I just remembered something interesting. When I was living in Florida we went to visit The Barnacle which was Commodore Ralph Munroe's house (you boating types will love his story). The Commodore was one of the first white inhabitants of what is now the Miami area. His house is naturally air conditioned!

The house is two stories and octagonal in shape. There is a central shaft around which the rooms are arranged. The house sits on a cistern full of water. The cistern has a concrete cap. The warm air in the house rises through and exhausts from the central shaft drawing cool moist replacement air in through that cistern and into the house. In order to keep things from mildewing in the house all of the closets and drawers are built into the wall and have the same flow of air moving through them. That way there is no damp still air to promote the growth of fungus.

The day we visited the house it was over 95 degrees F outside. Inside the temperature was 75 degrees and very comfortable. It works and should be the model for homes in the southern climes!