During Second World War air raids, some explosives were dropped with parachutes attached. This slowed the descent of the mine sufficiently to prevent it burying itself too deeply in the ground, as a mine that is too deeply buried will not be as effective. In some areas 'chandelier flares' were used to enable aircraft to see their targets - these descended slowly on parachutes, exploding while still in the air and throwing a bright light over the landscape beneath.