Back when the Brits used to snatch men off the streets to make them sailors, one young impressee was complaining about how he had never gone so long without getting his rocks off. The bosun laughed and said once he was off duty he should go below decks, find a certain barrel in a certain place, and shove his tonker through the knothole. The next day when the sailor saw the bosun again he said he had done what he was told and had gotten the best blowjob of his life. The bosun replied that he was glad the sailor enjoyed it because that night it was going to be the impressee's turn in the barrel.