Everyday Londoners flock here to walk their dogs, to run, to ride, to row, to swim (even if they have to break the ice on Christmas morning!). In the centre of Hyde Park is the Hudson Bird Sanctuary memorial erected in honour of the naturalist Hudson. Before this is a sculpture by Jacob Epstein (1925) depicting Rima, the spirit of nature. On Saturdays, Sundays and Bank holidays, weather permitting, the orators come to put up their soapboxes or their step ladders in the open-air at the north east corner of Hyde Park (Speaker's Corner) not far from Marble Arch, in the place where there used to be a tree known as the Reformers Tree. According to a centuries old tradition the speakers can talk about any subject which is not contrary to good manners.