Wrapping your leftover expedition carbide in bread and feeding it to seagulls passed the journey back to Blighty on the Santander/Plymouth ferry.We used to put a lump of carbide in a plastic pop bottle with a dab of water then screw the top on tight. Everyone sat around in a wide circle and the bottle lobbed in the middle. The 'game' was to kick the ever expanding bottle away every time it came near. Eventually it exploded, usually under somebody's chair. Beer was involved and the game usually took place late at night