When dawn came this morning, the atmosphere over San Francisco was crystal clear. The first rays of sun colored the city with glitter and sparkle so that it stood on its hill tops with a kind of oriental splendour. But then at 9 o'clock, thunder hit and swept in from the ocean, and at 10, drops of rain the size of quarters splattered on the streets and there was a such a downpour that San Francisco seldom sees - certainly not in May! This was the day that Nicholas and Claudia had had someone in for lunch.