Desalinating sea water or salt water to make clean drinking water
Large glass bowl, glass jam jar, cling film / glad wrap, stone
Put the jar in the bowl. Fill around the jar with salt/sea water - make sure that the jar does not lift up - you don't want any salt water in it. Cover the top with cling film. Place a rock in the centre so that it is above the jar. Place in the sun.
The evaporating water collects and condenses on the cling film and the rock weights it down so that it collects and falls into the jar. Quick to set up - take a few hours to collect some water.
For an alternative version you can dig a hole and cover it to recover water from damp earth or leaves you add - see attached instruction sheet.