At lunchtime on Ascension Day the connecting door between Brasenose and Lincoln Colleges is opened and members of Brasenose are entitled to be entertained to free beer by Lincoln. There are various stories given as reasons for this custom, the two most popular being (1) that a Brasenose man was pursued by a town mob and was murdered at the gates of Lincoln because the Lincoln students refused to aid him by opening them, and (2) that a Lincoln man killed a Brasenose man in a duel. It became the custom for Lincoln to taint the beer with ground ivy to discourage the Brasenose students from taking too great an advantage of the hospitality.