Houses are amazingly complex repositories. What I found, to my great surprise, is that whatever happens in the world - whatever is discovered or created or bitterly fought over - eventually ends up, in one way or another, in your house. Wars, famines, the Industrial Revolution, the Enlightenment - they are all there in your sofas and chests of drawers, tucked into the folds of your curtains, in the downy softness of your pillows, in the paint on your walls and the water in your pipes.