It must have happened on Christmas Eve in some great town in a time of terrible frost. I have a vision of a boy, a little boy, six years old or even younger. This boy woke up that morning in a cold damp cellar. He was dressed in a sort of little dressing-gown and was shivering with cold. There was a cloud of white steam from his breath, and sitting on a box in the corner, he blew the steam out of his mouth and amused himself in his dullness watching it float away...