Cover slips for slides.

      Does anyone know what to use to keep a cover slip on a slide? I was using rubbing alcohol but it evaporates too rapidly. I am curious though if pure pharmacy grade glicerin,( pardon the spelling) will work. I am making some slides for the November meeting and hope to have at least a half dozen made up buy then.

     I am hoping to see Barry at the October meeting so I can ask him.