Give Biomeda's Crystalmount or Shandon's Aquaperm a try. They work pretty
well. Just apply over the sections and let it dry without coverslip. After
it has dried, you can coverslip the sections with an organic solvent based
resin for permanent storage. In my hands, these are the only aqueous
mounting media that come close to organic resins in terms of refractive
index and thus section transparency. I must however say that they are too
pricey in my opinion.
As to the use of automated coverslippers with these media, I have no
experience.

Paul
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Paul Klosen, PhD
CNRS UMR 7518 Neurobiologie des Fonctions Rythmiques et Saisonnieres
Universite Louis Pasteur  12, rue de l'Universite
F-67000 Strasbourg, FRANCE
Tel. 03.88.35.85.04  Fax. 03.88.24.04.61
========================klosen@neurochem.u-strasbg.fr=========================