Dear David, Could it be that there is water under the section when it is
placed on the hot-plate or heated in an oven. We drain our slides
vertically for a minute or so, then blot dry between several layers of
slighty damp filter paper, then place flat on a 60C hot-plate for 5
minutes before staining. One of my old bosses in Adelaide has a good web
site you could check out,
http://home.primus.com.au/royellis/ ,

David.

David Taylor
Laboratory Manager
Drs King & Mower
Adelaide, Australia

PS. Sorry Roy thats old boss not old boss!