Geograph - photograph every grid square

Houses in Wilmore St - During a fairly recent visit by an American friend of a friend I pointed out the plaque on the wall of the almshouses in the foreground which stated the occupancy since 1485 (presumably not by the same families). When they saw the inscription they exclaimed "gee! that's before Columbus came to America!" They were then, like me, puzzled by the name of the building next to it, the one with the half-timbered first floor. It is called Bastard Hall. Can anyone tell my why the name?