Aniseed ball

In the spring of 1939, a magnetically attached limpet mine was constructed in Britain for underwater sabotage actions in the upcoming war. The mines exploded when a cocked spring hit a detonator. Between the striker and the detonator an aniseed ball was placed, as each had precisely the same spherical shape and consistently dissolved in water after 35 minutes, leaving the saboteur time to escape. The first of these mines was sent to Yugoslavia and Egypt in the autumn of 1939. ==References==