Walking through a deserted city in the hours before dawn is sobering way beyond the undoing of the effects of alcohol. Every thing is familiar, and everything is strange. It's as if you are the only survivor of some mysterious calamity which has emptied the place of its population, and yet you know that behind the shuttered and curtained windows people lie sleeping in their tens of thousands, and all their joys and disasters lie sleeping too. It makes you think of your own life, usually suspended at that hour, and how you are passing through it as if in a dream. Reality seems very unreal.