce a new combinatorial principle which we call $\clubsuit_{AD}$.
This principle asserts the existence of a certain multi-ladder system with
guessing and almost-disjointness features, and is shown to be sufficient for
carrying out de Caux type constructions of topological spaces.
  Our main result states that strong instances of $\clubsuit_{AD}$ follow from
the existence of a Souslin tree. It is also shown that the weakest instance of
$\clubsuit_{AD}$ does not follow from the existence of an almost Souslin tree.
  As an application, we obtain a simple, de Caux type proof of Rudin's result
that if there is a Souslin tree, then there is an $S$-space which is Dowker.
