The dockyard apprentices had a revenge tactic for people who gave then too much stick. The yard being ancient in places, to the point of still having hooks i the wall where they used to hang people, also used to have some strange toilet arrangment, whereby there wasn't a flush, but a constantly running flow of water under the seats. So, the trick was to wait until victim was trousers down, then set fire to a wad of newspaper and chuck down the end trap so that the flow of water would take flaming paper under the rest of the traps, and gently singe backsides.
Whatever happened to 'engineers blue'?