LIZ MUNSELL: Today we're inaugurating a sculpture by the Argentinian-born, London-based artist, Amalia Pica. It's called "Now, Speak!" It's a cast concrete lectern, that's a platform for the public's voice and for invited speakers today. Most of them are addressing civil rights issues through their speeches which they've chosen from history. The only requirement of the piece is that the speaker must choose a speech by somebody who has different physical characteristics from them. That way there's an element of displacement and interpretation of history over time.