No alcoholic beverage is surrounded by more stringent ceremony or has carried such historic political significance as port. As is well known, it is always passed to the left (except for filling the glass of one’s neighbour to the right before beginning the circuit). In the eighteenth century, it marked you out as a Whig (Tories drank claret). No other wine has lent its name to a birthmark – port-wine stain – or, confusingly, been considered both the cause and the cure of a medical condition – gout. Pitt the Younger, who was prescribed a bottle a day for his gout, becoming in due course “a three-bottle man”, died aged 46.Port was eighteenth-century Britain’s favourite tipple (unless you were a Jacobite or a Tory, that is), made exclusively from gra