See also botijos: https://en.wikipedia.org/wiki/Botijo https://en.wikipedia.org/wiki/Botijo (Single-walled porous clay pots for storing water in. Water flows

See also botijos: https://en.wikipedia.org/wiki/Botijo https://en.wikipedia.org/wiki/Botijo (Single-walled porous clay pots for storing water in. Water flows through the clay, very slowly, evaporates from the outside, and keeps the water inside cool. I imagine they break forever if you put a liquid that's not water in them as the pores clog up.) I know someone with one. It works really well, and is ideal for camping or off-grid trips.