A warm may night in Paris, 1903.     A hundred thousand Parisians left their homes in the middle of the night, streaming in crowds toward Saint-Lazare and Montparnasse, the railway stations.    Some hadn’t even gone to sleep, others had set the alarm for an absurd hour, then slipped out of bed, washed noiselessly, and bumped into things searching for their jackets. In some cases whole families set out, but for the most part they were single individuals, often against all logic or good sense. The wives in their beds stretched out their legs into the now-empty part. Parents exchanged a few words, deduced from the discussions of the day before, of the days before, of the weeks before. Words focused on the independence of their children. The father rose from his pillow and looked at the time. Two o’clock.    t was a strange noise because a hundred thousand people at two in the morning are like a stream that flows in an empty bed, the rocks vanished, the pebbles silent. Only water on water.…