A "Barrel" of Water
undated U.S. Army Signal Corps photo

A demonstration photo of desert survival techniques shows four canteens being filled from the water of one barrel cactus on maneuvers in the Mojave desert near Indio, California. The pleated shape of the barrel cactus allows it to expand when it rains and store water in its spongy tissue, though the water becomes extremely alkaline-tasting and slimy. It shrinks in size during dry times as it uses the stored water.

from the Webmaster's collection