 Moulins are parts of the internal structure of glaciers, that carry meltwater from the surface down to wherever it may go.Water from a moulin often exits the glacier at base level, sometimes into the sea, and occasionally the lower end of a moulin may be exposed in the face of a glacier or at the edge of a stagnant block of ice.Water from moulins may help lubricate the base of the glacier, affecting glacial motion.