We just use melted paraffin in a vacuum oven. The paraffin is kept at 60C
in small glass petri dishes and is moved from dish to dish every half hour
for about 3 hours. Then you fill a plastic mold halfway, let the paraffin
cool until it's hard enough to pour more on without it melting again, but
not fully cooled, put in your tissue, cover it with melted paraffin and let
it cool overnight.
You don't need the vacuum oven, it just gets rid of bubbles in the
You also need to use heated instruments (we just warm them briefly in an
alcohol lamp flame) when transferring the embryo in paraffin.
An overcivilized people grow complacent and careless and leave the door open
for a tribe of fanatical savages, through a mixture of luck, treachery, and
the foulest inhumanity, to usurp their place for a few years.
-Richard Adams, "Shardik", 1974
Histonet mailing list