A coolgardie safe is basically a box with open sides, back & front with a door. The front back & sides are covered in hessian made from old feed sacks. On top of this box is a tray of water. The hessian overlaps into this water tray & the water soaks down through the hessian sides & keeps the inside cool.
A spring house is a building built over or below a spring so that the water flows though this building & keeps the inside cool.
