Love those monitor tops
Great Collection Graham, that second picture, with the square top. I believe that was a 1950s refrigeration unit that replaced the old bee-hive top. So the base is old and the top "new" I have only ever seen one of those.
I have one myself and updated the insides with a new frig - the old one was broken. Lotsa fun venting that old sulfer-dioxide and cleaning it out.