Makeshift Urinals
During the Korean War, Vietnam War, Operation Desert Storm etc., "piss tubes" were used as makeshift urinals. To make one, soldiers would affix an inverted water bottle on one end of a rigid tube, burying the other end. Removing the base of the bottle made a funnel which would be left at the proper height. Deposited urine simply soaked into the ground. When the area became saturated, the device was relocated.
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